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Liver kinase B1 (Lkb1), encoded by serine/threonine kinase (Stk11), is a serine/threonine kinase and tumor suppressor that is strongly implicated in Peutz–Jeghers syndrome (PJS). Numerous studies have shown that mesenchymal‐specific Lkb1 is sufficient for the development of PJS‐like polyps in mice. However, the cellular origin and components of these Lkb1‐associated polyps and underlying mechanisms remain elusive. In this study, we generated tamoxifen‐inducible Lkb1flox/flox;Myh11‐Cre/ERT2 and Lkb1flox/flox;PDGFRα‐Cre/ERT2 mice, performed single‐cell RNA sequencing (scRNA‐seq) and imaging‐based lineage tracing, and aimed to investigate the cellular complexity of gastrointestinal polyps associated with PJS. We found that Lkb1flox/+;Myh11‐Cre/ERT2 mice developed gastrointestinal polyps starting at 9 months after tamoxifen treatment. scRNA‐seq revealed aberrant stem cell‐like characteristics of epithelial cells from polyp tissues of Lkb1flox/+;Myh11‐Cre/ERT2 mice. The Lkb1‐associated polyps were further characterized by a branching smooth muscle core, abundant extracellular matrix deposition, and high immune cell infiltration. In addition, the Spp1–Cd44 or Spp1–Itga8/Itgb1 axes were identified as important interactions among epithelial, mesenchymal, and immune compartments in Lkb1‐associated polyps. These characteristics of gastrointestinal polyps were also demonstrated in another mouse model, tamoxifen‐inducible Lkb1flox/flox;PDGFRα‐Cre/ERT2 mice, which developed obvious gastrointestinal polyps as early as 2–3 months after tamoxifen treatment. Our findings further confirm the critical role of mesenchymal Lkb1/Stk11 in gastrointestinal polyposis and provide novel insight into the cellular complexity of Lkb1‐associated polyp biology. © 2024 The Pathological Society of Great Britain and Ireland. [ABSTRACT FROM AUTHOR]

Background: In China, over 50% of lung cancer cases occur in nonsmokers. Thus, identifying high‐risk individuals for targeted lung cancer screening is crucial. Beyond age and smoking, determining other risk factors for lung cancer in the Asian population has become a focal point of research. Using 30,000 participants in the prospectively enrolled cohort at China's National Cancer Center (NCC) over the past 14 years, we categorized participants by risk, with an emphasis on nonsmoking females. Materials and Method s : Between November 2005 and December 2019, 31,431 individuals voluntarily underwent low‐dose computed tomography (LDCT) scans for lung cancer screening at the NCC. We recorded details like smoking history, exposure to hazards, and family history of malignant tumors. Using the 2019 NCCN criteria, participants were categorized into high‐, moderate‐, and low‐risk groups. Additionally, we separated non‐high‐risk groups into female never smokers (aged over 40) exposed to second‐hand smoke (SHS) and others. Any positive results from initial scans were monitored per the I‐ELCAP protocol (2006), and suspected malignancies were addressed through collaborative decisions between patients and physicians. We analyzed and compared the detection rates of positive results, confirmed lung cancers, and cancer stages across risk, age, and gender groups. Results: Out of 31,431 participants (55.9% male, 44.1% female), 3695 (11.8%) showed positive baseline LDCT scans with 197 (0.6%; 106 females, 91 males) confirmed as lung cancer cases pathologically. Malignancy rate by age was 0.1% among those aged under 40 years, 0.4% among those aged 40–49 years, 0.8% among those aged 50–59 years, and 1.2% among those aged 60 years and older. From the 25,763 participants (56.9% male, 43.1% female) who completed questionnaires, 1877 (7.3%) were categorized as high risk, 6500 (25.2%) as moderate risk, and 17,386 (67.5%) as low risk. Of the 23,886 in the non‐high‐risk category, 8041 (33.7%) were females over 40 years old exposed to SHS. The high‐risk group showed the highest lung cancer detection rate at 1.4%. However, females exposed to SHS had a notably higher detection rate than the rest of the non‐high‐risk group (1.1% vs. 0.5%; p < 0.0001). In this cohort, 84.8% of the detected lung cancers were at an early stage. Conclusions: In our study, using LDCT for lung cancer screening proved significant for high‐risk individuals. For non‐high‐risk populations, LDCT screening could be considered for nonsmoking women with exposure to SHS. [ABSTRACT FROM AUTHOR]

