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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]

The Brassicaceae is an economically and scientifically important family distributed globally, including oilseed rape and the model plant, Arabidopsis thaliana. Although growing molecular data have been used in phylogenetic studies, the relationships among major clades and tribes of Brassicaceae are still controversial. Here, we investigated the core Brassicaceae phylogenetics using 222 plastomes and 235 nrDNA cistrons, including 106 plastomes and 112 nrDNA cistrons assembled from newly sequenced genome skimming data of 112 taxa. The sampling covered 73 genera from 61.5% tribes and four unassigned genera and species. Three well supported lineages LI, LII, and LIII were revealed in our plastomic analyses, with LI sister to LII + LIII. In addition, the monophyly of the newly delimitated LII was strongly supported by three different partition strategies, concatenated methods under Bayesian and Maximum Likelihood analyses. LII comprised 13 tribes, including four tribes previously unassigned to any lineage, that is Biscutelleae as the earliest diverging clade and Cochlearieae as the sister to Megacarpaeeae + Anastaticeae. Within LII, the intertribal relationships were also well resolved, except that a conflicting position of Orychophragmus was detected among different datasets. In LIII, Shehbazia was resolved as a member of Chorisproreae, but Chorisproreae, Dontostemoneae, and Euclidieae were all resolved as paraphyletic, which was also confirmed by nrDNA analyses. Moreover, the loss of the rps16 gene was detected as likely to be a synapomorphy of the tribes Arabideae and Alysseae. Overall, using genome skimming data, we resolved robust phylogenetic relationships of core Brassicaceae and shed new light on the complex evolutionary history of this family. [ABSTRACT FROM AUTHOR]

Periodontitis is a chronic inflammatory disease that results in the destruction of periodontal soft tissue and the resorption of alveolar bone. Evidence indicates that in diabetic patients, hyperglycemia suppresses periodontal ligament stem cell (PDLSC) functions and leads to difficulties in periodontal repair. The present study aimed to explore the mechanisms by which high‐glucose concentrations aggravate cell viability reduction in human CD146‐positive PDLCs (CD146+PDLCs) under tumor necrosis factor‐alpha (TNF‐alpha) induction. CD146+PDLCs were isolated from periodontal ligament tissues and treated in the absence or presence of 10 ng/ml of TNF‐alpha and 30 mM glucose. Cell viability was detected using Cell Counting Kit‐8 assays and Luminescent Cell Viability Assays. Western blotting and real‐time polymerase chain reaction were performed to determine tumor necrosis factor‐alpha receptor‐1 (TNFR‐1) protein and messenger RNA expression. Bisulfite and MassArray methylation analyses were used to analyze the methylation status of the TNFR‐1 gene. Our results indicated that cell viability was reduced after treatment with a combination of both high‐glucose concentration and TNF‐alpha. Treatment with 30 mM glucose suppressed DNA methyltransferase (DNMT) activities and DNMT1 protein expression, and this was accompanied by the upregulation of TNFR‐1. Additionally, we found that the CpG island located within the TNFR‐1 gene was hypomethylated under 30 mM glucose conditions. S‐adenosylmethionine, an established methyl donor, reversed TNFR‐1 upregulation and restored cell viability against high‐glucose concentration and TNF‐alpha. In conclusion, the present findings suggest that high‐glucose‐induced CpG island hypomethylation within the TNFR‐1 gene plays an essential role in TNFR‐1 upregulation, and this further enhances the cell viability reduction of CD146+PDLCs caused by TNF‐alpha. [ABSTRACT FROM AUTHOR]

The aim of this study was to explore the effects of platelet‐rich plasma on gingipain‐caused changes in cell morphology and apoptosis of osteoblasts. Mouse osteoblasts MC3T3‐E1 cells were treated with gingipain extracts from Porphyromonas gingivalis in the presence or absence of platelet‐rich plasma. Apoptosis was detected with terminal deoxynucleotidyl transferase‐mediated dUTP nick‐end labeling staining. F‐actin was determined by phalloidin‐fluorescent staining and observed under confocal microscopy. Western blot analysis was used to detect integrin β1, F‐actin, and G‐actin protein expressions. A knocking down approach was used to determine the role of integrin β1. The platelet‐rich plasma protected osteoblasts from gingipain‐induced apoptosis in a dose‐dependent manner, accompanied by upregulation of integrin β1. Platelet‐rich plasma reversed the loss of F‐actin integrity and decrease of F‐actin/G‐actin ratio in osteoblasts in the presence of gingipains. By contrast, the effects of platelet‐rich plasma were abrogated by knockdown of integrin β1. The platelet‐rich plasma failed to reduce cell apoptosis and reorganize the cytoskeleton after knockdown of integrin β1. In conclusion, platelet‐rich plasma inhibits gingipain‐induced osteoblast apoptosis and actin cytoskeleton disruption by upregulating integrin β1 expression. [ABSTRACT FROM AUTHOR]

