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Abstract Understanding and exploiting the redox properties of uranium is of great importance because uranium has a wide range of possible oxidation states and holds great potential for small molecule activation and catalysis. However, it remains challenging to stabilise both low and high-valent uranium ions in a preserved ligand environment. Herein we report the synthesis and characterisation of a series of uranium(II–VI) complexes supported by a tripodal tris(amido)arene ligand. In addition, one- or two-electron redox transformations could be achieved with these compounds. Moreover, combined experimental and theoretical studies unveiled that the ambiphilic uranium–arene interactions are the key to balance the stabilisation of low and high-valent uranium, with the anchoring arene acting as a δ acceptor or a π donor. Our results reinforce the design strategy to incorporate metal–arene interactions in stabilising multiple oxidation states, and open up new avenues to explore the redox chemistry of uranium.

The genus Schisandra belongs to the family Schisandraceae and grows mainly in south-central and southwestern China. Most of the plants in this genus are used for medicine by their fruits, usually for the treatment of inflammatory diseases. In traditional medicine, Schisandra is also used to stop bleeding, relieve pain, and clear heat. Based on this, many domestic and foreign scholars have conducted systematic studies on its chemical composition, and experimental data show that triterpenoid components are the important material basis for the pharmacological effects of this genus. This paper summarizes the relevant literature on triterpenes of the genus Schisandra from 1983 to 2023. All information and research about this paper was obtained from libraries and digital databases (SciFinder, Medline PubMed, Google Scholar, and CNKI, etc.). At present, there are 335 different kinds of triterpenes isolated from the genus Schisandra, including lanostanes, cycloartanes, nortriterpenoids and pentacyclic triterpenoids, which are mostly found in fruits and vine stems. They have been found to possess various activities such as antitumor, antioxidant, anti-inflammatory, immunomodulatory, neuroprotective, nephroprotective and hepatoprotective.This review systematically summarizes the literature on triterpenoid composition, traditional applications, pharmacology, and exploitation of the genus Schisandra. We hope this paper will provide a valuable reference for further research and development of the resources of this genus.

The accurate and efficient detection of defective insulators is an essential prerequisite for ensuring the safety of the power grid in the new generation of intelligent electrical system inspections. Currently, traditional object detection algorithms for detecting defective insulators in images face issues such as excessive parameter size, low accuracy, and slow detection speed. To address the aforementioned issues, this article proposes an insulator defect detection model based on the lightweight Faster R-CNN (Faster Region-based Convolutional Network) model (Faster R-CNN-tiny). First, the Faster R-CNN model’s backbone network is turned into a lightweight version of it by substituting EfficientNet for ResNet (Residual Network), greatly decreasing the model parameters while increasing its detection accuracy. The second step is to employ a feature pyramid to build feature maps with various resolutions for feature fusion, which enables the detection of objects at various scales. In addition, replacing ordinary convolutions in the network model with more efficient depth-wise separable convolutions increases detection speed while slightly reducing network detection accuracy. Transfer learning is introduced, and a training method involving freezing and unfreezing the model is employed to enhance the network’s ability to detect small target defects. The proposed model is validated using the insulator self-exploding defect dataset. The experimental results show that Faster R-CNN-tiny significantly outperforms the Faster R-CNN (ResNet) model in terms of mean average precision (mAP), frames per second (FPS), and number of parameters.

This paper is intended to review advances in the botanical, traditional uses, phytochemical, pharmacological and development and utilization studies of the genus Chloranthus. Chloranthus, a genus of the family Chloranthaceae, which is mainly distributed in the temperate and tropical regions of Asia, has been used as a folk remedy for swollen boils, snake bites and bruises. Up to now, 418 compounds have been reported from the genus Chloranthus, including 383 terpenoids, 4 coumarins, 6 lignans, 2 simple phenylpropanoids, 4 flavonoids, 6 amides, 5 organic acids and some other types of compounds. Among them, the main chemical constituents are sesquiterpenes and their diterpenoids. Modern pharmacological studies have shown that most of the Chloranthus plants possessed anti-cancer, anti-inflammatory, antibacterial, antiviral, and antimalarial activities. As one of the most important genera in China, Chloranthus should be paid further attention to gathering information about the pharmacological mechanism and value active compounds. This paper summarized the phytochemistry, pharmacology, and uses of genus Chloranthus in order to lay a foundation and provide reference for the follow-up research and wide application of the genus.

