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Hypothesis Lung surfactant protects lung tissue and reduces the surface tension in the alveoli during respiration. Particulate matter with an aerodynamic diameter of less than 2.5 μm (PM2.5), which invades primely through inhalation, can deposit on and interact with the surfactant layer, leading to changes in the biophysical and morphological properties of the lung surfactant. Experiments Langmuir monolayers of 1,2-dipalmitoyl-sn-glycero-3-phosphatidylcholine (DPPC) and clinical surfactant Calsurf were investigated with a PM2.5 model injected into the water subphase, which were characterized by surface pressure-area isotherms, Brewster angle microscopy, atomic force microscopy, fluorescent microscopy, and x-ray photoelectron spectroscopy. The binding between DPPC/Calsurf and PM2.5 was studied using isothermal titration calorimetry. Findings PM2.5 induced the expansion of the monolayers at low surface pressure (п) and film condensation at high п. Aggregation of PM2.5 mainly occurred at the interface of liquid expanded/liquid condensed (LE/LC) phases. PM2.5 led to slimmer and ramified LC domains on DPPC and the reduction of nano-sized condensed domains on Calsurf. Both DPPC and Calsurf showed fast binding with PM2.5 through complex binding modes attributed to the heterogeneity and amphiphilic property of PM2.5. This study improves the fundamental understanding of PM2.5-lung surfactant interaction and shows useful implications of the toxicity of PM2.5 through respiration process.

Developing effective internal wound dressing materials is important for postoperative tissue regeneration while remains a challenge due to the poor biological environment-adaptability of conventional materials. Here, we report an example of injectable self-healing hydrogel based on gastric environment-adaptive supramolecular assembly, and have explored its application for gastric perforation healing. By leveraging the gastric environment-modulated supramolecular interactions, the self-assembled hydrogel network is orchestrated with sensitive thermo-responsibility, injectability, printability and rapid self-healing capability. The hydrogel dressing can effectively inhibit the attachment of microorganisms and demonstrates outstanding antibiofouling property. In vivo rat model further demonstrates the as-prepared hydrogel dressing simplifies the surgical procedures, reduces postoperative complications as well as enhances the healing process of gastric perforation compared with the conventional treatment. This work provides useful insights into the development of biological environment-adaptive functional materials for various biomedical applications.

The use of hematoma expansion (HE) in intracerebral hemorrhage (ICH) patients is limited due to its low sensitivity. Perihematomal edema (PHE) has been considered an important marker of secondary brain injury after ICH. Enrolling PHE expansion to redefine traditional ICH expansion merits exploration.This study analyzed a cohort of patients with spontaneous ICH. The hematoma and PHE were manually segmented. Logistic regression analysis was utilized to identify risk factors for poor outcomes. Receiver operating characteristic curve analysis was performed to calculate the predictive values of PHE expansion and HE. Poor neurological outcome was defined as a modified Rankin Scale score of 4-6 at 90 days.Overall, 223 target patients were enrolled in the study. Multivariable analysis showed the larger PHE expansion is the independent risk factors for poor prognosis. The predictive value of absolute PHE expansion (AUC=0.776, sensitivity=67.9%, specificity=77.0%) was higher than that of absolute HE (AUC=0.573, sensitivity=41.7%, specificity=87.1%) and HE (6 ml) (AUC=0.594, sensitivity=23.8%, specificity=95.0%). The best cutoff for early absolute/relative PHE expansion resulting in a poor outcome was 5.96 ml and 31%.Early PHE expansion was associated with a poor outcome, characterized by a better predictive value than HE.