Aims: To investigate the association of baseline serum uric acid (UA) with new‐onset diabetes, and to explore the possible effect modifiers in Chinese adults with hypertension. Materials and methods: A total of 14 943 hypertensive patients with available UA measurements and without diabetes at baseline were included from the China Stroke Primary Prevention Trial (CSPPT). Participants were randomly assigned to a double‐blind daily treatment with 10 mg enalapril and 0.8 mg folic acid or 10 mg enalapril alone. The primary outcome was new‐onset diabetes, defined as physician‐diagnosed diabetes or use of glucose‐lowering drugs during follow‐up, or fasting glucose ≥7.0 mmol/L at the exit visit. Results: Over a median follow‐up of 4.5 years, 1623 participants (10.9%) developed diabetes. Overall, there was a positive association between baseline UA and new‐onset diabetes in women (per SD increment; adjusted odds ratio [OR] 1.14, 95% confidence interval [CI] 1.07, 1.23), but not in men (adjusted OR 1.01, 95% CI 0.92, 1.10). Moreover, a stronger positive association between baseline UA and new‐onset diabetes was found among women with lower time‐averaged on‐treatment systolic blood pressure during the treatment period (<140 vs. ≥140 mmHg; P‐interaction = 0.024), higher baseline body mass index (<24 vs. ≥24 kg/m2; P‐interaction = 0.012), or higher baseline waist circumference (<80 vs. ≥80 cm; P‐interaction = 0.032). Conclusions: Our study suggested that higher baseline UA was significantly associated with increased risk of new‐onset diabetes in hypertensive Chinese women, but not in men. Further prospective studies are required to validate the differential association by sex. [ABSTRACT FROM AUTHOR]

An in‐depth theoretical study has been performed to investigate the mechanism of alkene dehydrogenative silylation catalyzed by the bis(imino)pyridine cobalt methyl complex (MesPDI)Co(CH3) on the singlet, triplet and open‐shell singlet potential energy surfaces as well as the corresponding minimum energy crossing points. The formation of active catalyst [(MesPDI)Co(CH3)+HSiR3→(MesPDI)Co−[Si]+CH4] follows an open‐shell singlet potential energy surface, while the active catalyst has a triplet ground state. For 1‐butene as substrate, the formation of E/Z‐allylsilanes follows the singlet surface; and the E‐allylsilane is more favored than the Z‐allylsilane kinetically, and the expected ratio agrees with the experiment. For bulky 4,4‐dimethyl‐1‐pentene as substrate, the selectivity of allylsilane and vinylsilane is thermodynamically determined and this is supported by the need of low silane/olefin ratio (1/4) in experiment. [ABSTRACT FROM AUTHOR]

Background: Hyperglycemic micro-environment induced by diabetes could regulate the response of periodontal tissues to pathogenic microorganisms in which disruption of autophagy lysosomal pathway (ALP) may participate. This study aimed to explore the mechanisms underlying how high glucose (HG) regulates ALP in gingival epithelial cells (GECs).Methods: Human gingival tissues in healthy group (C), periodontitis group (P), diabetes group (DM), and diabetes + periodontitis group (DP) were collected and were applied to observe the fusion of autophagy and lysosome. Diabetic mouse model with periodontitis was established and RNA-seq was applied to investigate the expression of ALP-associated genes in gingival epithelium. To explore the key role of ATPase transmembrane v0 domain, subunit c (ATP6V0C) in the disruption of ALP by HG, human gingival epithelial cells (HGECs) were cultured in 5.5 mM/25 mM glucose medium for 48 hours and followed by Porphyromonas gingivalis stimulation for 0, 6, and 12 hours. HBLV-h-ATP6V0C was transfected in HGECs that were stimulated by 25 mM HG condition.Results: Immunofluorescence double staining exhibited the disruption of ALP in human gingival epithelium in diabetes groups and HGECs under 25 mM glucose condition, accompanied with significantly downregulated lysosomal acidity. RNA-seq of mouse gingival epithelium screened out Atp6v0c. Compared with HGECs in normal culture medium, ATP6V0C expression and LC3-II/I expression ratio were significantly downregulated, with an upregulated expression of P62, IL-1β in HGECs under HG condition. Over-expression of ATP6V0C rescued HG-induced disruption of ALP in HBLV-h-ATP6V0C transfected HGECs, with significantly upregulation of LC3-II/I and downregulation of P62, IL-1β.Conclusion: ATP6V0C mediates HG-induced ALP disruption in HGECs, eventually exacerbates periodontal inflammation. [ABSTRACT FROM AUTHOR]