Lung cancer is a leading cause of cancer‐related deaths worldwide. Recent studies have identified pyroptosis, a type of programmed cell death, as a critical process in the development and progression of lung cancer. In this study, we investigated the effect of EEBR, a new compound synthesized by our team, on pyroptosis in non‐small cell lung cancer cells (NSCLC) and the underlying molecular mechanisms. Our results demonstrated that EEBR significantly reduced the proliferation and metastasis of NSCLC cells in vitro. Moreover, EEBR‐induced pyroptosis in NSCLC cells, as evidenced by cell membrane rupture, the release of cytokines such as interleukin‐18 and interleukin‐1 beta and the promotion of Gasdermin D cleavage in a Caspase‐1‐dependent manner. Furthermore, EEBR promoted the nuclear translocation of NF‐κB and upregulated the protein level of NLRP3. Subsequent studies revealed that EEBR‐induced pyroptosis was suppressed by the inhibition of NF‐κB. Finally, EEBR effectively suppressed the growth of lung cancer xenograft tumours by promoting NSCLC pyroptosis in animal models. Taken together, our findings suggest that EEBR induces Caspase‐1‐dependent pyroptosis through the NF‐κB/NLRP3 signalling cascade in NSCLC, highlighting its potential as a candidate drug for NSCLC treatment. [ABSTRACT FROM AUTHOR]

Force‐responsive molecules that produce fluorescent moieties under stress provide a means for stress‐sensing and material damage assessment. In this work, we report a mechanophore based on Diels‐Alder adduct TAD‐An of 4,4′‐(4,4′‐diphenylmethylene)‐bis‐(1,2,4‐triazoline‐3,5‐dione) and initiator‐substituted anthracene that can undergo retro‐Diels‐Alder (rDA) reaction by pulsed ultrasonication and compressive activation in bulk materials. The influence of having C−N versus C−C bonds at the sites of bond scission is elucidated by comparing the relative mechanical strength of TAD‐An to another Diels‐Alder adduct MAL‐An obtained from maleimide and anthracene. The susceptibility to undergo rDa reaction correlates well with bond energy, such that C−N bond containing TAD‐An degrades faster C−C bond containing MAL‐An because C−N bond is weaker than C−C bond. Specifically, the results from polymer degradation kinetics under pulsed ultrasonication shows that polymer containing TAD‐An has a rate constant of 1.59×10−5 min−1, while MAL‐An (C−C bond) has a rate constant of 1.40×10−5 min−1. Incorporation of TAD‐An in a crosslinked polymer network demonstrates the feasibility to utilize TAD‐An as an alternative force‐responsive probe to visualize mechanical damage where fluorescence can be "turned‐on" due to force‐accelerated retro‐Diels‐Alder reaction. [ABSTRACT FROM AUTHOR]

