Black holes regulate cool gas accretion in massive galaxies.

The nucleus of almost all massive galaxies contains a supermassive black hole (BH)1. The feedback from the accretion of these BHs is often considered to have crucial roles in establishing the quiescence of massive galaxies2-14, although some recent studies show that even galaxies hosting the most active BHs do not exhibit a reduction in their molecular gas reservoirs or star formation rates15-17. Therefore, the influence of BHs on galaxy star formation remains highly debated and lacks direct evidence. Here, based on a large sample of nearby galaxies with measurements of masses of both BHs and atomic hydrogen (HI), the main component of the interstellar medium18, we show that the HI gas mass to stellar masses ratio (µHI = MHI/M⋆) is more strongly correlated with BH masses (MBH) than with any other galaxy parameters, including stellar mass, stellar mass surface density and bulge masses. Moreover, once the µHI-MBH correlation is considered, µHI loses dependence on other galactic parameters, demonstrating that MBH serves as the primary driver of µHI. These findings provide important evidence for how the accumulated energy from BH accretion regulates the cool gas content in galaxies, by ejecting interstellar medium gas and/or suppressing gas cooling from the circumgalactic medium.

Subsecond periodic radio oscillations in a microquasar.

Powerful relativistic jets are one of the ubiquitous features of accreting black holes in all scales1-3. GRS 1915 + 105 is a well-known fast-spinning black-hole X-ray binary4 with a relativistic jet, termed a 'microquasar', as indicated by its superluminal motion of radio emission5,6. It has exhibited persistent X-ray activity over the last 30 years, with quasiperiodic oscillations of approximately 1-10 Hz (refs. 7-9) and 34 and 67 Hz in the X-ray band10. These oscillations probably originate in the inner accretion disk, but other origins have been considered11. Radio observations found variable light curves with quasiperiodic flares or oscillations with periods of approximately 20-50 min (refs. 12-14). Here we report two instances of approximately 5-Hz transient periodic oscillation features from the source detected in the 1.05- to 1.45-GHz radio band that occurred in January 2021 and June 2022. Circular polarization was also observed during the oscillation phase.

A ring-like accretion structure in M87 connecting its black hole and jet.

The nearby radio galaxy M87 is a prime target for studying black hole accretion and jet formation1,2. Event Horizon Telescope observations of M87 in 2017, at a wavelength of 1.3 mm, revealed a ring-like structure, which was interpreted as gravitationally lensed emission around a central black hole3. Here we report images of M87 obtained in 2018, at a wavelength of 3.5 mm, showing that the compact radio core is spatially resolved. High-resolution imaging shows a ring-like structure of [Formula: see text] Schwarzschild radii in diameter, approximately 50% larger than that seen at 1.3 mm. The outer edge at 3.5 mm is also larger than that at 1.3 mm. This larger and thicker ring indicates a substantial contribution from the accretion flow with absorption effects, in addition to the gravitationally lensed ring-like emission. The images show that the edge-brightened jet connects to the accretion flow of the black hole. Close to the black hole, the emission profile of the jet-launching region is wider than the expected profile of a black-hole-driven jet, suggesting the possible presence of a wind associated with the accretion flow.

Transgenic ferret models define pulmonary ionocyte diversity and function.

Speciation leads to adaptive changes in organ cellular physiology and creates challenges for studying rare cell-type functions that diverge between humans and mice. Rare cystic fibrosis transmembrane conductance regulator (CFTR)-rich pulmonary ionocytes exist throughout the cartilaginous airways of humans1,2, but limited presence and divergent biology in the proximal trachea of mice has prevented the use of traditional transgenic models to elucidate ionocyte functions in the airway. Here we describe the creation and use of conditional genetic ferret models to dissect pulmonary ionocyte biology and function by enabling ionocyte lineage tracing (FOXI1-CreERT2::ROSA-TG), ionocyte ablation (FOXI1-KO) and ionocyte-specific deletion of CFTR (FOXI1-CreERT2::CFTRL/L). By comparing these models with cystic fibrosis ferrets3,4, we demonstrate that ionocytes control airway surface liquid absorption, secretion, pH and mucus viscosity-leading to reduced airway surface liquid volume and impaired mucociliary clearance in cystic fibrosis, FOXI1-KO and FOXI1-CreERT2::CFTRL/L ferrets. These processes are regulated by CFTR-dependent ionocyte transport of Cl- and HCO3-. Single-cell transcriptomics and in vivo lineage tracing revealed three subtypes of pulmonary ionocytes and a FOXI1-lineage common rare cell progenitor for ionocytes, tuft cells and neuroendocrine cells during airway development. Thus, rare pulmonary ionocytes perform critical CFTR-dependent functions in the proximal airway that are hallmark features of cystic fibrosis airway disease. These studies provide a road map for using conditional genetics in the first non-rodent mammal to address gene function, cell biology and disease processes that have greater evolutionary conservation between humans and ferrets.

