peri-Fused polyaromatic molecular contacts for perovskite solar cells.

Molecule-based selective contacts have become a crucial component to ensure high-efficiency inverted perovskite solar cells1-5. These molecules always consist of a conjugated core with heteroatom substitution to render the desirable carrier-transport capability6-9. So far, the design of successful conjugation cores has been limited to two N-substituted π-conjugated structures, carbazole and triphenylamine, with molecular optimization evolving around their derivatives2,5,10-12. However, further improvement of the device longevity has been hampered by the concomitant limitations of the molecular stability induced by such heteroatom-substituted structures13,14. A more robust molecular contact without sacrificing the electronic properties is in urgent demand, but remains a challenge. Here we report a peri-fused polyaromatic core structure without heteroatom substitution that yields superior carrier transport and selectivity over conventional heteroatom-substituted core structures. This core structure produced a relatively chemically inert and structurally rigid molecular contact, which considerably improved the performance of perovskite solar cells in terms of both efficiency and durability. The champion device showed an efficiency up to 26.1% with greatly improved longevity under different accelerated-ageing tests.

Sum rule comparison of narrowband and broadband sum frequency generation spectra and comparison with theory.

Earlier sum frequency generation (SFG) experiments involve one infrared and one visible laser, and a measurement of the intensity of the response, yielding data on the surface sensitive properties of the sample. Recently, both the real and imaginary components of the susceptibility were measured in two different sets of experiments. In one set, a broadband infrared laser was used, permitting observations at very short times, while in another set the infrared laser was narrowband, permitting higher spectral resolution. The differences in the spectrum obtained by the two will be most evident in studying narrow absorption bands, e.g., the band due to dangling OH bonds at a water interface. The direct comparisons in the integrated amplitude (sum rule) of the imaginary part of the dangling OH bond region differ by a factor of 3. Due to variations in experimental setup and data processing, corrections were made for the quartz reference, Fresnel factors, and the incident visible laser wavelength. After the corrections, the agreement differs now by the factors of 1.1 within broadband and narrowband groups and the two groups now differ by a factor of 1.5. The 1.5 factor may arise from the extra heating of the more powerful broadband laser system on the water surface. The convolution from the narrowband SFG spectrum to the broadband SFG spectrum is also investigated and it does not affect the sum rule. Theory and narrowband experiments are compared using the sum rule and agree to a factor of 1.3 with no adjustable parameters.

Deubiquitinase USP1 regulates sarbecovirus ORF6 protein function.

SARS-CoV-2 belongs to the subgenus Sarbecovirus, which universally encodes the accessory protein ORF6. SARS-CoV-2 ORF6 is an antagonist of the interferon (IFN)-mediated antiviral response and plays an important role in viral infections. However, the mechanism by which the host counteracts the function of ORF6 to restrict viral replication remains unclear. In this study, we found that most ORF6 proteins encoded by sarbecoviruses could be ubiquitinated and subsequently degraded via the proteasome pathway. Through extensive screening, we identified that the deubiquitinase USP1, which effectively and broadly deubiquitinates sarbecovirus ORF6 proteins, stabilizes ORF6 proteins, resulting in enhanced viral replication. Therefore, ubiquitination and deubiquitination of ORF6 are important for antagonizing IFN-mediated antiviral signaling and influencing the virulence of SARS-CoV-2. These findings highlight an essential molecular mechanism and may provide a novel target for therapeutic interventions against viral infections.IMPORTANCEThe ORF6 proteins encoded by sarbecoviruses are essential for effective viral replication and infection and are important targets for developing effective intervention strategies. In this study, we confirmed that sarbecovirus ORF6 proteins are important antagonists of the host immune response and identified the regulatory mechanisms of ubiquitination and deubiquitination of most sarbecovirus ORF6 proteins. Moreover, we revealed that DUB USP1 prevents the proteasomal degradation of all ORF6 proteins, thereby promoting the virulence of SARS-CoV-2. Thus, impeding ORF6 function is helpful for attenuating the virulence of sarbecoviruses. Therefore, our findings provide a deeper understanding of the molecular mechanisms underlying sarbecovirus infections and offer potential new therapeutic targets for the prevention and treatment of these infections.