Theranostic platforms that combine therapy with diagnosis not only prevent the undesirable biological responses that may occur when these processes are conducted separately, but also allow individualized therapies for patients. Polymer hydrogels have been employed to provide well-controlled drug release and targeted therapy in theranostics, where injectable hydrogels enable non-invasive treatment and monitoring with a single injection, offering greater patient comfort and efficient therapy. Efforts have been focused on applying injectable polymer hydrogels in theranostic research and clinical use. This review highlights recent progress in the design of injectable polymer hydrogels for cancer theranostics, particularly focusing on the elements/components of theranostic hydrogels, and their cross-linking strategies, structures, and performance with regard to drug delivery/tracking. Therapeutic agents and tracking modalities that are essential components of the theranostic platforms are introduced, and the design strategies, properties and applications of the injectable hydrogels developed via two approaches, namely chemical bonds and physical interactions, are described. The theranostic functions of the platforms are highly dependent on the architecture and components employed for the construction of hydrogels. Challenges currently presented by theranostic platforms based on injectable hydrogels are identified, and prospects of acquiring more comfortable and personalized therapies are proposed.

The SARS-CoV-2 virus that causes the COVID-19 epidemic can be transmitted via respiratory droplet-contaminated surfaces or fomites, which urgently requires a fundamental understanding of intermolecular interactions of the coronavirus with various surfaces. The corona-like component of the outer surface of the SARS-CoV-2 virion, named spike protein, is a key target for the adsorption and persistence of SARS-CoV-2 on various surfaces. However, a lack of knowledge in intermolecular interactions between spike protein and different substrate surfaces has resulted in ineffective preventive measures and inaccurate information. Herein, we quantified the surface interaction and adhesion energy of SARS-CoV-2 spike protein with a series of inanimate surfaces via atomic force microscopy under a simulated respiratory droplet environment. Among four target surfaces, polystyrene was found to exhibit the strongest adhesion, followed by stainless steel (SS), gold, and glass. The environmental factors (e.g., pH and temperature) played a role in mediating the spike protein binding. According to systematic quantification on a series of inanimate surfaces, the adhesion energy of spike protein was found to be (i) 0–1 mJ/m2 for hydrophilic inorganics (e.g., silica and glass) due to the lack of hydrogen bonding, (ii) 2–9 mJ/m2 for metals (e.g., alumina, SS, and copper) due to the variation of their binding capacity, and (iii) 6–11 mJ/m2 for hydrophobic polymers (e.g., medical masks, safety glass, and nitrile gloves) due to stronger hydrophobic interactions. The quantitative analysis of the nanomechanics of spike proteins will enable a protein–surface model database for SARS-CoV-2 to help generate effective preventive strategies to tackle the epidemic.

In this contribution, carbon quantum dots (CQDs) modified 3D-flower like BiOX (X = Cl, Br, I) photocatalyst were successfully prepared via a facile mechanical compounding method. The crystal structure, surface composition, morphologies, optical properties and photocatalytic activities were investigated in detail. The photocatalytic activity of the as-obtained photocatalyst were evaluated by degradation of rhodamine B (RhB) and Levofloxacin (LEV) under near IR-UV-vis light irradiation, the CQDs/BiOX composite displayed enhanced photocatalytic activity as compared with individual BiOX materials. The CQDs/BiOX composite had the outstanding light harvesting and electron transfer ability because of the ordered ultrathin nanosheet structure of the BiOX, the formation of metal Bi under photoinduction, and the synergistic effects between CQDs and pure BiOX. Antibacterial activity and effects on Rye seeds growth of the LEV degradation intermediate were also researched. Reactive-species-trapping experiments exhibited that h

Flexible electronics have emerged as an exciting research area in recent years, serving as ideal interfaces bridging biological systems and conventional electronic devices. Flexible electronics can not only collect physiological signals for human health monitoring but also enrich our daily life with multifunctional smart materials and devices. Conductive hydrogels (CHs) have become promising candidates for the fabrication of flexible electronics owing to their biocompatibility, adjustable mechanical flexibility, good conductivity, and multiple stimuli‐responsive properties. To achieve on‐demand mechanical properties such as stretchability, compressibility, and elasticity, the rational design of polymer networks via modulating chemical and physical intermolecular interactions is required. Moreover, the type of conductive components (eg, electron‐conductive materials, ions) and the incorporation method also play an important role in the conductivity of CHs. Electron‐CHs usually possess excellent conductivity, while ion‐CHs are generally transparent and can generate ion gradients within the hydrogel matrices. This mini review focuses on the recent advances in the design of CHs, introducing various design strategies for electron‐CHs and ion‐CHs employed in flexible electronics and highlighting their versatile applications such as biosensors, batteries, supercapacitors, nanogenerators, actuators, touch panels, and displays.