Steric pressure between glycosylated transmembrane proteins inhibits internalization by endocytosis.

Clathrin-mediated endocytosis is essential for the removal of transmembrane proteins from the plasma membrane in all eukaryotic cells. Many transmembrane proteins are glycosylated. These proteins collectively comprise the glycocalyx, a sugar-rich layer at the cell surface, which is responsible for intercellular adhesion and recognition. Previous work has suggested that glycosylation of transmembrane proteins reduces their removal from the plasma membrane by endocytosis. However, the mechanism responsible for this effect remains unknown. To study the impact of glycosylation on endocytosis, we replaced the ectodomain of the transferrin receptor, a well-studied transmembrane protein that undergoes clathrin-mediated endocytosis, with the ectodomain of MUC1, which is highly glycosylated. When we expressed this transmembrane fusion protein in mammalian epithelial cells, we found that its recruitment to endocytic structures was substantially reduced in comparison to a version of the protein that lacked the MUC1 ectodomain. This reduction could not be explained by a loss of mobility on the cell surface or changes in endocytic dynamics. Instead, we found that the bulky MUC1 ectodomain presented a steric barrier to endocytosis. Specifically, the peptide backbone of the ectodomain and its glycosylation each made steric contributions, which drove comparable reductions in endocytosis. These results suggest that glycosylation constitutes a biophysical signal for retention of transmembrane proteins at the plasma membrane. This mechanism could be modulated in multiple disease states that exploit the glycocalyx, from cancer to atherosclerosis.

Lipid droplets as substrates for protein phase separation.

Membrane-associated protein phase separation plays critical roles in cell biology, driving essential cellular phenomena from immune signaling to membrane traffic. Importantly, by reducing dimensionality from three to two dimensions, lipid bilayers can nucleate phase separation at far lower concentrations compared with those required for phase separation in solution. How might other intracellular lipid substrates, such as lipid droplets, contribute to nucleation of phase separation? Distinct from bilayer membranes, lipid droplets consist of a phospholipid monolayer surrounding a core of neutral lipids, and they are energy storage organelles that protect cells from lipotoxicity and oxidative stress. Here, we show that intrinsically disordered proteins can undergo phase separation on the surface of synthetic and cell-derived lipid droplets. Specifically, we find that the model disordered domains FUS LC and LAF-1 RGG separate into protein-rich and protein-depleted phases on the surfaces of lipid droplets. Owing to the hydrophobic nature of interactions between FUS LC proteins, increasing ionic strength drives an increase in its phase separation on droplet surfaces. The opposite is true for LAF-1 RGG, owing to the electrostatic nature of its interprotein interactions. In both cases, protein-rich phases on the surfaces of synthetic and cell-derived lipid droplets demonstrate molecular mobility indicative of a liquid-like state. Our results show that lipid droplets can nucleate protein condensates, suggesting that protein phase separation could be key in organizing biological processes involving lipid droplets.

Guanylate binding protein 5 triggers NF-κB activation to foster radioresistance, metastatic progression and PD-L1 expression in oral squamous cell carcinoma.

Radioresistance and metastasis are critical issues in managing oral squamous cell carcinoma (OSCC). Although immune checkpoint inhibitors (ICIs) has been recommended to treat OSCC, lacking useful biomarkers limited their anti-cancer effectiveness. We found that guanylate binding protein 5 (GBP5) is upregulated in primary tumors and associates with radioresistance in OSCC. GBP5 expression causally associated with cellular radioresistance and migration ability in the OSCC cell variants. GBP5 upregulation was examined to be correlated with NF-κB activation and programmed cell death-ligand 1 (PD-L1) elevation in OSCC samples. GBP5 knockdown was mitigated, but overexpression enhanced, NF-κB activity and PD-L1 expression in the OSCC cells. NF-κB inhibition by SN50 dramatically suppressed the GBP5-forested irradiation resistance, cellular migration ability and PD-L1 expression in OSCC cells. Importantly, GBP5 upregulation predicted a favorable outcome in cancer patients received ICI treatment. Our findings provide GBP5 as a useful biomarker to predict the anti-OSCC effectiveness of irradiation and ICIs.