Previous studies have shown that arctigenin is a promising chemopreventive or therapeutic agent against various cancers. However, less is known about anticancer activity of 3'-desmethylarctigenin (3'-DMAG), which is a biotransformed product from arctigenin or arctin. In this study, we compared the anticancer activity of 3'-DMAG with its parent compound arctigenin and demonstrated that 3'-DMAG exerted a more potent inhibitory effect on HepG2 cells than arctigenin. Mechanistically, reactive oxygen species generation played an apical role in 3'-DMAG-induced G2/M cell cycle arrest and apoptosis in HepG2 cells. Furthermore, the Chk2-Cdc25c-Cdc2-cyclin B1 cascade was found to contribute to the cell cycle arrest, whereas the activation of mitochondrial pathway was involved in the cell apoptosis by 3'-DMAG. Additionally, a mouse xenograft hepatocellular carcinoma model was used to evaluate the antitumor effect of 3'-DMAG in vivo, and the results indicated that 3'-DMAG treatment significantly inhibited tumor growth without apparent toxicity. Taken together, 3'-DMAG is highly effective against liver cancer both in vitro and in vivo. The findings of the present study suggest that this compound deserves to be further investigated for its potential anticancer activity. [ABSTRACT FROM AUTHOR]

Objectives: Circular RNAs (circRNAs) are non‐coding RNAs, some of which are thought to be involved in gastric cancer development. Here, we examined the functions of circRNA hsa_circ_006100 in gastric cancer cells and an animal model of gastric cancer. Materials and Methods: The expression of hsa_circ_006100, miR‐195 and various functional genes was determined by quantitative RT‐PCR. Cell viability, clone formation, apoptosis and cell migration/invasion abilities were analysed by the CCK‐8 assay, crystal violet staining, Hoechst staining and Transwell assay, respectively. A tumour model was established by subcutaneously injecting tumour cells into nude mice. Levels of protein expression were analysed by Western blotting and immunohistochemistry. Results: A bioinformatics analysis showed that miR‐195 was negatively co‐expressed with hsa_circ_006100. Patients with a high hsa_circ_006100 level or low miR‐195 level had tumours with a high TNM stage, poor cellular differentiation and lymph node metastasis. miR‐195 was targeted and inhibited by hsa_circ_006100. Overexpression of hsa_circ_006100 enhanced cellular viability and proliferation, while miR‐195 suppressed hsa_circ_006100‐enhanced cell growth and induced apoptosis in MGC‐803 and AGS cells. Forced hsa_circ_006100 expression promoted the migration and invasion of MGC‐803 and AGS cells, while those activities were inhibited by miR‐195. Mechanistically, GPRC5A was predicted as a target of miR‐195 and was upregulated in gastric cancer. A miR‐195 inhibitor restored cell viability, proliferation, migration and invasion, and repressed apoptosis via GPRC5A. In vivo studies showed that knockdown of hsa_circ_006100 delayed tumour growth, reduced PCNA expression and upregulated miR‐195 and BCL‐2 expression which was restored by miR‐195 inhibition due to GPRC5A/EGFR signalling, and changed the EMT phenotype in vivo. Conclusions: Hsa_circ_006100 functions as an oncogene in gastric cancer and exerts its effects via miR‐195/GPRC5A signalling. [ABSTRACT FROM AUTHOR]

Introduction: Although mutations in the human beta‐globin gene cluster are essentially point mutations, several large deletions have been described in recent years. Methods: We have identified a novel 223 kb deletion in a Chinese patient by multiplex ligation‐dependent probe amplification and characterized it by next‐generation sequencing, Gap‐PCR, and DNA sequence analysis. Results: The deletion extends from the 3′UTR of the δ globin gene (HBD) to 215 kb downstream of the HBB. Compound heterozygous with the typical β‐thalassemia—CD41‐42(‐CTTT) mutation, the proband presented with microcytosis and hypochromic red cells, and required regulate transfusion. The patient was clinically diagnosed with thalassemia major. Conclusion: Our study widens the mutation spectrum of β‐thalassemia. In addition, this case may spark future studies of the regulatory regions of the beta‐globin gene cluster. [ABSTRACT FROM AUTHOR]

