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Significant breakthroughs have been made in the development of surface-enhanced Raman scattering (SERS) substrates constructed by depositing plasmonic Ag onto nanostructured platforms. AlOOH is widely fabricated using hydrothermal, microwave, and microemulsion methods. Among these, the high catalytic activity of AlOOH prepared by the microemulsion method is derived from its high specific surface area, more active surface OH groups, and multi-active adsorption sites. And nanomaterials with such excellent properties have not yet been fabricated on a SERS-based platform to improve the Raman-enhanced properties of Ag achieving high-sensitivity detection of probe molecules especially with affinity for OH groups. The precious metal Ag has long been known to serve as traps to capture electrons and holes generated by plasmon resonance, reducing electron-hole recombination and exhibiting high activity in photocatalytic processes. In this work, to demonstrate the SERS substrate activity of the AlOOH@Ag complex, it has been successfully applied to identify congo red (CR) molecules with high sensitivity, methyl blue (MB) and methyl orange (MO), enabling trace-level detection with enhanced performance much stronger than Ag substrate.

Plant cells continuously experience mechanical stress resulting from the cell wall that bears internal turgor pressure. Cortical microtubules align with the predicted maximal tensile stress direction to guide cellulose biosynthesis and therefore results in cell wall reinforcement. We have previously identified Increased Petal Growth Anisotropy (IPGA1) as a putative microtubule-associated protein in Arabidopsis, but the function of IPGA1 remains unclear. Here, using the Arabidopsis cotyledon pavement cell as a model, we demonstrated that IPGA1 forms protein granules and interacts with ANGUSTIFOLIA (AN) to cooperatively regulate microtubule organisation in response to stress. Application of mechanical perturbations, such as cell ablation, led to microtubule reorganisation into aligned arrays in wild-type cells. This microtubule response to stress was enhanced in the IPGA1 loss-of-function mutant. Mechanical perturbations promoted the formation of IPGA1 granules on microtubules. We further showed that IPGA1 physically interacted with AN both in vitro and on microtubules. The ipga1 mutant alleles exhibited reduced interdigitated growth of pavement cells, with smooth shape. IPGA1 and AN had a genetic interaction in regulating pavement cell shape. Furthermore, IPGA1 genetically and physically interacted with the microtubule-severing enzyme KATANIN. We propose that the IPGA1-AN module regulates microtubule organisation and pavement cell shape.

Spontaneous multi-scale supramolecular assembly (MSSA) and multi-scale selectivity (MSS) are realized in ionic liquid-based extraction systems, which can pave the way for the development of supramolecular chemistry and separation chemistry.

Reactive oxygen species (ROS) production by activation of microglia is considered to be a major cause of neuronal dysfunction, which can lead to damage and death through direct oxidative damage to neuronal macromolecules or derangement of neuronal redox signaling circuits. BAP31, an integral ER membrane protein, has been defined as a regulatory molecule in the CNS. Our latest studies have found that BAP31 deficiency leads to activation of microglia. In this study, we discovered that BAP31 deficiency upregulated LPS-induced superoxide anion production in BV2 cells and mice by upregulating the expression level of p22phox and by inhibiting the activation of Nrf2-HO-1 signaling. Knockdown of p22phox/keap1 or use of an NADPH oxidase inhibitor (apocynin) reversed the production of superoxide anion and inflammatory cytokines, which then reduced neuronal damage and death in vitro and in vivo. These results suggest that BAP31 deficiency contributes to microglia-related superoxide anion production and neuroinflammation through p22phox and keap1. Furthermore, the excess superoxide anion cooperated with inflammatory cytokines to induce the damage and death of neurons. Thus, we determined that BAP31 is an important regulator in superoxide anion production and neuroinflammation, and the downstream regulators or agonists of BAP31 could therefore be considered as potential therapeutic targets in microglial-related superoxide anion production and neuroinflammation.

Plasmon-assisted reactions have different reaction mechanisms than conventional chemical reactions occurring in solutions, and the hot electrons produced by plasmon decay play an irreplaceable role...