Integrin αV mediated activation of myofibroblast via mechanoparacrine of transforming growth factor ß1 in promoting fibrous scar formation after myocardial infarction.

BACKGROUND: Myocardial infarction (MI) dramatically changes the mechanical stress, which is intensified by the fibrotic remodeling. Integrins, especially the αV subunit, mediate mechanical signal and mechanoparacrine of transforming growth factor ß1 (TGF-ß1) in various organ fibrosis by activating CFs into myofibroblasts (MFBs). We investigated a possible role of integrin αV mediated mechanoparacrine of TGF-ß1 in MFBs activation for fibrous reparation in mice with MI. METHODS: Heart samples from MI, sham, or MI plus cilengitide (14 mg/kg, specific integrin αV inhibitor) treated mice, underwent functional and morphological assessments by echocardiography, and histochemistry on 7, 14 and 28 days post-surgery. The mechanical and ultrastructural changes of the fibrous scar were further evaluated by atomic mechanics microscope (AFM), immunofluorescence, second harmonic generation (SHG) imaging, polarized light and scanning electron microscope, respectively. Hydroxyproline assay was used for total collagen content, and western blot for protein expression profile examination. Fibroblast bioactivities, including cell shape, number, Smad2/3 signal and expression of extracellular matrix (ECM) related proteins, were further evaluated by microscopic observation and immunofluorescence in polyacrylamide (PA) hydrogel with adjustable stiffness, which was re-explored in fibroblast cultured on stiff matrix after silencing of integrin αV. The content of total and free TGF-ß1 was tested by enzyme-linked immunosorbent assay (ELISA) in both infarcted tissue and cell samples. RESULT: Increased stiffness with heterogeneity synchronized with integrin αV and alpha smooth muscle actin (α-SMA) positive MFBs accumulation in those less mature fibrous areas. Cilengitide abruptly reduced collagen content and disrupted collagen alignment, which also decreased TGF-ß1 bioavailability, Smad2/3 phosphorylation, and α-SMA expression in the fibrous area. Accordingly, fibroblast on stiff but not soft matrix exhibited obvious MFB phenotype, as evidenced by enlarged cell, hyperproliferation, well-developed α-SMA fibers, and elevated ECM related proteins, while silencing of integrin αV almost abolished this switch via attenuating paracrine of TGF-ß1 and nuclear translocation of Smad2/3. CONCLUSION: This study illustrated that increased tissue stiffness activates CFs into MFBs by integrin αV mediated mechanoparacrine of TGF-ß1, especially in immature scar area, which ultimately promotes fibrous scar maturation.

AIM2 promotes irradiation resistance, migration ability and PD-L1 expression through STAT1/NF-κB activation in oral squamous cell carcinoma.

BACKGROUND: Radioresistance and lymph node metastasis are common phenotypes of refractory oral squamous cell carcinoma (OSCC). As a result, understanding the mechanism for radioresistance and metastatic progression is urgently needed for the precise management of refractory OSCC. Recently, immunotherapies, e.g. immune checkpoint inhibitors (ICIs), were employed to treat refractory OSCC; however, the lack of predictive biomarkers still limited their therapeutic effectiveness. METHODS: The Cancer Genome Atlas (TCGA)/Gene Expression Omnibus (GEO) databases and RT-PCR analysis were used to determine absent in melanoma 2 (AIM2) expression in OSCC samples. Colony-forming assay and trans-well cultivation was established for estimating AIM2 function in modulating the irradiation resistance and migration ability of OSCC cells, respectively. RT-PCR, Western blot and flow-cytometric analyses were performed to examine AIM2 effects on the expression of programmed death-ligand 1 (PD-L1) expression. Luciferase-based reporter assay and site-directed mutagenesis were employed to determine the transcriptional regulatory activity of Signal Transducer and Activator of Transcription 1 (STAT1) and NF-κB towards the AIM2-triggered PD-L1 expression. RESULTS: Here, we found that AIM2 is extensively upregulated in primary tumors compared to the normal adjacent tissues and acts as a poor prognostic marker in OSCC. AIM2 knockdown mitigated, but overexpression promoted, radioresistance, migration and PD-L1 expression via modulating the activity of STAT1/NF-κB in OSCC cell variants. AIM2 upregulation significantly predicted a favorable response in patients receiving ICI treatments. CONCLUSIONS: Our data unveil AIM2 as a critical factor for promoting radioresistance, metastasis and PD-L1 expression and as a potential biomarker for predicting ICI effectiveness on the refractory OSCC.