Conductive hydrogels are of great significance for soft electronic devices. However, the intrinsically weak nature, lack of fatigue resistance and self-healing capability, and the absence of stimuli-responsiveness of traditional conductive hydrogels hinder their application as durable, reliable and smart conductors to fulfill the increasing demands of modern electronics. Herein, we have developed a novel hydrogel ionic conductor by integrating nanofiller reinforcement with micelle cross-linking. The hydrogel was facilely prepared via one-pot polymerization of acrylamide and an amino-functionalized monomer in the presence of multiwall carbon nanotubes, aldehyde-modified F127 and LiCl. The dynamic chemical and physical interactions of the cross-linked network provide the hydrogel with a wide spectrum of properties, including excellent stretchability (1200%), skin-mimetic modulus, toughness, exceptional elasticity (recovery from 1000% strain), resistance to damage by sharp materials, self-healing properties (636% stretchability after self-healing) and high conductivity (3.96 S m−1). Besides, the rational design of the hydrogel endows it with multiple sensory capabilities toward temperature, strain and pressure. The hydrogel demonstrated cooling-induced whitening optical behavior. When exploited as a strain and pressure sensor to monitor diverse human motions, the prepared hydrogel sensor showed excellent sensitivity and reliability even for the acquisition of detailed waveform changes of radial artery pulses before and after exercise, suggesting its superior sensitivity compared to previously reported hydrogel sensors. The hydrogel was further integrated with an eye mask to monitor human sleep and showed high reliability for the detection of rapid eye movement (REM) sleep. This work provides new insights into the fabrication of multifunctional, smart and conductive materials, showing great promise for a broad range of applications like wearable sensors, artificial skins, and soft robotics.

Turnover has been a serious concern to social service organizations. A lack of committed social workers is a risk to organizational performance and service quality. Therefore, it is vital to better understand the leaving process of social work practitioners. The study constructed a moderated mediation model to examine the mediating role of job satisfaction between employees’ professionalism and turnover intention and the moderating role of the perceived level of managerialism in the context of social work organizations. A total of 667 participants from Guangzhou, Shenzhen, and Shanghai in China were recruited to complete the survey. Results presented that job satisfaction plays a full mediation role in the relationship between professionalism and turnover intention. In addition, the positive relationship between professionalism and job satisfaction, as well as the negative relationship between professionalism and turnover intention were moderated by managerialism. The findings enrich knowledge about turnover among social workers in the context of China and inspire to foster professionalism among service workers to improve job satisfaction and alleviate turnover intention and actual turnover as well as to apply management techniques and structures properly to strengthen the effect of professionalism on promoting job satisfaction and on preventing turnover intention.

Underwater adhesion is a great challenge for the development of adhesives as the attractive interfacial intermolecular interactions are usually weakened by the surface hydration layer. The coacervation process of sessile organisms like marine mussels and sandcastle worms has inspired substantial research interest in the fabrication of long-lasting underwater adhesives, but they generally suffer from time-consuming curing triggered by surrounding environmental changes and cannot reserve the adhesiveness once damaged. Herein, an instant and repeatable underwater adhesive was developed based on the coacervation of tannic acid (TA) and poly(ethylene glycol)77-b-poly(propylene glycol)29-b-poly(ethylene glycol)77 (PEG-PPG-PEG, F68), which was driven by hydrogen-bonding interaction, and the hydrophobic cores of F68 micelles offered an additional cross-linking to enhance the mechanical properties. The TA-F68 coacervates could be facilely painted on different substrates, exhibiting robust and instant underwater adhesion (with adhesion strength up to 1.1 MPa on porcine skin) and excellent repeatability (at least 1000 cycles), superior to the previously reported coacervates. Due to the biological activities of TA, the underwater adhesive displayed innate anticancer and antibacterial properties against different types of cancer cells and bacteria, showing great potential for diverse biomedical applications, such as injectable drug carriers, tissue glues, and wound dressings.