Growth Process of Fe-O Nanoclusters with Different Sizes Biosynthesized by Protein Nanocages.

All protein-directed syntheses of metal nanoclusters (NCs) and nanoparticles (NPs) have attracted considerable attention because protein scaffolds provide a unique metal coordination environment and can adjust the shape and morphology of NCs and NPs. However, the detailed formation mechanisms of NCs or NPs directed by protein templates remain unclear. In this study, by taking advantage of the ferritin nanocage as a biotemplate to monitor the growth of Fe-O NCs as a function of time, we synthesized a series of iron NCs with different sizes and shapes and subsequently solved their corresponding three-dimensional atomic-scale structures by X-ray protein crystallography and cryo-electron microscopy. The time-dependent structure analyses revealed the growth process of these Fe-O NCs with the 4-fold channel of ferritin as nucleation sites. To our knowledge, the newly biosynthesized Fe35O23Glu12 represents the largest Fe-O NCs with a definite atomic structure. This study contributes to our understanding of the formation mechanism of iron NCs and provides an effective method for metal NC synthesis.

Ferroptosis-related lncRNA NRAV affects the prognosis of hepatocellular carcinoma via the miR-375-3P/SLC7A11 axis.

Ferroptosis has important value in cancer treatment. It is significant to explore the new ferroptosis-related lncRNAs prediction model in Hepatocellular carcinoma (HCC) and the potential molecular mechanism of ferroptosis-related lncRNAs. We constructed a prognostic multi-lncRNA signature based on ferroptosis-related differentially expressed lncRNAs in HCC. qRT-PCR was applied to determine the expression of lncRNA in HCC cells. The biological roles of NRAV in vitro and in vivo were determined by performing a series of functional experiments. Furthermore, dual-luciferase reporter and RNA immunoprecipitation (RIP) assays were used to confirm the interaction of NRAV with miR-375-3P. We identified 6 differently expressed lncRNAs associated with the prognosis of HCC. Kaplan-Meier analyses revealed the high-risk lncRNAs signature associated with poor prognosis of HCC. Moreover, the AUC of the lncRNAs signature showed utility in predicting HCC prognosis. Further functional experiments show that the high expression of NRAV can strengthen the viciousness of HCC. Interestingly, we found that NRAV can enhance iron export and ferroptosis resistance. Further study showed that NRAV competitively binds to miR-375-3P and attenuates the inhibitory effect of miR-375-3P on SLC7A11, affecting the prognosis of patients with HCC. In conclusion, We developed a novel ferroptosis-related lncRNAs prognostic model with important predictive value for the prognosis of HCC. NRAV is important in ferroptosis induction through the miR-375-3P/SLC7A11 axis.

Discovery of a novel small molecule as CD47/SIRPα and PD-1/PD-L1 dual inhibitor for cancer immunotherapy.

BACKGROUND: Targeting the tumor microenvironment (TME) has emerged as a promising strategy in cancer treatment, particularly through the utilization of immune checkpoint blockade (ICB) agents such as PD-1/PD-L1 inhibitors. Despite partial success, the presence of tumor-associated macrophages (TAMs) contributes to an immunosuppressive TME that fosters tumor progression, and diminishes the therapeutic efficacy of ICB. Blockade of the CD47/SIRPα pathway has proven to be an effective intervention, that restores macrophage phagocytosis and yields substantial antitumor effects, especially when combined with PD-1/PD-L1 blockade. Therefore, the identification of small molecules capable of simultaneously blocking CD47/SIRPα and PD-1/PD-L1 interactions has remained imperative. METHODS: SMC18, a small molecule with the capacity of targeting both SIRPα and PD-L1 was obtained using MST. The efficiency of SMC18 in interrupting CD47/SIRPα and PD-1/PD-L1 interactions was tested by the blocking assay. The function of SMC18 in enhancing the activity of macrophages and T cells was tested using phagocytosis assay and co-culture assay. The antitumor effects and mechanisms of SMC18 were investigated in the MC38-bearing mouse model. RESULTS: SMC18, a small molecule that dual-targets both SIRPα and PD-L1 protein, was identified. SMC18 effectively blocked CD47/SIRPα interaction, thereby restoring macrophage phagocytosis, and disrupted PD-1/PD-L1 interactions, thus activating Jurkat cells, as evidenced by increased secretion of IL-2. SMC18 demonstrated substantial inhibition of MC38 tumor growths through promoting the infiltration of CD8+ T and M1-type macrophages into tumor sites, while also priming the function of CD8+ T cells and macrophages. Moreover, SMC18 in combination with radiotherapy (RT) further improved the therapeutic efficacy. CONCLUSION: Our findings suggested that the small molecule compound SMC18, which dual-targets the CD47/SIRPα and PD-1/PD-L1 pathways, could be a candidate for promoting macrophage- and T-cell-mediated phagocytosis and immune responses in cancer immunotherapy.