Pepsin-mediated inflammation in laryngopharyngeal reflux via the ROS/NLRP3/IL-1ß signaling pathway.

BACKGROUND: Laryngopharyngeal reflux (LPR) is one of the most common disorders in otorhinolaryngology, affecting up to 10% of outpatients visiting otolaryngology departments. In addition, 50% of hoarseness cases are related to LPR. Pepsin reflux-induced aseptic inflammation is a major trigger of LPR; however, the underlying mechanisms are unclear. The nucleotide-binding domain and leucine-rich repeat protein 3 (NLRP3) inflammasome has become an important bridge between stimulation and sterile inflammation and is activated by intracellular reactive oxygen species (ROS) in response to danger signals, leading to an inflammatory cascade. In this study, we aimed to determine whether pepsin causes LPR-associated inflammatory injury via mediating inflammasome activation and explore the potential mechanism. METHODS: We evaluated NLRP3 inflammasome expression and ROS in the laryngeal mucosa using immunofluorescence and immunohistochemistry. Laryngeal epithelial cells were exposed to pepsin and analyzed using flow cytometry, western blotting, and real-time quantitative PCR to determine ROS, NLRP3, and pro-inflammatorycytokine levels. RESULTS: Pepsin expression was positively correlated with ROS as well as caspase-1 and IL-1ß levels in laryngeal tissues. Intracellular ROS levels were elevated by increased pepsin concentrations, which were attenuated by apocynin (APO)-a ROS inhibitor-in vitro. Furthermore, pepsin significantly induced the mRNA and protein expression of thioredoxin-interacting protein, NLRP3, caspase-1, and IL-1ß in a dose-dependent manner. APO and the NLRP3 inhibitor, MCC950, inhibited NLRP3 inflammasome formation and suppressed laryngeal epithelial cell damage. CONCLUSION: Our findings verified that pepsin could regulate the NLRP3/IL-1ß signaling pathway through ROS activation and further induce inflammatory injury in LPR. Targeting the ROS/NLRP3 inflammasome signaling pathway may help treat patients with LPR disease.

Genomic analysis of hypoxia-tolerant population of the Chinese mitten crab (Eriocheir sinensis).

Hypoxic stress, triggered by a multitude of factors, has inflicted significant economic repercussions on the aquaculture of Eriocheir sinensis. In this research, we sequenced a collective of 60 samples from both hypoxia-sensitive and hypoxia-resistant groups utilizing streamlined genome sequencing techniques. Subsequently, we delved into population evolution, scrutinized the selective sweep within these populations, and performed a genome-wide association study (GWAS) focused on the hypoxia tolerance traits within the population, all through the lens of SNPs molecular markers. This comprehensive analysis aimed to uncover the SNPs and pinpoint the pertinent candidate genes that influence the hypoxia tolerance capabilities of E. sinensis. The selective sweep analysis revealed that genes harboring potential genetic variations within the two populations were predominantly enriched in areas such as signaling molecules and interactions, energy metabolism, glycolipid metabolism, and immune response. In the genome-wide association study focusing on hypoxia tolerance traits, we identified four SNPs significantly associated with hypoxia resistance. Furthermore, one potential candidate gene, Dscam2, which is believed to influence hypoxia tolerance, was discovered within a 50 kb vicinity of these SNPs. These identified SNPs can serve as molecular markers for screening hypoxia tolerance, offering valuable insights for the genetic improvement of E. sinensis.

A revised airway epithelial hierarchy includes CFTR-expressing ionocytes.