Comparatively revealing the complexation behavior of trivalent actinides and lanthanides with functional ligands in aqueous solution is of great importance to enrich our knowledge on the fundamental coordination chemistry of trivalent f-block elements and to control the fate of minor actinides in nuclear fuel cycles. In this work, the complexation of Am(III) and Nd(III), representatives for trivalent actinides and lanthanides, respectively, with a N,O-hybrid ligand 6-(dimethylcarbamoyl)picolinic acid (DMAPA, denoted as HL) was investigated by absorption spectroscopy, calorimetry, X-ray crystallography, and density functional theory (DFT) calculations. Successive formation of 1:1, 1:2, and 1:3 (metal/ligand) complexes of Am(III) and Nd(III) with DMAPA was identified, and the corresponding thermodynamic parameters were determined. The binding strength of Am(III) with DMAPA is slightly stronger than that of Nd(III), and the complexation of Nd(III) with DMAPA is mainly entropy-driven. The crystal structure of the 1:2 Nd(III)/DMAPA complex and the DFT calculation shed additional light on the coordination and structural characteristics of the complexes. In contrast to the Nd-N bond in the Nd(III)/DMAPA complex, the Am-N bond in the Am(III)/DMAPA complex exhibits more covalency, which contributes to the slightly stronger complexation of Am(III) with DMAPA.

4,4’-Dithiobisbenzoic acid (DTBA) is equivalent to two 4-mercaptobenzoic acid (pMBA) molecules connected together after losing H+, and this bimolecular mechanism of DTBA efficiently promotes the ionization reaction. Under the irradiation of laser light, DTBA molecules are broken to form bimolecules similar to pMBA, and this kind of bimolecular coupling greatly increases the probability of binding with Ag NPs. Also, this molecule has the carboxylic acid group, which leads to a certain sensitivity to pH. In this article, through the comparison of DTBA and pMBA parallel experiments, it is clear that DTBA has better Raman activity, higher reaction efficiency, and more stable reaction than pMBA. The occurrence of this highly efficient ionization reaction under the monitoring of surface-enhanced Raman spectroscopy (SERS) provides a certain value for the progress of further related reactions, and it also has a wide range of applications in pH sensors and intracellular pH monitoring.

Six new (1-6) and two known (7, 8) alkaloids that were chemically inseparable geometrical isomers (two isomers present in a 1:1 ratio for 1-4 and 6 and a 1:3 ratio for 5, 7, and 8) were identified from Stephania cepharantha. Their structures and absolute configurations were determined by spectroscopic data analyses and comparison of their experimental and calculated ECD spectra. Moreover, using NOE correlations and DFT-based calculations, the NMR data of each geometrical isomer of 1-6 were assigned. The biological evaluation of 1-8 showed that 5 and 6 have stronger inhibitory effects (IC50 values, 12.0 and 12.6 μM, respectively) than minocycline (IC50 value, 17.5 μM) against NO production in overactivated BV2 cells, suggesting they have great potential in the development of neuroinflammatory therapeutics for treating neurodegenerative diseases.

Crystals of U(VI) (UO22+) complexes with N,N,N′,N′-tetramethyl-2,2′-bipyridine-6,6′-dicarboxamide (TMBiPDA) and N,N,N′,N′-tetramethyl-1,10-phenanthroline-2,9-dicarboxamide (TMPhenDA) were isolated from different solutions under variable reaction conditions, and the structures were determined by single-crystal X-ray diffraction. All are dimeric complexes bridged by ligand atomic O and molecular O2, denoted as U–O–U′ and U–O2–U′ tectons, respectively. The U–O–U′ dimer is composed of two pentagonal bipyramids of the UO22+ moiety sharing a bridging O-apex, while the U–O2–U′ tecton is composed of two hexagonal bipyramids sharing a peroxo-edge. The two uranyl groups in both U–O–U′ and U–O2–U′ tectons supported by TMBiPDA share one equatorial plane. However, bent U–O2–U′ tectons supported by TMPhenDA have been observed in crystals isolated from different solvents. Dimeric complexes pack into crystal materials by abundant C–H⋯O interactions, between the C–H donors from amide methyls and aromatic rings of ligands and the O-acceptors from the perchlorates, uranyl groups, and peroxide bridge. Another non covalent interaction driving the supramolecular assembly is the π–π interactions between the parallel aromatic rings. Multiple techniques, including absorption spectrophotometry, Raman spectroscopy, and electro-spray ionization – mass spectrometry (ESI-MS), were utilized to understand the pathway to the formation of the uranyl dimers in solutions. Results indicate that the U–O–U′ or U–O2–U′ tectons are yielded, through sequential redox reactions of the uranyl group, from the same precursor [UO2L]2+ and the peroxide ligand O22− that formed in situ. The nature of ligands as well as the reaction conditions, such as temperature, solvent, pH, and light, etc., plays significant roles in the selection of the bridging ligands (O2− or O22−) in crystal materials.