Few burn dressings can self‐regulate the optimal humidity levels that are required for wound healing, while also providing good anti‐adhesive properties to prevent damage that can occur when wound dressings are changed. Consequently, a water‐soluble carboxymethylcellulose sodium/sodium alginate/chitosan (CMC‐Na/SA/CS) composite hydrogel has been developed as a potential burn wound dressing, with orthogonal testing revealing an optimal ratio of CMC‐Na, SA, and CS as 2, 3, and 1 wt % for hydrogel preparation, respectively. The resultant hydrogel has been formulated into composite wound dressings that were then used for the treatment of deep second degree burn wounds in Sprague–Dawley (SD) rats. Analysis of the physical properties of this dressing revealed that it exhibits good water vapor permeability properties that promote the healing of deep second‐degree burn wounds. The pro‐healing mechanism of the dressing has been investigated Vascular endothelial growth factor (VEGF) expression was upregulated and basic fibroblast growth factor (bFGF) expression was downregulated in the early periods of wound healing, with upregulation of bFGF then occurring at a later stage of wound healing. At the same time, the wound dressing decreased the levels of tumor necrosis factor‐α and interleukin‐6, thus validating its beneficial effect on the wound healing process at a biomolecular level. In conclusion, this new hydrogel dressing was shown to exhibit excellent self‐regulatory and anti‐adhesive properties that synergistically promote the healing of burn wounds in rats, thus providing promising results that may have clinical applications. © 2018 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater 107B: 1471–1482, 2019. [ABSTRACT FROM AUTHOR]

Abstract: The discovery of highly efficient photocatalysts for water splitting remains a challenge of high importance. Here, we report a series of novel organic conjugated polymers (OCPs) that contain complexed non‐noble metals for photocatalytic hydrogen evolution. The conjugated chromophore polymers were synthesized by a Heck coupling between ferrocene and phenantholine derivatives, which absorb broadly, even up to the near‐IR region. The photocatalyst performances were investigated for hydrogen evolution by using Fe3(CO)12 as a water reduction catalyst. H2 evolution rates up to 212.4 μmol h−1, with an apparent quantum yield of 10.3 % at 380 nm, were obtained with a photocatalyst polymer based on alternating ferrocene and 4,7‐bisphenyl‐1,10‐phenanthroline units. The high activity is likely due to favorable electron transfer and coordination of Fe3(CO)12 with phenanthroline in the supramolecular OCPs. [ABSTRACT FROM AUTHOR]

Background: Gingipains are cysteine proteases produced by Porphyromonas gingivalis, the predominant pathogen in chronic periodontitis. The present study aims to examine the role of gingipains in promoting apoptosis in osteoblasts.Methods: Human calvarial osteoblasts and osteoblast MC3T3-E1 cells were treated with 8.348 U/L gingipains. Flow cytometry analysis and terminal deoxynucleotidyl transferase-mediated deoxy-UTP nick end labeling staining were used to detect cell apoptosis. Protein expression was examined by Western blotting, and gene expression was detected by real-time polymerase chain reaction. Small interfering (si)RNA transfection was used to knock down BH3-interacting domain death agonist (Bid) expression.Results: Treatment with 8.348 U/L gingipains from 4 to 72 hours increased apoptosis, accompanied by elevated cleaved caspase-3 levels. Notably, gingipain-induced apoptosis was associated with increase of Bid and its truncated form, tBid, as well as p53. Transfection with Bid siRNA resulted in suppression of gingipain-induced apoptosis. The p53 inhibitor, Pifithrin-α, blocked the gingipain-induced Bid. The ability of gingipains to stimulate p53 and Bid expression was mimicked by PD-0325901 and MK-2206, the specific extracellular signal-regulated protein kinases (ERK) and protein kinase B (PKB) inhibitors, respectively. Furthermore, treatment with gingipains reduced phospho-ERK and phospho-PKB levels, an effect correlated to gingipain-induced increase in p53 and tBid expression.Conclusion: The present findings suggest that Bid plays an essential role in gingipain-induced osteoblast apoptosis, which is dependent on inhibition of ERK and PKB phosphorylation, followed by the activation of p53. [ABSTRACT FROM AUTHOR]

A series of phenanthroline-based ligands have been synthesised and their influence as bidentate nitrogen ligands in heteroleptic [Cu(P^P)(N^N)]+ photosensitisers in light-driven water reduction has been studied. In this noble-metal-free Cu-Fe-based photocatalytic water reduction system, the structural effects of the nitrogen ligands have been explored, including the steric and electronic effects of substituents at the 2,9- and 4,7-positions of phenanthroline. Ligands were prepared that led to increased hydrogen generation, with turnover numbers (TONCu) of up to 1388 being observed. All the new complexes were electrochemically and photophysically characterised. We demonstrate for the first time that the presence of fluorine in nitrogen ligands increases the efficacy of copper complexes in photocatalytic hydrogen production. [ABSTRACT FROM AUTHOR]