Synthesis, structure, spectra, cytotoxicity and photo induced NO release of four isomeric nitrosylruthenium complexes.

Four isomeric nitrosyl ruthenium complexes [RuCl(2mqn)(Val)(NO)] (1-4) were prepared (2mqn, 2-methyl-8-hydroxyquinoline; Val, l-valine) and characterized by 1H NMR, 13C NMR, absorption spectrum, electrospray ionization mass spectrometry, and X-ray crystal diffraction. Time-resolved FT-IR and fluorescence spectroscopy were used to monitor photo-induced NO release in solution, while NO released in living cells was imaged using a selective fluorescent probe. The isomeric complexes showed different levels of cytotoxicity against HeLa cells, and slightly photo-enhanced anti-proliferative activity was observed. The isomeric complexes 1-4 inhibited the growth of HeLa cells by inducing apoptosis and promoted cell cycle arrest in the S phase. Furthermore, they showed relatively lower cytotoxicity against the human liver cell line HL-7702. The different spatial configurations of the complexes is close related with the selective binding of the isomeric complexes with serum albumin, which provide insight into the potential applications of the nitrosyl ruthenium complexes.

Pseudo-Second-Order Kinetic Equation for Describing the Effect of Sorbent and Sorbate Concentrations.

The sorbent concentration (Cs) effect and sorbate initial concentration (C0) effect are common phenomena observed in the study of adsorption kinetics at solid-liquid interfaces. That is, adsorption rate constants simulated with classical kinetic equations, such as the pseudo-second-order (PSO) model, for a given system vary with Cs and C0. The classical kinetic equations cannot predict or describe the "Cs-effect" and "C0-effect" (called "C-effects" here). In the current work, the dynamic partition coefficient of sorbate between solid and liquid phases (Kt) was used to describe the adsorption kinetic processes. Based on the surface component activity (SCA) model, which assumes the activity coefficients of the surface components (fs) are not equal to unity but rather a function of Cs and the adsorption capacity (or C0) and referring to the classical PSO model, a new kinetic equation was established, called the "SCA-PSO kinetic model", and its two parameters, the intrinsic equilibrium partition coefficient (Ke0) and the intrinsic rate constant (k20), are independent of Cs and C0. In addition, the new model relates Kt and the rate constant (k2) to Cs and C0 via fs, and can thus describe the C-effects. The fs can be estimated from the change of equilibrium partition coefficient (Ke) with Cs and C0. The new model predicts that with the increase of Cs and C0, Ke decreases while k2 increases. Its rationality was confirmed by the literature-reported adsorption kinetic data of heavy metals on inorganic and biomass sorbents with the C-effects.

LINC00330/CCL2 axis-mediated ESCC TAM reprogramming affects tumor progression.

