CO-releasing molecules-2 attenuates ox-LDL-induced injury in HUVECs by ameliorating mitochondrial function and inhibiting Wnt/ß-catenin pathway.

Oxidized low-density lipoprotein (ox-LDL) is well known to disrupt normal functionality of endothelium, which plays a prominent role in endothelial dysfunction in many cardiovascular diseases. CO-releasing molecule 2 (CORM-2) is a promising candidate for treatment of cardiovascular diseases. However, it has not been defined whether CORM-2 might improve endothelial injury induced by ox-LDL. The present study was undertaken to determine the regulatory role of CORM-2 in cell injury of ox-LDL-treated human umbilical vein endothelial cells (HUVECs). Our results showed that ox-LDL inhibited the cell proliferation, but promoted apoptosis and release of cytochrome c (cytc) from mitochondrion into cytoplasm, stimulated the cleavage of caspase-3 and mitochondrial permeability transition pore (MPTP) opening. In addition, ox-LDL-incubated HUVECs exhibited excessive reactive oxygen species (ROS), increased protein levels of NADPH oxidase subunits p22phox, p47phox, NOX-2 and activation of Wnt/ß-catenin signaling pathway. However, pretreatment with CORM-2 significantly reduced cell apoptosis, release of cytc from mitochondrion into cytoplasm, MPTP opening and cleavage of caspase-3, suppressed the superoxide anion generation and Wnt/ß-catenin pathway activation in HUVECs response to ox-LDL. Collectively, we provide the evidence that CORM-2 attenuated ox-LDL-mediated endothelial apoptosis and oxidative stress by recovering the mitochondrial function and blocking Wnt/ß-catenin pathway.

Construction of redox-active multilayer film for electrochemically controlled release.

An electrochemically controlled drug release from a redox-active multilayer film is reported. The multilayer film is fabricated by alternate assembly of the electrochemical redox-active micelles and DNA. The buildup of multilayer films is monitored by spectroscopic ellipsometry, UV-vis spectroscopy, and fluorescence spectroscopy. A ferrocene-modified poly (ethyleneimine) (PEI-Fc) is used to form a hydrophobic ferrocene core and hydrophilic PEI shell micelle, showing the electrochemical redox-active properties. Hydrophobic pyrene (Py) molecules are then incorporated into the micelles. The PEI-Fc@Py micelles are assembled into the (PEI-Fc@Py/DNA) multilayer film by layer-by-layer assembly. Thanks to ferrocene groups with the properties of the hydrophilic-to-hydrophobic switch based on the electrical potential trigger, pyrene molecules can be control released from the multilayer film. The electrochemically controlled release of pyrene is investigated and confirmed by electrochemical quartz crystal microbalance and electrochemistry workstation. The (PEI-Fc@drug/DNA) multilayer film may have potential applications in the field of biomedical and nanoscale devices.

A signal amplification for Trp isomers electrochemical recognition based on PEDOT:PSS and CS/PAA multilayers.

In this work, enhanced tryptophan (Trp) isomers recognition was successfully demonstrated on (CS/PAA)3.5@PEDOT:PSS/GCE, a multilayer chiral sensor with good stability and reproducibility. The (CS/PAA)n multilayers chiral interface was first fabricated via alternating self-assembly of chiral chitosan (CS) and achiral polyacrylic acid (PAA). Conductive PEDOT:PSS was then compounded with (CS/PAA)n multilayers to obtain the chiral sensor for the electrochemical recognition of Trp isomers. The structure of the sensor and its chirality properties for Trp isomers were characterized by fourier transform infrared spectroscopy (FT-IR)，scanning electron microscopy (SEM) and electrochemical methods. The SEM images showed uniform distribution of PEDOT:PSS in the multilayer films, which changed the internal structure of the (CS/PAA)3.5. Consequently, (CS/PAA)3.5@PEDOT:PSS multilayers rendered more chiral centers in addition to improved good conductivity, which significantly amplified the oxidation peak current ratio of D-Trp to L-Trp (ID/IL) up to 6.71 at 25 °C. In addition, a linear relationship was observed between the peak current and Trp enantiomer concentration in the range of 0.002-0.15 mM, and the detection limits of D-Trp and L-Trp were 0.33 and 0.67 µM, respectively. More importantly, the percentage of D-Trp in non-racemic Trp enantiomers mixture solutions were successfully determined on the chiral interface, showing its effectiveness and promising potential in practical applications.