Amphioxus (e.g., Branchiostoma belcheri, Bb) has recently emerged as a new model for studying the origin and evolution of vertebrate immunity. Mammalian lymphocyte-specific tyrosine kinase (Lck) plays crucial roles in T cell activation, differentiation and homeostasis, and is reported to phosphorylate both the ITIM and ITSM of PD-1 to induce the recruitment of phosphatases and thus the inhibitory function of PD-1. Here, we identified and cloned the amphioxus homolog of human Lck. By generating and using an antibody against BbLck, we found that BbLck is expressed in the amphioxus gut and gill. Through overexpression of BbLck in Jurkat T cells, we found that upon TCR stimulation, BbLck was subjected to tyrosine phosphorylation and could partially rescue Lck-dependent tyrosine phosphorylation in Lck-knockdown T cells. Mass spectrometric analysis of BbLck immunoprecipitates from immunostimulants-treated amphioxus, revealed a BbLck-associated membrane-bound receptor LRR (BbLcLRR). By overexpressing BbLcLRR in Jurkat T cells, we demonstrated that BbLcLRR was tyrosine phosphorylated upon TCR stimulation, which was inhibited by Lck knockdown and was rescued by overexpression of BbLck. By mutating single tyrosine to phenylalanine (Y-F), we identified three tyrosine residues (Y539, Y655, and Y690) (3Y) of BbLcLRR as the major Lck phosphorylation sites. Reporter gene assays showed that overexpression of BbLcLRR but not the BbLcLRR-3YF mutant inhibited TCR-induced NF-κB activation. In Lck-knockdown T cells, the decline of TCR-induced IL-2 production was reversed by overexpression of BbLck, and this reversion was inhibited by co-expression of BbLcLRR but not the BbLcLRR-3YF mutant. Sequence analysis showed that the three tyrosine-containing sequences were conserved with the tyrosine-based inhibition motifs (ITIMs) or ITIM-like motifs. And TCR stimulation induced the association of BbLcLRR with tyrosine phosphatases SHIP1 and to a lesser extent with SHP1/2. Moreover, overexpression of wild-type BbLcLRR but not its 3YF mutant inhibited TCR-induced tyrosine phosphorylation of multiple signaling proteins probably via recruiting SHIP1. Thus, we identified a novel immunoreceptor BbLcLRR, which is phosphorylated by Lck and then exerts a phosphorylation-dependent inhibitory role in TCR-mediated T-cell activation, implying a mechanism for the maintenance of self-tolerance and homeostasis of amphioxus immune system and the evolutionary conservatism of Lck-regulated inhibitory receptor pathway.

Interleukin-17E (IL-25) is a member of the IL-17 cytokine family that includes IL-17A to IL-17F. IL-17 family cytokines play a key role in host defense responses and inflammatory diseases. Compared with other IL-17 cytokine family members, IL-25 has relatively low sequence similarity to IL-17A and exhibits a distinct function from other IL-17 cytokines. IL-25 binds to its receptor composed of IL-17 receptor A (IL-17RA) and IL-17 receptor B (IL-17RB) for signal transduction. IL-25 has been implicated as a type 2 cytokine and can induce the production of IL-4, IL-5 and IL-13, which in turn inhibits the differentiation of T helper (Th) 17. In addition to its anti-inflammatory properties, IL-25 also exhibits a pro-inflammatory effect in the pathogenesis of Th17-dominated diseases. Here, we review recent advances in the roles of IL-25 in the pathogenesis of inflammation and autoimmune diseases.