BACKGROUND: Tumor-associated macrophages (TAMs) significantly influence the progression, metastasis, and recurrence of esophageal squamous cell carcinoma (ESCC). The aberrant expression of long noncoding RNAs (lncRNAs) in ESCC has been established, yet the role of lncRNAs in TAM reprogramming during ESCC progression remains largely unexplored. METHODS: ESCC TAM-related lncRNAs were identified by intersecting differentially expressed lncRNAs with immune-related lncRNAs and performing immune cell infiltration analysis. The expression profile and clinical relevance of LINC00330 were examined using the TCGA database and clinical samples. The LINC00330 overexpression and interference sequences were constructed to evaluate the effect of LINC00330 on ESCC progression. Single-cell sequencing data, CIBERSORTx, and GEPIA were utilized to analyze immune cell infiltration within the ESCC tumor microenvironment and to assess the correlation between LINC00330 and TAM infiltration. ESCC-macrophage coculture experiments were conducted to investigate the influence of LINC00330 on TAM reprogramming and its subsequent effect on ESCC progression. The interaction between LINC00330 and C-C motif ligand 2 (CCL2) was confirmed through transcriptomic sequencing, subcellular localization analysis, RNA pulldown, silver staining, RNA immunoprecipitation, and other experiments. RESULTS: LINC00330 is significantly downregulated in ESCC tissues and strongly associated with poor patient outcomes. Overexpression of LINC00330 inhibits ESCC progression, including proliferation, invasion, epithelial-mesenchymal transition, and tumorigenicity in vivo. LINC00330 promotes TAM reprogramming, and LINC00330-mediated TAM reprogramming inhibits ESCC progression. LINC00330 binds to the CCL2 protein and inhibits the expression of CCL2 and downstream signaling pathways. CCL2 is critical for LINC00330-mediated TAM reprogramming and ESCC progression. CONCLUSIONS: LINC00330 inhibited ESCC progression by disrupting the CCL2/CCR2 axis and its downstream signaling pathways in an autocrine fashion; and by impeding CCL2-mediated TAM reprogramming in a paracrine manner. The new mechanism of TAM reprogramming mediated by the LINC00330/CCL2 axis may provide potential strategies for targeted and immunocombination therapies for patients with ESCC.

Response of seed germination, seedling growth and physiological characteristics to alkali stress in halophyte Suaeda liaotungensis.

Soil salinization has been considered as a major environmental threat to plant growth. Different types of salt in saline soil have different effects on germination and seedling growth. Effect of NaCl on germination and seedling establishment in Suaeda liaotungensis have been reported, but its response to alkali stress remains unclear. Our results showed that brown seeds had higher germination rate, however, black seeds had higher germination recovery percentage under alkali stress. Na2CO3 had stronger inhibitory effect on germination and seedling growth than NaHCO3. As the concentration of alkali stress increased, the ROS level of brown seeds gradually ascended, while that of black seeds decreased first and then ascended. MDA content of dimorphic seeds significantly increased under alkali stress. The trend of SOD, POD and CAT activity between dimorphic seeds was similar under the same type of alkali stress. Alkali stress enhanced proline content of dimorphic seeds, and dimorphic seeds in NaHCO3 solution had higher proline content than Na2CO3 solution. Moreover, radicle and shoot tolerance indexes of seedlings in NaHCO3 solution were significantly higher than that of Na2CO3 solution. Under strong alkali stress, seedlings in NaHCO3 solution had significantly lower ROS level and MDA content as well as higher antioxidant enzyme activity than Na2CO3 solution. This study comprehensively compared the morphological and physiological characteristics in germination and seedlings to better reveal the saline-alkali tolerance mechanisms in S. liaotungensis.

Jujuboside B alleviates acetaminophen-induced hepatotoxicity in mice by regulating Nrf2-STING signaling pathway.