Insufficient immune cell infiltration into the tumor microenvironment (TME) greatly compromises the clinical application of immune‐checkpoint inhibitors (ICIs)‐based immunotherapy. Recent findings have shown that activation of the cyclic GMP‐AMP synthase‐stimulator of interferon genes (cGAS‐STING) pathway can enhance natural immunity and increase lymphocyte infiltration into the TME, which presents a promising strategy for cancer immunotherapy. In this study, we constructed hydroxyapatite nanoparticles co‐loaded with curcumin and L‐oxaliplatin (Cur/L‐OHP@HAP NPs). We analyzed the particle‐size distribution, zeta potential, spectral characteristics (Fourier‐transform infrared spectroscopy, X‐ray photoelectron spectroscopy, ultraviolet–visible spectroscopy), and drug‐release properties of the Cur/L‐OHP@HAP NPs. The cellular uptake of the Cur/L‐OHP@HAP NPs detected by flow cytometry and confocal laser‐scanning microscopy. We comprehensively evaluated the anti‐tumor properties and immune‐activating effects of the NPs, both in vitro and in vivo. Physicochemical characterizations demonstrated that the Cur/L‐OHP@HAP NPs were successfully synthesized and were capable of pH‐dependent drug release. Notably, the Cur/L‐OHP@HAP NPs efficiently entered cancer cells, after which the released L‐OHP induced nuclear DNA (nDNA) damage to some extent. HAP promoted the release of intracellular Ca2+ stores in cancer cells, and curcumin inhibited Ca2+ efflux, resulting in intracellular Ca2+ overload and the release of mitochondrial DNA (mtDNA). Damage to both nDNA and mtDNA greatly stimulated the cGAS‐STING pathway, thereby activating natural immunity, accompanied by immune cell recruitment to the TME. In summary, the Cur/L‐OHP@HAP NPs show good prospects for improving cancer immunotherapy. [ABSTRACT FROM AUTHOR]

In this paper, we study the low Mach and Froude number limit of global strong solutions to the fluid‐vacuum free boundary problem of the planar magnetohydrodynamic (MHD) equations with degenerate viscosity coefficients and well‐prepared initial data. Only the initial energy at the basic level is required to be small. The main difficulties are the degeneracy of the system yielded by vanishing of the density close to the free boundary, the singular terms due to the large coefficients inversely proportional to the Mach number and the Froude number, and the strong coupling of the magnetic field and the velocity. The uniform estimates of solutions with respect to the Mach number and the Froude number are established, which is the first result on the MHD equations with vacuum free boundary. At the same time, we obtain the convergence rates for the strong solutions global in time with well‐prepared initial data as the Mach number and the Froude number vanish. [ABSTRACT FROM AUTHOR]

Introduction: Patients presenting with brain metastases (BMs) from lung squamous cell carcinoma (LUSC) often encounter an extremely poor prognosis. A well‐developed prognostic model would assist physicians in patient counseling and therapeutic decision‐making. Methods: Patients with LUSC who were diagnosed with BMs between 2000 and 2018 were reviewed in the Surveillance, Epidemiology, and End Results (SEER) database. Using the multivariate Cox regression approach, significant prognostic factors were identified and integrated. Bootstrap resampling was used to internally validate the model. An evaluation of the performance of the model was conducted by analyzing the area under the curve (AUC) and calibration curve. Results: A total of 1812 eligible patients' clinical data was retrieved from the database. Patients' overall survival (OS) was significantly prognosticated by five clinical parameters. The nomogram achieved satisfactory discrimination capacity, with 3‐, 6‐, and 9‐month AUC values of 0.803, 0.779, and 0.760 in the training cohort and 0.796, 0.769, and 0.743 in the validation cohort. As measured by survival rate probabilities, the calibration curve agreed well with actual observations. There was also a substantial difference in survival curves between the different prognostic groups stratified by prognostic scores. For ease of access, the model was deployed on a web‐based server. Conclusions: In this study, a nomogram and a web‐based predictor were developed to assist physicians with personalized clinical decisions and treatment of patients who presented with BMs from LUSC. [ABSTRACT FROM AUTHOR]

Background and Aims: Liver diseases present a wide range of fibrosis, from fatty liver with no inflammation to steatohepatitis with varying degrees of fibrosis, to established cirrhosis leading to HCC. In a multivariate analysis, serum levels of spermidine were chosen as the top metabolite from 237 metabolites and its levels were drastically reduced along with progression to advanced steatohepatitis. Our previous studies that showed spermidine supplementation helps mice prevent liver fibrosis through MAP1S have prompted us to explore the possibility that spermidine can alleviate or cure already developed liver fibrosis. Methods: We collected tissue samples from patients with liver fibrosis to measure the levels of MAP1S. We treated wild‐type and MAP1S knockout mice with CCl4‐induced liver fibrosis with spermidine and isolated HSCs in culture to test the effects of spermidine on HSC activation and liver fibrosis. Results: Patients with increasing degrees of liver fibrosis had reduced levels of MAP1S. Supplementing spermidine in mice that had already developed liver fibrosis after 1 month of CCl4 induction for an additional 3 months resulted in significant reductions in levels of ECM proteins and a remarkable improvement in liver fibrosis through MAP1S. Spermidine also suppressed HSC activation by reducing ECM proteins at both the mRNA and protein levels, and increasing the number of lipid droplets in stellate cells. Conclusions: Spermidine supplementation is a potentially clinically meaningful approach to treating and curing liver fibrosis, preventing cirrhosis and HCC in patients. [ABSTRACT FROM AUTHOR]