Abstract Copper indium sulfide quantum dots (CuInS2 QDs) were incorporated into a nanocrystalline TiO2 film by using spin coating-assisted successive ionic layer adsorption and reaction process to fabricate CuInS2 QD-sensitized TiO2 photoelectrodes for the solid-state quantum dot-sensitized solar cell (QDSSC) applications. The result shows that the photovoltaic performance of solar cell is extremely dependent on the number of cycles, which has an appreciable impact on the coverage ratio of CuInS2 on the surface of TiO2 and the density of surface defect states. In the following high-temperature annealing process, it is found that annealing TiO2/CuInS2 photoelectrode at a suitable temperature would be beneficial for decreasing the charge recombination and accelerating the charge transport. After annealing at 400 °C, a significantly enhanced photovoltaic properties of solid-state CuInS2 QDSSCs are obtained, achieving the power conversion efficiency (PCE) of 3.13%, along with an open-circuit voltage (VOC) of 0.68 V, a short-circuit photocurrent density (JSC) of 11.33 mA cm−2, and a fill factor (FF) of 0.41. The enhancement in the performance of solar cells is mainly ascribed to the suppression of charge recombination and the promotion of the electron transfer after annealing.

Abstract Objectives This study aims to determine a role of interleukin‐17A (IL‐17) in salivary gland (SG) dysfunction and therapeutic effects of targeting IL‐17 in SG for treating autoimmune sialadenitis in primary Sjögren’s syndrome (pSS). Methods Salivary IL‐17 levels and IL‐17‐secreting cells in labial glands of pSS patients were examined. Kinetic changes of IL‐17‐producing cells in SG from mice with experimental Sjögren’s syndrome (ESS) were analysed. To determine a role of IL‐17 in salivary secretion, IL‐17‐deficient mice and constructed chimeric mice with IL‐17 receptor C (IL‐17RC) deficiency in non‐hematopoietic and hematopoietic cells were examined for saliva flow rates during ESS development. Both human and murine primary SG epithelial cells were treated with IL‐17 for measuring cholinergic activation‐induced calcium movement. Moreover, SG functions were assessed in ESS mice with salivary retrograde cannulation of IL‐17 neutralisation antibodies. Results Increased salivary IL‐17 levels were negatively correlated with saliva flow rates in pSS patients. Both IL‐17‐deficient mice and chimeric mice with non‐hematopoietic cell‐restricted IL‐17RC deficiency exhibited no obvious salivary reduction while chimeric mice with hematopoietic cell‐restricted IL‐17RC deficiency showed significantly decreased saliva secretion during ESS development. In SG epithelial cells, IL‐17 inhibited acetylcholine‐induced calcium movement and downregulated the expression of transient receptor potential canonical 1 via promoting Nfkbiz mRNA stabilisation. Moreover, local IL‐17 neutralisation in SG markedly attenuated hyposalivation and ameliorated tissue inflammation in ESS mice. Conclusion These findings identify a novel function of IL‐17 in driving salivary dysfunction during pSS development and may provide a new therapeutic strategy for targeting SG dysfunction in pSS patients.

Abstract The well-defined mammalian slp76-signalosome is crucial for T-cell immune response, yet whether slp76-signalosome exists in invertebrates and how it evolved remain unknown. Here we investigated slp76-signalosome from an evolutionary perspective in amphioxus Branchiostoma belcheri (bb). We proved slp76-signalosome components bbslp76, bbGADS and bbItk are present in amphioxus and bbslp76 interacts with bbGADS and bbItk, but differences exist between the interaction manners within slp76-signalosome components of amphioxus and human (h). Specifically, bbslp76 has a unique WW-domain that blocked its association with hItk and decreased TCR-induced tyrosine-phosphorylation and NFAT-activation. Deletion of WW-domain shifted the constitutive association between bbslp76 and hPLCγ1 to a TCR-enhanced association. Among slp76-signalosome, the interaction between slp76 and PLCγ1 is the most conserved and the binding between Itk and slp76 evolved from constitutive to stimulation-regulated. Sequence alignment and 3D structural analysis of slp76-signalosome molecules from keystone species indicated slp76 evolved into a more unfolded and flexible adaptor due to lack of WW-domain and several low-complexity-regions (LCRs) while GADS turned into a larger protein by a LCR gain, thus preparing more space for nucleating the coevolving slp76-signalosome. Altogether, through deletion of WW-domain and manipulation of LCRs, slp76-signalosome evolves from a rigid and stimulation-insensitive to a more flexible and stimulation-responding complex.