BACKGROUND: Jujuboside B (JuB) is the main bioactive saponin component of Chinese anti-insomnia herbal medicine Ziziphi Spinosae Semen, which has been reported to possess varied pharmacological functions. Even though it has been traditionally used to treat inflammation- and toxicity-related diseases, the effects of JuB on acetaminophen (APAP) overdose-induced hepatotoxicity have not been determined yet. METHODS: C57BL/6 J mice were pre-treated with JuB (20 or 40 mg/kg) for seven days before APAP (400 mg/kg) injection. After 24 h of APAP treatment, serum, and liver tissues were collected to evaluate the therapeutic effects. To investigate whether the Nrf2-STING signaling pathway is involved in the protective effects of JuB against APAP-induced hepatotoxicity, the mice received the DMXAA (the specific STING agonist) or ML385 (the specific Nrf2 inhibitor) during the administration of JuB, and Hematoxylin-eosin staining, Real-time PCR, immunohistochemical, and western blot were performed. RESULTS: JuB pretreatment reversed APAP-induced CYP2E1 accumulations and alleviated APAP-induced acute liver injury. Furthermore, JuB treatment significantly inhibited oxidative stress and the pro-inflammatory cytokines, as well as alleviated hepatocyte apoptosis induced by APAP. Besides, our result also demonstrated that JuB treatment upregulated the levels of total Nrf2, facilitated its nuclear translocation, upregulated the expression of HO-1 and NQO-1, and inhibited the APAP-induced STING pathway activation. Finally, we verified that the beneficial effects of JuB were weakened by DMXAA and ML385. CONCLUSION: Our study suggested that JuB could ameliorate APAP-induced hepatic damage and verified a previously unrecognized mechanism by which JuB prevented APAP-induced hepatotoxicity through adjusting the Nrf2-STING pathway.

Transcriptome analysis reveals the mechanism of antifungal peptide epinecidin-1 against Botrytis cinerea by mitochondrial dysfunction and oxidative stress.

The marine antifungal peptide epinecidin-1 (EPI) have been shown to inhibit Botrytis cinerea growth, while the molecular mechanism have not been explored based on omics technology. This study aimed to investigate the molecular mechanism of EPI against B. cinerea by transcriptome technology. Our findings indicated that a total of 1671 differentially expressed genes (DEGs) were detected in the mycelium of B. cinerea treated with 12.5 µmol/L EPI for 3 h, including 773 up-regulated genes and 898 down-regulated genes. Cluster analysis showed that DEGs (including steroid biosynthesis, (unsaturated) fatty acid biosynthesis) related to cell membrane metabolism were significantly down-regulated, and almost all DEGs involved in DNA replication were significantly inhibited. In addition, it also induced the activation of stress-related pathways, such as the antioxidant system, ATP-binding cassette transporter (ABC) and MAPK signaling pathways, and interfered with the tricarboxylic acid (TCA) cycle and oxidative phosphorylation pathways related to mitochondrial function. The decrease of mitochondrial related enzyme activities (succinate dehydrogenase, malate dehydrogenase and adenosine triphosphatase), the decrease of mitochondrial membrane potential and the increase content of hydrogen peroxide further confirmed that EPI treatment may lead to mitochondrial dysfunction and oxidative stress. Based on this, we speculated that EPI may impede the growth of B. cinerea through its influence on gene expression, and may lead to mitochondrial dysfunction and oxidative stress.

Influence of flavonoids from Sedum aizoon L. on mitochondrial function of Rhizopus nigricans in strawberry.

Rhizopus nigricans (R. nigricans), one of the fungi that grows the fastest, is frequently discovered in postharvest fruits, it's the main pathogen of strawberry root rot. Flavonoids in Sedum aizoon L. (FSAL) is a kind of green and safe natural substance extracted from Sedum aizoon L. which has antifungal activity. In this study, the minimum inhibitory concentration (MIC) of FSAL on R. nigricans and cell apoptosis tests were studied to explore the inhibitory effect of FSAL on R. nigricans. The effects of FSAL on mitochondria of R. nigricans were investigated through the changes of mitochondrial permeability transition pore(mPTP), mitochondrial membrane potential(MMP), Ca2+ content, H2O2 content, cytochrome c (Cyt c) content, the related enzyme activity and related genes of mitochondria. The results showed that the MIC of FSAL on R. nigricans was 1.800 mg/mL, with the addition of FSAL (1.800 mg/mL), the mPTP openness of R. nigricans increased and the MMP reduced. Resulting in an increase in Ca2+ content, accumulation of H2O2 content and decrease of Cyt c content, the activity of related enzymes was inhibited and related genes were up-regulated (VDAC1, ANT) or down-regulated (SDHA, NOX2). This suggests that FSAL may achieve the inhibitory effect of fungi by damaging mitochondria, thereby realizing the postharvest freshness preservation of strawberries. This lays the foundation for the development of a new plant-derived antimicrobial agent.