ABSTRACT Pursuit of robust antifouling coatings is a persistent objective for marine materials. We present here the experimental realization of a series of polyacrylamide-based resins with a self-generating hydrogel layer, arising from the polymerization of acrylamide (AM), butyl acrylate, methacrylic acid, and AM derivatives. The mechanical strength and thermal stability are markedly enhanced due to the change of the structure of modified resins. The preliminary results indicate that resultant resins with crosslinking structure show satisfactory abrasion resistance and swelling properties. The results of antifouling panel testing in shallow submergence for three months reveal that the addition of AM derivatives leads to generation of a thin soft and dynamic layer of hydrogel, which enhances antifouling properties. The formation of hydrogel and self-generating property make it promising in various antifouling applications. © 2016 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2016, 133, 44111. [ABSTRACT FROM AUTHOR]

In situ generated iron-based Knölker complexes were found to be efficient catalysts in a fully non-noble metal Cu-Fe photocatalytic water reduction system. These mononuclear iron catalysts were able to generate hydrogen up to 15 times faster than previously reported [Fe3(CO)12]. A reductive quenching mechanism was shown to operate by fluorescence experiments. [ABSTRACT FROM AUTHOR]

ABSTRACT This work describes the design, fabrication, and testing of an Archimedean spiral or spiral antenna using polymer extrusion 3D printing of polycarbonate base material. The spiral antenna design was simulated using CST Microwave Studio®, and the resulting 3D printed antenna characterized in terms of return loss, directivity, and polarization. The antenna design was embedded into a 3D printed structure using a unique ultrasonic method while a ground plane was inserted through a thermal embedding process. These fabrication methods provide process flexibility , which allows multiple conductive antenna layers to be additively constructed in a single build sequence. The method described can be used to create unique electromagnetic structures such as waveguides directly in a 3D printed dielectric part. The spiral antenna was tested with three variations of microstrip feed line used to match 50Ω impedance and introduce a 180° phase shift between the two arms of the spiral. These include a Duroid balun attached to feed of the antenna after fabrication, a Duroid balun embedded into the polycarbonate during fabrication, and the same microstrip design fabricated out of copper mesh and embedded into the structure using the polycarbonate as a dielectric substrate. The results of these three approaches will be discussed. © 2016 Wiley Periodicals, Inc. Microwave Opt Technol Lett 58:1662-1666, 2016 [ABSTRACT FROM AUTHOR]

Four dinuclear copper( II) complexes, Cu2( L1 -4)4·( CH3OH)2( 1-4) ( HL1 = m-anisic acid, HL2 = p-anisic acid, HL3 = m-toluic acid, HL4 = p-toluic acid) were synthesized and characterized by IR spectroscopy, elemental analysis, and X-ray powder and single crystal diffraction. All of the complexes are consisting of two Cu( II) cations, four L ligands and two methanol molecules, in which the L ligands are coordinated with copper cations by bidentate bridging coordination mode. There exists hydrogen bond interaction or CH...π interaction in the complexes, forming three-dimensional network structures. Theoretical study of the complexes was carried out by density functional theory B3LYP method. [ABSTRACT FROM AUTHOR]

Four dinuclear copper( II) complexes, Cu2( L1 -4)4·( CH3OH)2( 1-4) ( HL1 = m-anisic acid, HL2 = p-anisic acid, HL3 = m-toluic acid, HL4 = p-toluic acid) were synthesized and characterized by IR spectroscopy, elemental analysis, and X-ray powder and single crystal diffraction. All of the complexes are consisting of two Cu( II) cations, four L ligands and two methanol molecules, in which the L ligands are coordinated with copper cations by bidentate bridging coordination mode. There exists hydrogen bond interaction or CH...π interaction in the complexes, forming three-dimensional network structures. Theoretical study of the complexes was carried out by density functional theory B3LYP method. [ABSTRACT FROM AUTHOR]

Insulin-like growth factor-1 (IGF-1) is a brain-specific multifunctional protein involved in neuronal polarity and axonal guidance. Mature IGF-1 triggers three enzymes, mitogen-activated protein kinase (MAPK), phosphatidylinositol 3-kinase (PI3K), and phosphoinositide phospholipase C-γ (PLC-γ), which are its predominant downstream regulators. The PI3K-AKT signaling pathway is upstream of the mammalian target of rapamycin (mTOR), which is of great importance in the induction of autophagy. However, whether the neuroprotective effect of IGF-1 against excitotoxicity is mediated by autophagy through the PI3K/AKT/mTOR pathway remains to be elucidated. The induction of autophagy following NMDA treatment was determined by microtubule-associated protein light chain 3 (LC3) conversion and the result of this autophagy was assessed by monitoring the cleavage of caspase 3 in cultured hippocampal neurons. Cell viability was determined using MTT and LDH assay, and PI-staining was used to estimate the fate of autophagy and the protective effect of IGF-1. In addition, IGF-1 was found to decrease autophagy induced by NMDA using transmission electron microscopy and MDC staining. The protective effect of IGF-1 against autophagy was accompanied with up-regulation of phospho-AKT (p-AKT) and phospho-mTOR (p-mTOR), which was blocked by the inhibitor of PI3K. At the same time, the activation of NR2B resulting in the down-regulation of p-AKT and p-mTOR was blocked by IGF-1. Together, these data suggest that NMDA induces the autophagy, followed by apoptosis in cultured hippocampal neurons, and that IGF-1 can block this effect via inhibition of NR2B receptors and activation of the PI3K-AKT-mTOR pathway. J. Cell. Physiol. 229: 1618-1629, 2014. © 2014 Wiley Periodicals, Inc. [ABSTRACT FROM AUTHOR]