Aim: Psilocin is an active metabolite form of psilocybin and exerts psychoactive effects. Recent studies suggest that psilocin may have regulatory effects on abuse drugs, but the mechanisms remain unclear. In this study, we want to explore the effects of psilocin on methamphetamine (METH)‐induced alterations of behavior in mice and its molecular mechanisms. Methods: Acute METH administration model and conditioned place preference (CPP) model were used to investigate the effects of psilocin on METH‐induced alterations of behavior. Western blot was used to detect the expression of proteins. Results: In the acute 2 mg/kg METH administration model, 1 mg/kg psilocin counteracted METH‐induced elevation of activity. In the 1 mg/kg METH‐induced CPP model, 1 mg/kg psilocin inhibited CPP formation during the acquisition phase. However, psilocin did not impact METH extinction and relapse. Molecular results showed that the regulatory effect of psilocin on METH was underscored by altered expression of dopamine 2 receptor (D2R) and phosphorylated extra‐cellular signal‐regulated kinase (p‐ERK) in the prefrontal cortex (PFC), nucleus accumbens (NAc), and ventral tegmental area (VTA). Trifluoperazine (TFP)‐2HCl is a D2R inhibitor, and SCH772984 is a selective extra‐cellular signal‐regulated kinase (ERK) inhibitor that effectively inhibits ERK1/2 phosphorylation. The results indicated that 2 mg/kg TFP‐2HCl and 10 mg/kg SCH772984 blocked METH‐induced hyperactivity and acquisition of METH‐induced CPP. Conclusion: Psilocin has regulatory effects on METH‐induced alterations of behavior in mice via D2R‐mediated signal regulation of ERK phosphorylation. [ABSTRACT FROM AUTHOR]

Comprehensive Summary: The biochemical property and functional identification of three recombinant glycosyltransferases, including β‐1,4‐rhamnosyltransferase (Cps8R), β‐1,4‐galactosyltransferase (Cps8J) and α‐2,3‐sialyltransferase (Cps8K) involved in the biosynthesis of the tetrasaccharide repeating unit of serotype VIII capsular polysaccharide (CPS) of Group B Streptococci (GBS), were systematically investigated. Subsequently, these recombinant enzymes were employed for one‐pot three‐enzyme efficient synthesis of the tetrasaccharide repeating unit of GBS serotype VIII CPS using the chemically synthesized Glcα‐PP‐(CH2)11‐OPh as the starting substrate in a satisfying yield of 87%. [ABSTRACT FROM AUTHOR]

The biomedical application of corannulene π‐bowls is historically limited by low solubility and bioavailability despite the potential in their unique electronic properties for new functional materials. Herein, the unexpected role and molecular mechanism of Corranulene π‐bowls are uncovered in biomedical applications as an effective anticancer agent for Warburg effect mediated selective tumor targeting. The corannulene triazolyl monosaccharides Cor‐sugars exhibit highly potent cytotoxicity against human cancer cells and effectively inhibit xenograft growth of hyperglycolytic tumors. Particularly, the galactose‐conjugated Cor‐gal exhibits superior in vivo anticancer efficacy in A549 tumor models with outstanding safety profile compared to doxorubicin. Moreover, the combined treatment of Cor‐gal with immune checkpoint inhibitor results in an effective synergy in treating H460 human lung carcinoma. An uptake mechanism study reveals that Cor‐sugars exploit tumor‐specific glucose transporter glucose transporter 1 (GLUT1) for targeted cell delivery and intra‐tumoral accumulation through the cancer‐specific Warburg effect. Their significant anticancer activity is attributed to multiphasic DNA‐binding and cell cycle alteration effects. This study uncovers new molecular properties of corannulene buckybowl and enabling their potential new applications in biomedical engineering. [ABSTRACT FROM AUTHOR]