Nanomicellar Electrolyte To Control Release Ions and Reconstruct Hydrogen Bonding Network for Ultrastable High-Energy-Density Zn-Mn Battery.

Zn-Mn batteries with two-electron conversion reactions simultaneously on the cathode and anode harvest a high voltage plateau and high energy density. However, the zinc anode faces dendrite growth and parasitic side reactions while the Mn2+/MnO2 reaction on the cathode involves oxygen evolution and possesses poor reversibility. Herein, a novel nanomicellar electrolyte using methylurea (Mu) has been developed that can encapsulate ions in the nanodomain structure to guide the homogeneous deposition of Zn2+/Mn2+ in the form of controlled release under an external electric field. Consecutive hydrogen bonding network is broken and a favorable local hydrogen bonding system is established, thus inhibiting the water-splitting-derived side reactions. Concomitantly, the solid-electrolyte interface protective layer is in situ generated on the Zn anode, further circumventing the corrosion issue resulting from the penetration of water molecules. The reversibility of the Mn2+/MnO2 conversion reaction is also significantly enhanced by regulating interfacial wettability and improving nucleation kinetics. Accordingly, the modified electrolyte endows the symmetric Zn∥Zn cell with extended cyclic stability of 800 h with suppressed dendrites growth at an areal capacity of 1 mAh cm-2. The assembled Zn-Mn electrolytic battery also demonstrates an exceptional capacity retention of nearly 100% after 800 cycles and a superior energy density of 800 Wh kg-1 at an areal capacity of 0.5 mAh cm-2.

Polo-like kinase 1 promotes pulmonary hypertension.

BACKGROUND: Pulmonary hypertension (PH) is a lethal vascular disease with limited therapeutic options. The mechanistic connections between alveolar hypoxia and PH are not well understood. The aim of this study was to investigate the role of mitotic regulator Polo-like kinase 1 (PLK1) in PH development. METHODS: Mouse lungs along with human pulmonary arterial smooth muscle cells and endothelial cells were used to investigate the effects of hypoxia on PLK1. Hypoxia- or Sugen5416/hypoxia was applied to induce PH in mice. Plk1 heterozygous knockout mice and PLK1 inhibitors (BI 2536 and BI 6727)-treated mice were checked for the significance of PLK1 in the development of PH. RESULTS: Hypoxia stimulated PLK1 expression through induction of HIF1α and RELA. Mice with heterozygous deletion of Plk1 were partially resistant to hypoxia-induced PH. PLK1 inhibitors ameliorated PH in mice. CONCLUSIONS: Augmented PLK1 is essential for the development of PH and is a druggable target for PH.

Correlations of Surface Free Energy and Solubility Parameter with Dielectric Constant and Density for Inorganic Solids.

There should be some intrinsic correlations between the surface free energy (γ) and solubility (δ) parameters, called characteristic parameters here, of substances with their basic physical properties such as the relative dielectric constant (εr) and density (ρ), because they are all related to intermolecular interactions. Several correlations have been proposed empirically (or semiempirically) for liquids, but not for solids. It is essential to establish such correlations for solids because the estimation of γ and δ for solids is difficult and/or time-consuming. In the current work, the γ, δ, εr, and ρ data of 34 inorganic solids were chosen, and possible relationships between the characteristic parameters (γ and δ) and the physical quantities (εr and ρ) were explored by a trial-and-error fitting method based on the data of the solids. Six equations relating γ and δ to εr and δ were established. The γ parameters include total (γt), dispersive (γd), and polar (γp) ones, and the δ parameters include the Hildebrand parameter (δt) and the Hansen-dispersive (δd), polar (δp), and hydrogen-bonding (δh) ones. The empirical equations can be used to estimate the characteristic parameters of inorganic solids from their easily measurable physical quantities.