A detailed experimental investigation on the dynamic fracture of a cylindrical shell with internal and external grooves subjected to internal explosive loading was carried out. Distributions of fragment velocities and fragment masses were measured and analyzed for specimens with different depths of the external grooves and different explosive materials, with the internal grooves of a fixed rectangular shape. Based on the experimental results, corresponding numerical simulations using the commercial software LS-DYNA were undertaken. By inspecting the fragments recovered from the experiments and the numerical results, the dynamic fracture of the casing led to fragments of approximately three shapes: a large cuboid fragment, a small cuboid fragment, and two irregular fragments formed by three classical fracture trajectories. The formation mechanism of fragment shapes was analyzed using the fracture trajectories. A good agreement has been obtained between the numerical and experimental results. Finally, a parametric study for the casing thickness, grid patterns of the grooves and explosive materials was carried out in order to investigate the effects of fracture. The results showed that grid patterns of grooves and explosive materials had significant effects on the fracture mechanism of the casing. The numerical technique was used to predict the dynamic fracture of casing with internal and external grooves under internal explosive loading and for structural design in order to achieve desirable fragments with controlled shapes. [ABSTRACT FROM AUTHOR]

Background Endothelial dysfunction is an early event of cardiovascular disease in type 2 diabetes ( T2D) and can occur before albuminuria. Oxidative stress has been found to play a key role in the development of endothelial dysfunction. Therefore, we hypothesized that increases in plasma advanced oxidized protein products ( AOPPs), a family of oxidized, dityrosine-containing protein compounds generated during oxidative stress, could serve as an early marker of endothelial dysfunction in T2D patients without albuminuria. Methods We conducted a cross-sectional investigation of 147 newly diagnosed T2D patients (112 without albuminuria and 35 with albuminuria) and 49 age-matched healthy control subjects. Flow-mediated vasodilation ( FMD) was used to assess endothelium-dependent vasodilator function, and plasma soluble intercellular adhesion molecule-1 ( sICAM-1) concentrations were determined to evaluate vascular injury. Plasma AOPPs concentrations were measured using a modified spectrophotometric assay. Results Plasma AOPPs concentrations were significantly elevated in normoalbuminuric patients with T2D compared with healthy controls. Plasma AOPPs concentrations were correlated with FMD and plasma sICAM-1 concentrations in this population. Multivariate regression analysis demonstrated that increased plasma AOPPs was the strongest risk factor for impaired endothelial vasodilation and increased sICAM-1 in these patients. Similar results were observed in T2D patients with albuminuria. Conclusions Increased plasma AOPPs concentrations were an independent risk factor for endothelial dysfunction, and therefore may be an early marker of vasculopathy in individuals at an early stage of diabetes. [ABSTRACT FROM AUTHOR]

The high incidence of recurrence and the poor prognosis of hepatocellular carcinoma ( HCC) necessitate the discovery of new predictive markers of HCC invasion and prognosis. In this study, we evaluated the expression pattern of two members of a novel oncogene family, Musashi1 ( MSI1) and Musashi2 ( MSI2) in 40 normal hepatic tissue specimens, 149 HCC specimens and their adjacent non-tumourous tissues. We observed that MSI1 and MSI2 were significantly up-regulated in HCC tissues. High expression levels of MSI1 and MSI2 were detectable in 37.6% (56/149) and 49.0% (73/149) of the HCC specimens, respectively, but were rarely detected in adjacent non-tumourous tissues and were never detected in normal hepatic tissue specimens. Nevertheless, only high expression of MSI2 correlated with poor prognosis. In addition, MSI2 up-regulation correlated with clinicopathological parameters representative of highly invasive HCC. Further study indicated that MSI2 might enhance invasion of HCC by inducing epithelial-mesenchymal transition ( EMT). Knockdown of MSI2 significantly decreased the invasion of HCC cells and changed the expression pattern of EMT markers. Moreover, immunohistochemistry assays of 149 HCC tissue specimens further confirmed this correlation. Taken together, the results of our study demonstrated that MSI2 correlates with EMT and has the potential to be a new predictive biomarker of HCC prognosis and invasion to help guide diagnosis and treatment of post-operative HCC patients. [ABSTRACT FROM AUTHOR]