The airways of the lung are the primary sites of disease in asthma and cystic fibrosis. Here we study the cellular composition and hierarchy of the mouse tracheal epithelium by single-cell RNA-sequencing (scRNA-seq) and in vivo lineage tracing. We identify a rare cell type, the Foxi1+ pulmonary ionocyte; functional variations in club cells based on their location; a distinct cell type in high turnover squamous epithelial structures that we term 'hillocks'; and disease-relevant subsets of tuft and goblet cells. We developed 'pulse-seq', combining scRNA-seq and lineage tracing, to show that tuft, neuroendocrine and ionocyte cells are continually and directly replenished by basal progenitor cells. Ionocytes are the major source of transcripts of the cystic fibrosis transmembrane conductance regulator in both mouse (Cftr) and human (CFTR). Knockout of Foxi1 in mouse ionocytes causes loss of Cftr expression and disrupts airway fluid and mucus physiology, phenotypes that are characteristic of cystic fibrosis. By associating cell-type-specific expression programs with key disease genes, we establish a new cellular narrative for airways disease.

Inflammatory Activity of Epithelial Stem Cell Variants from Cystic Fibrosis Lungs Is Not Resolved by CFTR Modulators.

Rationale: CFTR (cystic fibrosis transmembrane conductance regulator) modulator drugs restore function to mutant channels in patients with cystic fibrosis (CF) and lead to improvements in body mass index and lung function. Although it is anticipated that early childhood treatment with CFTR modulators will significantly delay or even prevent the onset of advanced lung disease, lung neutrophils and inflammatory cytokines remain high in patients with CF with established lung disease despite modulator therapy, underscoring the need to identify and ultimately target the sources of this inflammation in CF lungs. Objectives: To determine whether CF lungs, like chronic obstructive pulmonary disease (COPD) lungs, harbor potentially pathogenic stem cell "variants" distinct from the normal p63/Krt5 lung stem cells devoted to alveolar fates, to identify specific variants that might contribute to the inflammatory state of CF lungs, and to assess the impact of CFTR genetic complementation or CFTR modulators on the inflammatory variants identified herein. Methods: Stem cell cloning technology developed to resolve pathogenic stem cell heterogeneity in COPD and idiopathic pulmonary fibrosis lungs was applied to end-stage lungs of patients with CF (three homozygous CFTR:F508D, one CFTR F508D/L1254X; FEV1, 14-30%) undergoing therapeutic lung transplantation. Single-cell-derived clones corresponding to the six stem cell clusters resolved by single-cell RNA sequencing of these libraries were assessed by RNA sequencing and xenografting to monitor inflammation, fibrosis, and mucin secretion. The impact of CFTR activity on these variants after CFTR gene complementation or exposure to CFTR modulators was assessed by molecular and functional studies. Measurements and Main Results: End-stage CF lungs display a stem cell heterogeneity marked by five predominant variants in addition to the normal lung stem cell, of which three are proinflammatory both at the level of gene expression and their ability to drive neutrophilic inflammation in xenografts in immunodeficient mice. The proinflammatory functions of these three variants were unallayed by genetic or pharmacological restoration of CFTR activity. Conclusions: The emergence of three proinflammatory stem cell variants in CF lungs may contribute to the persistence of lung inflammation in patients with CF with advanced disease undergoing CFTR modulator therapy.

Membrane bending by protein phase separation.

Membrane bending is a ubiquitous cellular process that is required for membrane traffic, cell motility, organelle biogenesis, and cell division. Proteins that bind to membranes using specific structural features, such as wedge-like amphipathic helices and crescent-shaped scaffolds, are thought to be the primary drivers of membrane bending. However, many membrane-binding proteins have substantial regions of intrinsic disorder which lack a stable three-dimensional structure. Interestingly, many of these disordered domains have recently been found to form networks stabilized by weak, multivalent contacts, leading to assembly of protein liquid phases on membrane surfaces. Here we ask how membrane-associated protein liquids impact membrane curvature. We find that protein phase separation on the surfaces of synthetic and cell-derived membrane vesicles creates a substantial compressive stress in the plane of the membrane. This stress drives the membrane to bend inward, creating protein-lined membrane tubules. A simple mechanical model of this process accurately predicts the experimentally measured relationship between the rigidity of the membrane and the diameter of the membrane tubules. Discovery of this mechanism, which may be relevant to a broad range of cellular protrusions, illustrates that membrane remodeling is not exclusive to structured scaffolds but can also be driven by the rapidly emerging class of liquid-like protein networks that assemble at membranes.

Association of MRI findings with paraspinal muscles fat infiltration at lower lumbar levels in patients with chronic low back pain: a multicenter prospective study.

