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Objective To report 4 cases of intracranial arterial stenosis stenting via radial artery approach and summarize the experience of treatment. Methods and Results The clinical data and treatment process of 4 patients with ischemic stroke treated by intracranial arterial stenosis stenting via radial artery approach in The Affiliated Hospital of Qingdao University were reviewed in 2022. The stenoses were located in the initial segment of left internal carotid artery (ICA), the initial segment of right vertebral artery (VA), the V4 segment of left VA, and the junction of V4 segment of left VA and the basilar artery, respectively. All the 4 patients underwent transradial approach stenting for ICA stenosis. The surgery was successful and the stenoses were recanalized. No adverse reactions were observed during and after the surgery. Conclusions Intracranial arterial stenosis stenting via radial artery approach is safe and effective in the treatment of ischemic stroke.

The arthropod exoskeleton provides protection and support and is vital for survival and adaption. The integrity and mechanical properties of the exoskeleton are often impaired after pathogenic infection; however, the detailed mechanism by which infection affects the exoskeleton remains largely unknown. Here, we report that the damage to the shrimp exoskeleton is caused by modulation of host lipid profiles after infection with white spot syndrome virus (WSSV). WSSV infection disrupts the mechanical performance of the exoskeleton by inducing the expression of a chitinase (Chi2) in the sub-cuticle epidermis and decreasing the cuticle chitin content. The induction of Chi2 expression is mediated by a nuclear receptor that can be activated by certain enriched long-chain saturated fatty acids after infection. The damage to the exoskeleton, an aftereffect of the induction of host lipogenesis by WSSV, significantly impairs the motor ability of shrimp. Blocking the WSSV-caused lipogenesis restored the mechanical performance of the cuticle and improved the motor ability of infected shrimp. Therefore, this study reveals a mechanism by which WSSV infection modulates shrimp internal metabolism resulting in phenotypic impairment, and provides new insights into the interactions between the arthropod host and virus. Author summary: Loosening and softening of the exoskeleton of shrimp is frequently observed after white spot syndrome virus (WSSV) infection. This study reveals that the impairment of the exoskeleton is due to the enrichment of certain long-chain fatty acids (LCFAs), induction of chitinase, and ultimately decrease in cuticle chitin after WSSV infection. The exoskeleton allows for movement through contracting connected muscle; therefore, these WSSV-induced changes impair the motor ability of infected shrimp. The impaired motor ability may increase the chance of an infected shrimp being consumed by a healthy shrimp, thereby facilitating the natural transmission of WSSV. As WSSV exploits LCFAs for virion morphogenesis, we also show that blocking WSSV-induced lipogenesis restores exoskeleton performance, providing a possible strategy for the inhibition of viral transmission. [ABSTRACT FROM AUTHOR]

Given the limitations of manufacturing precision, manufacturing cost, and other factors, contact clearance is always inevitable at the contact interface of components. The contact clearance leads to the reduction of heat flux during the heat transfer process. The effect of thermal contact resistance is significant, particularly in the fields of aerospace, microelectrical technology, and cryogenic superconductor that are closely related to the operating temperature. The thermal contact resistance is affected by many factors, such as size, shape, space of asperity, mechanical properties of the material, external pressure, and temperature. Moreover, these factors usually interact with each other and need to be coupled. Thus, how to describe the thermal contact resistance accurately and build the appropriate prediction model are the key problems that should be resolved during engineering calculations. On the basis of the research results of domestic and international scholars, the current research state of thermal contact resistance during theoretical calculations and engineering applications were presented. The theoretical calculation, experimental measurement, and digital simulation methods used to analyze macroscopic thermal contact resistance were summarized, and the advantages and disadvantages of these methods were indicated. The effects of different factors on macroscopic thermal contact resistance were briefly discussed. On the basis of the combined cooling experiments of low-temperature superconducting magnet coils of the China Fusion Engineering Test Reactor, the effects of heat flow direction, temperature, and pressure on the thermal contact resistance of superconducting magnet components, such as stainless-steel jacket, dielectric insulation material, and quench protection material, were analyzed. Moreover, the reason why the effects of temperature and external pressure result in the change of thermal contact resistance was investigated from the perspective of thermal mechanics. Finally, given the accuracy and convenience requirements for the calculation of thermal contact resistance during engineering practice, the future research direction was indicated.