Supramolecular assembly induced chiral interface for electrochemical recognition of tryptophan enantiomers.

The ß-CD@PEI-Fc chiral interface was prepared based on the supramolecular host-guest interaction between ferrocene (Fc) grafted polyethyleneimine (PEI-Fc) and chiral ß-cyclodextrin (ß-CD). SEM results show that ß-CD@PEI-Fc interface has a regular spatial structure, which can effectively distinguish tryptophan (Trp) enantiomers. Under the optimal conditions, differential pulse voltammetry shows that the peak current ratio (Id/Il) of Trp enantiomers can reach 2.84 at 15 °C. More interestingly, the ß-CD@PEI-Fc/GCE exhibited chiral recognition of d-Trp and l-Trp via water contact angle measurements. There was a good linear relationship between the peak current and the concentration of Trp enantiomers in the range from 0.005 mM to 0.10 mM. Finally, the chiral interface can be applied for quick detection of the proportion of isomers in Trp racemic solution, which is very important for chiral recognition in racemic mixture of chiral compounds. Meanwhile, the ß-CD@PEI-Fc/GCE showed good stability and reproducibility.

[Indicator Function of Ragworm (Nereididae) on Sediment Microplastic in Haizhou Bay Intertidal Zone].

Sediment samples were collected from nine sites of three sections, in the intertidal zone of Haizhou bay in July 2018. The abundance and characteristics of microplastics in the sediments (and ragworms within the sediments) were then determined to identify the source of microplastics in ragworms, and to explore the effects of ragworms on microplastics in sediment. The average abundance of microplastics in tidal flat sediments was (0.49±0.17) n·g-1, which was at a high level in domestic offshore environmental studies. Among all the microplastics detected, the most common form and color were fiber and black-gray, respectively, and the materials were mainly polyethylene (PE), polyester (PET), and polystyrene (PS). The detection rate of microplastics in ragworm was 77.78%-86.67%, with an average abundance of (6.68±2.21) n·ind-1; the abundance was significantly correlated with individual mass (r=0.42, P=0.002). The microplastic abundance was significantly higher in ragworms with individual mass over 1.5 g than in those with a mass of<0.5 g or 0.5-1 g (F3=141.029, P=0.000). In ragworms, microplastics were dominated by small black or blue fibers, and the main materials were PE and PET. By analyzing the various characteristics of microplastics with a particle size of 0-3 mm, it was found that the abundance of microplastics in sediments was strongly correlated with that in ragworms (r=0.79,P=0.01); the main form (r=0.90, P=0.035) and the material composition (r=0.73, P=0.024) also showed significant correlation between sediments and ragworms. This indicates that ragworms ingest microplastics in the sedimentary environment and exchange the microplastics with the sediments. Therefore, ragworms can be used as an indicator species of microplastic pollution in sediments.

Effects of Incretin-based Therapies on Weight-related Indicators among Patients with Type 2 Diabetes: A Network Meta-analysis.