OBJECTIVE: In chronic low back pain (CLBP), the relationship between spinal pathologies and paraspinal muscles fat infiltration remains unclear. This study aims to evaluate the relationship between MRI findings and paraspinal muscles morphology and fat infiltration in CLBP patients by quantitative MRI. METHODS: All the CLBP patients were enrolled from July 2021 to December 2022 in four medical institutions. The cross-sectional area (CSA) and proton density fat fraction (PDFF) of the multifidus (MF) and erector spinae (ES) muscles at the central level of the L4/5 and L5/S1 intervertebral discs were measured. MRI findings included degenerative lumbar spondylolisthesis (DLS), intervertebral disc degeneration (IVDD), facet arthrosis, disc bulge or herniation, and disease duration. The relationship between MRI findings and the paraspinal muscles PDFF and CSA in CLBP patients was analyzed. RESULTS: A total of 493 CLBP patients were included in the study (198 females, 295 males), with an average age of 45.68 ± 12.91 years. Our research indicates that the number of MRI findings are correlated with the paraspinal muscles PDFF at the L4/5 level, but is not significant. Moreover, the grading of IVDD is the primary factor influencing the paraspinal muscles PDFF at the L4-S1 level (BES at L4/5=1.845, P < 0.05); DLS was a significant factor affecting the PDFF of MF at the L4/5 level (B = 4.774, P < 0.05). After including age, gender, and Body Mass Index (BMI) as control variables in the multivariable regression analysis, age has a significant positive impact on the paraspinal muscles PDFF at the L4-S1 level, with the largest AUC for ES PDFF at the L4/5 level (AUC = 0.646, cut-off value = 47.5), while males have lower PDFF compared to females. BMI has a positive impact on the ES PDFF only at the L4/5 level (AUC = 0.559, cut-off value = 24.535). CONCLUSION: The degree of paraspinal muscles fat infiltration in CLBP patients is related to the cumulative or synergistic effects of multiple factors, especially at the L4/L5 level. Although age and BMI are important factors affecting the degree of paraspinal muscles PDFF in CLBP patients, their diagnostic efficacy is moderate.

Integration of 3D printing and case-based learning in clinical practice for the treatment of developmental dysplasia of the hip.

BACKGROUND: Case-based learning (CBL) utilizing three-dimensional (3D) printed hip joint models is a problem-solving teaching method that combines the tactile and visual advantages of 3D-printed models with CBL. This study aims to investigate the impact of integrating 3D printing with CBL on learning developmental dysplasia of the hip (DDH). METHODS: We conducted a prospective study from 2022 to 2023, including 120 fourth-year clinical medical students at Xuzhou Medical University. Students were randomly allocated into two groups of 60 participants each. The CBL group received conventional CBL teaching methods, while the 3D + CBL group utilized 3D-printed models in conjunction with CBL. Post-teaching, we analyzed and compared the theoretical and practical achievements of both groups. A questionnaire was designed to assess the impact of the educational approach on orthopedic surgery learning. RESULTS: The theory scores of the CBL group (62.88 ± 7.98) and 3D + CBL group (66.35 ± 8.85) were significantly different (t = 2.254, P = 0.026); the practical skills scores of the CBL group (57.40 ± 8.80) and 3D + CBL group (63.42 ± 11.14) were significantly different (t = 3.283, P = 0.001). The questionnaire results showed that the 3D + CBL group was greater than the CBL group in terms of hip fundamentals, ability to diagnose cases and plan treatments, interesting teaching content, willingness to communicate with the instructor and satisfaction. CONCLUSIONS: The integration of 3D printing with case-based learning has yielded positive outcomes in teaching DDH, providing valuable insights into the use of 3D-printed orthopedic models in clinical education.

PriTKT: A Blockchain-Enhanced Privacy-Preserving Electronic Ticket System for IoT Devices.

Electronic tickets (e-tickets) are gradually being adopted as a substitute for paper-based tickets to bring convenience to customers, corporations, and governments. However, their adoption faces a number of practical challenges, such as flexibility, privacy, secure storage, and inability to deploy on IoT devices such as smartphones. These concerns motivate the current research on e-ticket systems, which seeks to ensure the unforgeability and authenticity of e-tickets while simultaneously protecting user privacy. Many existing schemes cannot fully satisfy all these requirements. To improve on the current state-of-the-art solutions, this paper constructs a blockchain-enhanced privacy-preserving e-ticket system for IoT devices, dubbed PriTKT, which is based on blockchain, structure-preserving signatures (SPS), unlinkable redactable signatures (URS), and zero-knowledge proofs (ZKP). It supports flexible policy-based ticket purchasing and ensures user unlinkability. According to the data minimization and revealing principle of GDPR, PriTKT empowers users to selectively disclose subsets of (necessary) attributes to sellers as long as the disclosed attributes satisfy ticket purchasing policies. In addition, benefiting from the decentralization and immutability of blockchain, effective detection and efficient tracing of double spending of e-tickets are supported in PriTKT. Considering the impracticality of existing e-tickets schemes with burdensome ZKPs, we replace them with URS/SPS or efficient ZKP to significantly improve the efficiency of ticket issuing and make it suitable for use on smartphones.