Ischemic stroke is a severe neurological disease without known effective therapy. Microglia-mediated neuroinflammation plays an important role in ischemic stroke. Therefore, finding a safe and effective microglial activation inhibitor might lead to an effective therapeutic strategy against ischemic stroke. In this project, our goal was to explore both the mechanism and effect of pterostilbene in MCAO/R rats. The potential effect of pterostilbene on ischemic stroke was tested using MCAO/R rats and its effect on microglial activation was tested in LPS-stimulated BV-2 cells. In vivo, pterostilbene decreased the neurological scores, brain water content and infarct volume in MCAO/R rats. Pterostilbene increased the number of mature neurons, decreased the number of activated microglia, and reduced iNOS and IL-1β mRNA expression. Pterostilbene inhibited phosphorylated-IκBα expression, thus promoting IκBα expression and inhibiting ROS overexpression. In vitro, pterostilbene inhibited the expression of inflammatory cytokines and suppressed NAPDH activity as well as activation of both the NF-κB pathway and ROS production. To our knowledge, our study is the first to demonstrate that pterostilbene-mediated alleviation of cerebral ischemia and reperfusion injury in rats may be correlated with the inhibition of the ROS/NF-κB-mediated inflammatory pathway in microglia, indicating the potential for the use of pterostilbene as a candidate therapeutic compound for ischemic stroke.

A phytochemical investigation of the aqueous EtOH extract of Bletilla striata tubers afforded 34 phenanthrene and 9,10-dihydrophenanthrene derivatives, including four new compounds, 1-4. These compounds were identified using physicochemical analyses and various spectroscopic methods. Twelve of these compounds were resolved into their enantiomers, and the absolute configurations were determined by comparison of experimental and calculated ECD spectra. The antineuroinflammatory activities were evaluated by measuring the inhibition of nitric oxide production in lipopolysaccharide-stimulated BV-2 microglial cells. Compounds 7, 32, and 33 displayed inhibitory activities, with IC50 values of 1.9, 5.0, and 1.0 μM, respectively, suggesting that they should be subjected to development as potential inhibitors of neuroinflammation.

The stability constants (log β) of 1:1 uranyl complexes with three N,O-mixed donor ligands (L = 2,2'-dipyridyl-6,6'-dicarboxylate, 3,3'-dimethyl-2,2'-bipyridine-6,6'-dicarboxylate, and 1,10-phenanthroline-2,9-dicarboxylate, denoted as BiPDA, DmBiPDA, and PhenDA, respectively) in aqueous and DMSO/20%(v)H2O solutions were determined by spectrophotometry in 0.1 M tetraethylammonium perchlorate. The effects of ligand preorganization, steric hindrance, and solvation on the binding strength of U(VI) with the three ligands were discussed. In aqueous solution, PhenDA forms stronger complexes with U(VI) than BiPDA due to its well-preorganized structure. In DMSO/20%(v)H2O solution, in contrast, the strong solvation effect of DMSO on the ligands reduces the energy gap between the trans- and cis-conformations of BiPDA, resulting in log β(UO2(BiPDA)) > log β(UO2(PhenDA)). The steric hindrance of methyl groups on DmBiPDA makes the complex UO2(DmBiPDA) of the lowest stability in both aqueous and DMSO/20%(v)H2O solutions. Single-crystal structural data of U(VI) complexes with the three ligands indicate that the ligand coordinates with UO22+ via aromatic nitrogen atoms and carboxylate oxygen atoms. There is no clear correlation between the trend of the stability constants in solutions and the U-N/O bond lengths of the three crystal complexes. Nevertheless, DmBiPDA coordinates to UO22+ in a high-strain fashion as a result of the steric hindrance of methyl groups while BiPDA in a low-strain fashion, which is in accordance with the relative complexation strength of the two respective complexes. The results from this work help us understand the effect of ligand preorganization and solvation on the binding strength of actinides with multidentate N,O-mixed ligands in solid and solutions, which is of importance in designing ligands for the partitioning of actinides from nuclear wastes.

Based on a SERS study, the plasmon-assisted coupling reaction of p-iodoaniline (PIAN) to p,p′-diiodoazobenzene was investigated. This model plasmon-assisted reaction exhibits an outstanding SERS performance with the limit of detection as low as 10–13 M. Under low concentrations, the control of the cis–trans isomerization of p,p′-diiodoazobenzene was achieved by characterizing the Raman peak intensity at 1432 cm–1 of the coupling reaction catalytic product. We present the regulation strategy for the isomerization of azobenzene derivatives enabled here, through the controlled adjustment of reactant concentration, and expand the application of SERS technique.