OBJECTIVE: To evaluate the effects of incretin-based therapies on body weight as the primary outcome, as well as on body mass index (BMI) and waist circumference (WC) as secondary outcomes. METHODS: Databases including Medline, Embase, the Cochrane Library, and clinicaltrials.gov (www.clinicaltrials.gov) were searched for randomized controlled trials (RCTs). Standard pairwise meta-analysis and network meta-analysis (NMA) were both carried out. The risk of bias (ROB) tool recommended by the Cochrane handbook was used to assess the quality of studies. Subgroup analysis, sensitivity analysis, meta-regression, and quality evaluation based on the Grading of Recommendations Assessment, Development, and Evaluation (GRADE) were also performed. RESULTS: A total of 292 trials were included in this study. Compared with placebo, dipeptidyl-peptidase IV inhibitors (DPP-4Is) increased weight slightly by 0.31 kg [95% confidence interval ( CI): 0.05, 0.58] and had negligible effects on BMI and WC. Compared with placebo, glucagon-like peptide-1 receptor agonists (GLP-1 RAs) lowered weight, BMI, and WC by -1.34 kg (95% CI: -1.60, -1.09), -1.10 kg/m 2 (95% CI: -1.42, -0.78), and -1.28 cm (95% CI: -1.69, -0.86), respectively. CONCLUSION: GLP-1 RAs were more effective than DPP-4Is in lowering the three indicators. Overall, the effects of GLP-1 RAs on weight, BMI, and WC were favorable.

Synthesis and investigation of physico-chemical properties of dicationic ionic liquids.

A series of dicationic ionic liquids (ILs) including [C4(MIM)2][PF6]2, [C5(MIM)2][PF6]2, [C6(MIM)2][PF6]2 and [C4(PYR)2][PF6]2 were synthesized. Their thermal stability and melting points were analysed. It was found that dicationic ILs presented important implications in the design of homogeneous and heterogeneous system with water. A homogeneous system of dicationic ILs with water could be formed at a relatively high temperature and then a heterogeneous system was formed when the solution was cooled to a low temperature. The ILs recovered by altering the temperature were obtained in high percentage yields of [C4(MIM)2][PF6]2 (97.6%), [C5(MIM)2][PF6]2 (97.3%), [C6(MIM)2][PF6]2 (98.0%) and [C4(PYR)2][PF6]2 (94.2%). On the other hand, [C4(MIM)2][PF6]2 and [C5(MIM)2][PF6]2 exhibited good solubility in acetonitrile and acetone. A homogeneous system could be achieved with imidazolium-based ILs with a relatively low amount of water and acetonitrile at room temperature. All of the properties of dicationic ILs have a strong correlation with the nature of dications, the linkage chain and the symmetry of dications. Dicationic ILs may provide a new opportunity for some specific applications in order to enable the effective separation and isolation of products.

Screening of potential IL-tolerant cellulases and their efficient saccharification of IL-pretreated lignocelluloses.

Lignocellulosic biomass as one of the most abundant and renewable resources has great potential for biofuel production. The complete conversion of biomass to biofuel is achieved through the effective pretreatment process and the following enzyme saccharification. Ionic liquids (ILs) are considered as a green solvent for lignocellulose pretreatment. However, ILs exhibit an inhibitory effect on cellulase activity, leading to a subsequent decrease in the efficiency of saccharification. The screening of new potential IL-tolerant cellulases is important. In the current study, a fungal strain with a relatively high cellulase production was isolated and identified as Penicillium oxalicum HC6. The culture conditions were optimized using corn stover and peptone as the carbon source and nitrogen source at pH 4.0 and 30 °C with an inoculation size of 2% (v/v) for 8 days. It was found that P. oxalicum HC6 exhibited potential salt tolerance with the increase of the enzyme production at a salt concentration of 5.0% (w/v). In addition, high enzyme activities were obtained at pH 4.0-6.0 and 50-65 °C. The crude enzyme from P. oxalicum HC6 with good thermal stability was also stable in the presence of salt and ILs. Good yields of reducing sugar were obtained by the crude enzyme from P. oxalicum HC6 after the saccharification of corn stover that was pretreated by ILs. P. oxalicum HC6 with potentially salt-tolerant and IL-tolerant enzymes has great potential application in the enzymatic saccharification of lignocellulose.

Direct electrochemistry and electrocatalytic characteristic of heme proteins immobilized in a new sol-gel polymer film.