Investigation of the Multimechanism Laser Cleaning Dynamics for Rough Fused Silica Surfaces with Organic Contaminants: A Computational Simulation and Atomic Analysis.

The detrimental impact of organic contaminants on optical components poses a significant obstacle to high-energy laser systems. However, irregularities or defects on the surface of optical components during manufacturing can affect the process of organic contaminant removal. Thus, a comprehensive understanding of the intricate interplay among surface roughness, contaminant absorption, and ablation is essential to effectively address the challenges of laser-induced damage. In this study, a molecular dynamics approach was employed to investigate the interaction between laser-fused silica and contaminants and to analyze the influence of surface roughness on the removal of contaminants from fused silica. Research findings demonstrate that during laser irradiation, organic contaminants on the surface of mechanical components diffuse into the optical elements. As the laser flux increases, the contaminants gradually decompose into smaller molecular clusters. Additionally, the phenomenon of contaminant ablation is observed to consist of two distinct phases: the "Thermal expansion phase" and the "Thermal ablation phase." The study examines the impact of substrate roughness on the contaminant removal in these two phases. It is found that a higher surface roughness leads to stronger thermal expansion and vaporization of contaminants. With increasing roughness of the fused silica substrate, the corresponding van der Waals energy and pressure decrease under the same laser fluence, making the removal of contaminants easier. These results provide valuable insights into the interaction between laser irradiation and organic contaminants.

Luteimonas suaedae sp. nov., a novel bacterium isolated from rhizosphere of Suaeda aralocaspica (Bunge) Freitag & Schütze.

Light yellowish-white colonies of a bacterial strain, designated LNNU 24178T, were isolated from the rhizosphere soil of halophyte Suaeda aralocaspica (Bunge) Freitag and Schütze grown at Shihezi district, Xinjiang, PR China. Cells were Gram-stain-negative, non-flagellum-forming, rod-shaped and non-motile. The results of phylogenetic analysis based on the 16S rRNA gene sequence indicated that LNNU 24178T represented a member of the genus Luteimonas and shared the highest sequence similarity with Luteimonas yindakuii CGMCC 1.13927T (97.1 %) and lower sequence similarity (< 97.0 %) to other known species. The genomic DNA G+C content of LNNU 24178T was 68.8 %. The average nucleotide identity (ANI) values between LNNU 24178T and Luteimonas yindakuii CGMCC 1.13927T, Luteimonas mephitis DSM 12574T, Luteimonas arsenica 26-35T and Luteimonas huabeiensis HB2T were 78.7, 78.6, 78.4 and 80.0 %, respectively. The digital DNA-DNA hybridisation (dDDH) values between LNNU 24178T and L. yindakuii CGMCC 1.13927T, L. mephitis DSM 12574T, L. arsenica 26-35T and L. huabeiensis HB2T were 22.0, 22.3, 22.2 and 23.5 %, respectively. The respiratory quinone detected in LNNU 24178T was ubiquinone-8 (Q-8). The major fatty acids (> 5.0 %) of LNNU 24178T were identified as iso-C15 : 0 (33.9 %), iso-C17 : 0 (8.7 %), iso-C11 : 0 (6.2 %), iso-C16 : 0 (5.7 %), C16 : 0 (5.3 %) and summed feature 9 (iso-C17 : 1ω9c/10-methyl C16 : 0) (21.1 %). The major polar lipids of LNNU 24178T were diphosphatidylglycerol (DPG), phosphatidylglycerol (PG), phosphatidylethanolamine (PE), one unidentified phospholipid (PL), one unidentified glycolipid (GL) and three unidentified lipids. According to the data obtained from phenotypic, chemotaxonomic and phylogenetic analyses, strain LNNU 24178T represents a novel species of the genus Luteimonas, for which the name Luteimonas suaedae sp. nov. is proposed, with LNNU 24178T (= CGMCC 1.17331T= KCTC 62251T) as the type strain.