To obtain the influence of anisotropy and energy evolution characteristics on wellbore stability, the acoustic and mechanical anisotropy characteristics of shales are studied through various experiments, including scanning electron microscopy, ultrasonic pulse transmission, and uniaxial compression experiments, with the Longmaxi Formation shale in the southern area of the Sichuan Basin as the research object. The energy evolution characteristics of the Longmaxi Formation shale under different bedding angles are analyzed. The influence of anisotropy on the wellbore stability of shale formation is discussed on this basis. The results show that the acoustic and mechanical parameters, failure mode, and energy evolution characteristics of shale have significant anisotropy. Furthermore, the P-wave and S-wave time differences decrease with an increase in bedding angle. The compressive strength and Poisson's ratio decrease first and then increase with an increase in bedding angle. Meanwhile, the elastic modulus gradually increases with an increase in bedding angle. Rock samples with different bedding angles show diverse failure modes in mechanical tests, including splitting, shear, and shear-splitting failure. The total energy and elastic energy decrease first and then increase with an increase in bedding angle. Finally, the formation anisotropy affects the wellbore stability: the higher the formation anisotropy, the more vulnerable is the wellbore to instability. [ABSTRACT FROM AUTHOR]

Tunable band gaps make two-dimensional (2D) SnO a promising candidate for a wide variety of applications in optoelectronic devices. In this work, we calculated the structural, electronic, and optical properties of monolayer and mutilayer SnO up to seven layers based on density functional theory. We found that the band gaps of SnO can vary from 0.61 eV to 4.05 eV as the layer number of SnO decreases from seven to one, which is mainly because of the interlayer coupling effect. The interlayer coupling ensures improved carrier transport properties between neighbouring layers, which can benefit the performance of 2D SnO in photovoltaic applications. In particular, a suitable band gap of 1.20 eV for solar cell applications is obtained in trilayer SnO, and the predicted theoretical efficiency of solar cells with trilayer SnO as the active material achieves a high value exceeding 16%, which is relatively high for 2D materials. [ABSTRACT FROM AUTHOR]

Deglucose chikusetsusaponin IVa (DCIVa), isolated from Rhizoma Panacis Majoris, a widely used traditional Chinese medicine, is a type of oleanane triterpenoids. Various previous studies have demonstrated that oleanane triterpenoids exhibit cytotoxic activity against various types of cancer cells. However, whether DCIVa exerts an antitumor effect remains to be elucidated. The present study aimed to assess the effect of DCIVa on cancer cells using the HepG2 hepatocellular carcinoma cell line and determine the underlying mechanism. Using an MTT assay, it was demonstrated that DCIVa inhibited cell growth and viability in a dose- and time-dependent manner. Typical apoptotic features, including chromatin condensation and margination at the nuclear periphery, and apoptotic body formation were induced by DCIVa and were detected by transmission electron microscopy. In addition, nuclear condensation and fragmentation were also observed by Hoechst 33258 staining. Furthermore, flow cytometric analysis revealed that DCIVa increased cell apoptosis and G2/M cell cycle arrest dose-dependently. Western blot analysis further demonstrated that DCIVa upregulated the expression of the pro-apoptotic protein, Bax, and downregulated the expression of the anti-apoptotic protein, Bcl-2. In conclusion, the present study demonstrated for the first time, to the best of our knowledge, that DCIVa exerts potent cytotoxic effects on HepG2 cells through induction of cell apoptosis and cell cycle arrest, and may be utilized as a potential anticancer agent. [ABSTRACT FROM AUTHOR]