A novel and efficient uranium capture strategy based on self-assembly is developed in an ionic liquid extraction system, by which the one-step separation and solidification of uranium are realized. This not only provides a promising method for separating metal ions but also promotes the development of a supramolecular assembly both in mechanism and application.

The present study aimed to investigate the association between the serum SIRT1 protein and the severity of spinal cord injury (SCI) as well as the neurological recovery in mice. In this study, the wild-type (WT), Mx1-Cre+ SIRT1loxP/loxP (Mx1), and LCK-Cre+SIRT1loxP/loxP (LCK) mice were subjected to sham surgery, mild, moderate, or severe SCI, respectively. The serum was collected at intervals of 12 h, 1 day (d), 3 d, 5 d, 7 d, 10 d, 14 d, and 21 d after the injury. The locomotor function of all the animals was assessed using the Basso mouse scale (BMS) and the serum SIRT1 proteins were analyzed using enzyme-linked immunosorbent assay (ELISA). The results demonstrated that about 7–10 d after SCI, the levels of SIRT1 protein in the serum correlated significantly with the severity of the injury and at 28 d post-injury, there was a distant neurological recovery (BMS score). The serum SIRT1 concentration in both the Mx1 and LCK mice in the sham group was significantly reduced compared to that in the WT mice, and there was a delayed increase in the serum SIRT1 levels after injury. These findings indicate that the SIRT1 concentrations in the serum of the SCI mice closely correlated with the acute severity and neurological outcome.

Hypertension causes a substantial burden to society. Some studies found that hypertension was associated with the working type and working hours. The purpose of the current study is to assess the dose–response relationship between working hours and hypertension. Data of 12,080 adults aged 18 to 65 years who attended the China Health and Nutrition Survey (CHNS) between 1989 and 2011 were analyzed. Hypertension was determined based on systolic and/or diastolic blood pressure measures, or having doctor-diagnosed hypertension. Multivariable Cox regression and restricted cubic spline to assess the dose–response relationship between working hours and hypertension. A total of 12,080 participants including 5852 females and 6228 males. By the last follow-up (2011), a total of 830 participants were hypertensive, with an incidence of 6.9%. After adjusting socio-demographic, lifestyle factors, as well as occupation type, compared with those who worked 35 to 49 hours per week, participants who worked no more than 34 hours per week (HR: 1.21, 95%CI: 1.03–1.41) and at least 56 hours per week (HR: 1.38, 95%CI: 1.19–1.59) had a higher risk of hypertension. The significant association between long working hours (at least 56 hours per week) and hypertension was observed among females (HR: 1.38, 95%CI: 1.16–1.64) and males (HR: 1.36, 95%CI: 1.04–1.78). Among manual workers, the relationship between long working hours and hypertension was observed (HR: 1.49, 95%CI: 1.10–2.02). The relationship between long working hours (HR: 1.21, 95%CI: 1.01–1.44) and short working hours (HR: 1.37, 95%CI: 1.16–1.61) and hypertension was observed among nonmanual workers. The hazard ratio of hypertension and working time displayed U-shape non-linear relationship (Ptrend

Background Increasing evidence has shown that microglia-induced neuroinflammation is involved in the pathogenesis of ischemic stroke. Stepharine, one of the alkaloids extracted from Stephania japonica (Thunb.) Miers, exhibited strong inhibitory effect on microglial overactivation. However, it is not known whether it has the potential to prevent ischemic stroke. Methods The neuroprotective and anti-neuroinflammatory effects of stepharine were investigated in vivo and in vitro, using a rat model of middle cerebral artery occlusion (MCAO) and lipopolysaccharide (LPS)-stimulated BV-2 cells, respectively. Results In vivo, stepharine (500 μg/kg) suppressed neurological deficits scores, brain water content and cerebral infarct volume induced by MCAO. Moreover, stepharine (500 μg/kg) inhibited NeuN+ cells loss and Iba-1+ cells increase in the MCAO ischemic cortex. In vitro, stepharine (10, 30 μM) substantially inhibited nitric oxide release as well as the mRNA and protein expression of pro-inflammatory mediators [inducible nitric oxide synthase, interleukin (IL)-6, tumor necrosis factor (TNF)-α, IL-1β] in LPS-activated BV-2 cells. LPS-induced increase of TLR4 expression, IκBα phosphorylation, and NF-κB p65 nuclear translocation was inhibited by stepharine (10, 30 μM). Molecular docking analysis showed that stepharine directly interacted with TLR4. SPR assay further confirmed that stepharine could bind to the TLR4/MD2 complex. Meanwhile, stepharine exhibited neuroprotective effects on SH-SY5Y cells cultured with LPS-treated conditioned medium. Conclusion Our study demonstrated for the first time that stepharine improved the outcomes in MCAO rats, reduced neuronal loss, and suppressed microglial overactivation via the inhibition of TLR4/NF-κB pathway. These results suggest that stepharine might be a potential therapeutic agent for the treatment of ischemic stroke.