Although recent years have witnessed intense efforts and innovations in the design of flexible conductive materials for the development of next-generation electronic devices, it remains a great challenge to integrate multifunctionalities such as stretchability, self-healing, adhesiveness, and sensing capability into one conductive system for practical applications. In this work, for the first time, we have prepared a new electrically conductive elastomer composite that combines all these functionalities by triggering in situ polymerization of pyrrole in a supramolecular polymer matrix cross-linked by multiple hydrogen-bonding 2-ureido-4[1 H]-pyrimidinone (UPy) groups. The polypyrrole (PPy) particles were uniformly dispersed and imparted to the composite desirable conductive properties, while the reversible nature of the dynamic multiple hydrogen bonds in the polymer matrix allowed excellent stretchability, fast self-healing ability, and adhesiveness under ambient condition. The elastomer composite with the incorporation of 7.5 wt % PPy displayed a mechanical strength of 0.72 MPa with an elongation over 300%, where the rapid self-healing of the mechanical and electrical properties was achieved within 5 min. The elastic material also exhibited strong adhesiveness to a broad range of inorganic and organic substrates, and it was further fabricated as a strain sensor for the detection of both large and subtle human motions (i.e., finger bending, pulse beating). The novel PPy-doped conductive elastomer has demonstrated great potential as functional sensors for wearable electronics, which provides a facile and promising approach to the development of various flexible electronic materials with multifunctionalities by combining conductive components with supramolecular polymers.

Hydrogen-bonding interaction is one of the most developed approaches for generating supramolecular polymers, and self-assemblies solely based on hydrogen bonds are generally unstable in water. Although considerable efforts have been made to improve the stability of the hydrogen-bonded arrays by other interactions such as hydrophobic interactions, it still remains a challenge to elucidate the effects of surrounding environment on hydrogen bonding at the single-molecular level, which is crucial for developing desired hydrogen-bonded structures. In this work, for the first time, single-molecule force spectroscopy was employed to characterize the binding strength and dynamics of hydrogen-bonded 2-ureido-4[1H]-pyrimidinone (UPy) dimers in water in combination with molecular dynamics (MD) simulations, and the hydrophobic effect was investigated by tethering alkylene spacers of different lengths to the hydrogen binding moieties. The rupture force and unbinding energy of self-complementary UPy–UPy dimers were fou...

3,4-Dihydroxyphenylalanine (Dopa) is a mussel-inspired, unique and versatile adhesive moiety, while zwitterions are well-known for their antifouling and repellent properties. It is still unclear whether zwitterionic surfaces could effectively prevent the adhesion of Dopa units, and a zwitterion–Dopa interaction mechanism may lead to development of a novel wet adhesion strategy. Here we report single-molecule force spectroscopy (SMFS) between Dopa and zwitterionic molecules of opposite dipole orientations, with a much stronger bond dissociation energy for zwitterionic 2-methacryloyloxyethyl phosphorylcholine (MPC, ∼19.4 kBT) than for [2-(methacryloyloxy)ethyl]dimethyl-(3-sulfopropyl)ammonium hydroxide (DMAPS, ∼10.8 kBT). The strong MPC–Dopa interaction could be attributed to the synergy of cation–π interaction and hydrogen bonding, but the DMAPS–Dopa interaction could only be attributed to hydrogen bonding, as further demonstrated by density functional theory (DFT) computation. Based on the orientation-mediated zwitterion–Dopa binding mechanism, we design a polymer containing both MPC and Dopa moieties as a promising underwater adhesive with a measured cohesion of 7.2–14.1 mJ m−2, even stronger than reported cation–π-facilitated underwater adhesives. The elucidated molecular interaction principles shed light on designing novel zwitterion–Dopa-mediated materials with wide applications in various fields such as tissue engineering scaffolds, cell-based screening and underwater adhesives.