The genus Kadsura is an important part of traditional Chinese medicine, it has the functions of promoting wind, eliminating dampness, activating blood circulation. Modern pharmacological studies have shown that lignans are one of the main components to possess these medicinal effects. This review aimed to provide a systematic summary on the traditional use, phytochemistry, pharmacology, toxicology and other aspects of lignans in genus Kadsura. In this paper, we collected the relevant literature on Kadsura lignans from 1973 to the present, and isolated more than 337 lignans from this genus, including dibenzocyclooctadienes, aryltetralins, tetrahydrofurans, diarylbutanes, 7,8-secolignans, bisepoxylignans, neolignans, seco-dibenzocyclooctadienes, sesquilignan and coumarin-containing lignan. Previous pharmacological studies have shown that lignans of the genus Kadsura have antitumor, anti-inflammatory, antibacterial, anti-HIV, anti-platelet aggregation, immunomodulatory and antioxidant effects. In clinical practice, it is commonly used to treat Alzheimer's disease, inflammation and insomnia. Kadsura is an important part of the field of Chinese medicine and is widely used in traditional medicine. However, further clarification of its active ingredients and mechanism of action and the establishment of a complete quality standard system are needed in order to provide a scientific basis for in-depth studies of this genus. [ABSTRACT FROM AUTHOR]

The basal chordate amphioxus is a model for tracing the origin and evolution of vertebrate immunity. To explore the evolution of immunoreceptor signaling pathways, we searched the associated receptors of the amphioxus Branchiostoma belcheri (Bb) homolog of immunoreceptor signaling adaptor protein Grb2. Mass-spectrum analysis of BbGrb2 immunoprecipitates from B. belcheri intestine lysates revealed a folate receptor (FR) domain- and leucine-rich repeat (LRR)-containing protein (FrLRR). Sequence and structural analysis showed that FrLRR is a membrane protein with a predicted curved solenoid structure. The N-terminal Fr domain contains very few folate-binding sites; the following LRR region is a Slit2-type LRR, and a GPI-anchored site was predicted at the C-terminus. RT-PCR analysis showed FrLRR is a transcription-mediated fusion gene of BbFR-like and BbSlit2-N-like genes. Genomic DNA structure analysis implied the B. belcheri FrLRR gene locus and the corresponding locus in Branchiostoma floridae might be generated by exon shuffling of a Slit2-N-like gene into an FR gene. RT-qPCR, immunostaining, and immunoblot results showed that FrLRR was primarily distributed in B. belcheri intestinal tissue. We further demonstrated that FrLRR localized to the cell membrane and lysosomes. Functionally, FrLRR mediated and promoted bacteria-binding and phagocytosis, and FrLRR antibody blocking or Grb2 knockdown inhibited FrLRR-mediated phagocytosis. Interestingly, we found that human Slit2-N (hSlit2-N) also mediated direct bacteria-binding and phagocytosis which was inhibited by Slit2-N antibody blocking or Grb2 knockdown. Together, these results indicate FrLRR and hSlit2-N may function as phagocytotic-receptors to promote phagocytosis through Grb2, implying the Slit2-N-type-LRRcontaining proteins play a role in bacterial binding and elimination. [ABSTRACT FROM AUTHOR]

The genus Kadsura is a commonly used herb in Chinese folklore, with sedative, hypnotic and beneficial effects, mainly for the treatment of rheumatoid arthritis, insomnia and other conditions. Modern pharmacological studies have shown that triterpenoids are one of the main components to possess these medicinal effects. In addition, triterpenoids in genus Kadsura also exhibited anti-tumor, cholesterol synthesis inhibition, anti-HIV, antioxidant and hepatoprotective activities. At present, there are few literatures reported on the triterpenoids in this genus. Therefore, the purpose of this paper is to review the triterpenoids in the genus Kadsura and their pharmacological activities, introduce the research progress on their germplasm resources, clinical applications and developmental applications, and provide references for further research and development of the plant resources of this genus. [ABSTRACT FROM AUTHOR]