BACKGROUND: Since the 1990s, drylands have been extensively converted to rice paddy fields on the former wetlands in the Sanjiang Plain of northeast China. However, the influence of this successiveland‐use change from native wetlands to drylands to rice paddy fields on soil organic carbon (C) dynamics remains unexplored. Here, we compared the difference in soil organic C stock among native wetlands, drylands, and paddy fields, and then used a two‐step acid hydrolysis approach to examine the effect of this land‐use change on labile C I (LPI‐C), labile C II (LPII‐C), and recalcitrant C (RP‐C) fractions at depths of 0–15 cm, 15–30 cm, and 30–50 cm. RESULTS: Soil organic C stock at a depth of 0–50 cm was reduced by 79% after the conversion of wetlands to drylands but increased by 24% when drylands were converted to paddy fields. Compared with wetlands, paddy fields had 74% lower soil organic C stock at a depth of 0–50 cm. The conversion of wetlands to drylands reduced the concentrations of LPI‐C, LPII‐C, and RP‐C fractions at each soil depth. However, land‐use change from drylands to paddy fields only increased the concentrations of LPI‐C and LPII‐C fractions at the 0–15 cm and 30–50 cm depths. CONCLUSION: The conversion of drylands to paddy lands on former wetlands enhances the soil organic C stock by promoting labile C fraction accumulation, and labile C fractions are more sensitive to this successive land‐use change than recalcitrant C fractions in the Sanjiang Plain of northeast China. © 2022 Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

Small antibacterial effectors, including lysozymes, lectins, and antimicrobial peptides, are key regulators of intestinal immunity. However, whether there is coordination among them during regulation is an interesting, but largely unknown, issue. In the present study, we revealed that small effectors synergistically regulate peptidoglycan-derived intestinal immunity in the kuruma shrimp, Marsupenaeus japonicus. A C-type lysozyme (LysC) was screened as a responsive factor for the intestine-bacteria interaction. LysC functions to restrict intestinal bacteria, mainly by cleaving Photobacterium damselae peptidoglycan to generate muropeptides which are powerful stimulators that induce anti-lipopolysaccharides factor B1 (AlfB1), an effective bactericidal peptide. The muropeptides also induce a C-type lectin (Ctl24), which recognizes peptidoglycan and coats bacteria. By counteracting LysC-mediated muropeptide release and AlfB1's bactericidal activity, Ctl24 prevents the continuous elimination of intestinal bacteria. Therefore, this study demonstrates a mechanism by which small immune effectors coordinate to achieve intestinal homeostasis, and provides new insights into peptidoglycan-derived intestinal immunity in invertebrates. Author summary: Intestinal homeostasis largely determines the healthy status of metazoan animals. Uncovering the mechanism for intestinal homeostasis would be helpful to develop new strategies for disease control. In this study, we demonstrated that small immune effectors, including lysozyme, lectin, and bactericidal peptide, collaborate to regulate shrimp intestinal homeostasis in shrimp. Intestinal bacterial peptidoglycan is digested by a lysozyme into muropeptides, which induce the expression of this lysozyme, a bactericidal peptide and a lectin. The former two effectors are able to restrict intestinal bacteria by generating muropeptides and killing bacteria, respectively, while the latter one counteracts their functions. By coating peptidoglycan, this lectin inhibits lysozyme-mediated muropeptides release, and bactericidal peptide-mediated killing of bacteria. Through controlling, but not eliminating intestinal bacteria, these small effectors together achieve a dynamic balance of intestinal bacteria in shrimp. Therefore, this study emphasized the significance of peptidoglycan as the driving force for intestinal homeostasis, and provides insights into generating a healthy intestinal microbiota by utilizing the synergy among small immune effectors. [ABSTRACT FROM AUTHOR]