Although it has been widely recognized that land fragmentation has increased chemical fertilizer application, little is known about the role of technology adoption in mitigating these adverse effects. To empirically examine the relationship between land fragmentation, technology adoption and chemical fertilizer application, we developed a mediation model. We applied our analysis to a survey data set encompassing 1388 farm-level samples collected in 14 Chinese provinces in 2019. Our study demonstrated that land fragmentation can not only directly increase chemical fertilizer application but also indirectly increase it by hindering the adoption of agricultural mechanization technologies (AMT’s) and soil testing fertilization technologies (STFT’s). Both are recognized as potent drivers of fertilizer use reductions. Moreover, the adoption of information and communications technologies (ICT’s) can help mitigate the negative effects of land fragmentation on technology adoption, thus reducing chemical fertilizer application intensity (CFAI). However, the direct effects of land fragmentation on CAFI was unaffected by ICT’s. Our findings suggest that ICT’s have revolutionized farmer recognition, promotion and adoption of agricultural technologies by increasing awareness and diffusion of agricultural technology information.

Particulate matter (PM), which is the primary contributor to air pollution, has become a pervasive global health threat. When PM enters into a respiratory tract, the first body tissues to be directly exposed are the cells of respiratory tissues and pulmonary surfactant. Pulmonary surfactant is a pivotal component to modulate surface tension of alveoli during respiration. A lot of studies have proved that PM would interact with pulmonary surfactant to affect the alveolar activity, and meanwhile, pulmonary surfactant would be adsorbed to the surface of PM to change the toxic effect of PM. This review focuses on recent studies of the interactions between micro/nanoparticles (synthesized and environmental particles) and pulmonary surfactant (natural surfactant and its models), as well as the health effects that caused by PM through a few significant aspects, such as surface properties of PM, including size, surface charge, hydrophobicity, shape, chemical nature, etc. Moreover, in vitro and in vivo studies showed that PM leads to oxidative stress, inflammatory response, fibrosis, and cancerization in living bodies. By providing a comprehensive picture of PM-surfactant interaction, this review will benefit both researchers for further studies and policy-makers for setting up more appropriate regulations to reduce the adverse effects of PM on public health., Graphic Abstract Unlabelled Image, Highlights • Long-term exposure to particulate matter (PM) reduces life expectancy. • Pulmonary surfactant is the initial tissues contacted with PM . • The interaction behaviors of PM and pulmonary surfactant are systematically reviewed. • Surface properties of PM determine PM-surfactant interactions.

Coacervation plays a critical role in numerous biological activities such as constructing biological tissues and achieving robust wet adhesion of marine sessile organisms, which conventionally occurs when oppositely charged polyelectrolytes are mixed in aqueous solutions driven by electrostatic attraction. Here, a novel type of adhesive coacervate is reported, driven by hydrogen-bonding interactions, readily formed by mixing silicotungstic acid and nonionic polyethylene glycol in water, providing a new approach for developing coacervates from nonionic systems. The as-prepared coacervate is easily paintable underwater, show strong wet adhesion to diverse substrates, and has been successfully applied as a hemostatic agent to treat organ injuries without displaying hemolytic activity, while with inherent antimicrobial properties thus avoiding inflammations and infections due to microorganism accumulation. This work demonstrates that coacervation can occur in salt-free environments via non-electrostatic interactions, providing a new platform for engineering multifunctional coacervate materials as tissue glues, wound dressings and membrane-free cell systems.