Neuroinflammation is linked to neurodegenerative diseases, manifested by the microglial-released over-production of nitric oxide (NO). However, so far there is no effective strategy regarding curing or preventing neurodegenerative diseases. Triterpene saponins from Xanthoceras sorbifolium were proved to be capable of eliciting a protective effect in neurodegenerative diseases. Thus, a systematic chemical study on the 70% ethanol extract of X. sorbifolium was conducted, leading to the identification of 22 compounds, including four previously undescribed triterpenes saponins and 14 known ones, along with four alkaloids. Their structures were elucidated by physicochemical and spectral methods. The in vivo anti-AD effects of 1-18 were predicted with a field-based 3D-QSAR model and anti-neuroinflammatory activities were assayed in BV-2 cells by assessing LPS-induced NO production and examine levels of iNOS, TNF-α, IL-1β, and IL-6 to support the predicted results. As a result, compounds 14, 16, 19, and 20 could have therapeutic potentials for neurodegenerative diseases due to their potent anti-neuroinflammatory activities.

Nine undescribed (1–4, 6–10) sesquiterpene coumarins, together with a new natural one (5) and ten known ones (11–20), were isolated from the low polarity fraction of the 95% ethanol extract of the resin of Ferula sinkiangensis. Their structures were elucidated based on the comprehensive analysis of HRESIMS, 1D and 2D NMR data. The absolute configurations were determined by comparison of experimental and calculated ECD spectra. All the identified SCs were evaluated for their anti-neuroinflammatory activities in LPS-induced BV-2 cells. Ferusingensine G (8) displayed a significant inhibitory effect on nitric oxide (NO) production with an IC50 value of 1.2 μM. The results suggested that natural SCs might be served as potential neuroinflammatory inhibitors.

Uranyl, a strong Lewis acid, forms stable complexes with relatively hard donors and it is commonly believed that uranyl complex with trialkylamine is stabler than trialkylphosphine. However, there are no thermodynamic parameters to evaluate the complexation stabilities of R 3 N-UO 2 2+ and R 3 P-UO 2 2+ . Nitrilotri-3-propanoic Acid (NTPA) and Tris(2-carboxyethyl) phosphine (TCEP) possess similar skeleton. The set of isostructural ligands is a perfect pair to assess the differences of uranyl (UO 2 2+ ) complexes with trialkylamine versus trialkylphosphine. The protonation reactions of NTPA and TCEP were studied by potentiometry and calorimetry, and the uranyl complexation with both the ligands were studied by potentiometry. The results indicate that central trialkylamine in NTPA has a higher affinity for the proton than trialkylphosphine in TCEP. The complexation of uranyl with NTPA is stabler than TCEP with 1.2 logarithmic units. Striking differences imply the central nitrogen of NTPA and phosphorus of TCEP definitely participate in uranyl complexation. The higher stability of UO 2 2+ /NTPA versus UO 2 2+ /TCEP is intuitively attributed to stronger bonding of N-UO 2 2+ than P-UO 2 2+ because the only differences between TCEP and NTPA are the central atoms.

Interaction between uranium(VI) and aminopolycarboxylic acids could significantly influence the chemical behavior of uranium(VI) in the processing and disposal of nuclear wastes. Trans-1,2-cyclohexanediaminetetraacetic acid (CDTA) is a commonly used aminopolycarboxylic acid, but its complexation with uranium(VI) has not been sufficiently studied. In this study, stability constants of CDTA protonation and U(VI)-CDTA complexes at different temperatures were measured by potentiometry. Their enthalpies and entropies were obtained from van’t Hoff plots. As a result, four U(VI)-CDTA species, UO2(H2CDTA), UO2(HCDTA)-, UO2CDTA2- and UO2(OH)CDTA3-, were identified at pH 3-6 and their coordination modes in solution were demonstrated by thermodynamic studies. The proposed coordination modes of UO2(H2CDTA) and UO2(HCDTA)- in solution differ from the reported crystals; the former is bidentate bonding with one carboxylate and the latter is tridentate bonding with iminodicarboxylate.