Flagellin is a key bacterial virulence factor that can stimulate molecular immune signaling in both animals and plants. The detailed mechanisms of recognizing flagellin and mounting an efficient immune response have been uncovered in vertebrates; however, whether invertebrates can discriminate flagellin remains largely unknown. In the present study, the homolog of human SHOC2 leucine rich repeat scaffold protein in kuruma shrimp (Marsupenaeus japonicus), designated MjShoc2, was found to interact with Vibrio anguillarum flagellin A (FlaA) using yeast two-hybrid and pull-down assays. MjShoc2 plays a role in antibacterial response by mediating the FlaA-induced expression of certain antibacterial effectors, including lectin and antimicrobial peptide. FlaA challenge, via MjShoc2, led to phosphorylation of extracellular regulated kinase (Erk), and the subsequent activation of signal transducer and activator of transcription (Stat), ultimately inducing the expression of effectors. Therefore, by establishing the FlaA/MjShoc2/Erk/Stat signaling axis, this study revealed a new antibacterial strategy in shrimp, and provides insights into the flagellin sensing mechanism in invertebrates. Author summary: Flagellin sensing has been proven as a general antibacterial strategy. Recognition of bacterial flagellin by the transmembrane receptor toll like receptor 5 (TLR5) leads to the activation of nuclear factor kappa B (NF-κB) pathway and induction of proinflammatory cytokines, while recognition by the intracellular nucleotide-binding leucine-rich (NLR) receptor leads to caspase-activation and cytokines-expression. Although flagellin is an effective immune stimulator that induces antimicrobial peptides in Drosophila and in crustaceans, how an invertebrate host senses flagellin and mounts an immune response is poorly understood. Here, we used the flagellin (FlaA) from Vibrio anguillarum, a pathogen of shrimp, as a bait protein to screen a yeast two-hybrid library derived from kuruma shrimp (Marsupenaeus japonicus). We found a scaffold protein, MjShoc2, able to interact with FlaA. We also found that FlaA could effectively induce the expression of certain recognized antibacterial effectors in shrimp depending on MjShoc2. We revealed that extracellular regulated kinase (Erk) phosphorylation occurred downstream of FlaA/MjShoc2, and led to signal transducer and activator of transcription (Stat) activation, resulting in transcription of certain effectors. Therefore our study provides new insights into the FlaA-induced molecular immunity in invertebrates. [ABSTRACT FROM AUTHOR]

Aims Climate warming and increasing nitrogen (N) deposition have influenced plant nutrient status and thus plant carbon (C) fixation and vegetation composition in boreal peatlands. Phenols, which are secondary metabolites in plants for defense and adaptation, also play important roles in regulating peatland C dynamics due to their anti-decomposition properties. However, how the phenolic levels of different functional types of plants vary depending on nutrient availability remain unclear in boreal peatlands. Methods Here, we investigated total phenols contents (TPC) and total tannins contents in leaves of 11 plant species in 18 peatlands of the Great Hing'an Mountains area in northeastern China, and examined their variations with leaf N and phosphorus (P) and underlying mechanisms. Important Findings Shrubs had higher TPC than graminoids, indicating less C allocation to defense and less uptake of organic N in faster-growing and nonmycorrhizal graminoids than in slower-growing and mycorrhizal shrubs. For shrubs, leaf TPC decreased with increasing N contents but was not influenced by changing leaf phosphorus (P) contents, which suggested that shrubs would reduce the C investment for defense with increasing N availability. Differently, leaf TPC of graminoids increased with leaf N contents and decreased with leaf P contents. As graminoids are more N-limited and less P-limited, we inferred that graminoids would increase the defensive C investment under increased nutrient availability. We concluded that shrubs would invest more C in growth than in defense with increasing N availability, but it was just opposite for graminoids, which might be an important mechanism to explain the resource competition and encroachment of shrubs in boreal peatlands in the context of climate warming and ever-increasing N deposition. [ABSTRACT FROM AUTHOR]