Retrievable Inferior Vena Cava Filter Trapped Embolus: A Risk Factor of Detachment of Thrombus Analysis Based on a Multicenter Prospective Observational Study.

PURPOSE: Up to now, the indications of inferior vena cava filter placement still remain controversial in the academic field. The aim of this study was to determine the risk factors of detachment of thrombus and to evaluate the necessity of inferior vena cava filter placement to prevent fatal pulmonary embolism. MATERIALS AND METHODS: A total of 2892 patients participated in the multicenter prospective observational study from January 1, 2018, to December 31, 2018, and underwent retrievable inferior vena cava filter (RIVCF) placement in 103 centers in China. The primary endpoint of the study was RIVCF trapped embolus detected by inferior vena cava venography/ultrasound/computed tomography scanning or visible macroscopic thrombus before or during RIVCF retrieval. The relative factors of RIVCF trapped embolus were analyzed accordingly. RESULTS: The average age of the patients was 61.0 (50.0-71.0) years. Retrievable inferior vena cava filter trapped embolus occurred in 308 patients (10.65%). The fracture location, surgery location, and endovascular intervention differed between RIVCF trapped embolus and non-RIVCF trapped embolus groups (p<0.001, respectively). By multivariate analysis, RIVCF trapped embolus were less common in older patients (odds ratio [OR]=0.998; p<0.001) and more common in patients with below-the-knee fracture (OR=1.093, p=0.038), thigh fracture (OR=1.118, p=0.007), and pelvis surgery (OR=1.067, p=0.016). In addition, compared with patients without endovascular intervention, patients with percutaneous mechanical thrombectomy (PMT) + catheter-directed thrombolysis (CDT) were more prone to develop RIVCF trapped embolus (OR=1.060, p=0.010). However, RIVCF trapped embolus was less common in patients with CDT (OR=0.961, p=0.004). CONCLUSIONS: Lower limb fracture, pelvis surgery, and PMT + CDT are prone to cause trapped embolus. As a trapped embolus often represents the possibility of severe pulmonary embolism, lower limb fracture, pelvis surgery, and PMT + CDT could be risk factors of fatal pulmonary embolism. Due to the low incidence of trapped embolus, it is not necessary to place filters in elderly patients and CDT-only patients. CLINICAL IMPACT: The purpose of this paper is to standardize the use of inferior vena cava filter and avoid unnecessary filter implantation through the summary and analysis of a large number of clinical data. At the same time, more attention should be paid to and active treatment should be given to high-risk groups of pulmonary embolism.

Influences of flavonoids from Sedum aizoon L. on biofilm formation of Pseudomonas fragi.

Pseudomonas fragi (P. fragi) is one of the main categories of bacteria responsible for the spoilage of chilled meat. In the processing and preservation of chilled meat, it is easy to form biofilms on the meat, leading to the development of slime on the meat, which becomes a major quality defect. Flavonoids, as one of the critical components of secondary plant metabolites, are receiving increasing attention for their antibacterial activity. Flavonoids in Sedum aizoon L. (FSAL), relying on its prominent antibacterial activity, are of research importance in food preservation and other applications. This article aims to investigate the effect of FSAL on the biofilm formation of P. fragi, to better apply FSAL to the processing and preservation of meat products. The disruption of cellular structure and aggregation properties by FSAL was demonstrated by the observation of the cellular state within the biofilm. The amount of biofilm formation was determined by crystal violet staining, and the content of polysaccharides and proteins in the extracellular wrapped material was determined. It was shown that the experimental concentrations of FSAL (1.0 MIC) was able to inhibit biofilm formation and reduce the main components in the extracellular secretion. The swimming motility assay and the downregulation of flagellin-related genes confirmed that FSAL reduced cell motility and adhesion. The downregulation of cell division genes and the lowering of bacterial metabolic activity suggested that FSAL could hinder bacterial growth and reproduction within P. fragi biofilms. KEY POINTS: • FSAL inhibited the activity of Pseudomonas fragi in the dominant meat strain • The absence of EPS components affected the formation of P. fragi biofilms • P. fragi has reduced adhesion capacity due to impaired flagellin function.