Fluid flow in single fractures with non-uniform apertures is an important research subject in many disciplines. The abruptly changing aperture is a special case of such non-uniformity. This paper simulates water flow in a single fracture with abruptly changing aperture (SF-ACA) using the Lattice Boltzmann Method (LBM) and the Finite Volume Method (FVM). The flow occurs with the Reynolds number ( Re) ranging from 5 to 900 and a ratio of aperture change ( E) of 3 ( E = D/d, where D and d are the larger and smaller apertures, respectively). For Re values between 5 and 100, both LBM and FVM can successfully simulate the eddy development in the expansion regime of an SF-ACA. Flow with high Re values (up to 900) is simulated by FVM, which appears to be numerically more stable than LBM for high- Re flow problems studied here. The flow symmetry in the expansion regime breaks at the Re value between 400 and 500. Our simulation result shows a linear relationship between l1/ d and Re at low Re (5-100) or higher Re (110-900) values, where defined as the length from the location of abrupt expansion to the right edge of the first eddy along the flow direction. If considering the simulation results for the entire simulated range of Re (5-900), the l1/ d-Re relationship is better described by a non-linear logarithmical function. The l1/ d approaches an asymptotic constant at large Re. Copyright © 2011 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

ABSTRACT: Aim: Whether the burden of advanced oxidation protein products (AOPP) accumulation, a marker of oxidative stress, is affected by dialysis modality remains unclear. We compared the serum levels of AOPP in patients on haemodialysis (HD) and continuous ambulatory peritoneal dialysis (CAPD) and tested the hypothesis that an accumulation of AOPP was an independent risk factor for cardiovascular disease. Methods: This was a cross-section study. A total of 2095 patients (1539 HD, 556 CAPD) were recruited from the nine largest dialysis centres in China. Persons in medical centres for disease screening were selected as controls. Patients maintained on HD were dialyzed twice or thrice weekly. CAPD patients used lactate-buffered, glucose-containing solutions. The patients' data were abstracted from the medical record. The serum levels of AOPP were determined by spectrophotometric detection. Results: The levels of AOPP were significantly elevated in both HD and CAPD patients compared to healthy controls. Accumulation of AOPP was more significant in HD compared to CAPD population. Meanwhile, AOPP accumulation was associated with the presence of ischaemic heart disease (IHD) only in HD, but not CAPD patients. A higher proportion of IHD was found in the HD population among those with higher levels of AOPP in each category of age and irrespective of the presence or absence of high triglyceride. Multivariate regression analysis indicated that accumulation of AOPP was an independent risk factor for IHD in HD population. Conclusion: Accumulation of AOPP was more significant in HD compared to CAPD patients. The level of AOPP was independently associated with IHD only in HD patients. [ABSTRACT FROM AUTHOR]

Purpose: To investigate how to label macrophages in atherosclerotic plaques with superparamagnetic iron oxide (SPIO) nanoparticles and trace SPIO with MR imaging. Materials and Methods: Atherosclerotic lesions of a rabbit model were induced by a combination of high-fat and high-cholesterol diet and subsequent endothelial abrasion of the abdominal aorta. SPIO particles were pretreated with poly-L-lysine. SPIO nanoparticles and SPIO-labeled human endothelial cells (ECV-304) were IV injected into model animals, respectively. The MRI scans and histopathological examination were performed 12 h and 24 h after the injection. The imaging and histopathological data were analyzed. Results: Prussian blue staining of the vessel specimens indicated that SPIO particles were not found in the atheroma but in the Kupffer's cells of the liver after SPIO injection. However, the accumulation of SPIO particles in the atheroma was confirmed in animals received SPIO-labeled endothelial cell transplantation. The best quality MR scan sequences of rabbit abdominal aorta were T2WI fat suppression, T1WI, and DIR series, on which of MR image had a higher quality. Signal loss of the original incrassate plaque in the vessel wall on T2WI was found in 6 of 10 animals received SPIO-labeled endothelial cell transplantation. Conclusion: SPIO-labeled endothelial cells were superior to SPIO for MR imaging of atherosclerotic plaques. J. Magn. Reson. Imaging 2011;. © 2011 Wiley Periodicals, Inc. [ABSTRACT FROM AUTHOR]