Heme proteins were immobilized on glass carbon electrodes by poly (N-isopropylac-yamide-co-3-methacryloxy-propyl-trimethoxysilane) (PNM) and exhibited a pair of well-defined, quasi-reversible cyclic voltammetric peaks at about -0.35 V versus a saturated calomel electrode in pH 7.0 buffer solution, corresponding to hemeFe(III)+e-->hemeFe(II). Some electrochemical parameters were calculated by performing nonlinear regression analysis of square wave voltammetry (SWV) experimental data. The formal potential was linearly dependent on pH, indicating the electron transfer of Fe(III)/Fe(II) redox couple accompanied by the transfer of proton. Ultraviolet visible and Fourier transform infrared spectra suggested that the conformation of proteins in the PNM films retained the essential feature of its native secondary structure. Atomic force microscopy images demonstrated the existence of interaction between heme proteins and PNM. N,N-dimethylformamide (DMF) played an important role in immobilizing proteins and enhancing electron transfer between proteins and electrodes. Electrochemical catalytic reductions of hydrogen peroxide and trichloroacetic acid by proteins entrapped in PNM film were also discussed, showing the potential applicability of the film modified electrodes as a biosensor.

Shear wave elastography combined with the thyroid imaging reporting and data system for malignancy risk stratification in thyroid nodules.

To retrospectively evaluate the diagnostic performance of shear wave elastography (SWE) and thyroid imaging reporting and data system (TI-RADS) in differentiating malignant and benign thyroid nodules. A total of 313 thyroid nodules in 227 patients were included. All thyroid nodules were underwent SWE and TI-RADS before fine needle aspiration biopsy and/or surgery. SWE elasticity indices of the maximum (Emax), mean (Emean), minimum (Emin) and elastic ratio (ER) in thyroid nodules were measured. Nodules with solid component, marked hypoechogenicity, poorly defined margins, micro-calcifications, and a taller-than-wide shape were classified as suspicious at gray-scale ultrasonography. The level of TI-RADS was determined according to the number of suspicious ultrasonography features. The combined methods of SWE and TI-RADS in thyroid nodules were calculated. In the 313 nodules, 194 were malignant, and 119 were benign. SWE and TI-RADS were significantly higher in malignant nodules than benign nodules (P < 0.001). The most accurate SWE cut-off value, 51.95 kPa for Emax, achieved a sensitivity of 81.44% and a specificity of 83.19% for discriminating malignant nodules from benign nodules. There are two methods in combination with SWE and TI-RADS. The one is "tandem" method, which has a higher specificity (95.80%), positive likelihood ratio (18.16) and positive predictive value (96.73%). The other one is "parallel" method, which shows sensitivity (94.85%), negative likelihood ratio (0.07) and negative predictive value (90.00%).We believe that the methods could be used as a simple tool to stratify the risk of thyroid nodules accurately.

Galactosylated poly-L-lysine targeted microbubbles for ultrasound mediated antisense c-myc gene transfection in hepatocellular carcinoma cells.

INTRODUCTION: The aim of the study was to investigate the efficiency of delivery and targeted binding of c-myc antisense oligodeoxynucleotide (ASODN) and find a novel therapy for hepatic carcinoma. MATERIAL AND METHODS: A targeted ultrasound microbubble compound was synthesized to deliver the c-myc ASODN by ultrasound-targeted microbubble destruction (UTMD) and applied in hepatocellular carcinoma cells (HCC) and cancer bearing mice. Lipid microbubbles were conjugated with biotinylated galactosylated poly-L-lysine (G-PLL) and SonoVue to target the hepatocellular carcinoma SMMC7721 cells with asialoglycoprotein receptors. There were four groups in both in vitro and in vivo studies: control group (group A); c-myc ASODN + G-PLL (CG group, group B); c-myc ASODN + SonoVue (CUS group, group C); c-myc ASODN + G-PLL + SonoVue (CGUS group, group D). The expression of c-myc mRNA was detected by reverse transcription-polymerase chain reaction (RT-PCR), and proliferation investigations of the SMMC7721 cells were also performed. In addition, the tumor volume was calculated and compared among different groups. RESULTS: The level of c-myc mRNA in the three experimental groups was significantly lower than that in the control group in vitro (p < 0.05). Furthermore, c-myc gene expression was suppressed more strongly in the CGUS group compared with other groups in both in vitro and in vivo studies (p < 0.05). In addition, ultrasound mediation of targeted microbubbles yielded the highest inhibition of tumor growth and cell proliferation among the four groups. CONCLUSIONS: The use of a G-PLL targeted microbubble contrast agent combined with ultrasound exposure could be a potential method for increasing gene delivery efficiency. This technique is a promising nonviral approach that can be used in liver cancer.