Nitrilotri–3–propanoic Acid (NTPA) and Tris(2–carboxyethyl) phosphine (TCEP) possess similar skeleton. This pair of isostructural ligands is a perfect set to assess the differences of uranyl (UO22+) complexes with N–tricarboxylate versus P–tricarboxylate. The protonation reactions of NTPA and TCEP were investigated by potentiometry and calorimetry. Complexation of uranyl with the both ligands was studied by potentiometry and structural analysis. The results indicate that central trialkylamine in NTPA has a higher affinity for the proton than trialkylphosphine in TCEP. Crystal structures and NMR analyses indicate that central amine of NTPA and central phosphine of TCEP are not involved in the bonding. NTPA/UO22+ complex is more stable than TCEP/UO22+ complex. This difference cannot be explained by electronic effect of central N and P atoms because of nonbonding interactions. The higher stability of UO22+/NTPA versus UO22+/TCEP may be due to the fact that the central N atom of NTPA has a lower steric hindrance than the central P atom of TCEP. Another possible reason is that UO22+/TCEP complexes have different coordination modes from UO22+/NTPA complexes.

Background Tamarix species are well known as the main host plants of Herba Cistanches, a valuable Traditional Chinese Medicine. They are also traditional medicinal plants themselves and are used to treat spleen problems, leucoderma and ocular conditions. Purpose The aim of the present study was to investigate the anti-inflammatory effect of Tamarix hohenackeri Bunge. Methods In the present study, BV-2 microglial cells were used and stimulated with lipopolysaccharide (LPS). Cell viability was tested using the MTT assay. The release of nitric oxide (NO) was determined using the Griess assay. The mRNA level of inducible nitric oxide synthase (iNOS), tumor necrosis factor α (TNF-α), interleukin (IL)-1β and IL-6 were investigated by quantitative real-time PCR (qRT–PCR). The protein levels of phosphorylated of IκBα, ERK and MEK, as well as the cytoplasmic and nuclear NF-κB p65 were tested by Western blot analysis. The translocation of the NF-κB p65 subunit from the cytosol to the nucleus was investigated by immunofluorescence staining. Results Ethyl acetate (EtOAc) extract of Tamarix hohenackeri Bunge significantly inhibited the release of NO. Phytochemical research was performed to produce 13 main constituents. Among them, compounds 6, 7, 10 and 13 were identified to be the effective components with anti-inflammatory activity. These compounds significantly inhibited the production of NO by LPS-activated BV-2 microglial cells. qRT–PCR showed that compounds 6 and 7 significantly suppressed the LPS-induced transcription of genes encoding pro-inflammatory mediators, including iNOS, TNF-α, IL-1β and IL-6. Western blot analysis showed that compound 7 inhibited the LPS-induced phosphorylation of IκBα and antagonized the LPS-induced reduction of cytoplasmic NF-κB p65 and the increase of nuclear NF-κB p65. Immunofluorescence staining showed that nuclear translocation of NF-κB p65 was suppressed by compound 7. Western blot analysis showed that compound 7 inhibited the LPS-induced phosphorylation of ERK and MEK. Conclusion The present study revealed, for the first time, the effective anti-inflammatory agents from T. Hohenackeri. Compound 7 exerted potent anti-inflammatory effects and its underlying mechanism may be associated with its capacity to inhibit NF-κB signaling pathway and the MEK/ERK activation in activated microglia. The compound may be potential candidate therapeutic agent for neurodegenerative diseases.

There is much evidence that surface plasmon photocatalytic reactions can occur on organic molecules on metal surfaces. In this paper, we focus on the photocatalytic reaction of 4-ethynylaniline (PEAN) on silver nanoparticles (Ag NPs) in a liquid environment by surface-enhanced Raman spectroscopy (SERS). Our experiments used SERS to characterize p,p′-diynylazobenzene produced from PEAN via a selective catalytic coupling reaction on Ag NPs. This discovery not only achieved the expected results but also broadens the known plasmon-driven surface catalytic reaction system. In our work, we also regulated the photocatalytic coupling reaction conditions of PEAN on Ag NPs by laser power-dependent and time-dependent SERS spectra.