Background We recently expressed a potent and noncytotoxic short hairpin (sh)RNA directed against chemokine (c-c motif) receptor 5 (CCR5) using lentiviral mediated transduction of CD34+ hematopoietic progenitor cells (HPCs) and demonstrated the stable reduction of CCR5 expression in T-lymphocytes. Methods In the present study, we further assessed the activity of the shRNA through HPC transduction and differentiation into macrophages derived from fetal liver CD34+ (FL-CD34+) HPCs. Transduced lentiviral vector encoding the human CCR5 shRNA was stably maintained in FL-CD34+ cells and in the terminally differentiated macrophages using macrophage colony-stimulating factor, granulocyte macrophage colony-stimulating factor, interleukin-3 and stem cell factor. Results Quantitative real-time polymerase chain reaction for CCR5 mRNA indicated over 90% reduction of CCR5 mRNA levels in CCR5 shRNA-transduced population. The cells with knockdown of CCR5 expression acquired resistance to R5 tropic HIV-1 NFN-SX strain. We also developed a novel approach utilizing a mCherry-CCR5 chimeric reporter to assess the effectiveness of CCR5 target down-regulation in macrophages directly. Both the shRNA and the reporter were maintained throughout HPC differentiation to macrophages without apparent cytotoxicity. Conclusions The present study demonstrates a novel method to simply and directly assess the function of small interfering RNA and the effective inhibition of HIV-1 infection by a potential potent shRNA to CCR5 delivered into macrophages derived from HPCs. Copyright © 2010 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Background Conventional gene-therapy applications of hematopoietic stem cells (HSCs) involve purification of CD34+ progenitor cells from the mobilized peripheral blood, ex vivo transduction of the gene of interest into them, and reinfusion of the transduced CD34+ progenitor cells into patients. Eliminating the process of purification would save labor, time and money, while enhancing HSCs viability, transplantability and pluripotency. Lentiviral vectors have been widely used in gene therapy because they infect both dividing and nondividing cells and provide sustained transgene expression. One of the exceptions to this rule is quiescent primary lymphocytes, in which reverse transcription of viral DNA is not completed. Methods In the present study, we tested the possibility of targeting CD34+ progenitor cells within nonpurified human mobilized peripheral blood mononuclear cells (mPBMCs) utilizing vesicular stomatitis virus G (VSV-G) pseudotyped lentiviral vectors, based on the assumption that the CD34+ progenitor cells would be preferentially transduced. To further enhance the specificity of vector transduction, we also examined utilizing a modified Sindbis virus envelope (2.2) pseudotyped lentiviral vector, developed in our laboratory, that allows targeted transduction to specific cell receptors via antibody recognition. Results Both the VSV-G and 2.2 pseudotyped vectors achieved measurable results when they were used to target CD34+ progenitor cells in nonpurified mPBMCs. Conclusions Overall, the data obtained demonstrate the potential of ex vivo targeting of CD34+ progenitor cells without purification. Copyright © 2009 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Background Epidemiological evidence has indicated that vitamin D deficiency increased the risk of insulin resistance in metabolic syndrome. The present study was conducted to test the hypothesis that 1,25-dihydroxyvitamin D may improve the free fatty-acid (FFA)-induced insulin resistance in muscle cells. Method The insulin resistance of muscle cell model was established by treatment of FFA in differentiated C2C12 cells. Glucose uptake of C2C12 myotubes was analysed by the 3H-labelled 2-deoxyglucose uptake assay. The diameter of myotubes was measured under the condition of glutaraldehyde-induced autofluorescense. Tyrosine phosphorylated insulin receptor substrate 1 (IRS-1) was measured by immunoprecipitation. Serine phosphorylated IRS-1 and protein kinase B (Akt), extracellular signal-related kinase (ERK), c-Jun amino-terminal kinases (JNK) as well as their phosphorylated form were analysed by Western blots. Results Compared with a vehicle-treated group, FFA treatment in myotubes was associated with 70.6% reduction in insulin-mediated uptake of glucose, a five-fold increase in serine phosphorylation of IRS-1, 76.9% decrease in tyrosine phosphorylation of IRS-1 and 81.8% decrease in phosphorylation of Akt. Supplement of 1,25-dihydroxyvitamin D improved the FFA-induced inhibition of glucose uptake in a dose- dependent ( p < 0.001) and time-dependent manner ( p < 0.01). This was accompanied by increase in tyrosine phosphorylation of IRS-1 and phosphorylated Akt and decrease in serine phosphorylation of IRS-1 ( p < 0.001). 1,25-Dihydroxyvitamin D also inhibited the FFA-induced reduction in myotube diameter by 35.3% ( p < 0.001). JNK phosphorylation was reduced by 126.7% with treatment of 1,25-dihydroxyvitamin D ( p < 0.001). 1,25-Dihydroxyvitamin D had no effect on FFA-induced ERK phosphorylation ( p = 0.84). Conclusion 1,25-Dihydroxyvitamin D improved the FFA-induced insulin resistance in muscle cells. Copyright © 2008 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]