Injectable, self-healing, and pH-responsive hydrogels are great intelligent drug delivery systems for controlled and localized therapeutic release. Hydrogels that show pH-sensitive behaviors in the mildly acidic range are ideal to be used for the treatment of regions showing local acidosis like tumors, wounds and infections. In this work, we present a facile preparation of an injectable, self-healing, and supersensitive pH-responsive nanocomposite hydrogel based on Schiff base reactions between aldehyde-functionalized polymers and amine-modified silica nanoparticles. The hydrogel shows fast gelation within 10 s, injectability, and rapid self-healing capability. Moreover, the hydrogel demonstrates excellent stability under neutral physiological conditions, while a sharp gel-sol transition is observed, induced by a faintly acidic environment, which is desirable for controlled drug delivery. The pH-responsiveness of the hydrogel is ultrasensitive, where the mechanical properties, hydrolytic degradation, and drug release behaviors can alter significantly when subjected to a slight pH change of 0.2. Additionally, the hydrogel's mechanical and pH-responsive properties can be readily tuned by its composition. Its excellent biocompatibility is confirmed by cytotoxicity tests toward human dermal fibroblast cells (HDFa). The novel injectable, self-healing, and sensitive pH-responsive hydrogel serves as a promising candidate as a localized drug carrier with controlled delivery capability, triggered by acidosis, holding great promise for cancer therapy, wound healing, and infection treatment.

The rapid development of traditional agriculture in China was achieved at the expense of high energy consumption and investments. However, the global green development trend made it necessary for the country to transform its agricultural energy utilization. Energy efficiency changes are affected by many factors, particularly industrial agglomeration. In recent years, the Chinese government has introduced a series of policies, including setting major producing regions for grains and advantageous regions for characteristic agricultural product. These have caused significant changes to the spatial layout of the agriculture industry. However, there is still a lack of research on the impact of these changes on agricultural energy efficiency (AEE). In this study, panel data of 30 Chinese provinces from 2000 to 2016 were entered into stochastic frontier models to measure the country’s AEE at the provincial level. A series of spatial econometric models were also used to analyze the impact of agricultural industrial agglomeration on China’s AEE. The results indicated that the country’s AEE exhibited obvious spatial gradients and correlations. After controlling the impacts of spatial correlation and other factors in the models, agricultural industrial agglomeration was found to have an overall positive impact on China’s AEE. In the future, policies should be formulated to increase AEE by establishing agricultural functional areas, strengthening the innovation and sharing of green development technologies at the farm level, and promoting the optimization of energy structures in agricultural and rural areas.

A bioinspired zwitterionic polyelectrolyte coating with excellent hydration ability has been regarded as a promising lubricating candidate for modifying artificial joint cartilage surface. In physiological fluids, the ubiquitous proteins play an important role in achieving outstanding boundary lubrication; however, a comprehensive understanding of the hydration lubrication between polyelectrolyte coatings and proteins still remains unclear. In this work, a facile fabrication of ultrasmooth polyelectrolyte coatings was developed via codeposition of synthesized poly(dopamine methacrylamide- co-2-methacryloyloxyethyl phosphorylcholine) (P(DMA- co-MPC)) and dopamine (DA) in a mild condition. Upon optimization of the feeding ratio of P(DMA- co-MPC) and DA, the as-fabricated PDA/P(DMA- co-MPC) coatings exhibit excellent lubricating properties when sliding with each other (friction coefficient μ = 0.036 ± 0.002, ∼2.8 MPa), as well as sliding with a model protein (bovine serum albumin (BSA)) layer (μ = 0.041 ± 0.005, ∼4.8 MPa) in phosphate-buffered saline (PBS, pH 7.4). Intriguingly, the lubrication in both systems shows Amontons-like behaviors: the friction is directly proportional to the applied load but independent of the shear velocity. Moreover, the PDA/P(DMA- co-MPC) coatings could resist the protein fouling (i.e., BSA) in PBS, which is crucial to prevent the surfaces from being contaminated when applied in biological media, thus maintaining their lubricating properties. Our results provide a versatile approach for facilely fabricating polyelectrolyte coatings with superior lubrication properties to both polyelectrolyte coatings and protein surfaces, with useful implications into the development of novel lubricating coatings for bioengineering applications (e.g., artificial joints).