Four undescribed spiro cyclohexandienonyl naphthalenes (acanthophyllas A–D) and a revised compound were isolated from the roots of Caragana acanthophylla Kom. (Fabaceae). They were identified using extensive spectroscopic data and via chemical methods. Three of them were resolved into their enantiomers, and their absolute configurations were confirmed by comparing the experimental and calculated electronic circular dichroism spectra. Moreover, the anti-inflammatory activities of the compounds were investigated by evaluating their inhibitory effects on nitric oxide production in lipopolysaccharide-stimulated BV-2 cells. Some compounds showed significant inhibitory activities with IC50 values of 8.8–13.4 μM (minocycline, IC50 7.8 μM), indicating that they might serve as potential therapeutic agents for neurodegenerative diseases.

The separation of tridentate actinides from lanthanides and that between Am(III) and Cm(III) is one of the most challenging tasks in the process of partitioning–transmutation of nuclear waste. Herein, we report a novel tridentate N–N–O hybrid ligand, i.e., N-ethyl-N-tolyl-2-amide-1,10-phenanthroline (ETPhenAm), for the selective extraction toward Am(III)/Cm(III) over Eu(III) from HNO3 solutions. ETPhenAm in 3-nitrotrifluorotoluene has excellent Am(III) extraction ability and Am(III)/Eu(III) separation performance. Notably, the good selectivity of ETPhenAm toward Am(III) over Cm(III) suggests that ETPhenAm exhibits good ionic radius selectivity in the interaction with the intraseries cations such as Am(III) and Cm(III). Extractive complexes of formula M(NO3)3L and M(NO3)3L2 (M = Am, Cm, and Eu) are identified in the extraction system. HNO3 concentration in the aqueous phase heavily affects the composition of the extractive species in the organic phase because of the strong basicity of ETPhenAm. Extraction observations are validated by determining the protonation constants of the ligand and the reaction equilibrium constants for the generation of complexes M(NO3)3L and M(NO3)3L2 (M = Nd and Eu) in CH3OH/10%(v)H2O solution. The structures of complexes M(NO3)3L and M(NO3)3L2 are confirmed through X-ray diffraction of compounds [La(NO3)3(ETPhenAm)2] (I), [Nd(NO3)2(ETPhenAm)2]NO3 (II), and [Eu(NO3)2(ETPhenAm)2]NO3∙[Eu(NO3)3(ETPhenAm)(CH3OH)]∙2CH3OH (III).

Complexation of a new macrocyclic compound, 2,6-dimethylformamide-calix[4]pyridine (L1 ), with Eu(III) was studied by spectrophotometry. Stability constants of the Eu(III)/L1 complex in different solvents were determined. The results reveal that L1 forms moderately strong complexes with Eu(III) and other lanthanides in aprotic solvents and shows little binding ability with transition metals. Moreover, the binding strength of L1 weakens significantly in protic solvents. Using 2-bromodecanoic acid as the synergistic reagent, L1 extracts Am(III) and Eu(III) successfully with a separation factor of SFAm/Eu=1.3, and the distribution ratios of Am(III) and Eu(III) increases as the aqueous acidity is decreased. DFT computational studies were conducted to corroborate the solvent extraction data, and compare the coordination properties of Am(III)/Eu(III) complexes with L1 and a related, 2,6-diformamide-calix[4]pyridine (L2 ). The computational results suggest that L2 could form stable complexes [ML]3+ and ML(NO3)3 [where M represent Am(III) or Eu(III)] in aqueous phase, in sharp contrast to the case of L1 where such complexes in aqueous phase are not stable.

Thermodynamics of the U(VI) complexation with picolinic acid (HL) was investigated under constant ionic strength (1.05 mol·kg−1 NaClO4) with multiple techniques, including potentiometry, spectrophotometry and calorimetry. Three stepwise complexes, UO2L+, UO2L2(aq) and UO2L3−, were identified, and their formation constants were determined by potentiometric titrations at 283–313 K. The spectrophotometric work at 298 K further demonstrated the formation of these three complexes. By calorimetric titrations, stepwise enthalpies of the complexation at 298 K were determined to be ΔH11 = −(3.43 ± 0.24) kJ·mol−1, ΔH12 = −(3.3 ± 0.6) kJ·mol−1, and ΔH13 = 9.4 ± 0.6 kJ·mol−1. A formation of the 1:1 and 1:2 complexes is driven by both enthalpy and entropy, but the formation of the 1:3 complex by entropy only. The thermodynamic parameters also suggest that in the 1:1 and 1:2 complexes, picolinate coordinates to U(VI) through the chelation mode, i.e., one carboxylate oxygen and an aromatic nitrogen bind to the U(VI) atom.