Aims: Patients with heart failure (HF) have a poor prognosis and are categorized by ejection fraction. We performed a meta‐analysis to compare baseline characteristics and long‐term outcomes of patients with heart failure with reduced (HFrEF), mid‐range (HFmrEF), and preserved ejection fraction (HFpEF). Methods and Results: A total of 27 prospective studies were included. Patients with HFpEF were older and had a higher proportion of females, hypertension, diabetes, and insufficient neuroendocrine antagonist treatments, while patients with HFrEF and HFmrEF had a higher prevalence of coronary heart disease and chronic kidney disease. After more than 1‐year of follow‐up, all‐cause mortality was significantly lower in patients with HFmrEF 9388/25 042 (37.49%) than those with HFrEF 39 333/90 023 (43.69%) and HFpEF 24 828/52 492 (47.30%) (p <.001). Cardiovascular mortality was lowest in patients with HFpEF 1130/9904 (11.41%), highest in patients with HFrEF 3419/16 277 (21.07%) mainly coming from HF death and sudden cardiac death, and middle in patients with HFmrEF 699/5171 (13.52%) and the non‐cardiovascular mortality was on the contrary. Subgroup analysis showed that in high‐risk patients with atrial fibrillation, the all‐cause mortality of HFpEF was significantly higher than both HFrEF and HFmrEF (p <.001). HF hospitalization was lowest in patients with HFmrEF 1822/5285 (34.47%), highest in patients with HFrEF 12 607/28 590 (44.10%) and middle in patients with HFpEF 8686/22 763 (38.16%) and the composite of all‐cause mortality and HF hospitalization was also observed similar results. Conclusions: In summary, patients with HFmrEF had the lowest incidence of all‐cause mortality and HF hospitalization, while the highest all‐cause mortality and HF hospitalization rates were HFpEF and HFrEF patients, respectively. [ABSTRACT FROM AUTHOR]

The enzymatic activity and function of a new α‐1,3‐glucosyltransferase, Cps18CU, derived from Streptococcus pneumoniae serotype 18C was identified for the first time using the enzymatically synthetic disaccharide Rhaβ1,4‐Glcα‐PP‐O(CH2)11‐OPh as the acceptor substrate. Further investigation on substrate specificity revealed that Cps18CU exhibited broad toleration toward various NDP‐Glc donors and also accepted such disaccharide acceptor containing Rhaβ1,4‐Glc moiety in structure. Finally, Cps18CU was employed into a one‐pot two‐enzyme reaction system, furnishing trisaccharide Glcα1,3‐Rhaβ1,4‐Glcα‐PP‐O(CH2)11‐OPh in an 81 % yield. [ABSTRACT FROM AUTHOR]

Patients with subcutaneous panniculitis-like T-cell lymphoma (SPTCL) are prone to the development of hemophagocytic lymphohistiocytosis (HLH). It is not known whether small infections in SPTCL patients can trigger the development of HLH. The clinical data were collected from 21 SPTCL patients admitted to our hospital from January 2006 to October 2019. Among 21 cases of SPTCL, six cases had HLH as the first manifestation (SPTCL/HLH), seven cases had intrathoracic infection (ITI), five cases were SPTCL/HLH, 13 cases had no ITI or HLH (SPTCL/no HLH). Two patients with SPTCL/noHLH healed spontaneously. We found that 28.6% of the SPTCL patients had HLH as the first presentation. ITI may cooperate with SPTCL to trigger HLH and a small number of SPTCL/noHLH can fully recover without treatment., (© 2021 Wiley Periodicals LLC.)