Chronic obstructive pulmonary disease (COPD) is a chronic and progressive lung disease characterized by a mixture of small airway disease and lung tissue parenchymal destruction. Abnormal inflammatory responses to cigarette smoking and other noxious particles are generally thought to be responsible for causing of COPD. Since airway inflammation is a key factor in COPD progress, it is crucial to unravel its underlying molecular mechanisms. Unbiased analysis of genome-wide gene expression profiles in lung small airway epithelial cells provides a powerful tool to investigate this. Gene expression data of GSE611906, GSE20257, GSE8545 were downloaded from GEO database. All 288 lung small airway samples in these cohorts, including donors with (n = 61) and without (n = 227) COPD, were chosen for differential gene expression analysis. The gene ontology (GO) function, Kyoto Encyclopedia of Genes and Genomes pathway (KEGG) enrichment analyses, gene co-expression network analysis (WGCNA) and protein–protein interaction (PPI) network analysis were performed. Subsequently, the analyses of IL1B expression level, the Pearson correlation between IL1B and several COPD biomarkers were performed using other cohorts to validate our main findings. With a change ≥ twofold and P value

Aims Evidence shows that aberrant expression of long non-coding RNA (lncRNA) is closely associated with tumor development and progression. However, the role of lncRNA in environmental carcinogen induced gastric tumorigenesis remains largely unknown. This study aimed at investigating the function role of lncRNA in N -methyl- N ′-nitro- N -nitrosoguanidine (MNNG) induce malignantly transformed human gastric epithelial cells. Main methods In this study, high-throughput sequencing and qRT-PCR assay revealed marked downregulation of lncRNA LOC101927497 in the malignant transformed gastric epithelial cells induced by MNNG (GES-1-T cells), gain-of-function and loss-of-function assays showed that LOC101927497 can suppress the proliferation and migration of GES-1-T cells in vitro. RNA antisense purification experiment showed that LOC101927497 interacted with miR-574-5p in GES-1-T cells the most obvious. Further studies suggested that LOC101927497 may function as a tumor suppressor by interacting with miR-574-5p. Key findings LncRNA LOC101927497 functions as a suppressor by interacting with miR-574-5p, thus inhibiting the malignant phenotype of GES-1-T cells. Significance To the best of our knowledge, this is the first study to demonstrate the role of lncRNA in MNNG-induced gastric tumorigenesis, and it will provide new insights into the role of lncRNA in environmental carcinogen-induced gastric cancer.

Increasing evidence suggests that therapy-induced senescence (TIS), a novel therapeutic approach in which low doses of therapeutic drugs or radiation are used to induce senescence, suppresses tumor development. Our previous in vitro studies have demonstrated that a low dose of metformin promoted hepatoma cell senescence instead of apoptosis via activation of AMP-activated protein kinase (AMPK) and inactivation of Sirtuin 1 (SIRT1) deacetylase activity. However, the intricate relationship between AMPK and SIRT1, and how they cooperate to induce senescence remains elusive. We showed here that persistent exposure to a low concentration of metformin led to AMPK activation in a mouse xenograft model of human hepatocellular carcinoma (HCC), resulting in senescence. Intriguingly, AMPK counter-regulated SIRT1 via direct phosphorylation in metformin-mediated senescence in hepatoma cells. Taken together, these findings suggest that a low dose of metformin could potentially be used as a TIS-inducing therapeutic drug for HCC, and that this occurs by inducing senescence of HCC cells via the AMPK-SIRT1 pathway.