The bit-error rate (BER) and outage probability of optical wireless communication (OWC) link for the ground-to-train of the curved track in turbulence with rain is evaluated. Considering the re-modulation effects of raining fluctuation on optical signal modulated by turbulence, we set up the models of average BER and outage probability in the present of pointing errors, based on the double inverse Gaussian (IG) statistical distribution model. The numerical results indicate that, for the same covered track length, the larger curvature radius increases the outage probability and average BER. The performance of the OWC link in turbulence with rain is limited mainly by the rain rate and pointing errors which are induced by the beam wander and train vibration. The effect of the rain rate on the performance of the link is more severe than the atmospheric turbulence, but the fluctuation owing to the atmospheric turbulence affects the laser beam propagation more greatly than the skewness of the rain distribution. Besides, the turbulence-induced beam wander has a more significant impact on the system in heavier rain. We can choose the size of transmitting and receiving apertures and improve the shockproof performance of the tracks to optimize the communication performance of the system.

A model for short-range optical wireless communication (OWC) link under fog-haze random media is presented based on the consideration of beam pointing error. The performance of OWC is analyzed in terms of received power, link margin, signal to noise ratio (SNR) and bit error rate (BER) with different track length, visibility of atmosphere, strength of the atmospheric turbulence, operating wavelength, emitting beam width, and variance of pointing error. It is found that we can ignore the impact of emitting beam width on the link margin, however, there is a optimizing emitting beam width w op for the SNR performance of the channel. The link margin and SNR decrease as the increasing of the track length and the turbulence strength. The link margin and SNR decrease as the meteorological conditions transform from clear, haze to heavy fog. The longer operating wavelength can increase the link margin and SNR. The pointing error caused by beam wander is the dominant factor and it seriously reduces the link margin and SNR, and increases the BER.

Type 2 diabetes mellitus (T2DM) increases the risk of brain atrophy and dementia. We aimed to elucidate deep grey matter (GM) structural abnormalities and their relationships with T2DM cognitive deficits by combining region of interest (ROI)-based volumetry, voxel-based morphometry (VBM) and shape analysis. We recruited 23 T2DM patients and 24 age-matched healthy controls to undergo T1-weighted structural MRI scanning. Images were analysed using the three aforementioned methods to obtain deep GM structural shapes and volumes. Biochemical and cognitive assessments were made and were correlated with the resulting metrics. Shape analysis revealed that T2DM is associated with focal atrophy in the bilateral caudate head and dorso-medial part of the thalamus. ROI-based volumetry only detected thalamic volume reduction in T2DM when compared to the controls. No significant between-group differences were found by VBM. Furthermore, a worse performance of cognitive processing speed correlated with more severe GM atrophy in the bilateral dorso-medial part of the thalamus. Also, the GM volume in the bilateral dorso-medial part of the thalamus changed negatively with HbA1c. Shape analysis is sensitive in identifying T2DM deep GM structural abnormalities and their relationships with cognitive impairments, which may greatly assist in clarifying the neural substrate of T2DM cognitive dysfunction. • Type 2 diabetes mellitus is accompanied with brain atrophy and cognitive dysfunction • Deep grey matter structures are essential for multiple cognitive processes • Shape analysis revealed local atrophy in the dorso-medial thalamus and caudatum in patients • Dorso-medial thalamic atrophy correlated to cognitive processing speed slowing and high HbA1c. • Shape analysis has advantages in unraveling neural substrates of diabetic cognitive deficits

A model of the average capacity of optical wireless communication link with pointing errors for the ground-to-train of the curved track is established based on the non-Kolmogorov. By adopting the gamma-gamma distribution model, we derive the average capacity expression for this channel. The numerical analysis reveals that heavier fog reduces the average capacity of link. The strength of atmospheric turbulence, the variance of pointing errors, and the covered track length need to be reduced for the larger average capacity of link. The normalized beamwidth and the average signal-to-noise ratio (SNR) of the turbulence-free link need to be increased. We can increase the transmit aperture to expand the beamwidth and enhance the signal intensity, thereby decreasing the impact of the beam wander accordingly. As the system adopting the automatic tracking of beam at the receiver positioned on the roof of the train, for eliminating the pointing errors caused by beam wander and train vibration, the equivalent average capacity of the channel will achieve a maximum value. The impact of the non-Kolmogorov spectral index's variation on the average capacity of link can be ignored.