Reversible, Covalent DNA Condensation Approach Using Chemical Linkers for Enhanced Gene Delivery.

Nonviral gene delivery has emerged as a promising technology for gene therapy. Nonetheless, these approaches often face challenges, primarily associated with lower efficiency, which can be attributed to the inefficient transportation of DNA into the nucleus. Here, we report a two-stage condensation approach to achieve efficient nuclear transport of DNA. First, we utilize chemical linkers to cross-link DNA plasmids via a reversible covalent bond to form smaller-sized bundled DNA (b-DNA). Then, we package the b-DNA into cationic vectors to further condense b-DNA and enable efficient gene delivery to the nucleus. We demonstrate clear improvements in the gene transfection efficiency in vitro, including with 11.6 kbp plasmids and in primary cultured neurons. Moreover, we also observed a remarkable improvement in lung-selective gene transfection efficiency in vivo by this two-stage condensation approach following intravenous administration. This reversible covalent assembly strategy demonstrates substantial value of nonviral gene delivery for clinical therapeutic applications.

Bioactive polysaccharides in different plant parts of Aconitum carmichaelii.

BACKGROUND: Aconitum carmichaelii is an industrially cultivated medicinal plant in China and its lateral and mother roots are used in traditional Chinese medicine due to the presence of alkaloids. However, the rootlets and aerial parts are discarded after collection of the roots, and the non-toxic polysaccharides in this plant have attracted less attention than the alkaloids and poisonous features. In this study, five neutral and 14 acidic polysaccharide fractions were isolated systematically from different plant parts of A. carmichaelii, and their structural features and bioactivity were studied and compared. RESULTS: The neutral fraction isolated from the rootlets differed from those isolated from the lateral and mother roots. It consisted of less starch and more possible mannans, galactans, and/or xyloglucans, being similar to those of the aerial parts. Pectic polysaccharides containing homogalacturonan and branched type-I rhamnogalacturonan (RG-I) were present in all plant parts of A. carmichaelii. However, more arabinogalactan (AG)-II side chains in the RG-I backbone were present in the aerial parts of the plants, while more amounts of arabinans were found in the roots. Various immunomodulatory effects were observed, determined by complement fixation activity and anti-inflammatory effects on the intestinal epithelial cells of all polysaccharide fractions. CONCLUSION: This study highlighted the diversity of polysaccharides present in A. carmichaelii, especially in the unutilized plant parts, and showed their potential medicinal value. © 2023 The Authors. Journal of The Science of Food and Agriculture published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.

Sub-Nanosheet Induced Inverse Growth of Negative Valency Au Clusters for Tumor Treatment by Enhanced Oxidative Stress.

Cluster aggregation states are thermodynamically favored at the subnanoscale, for which an inverse growth from nanoparticles to clusters may be realized on subnanometer supports. Herein, we develop Au-polyoxometalate-layered double hydroxide (Au-POM-LDH) sub-1 nm nanosheets (Sub-APL) based on the above strategy, where sub-1 nm Au clusters with negative valence are generated by the in situ disintegration of Au nanoparticles on POM-LDH supports. Sub-1 nm Au clusters with ultrahigh surface atom ratios exhibit remarkable efficiency for glutathione (GSH) depletion. The closely connected sub-1 nm Au with negative valence and POM hetero-units can promote the separation of hole-electrons, resulting in the enhanced reactive oxygen species (ROS) generation under ultrasound (US). Besides, the reversible redox of Mo in POM is able to deplete GSH and trigger chemodynamic therapy (CDT) simultaneously, further enhancing the oxidative stress. Consequently, the Sub-APL present 2-fold ROS generation under US and 7-fold GSH depletion compared to the discrete Au and POM-LDH mixture. Therefore, the serious imbalance of redox in the TME caused by the sharp increase of ROS and rapid decrease of GSH leads to death of tumor ultimately.