In vivo experimental study on the effects of fluid in increasing the efficiency of radiofrequency ablation.

BACKGROUND: Radiofrequency ablation (RFA) is the most widely used and studied method internationally for the local treatment of liver tumors. However, the extension of coagulation necrosis in one RFA procedure is limited and incomplete coverage of the damaged area can lead to a high local recurrence rate. OBJECTIVE: In this study, we compared the effects of different solutions in enhancing hepatic radiofrequency by establishing a rabbit VX2 liver cancer model. We also determined the optimal solution to maximise effects on the extent of RFA-induced coagulation necrosis. METHODS: Thirty VX2 tumor rabbits were randomly assigned to five groups: group A, RFA alone; group B, RFA with anhydrous ethanol injection; group C, RFA with 5% hypertonic saline injection; group D, RFA with lidocaine injection; and group E, RFA with a mixed solution. Routine ultrasound examinations and contrast-enhanced ultrasound (CEUS) of the ablation areas were performed after RFA. Then, we measured the major axis and transverse diameter and compared the areas of coagulation necrosis induced by RFA. RESULTS: The mean ablation area range increased in groups B, C and especially E, and the scopes were greater compared with group A. Preoperative application of anhydrous ethanol, hypertonic saline, lidocaine and the mixed solution (groups B, C, D and E, respectively) resulted in larger coagulation necrosis areas than in group A (p<0.05). Among the groups, the coagulation necrosis areas in group E was largest, and the difference was statistically significant compared with other groups (p<0.05). Pathological findings were consistent with imaging results. CONCLUSIONS: A mixture of dehydrated alcohol, hypertonic saline and lidocaine injected with RFA increases the extent of coagulation necrosis in the liver with a single application, and the mixed solution is more effective than any other injection alone.

Electropolymerization of dopamine for surface modification of complex-shaped cardiovascular stents.

Inspired by the adhesion strategy of marine mussels, self-polymerization of dopamine under alkaline condition has been proven to be a simple and effective method for surface modification of biomaterials. However, this method still has many drawbacks, such as the use of alkaline aqueous medium, low poly(dopamine) deposition rate, and inefficient utilization of dopamine, which greatly hinder its practical application. In the present study, we demonstrate that electropolymerization of dopamine is a facile and versatile approach to surface tailoring of metallic cardiovascular stents, such as small and complex-shaped coronary stent. Electropolymerization of dopamine leads to the formation of a continuous and smooth electropolymerized poly(dopamine) (ePDA) coating on the substrate surface. This electrochemical method exhibits a higher deposition rate and is more efficient in dopamine utilization compared with the typical self-polymerization method. The ePDA coating facilitates the immobilization of biomolecules onto substrates to engineer biomimetic microenvironments. In vitro and in vivo experiments demonstrate that ePDA coating functionalized with vascular endothelial growth factor can greatly enhance the desired cellular responses of endothelial cells and prevent the neointima formation after stent implantation. The proposed methodology may find applications in the area of metallic surface engineering, especially for the cardiovascular stents and potentially all biomedical devices with electroconductive surface as well.

Expression of Fas/FasL in CD8+ T and CD3+ Foxp3+ Treg cells--relationship with apoptosis of circulating CD8+ T cells in hepatocellular carcinoma patients.

AIMS: Dysfunction of the host immune system in cancer patients can be due to a number of factors, including lymphocyte apoptosis. Several studies showed that Foxp3+T cells take part in inducing this process by expressing FasL in tumor patients. However, the relationship between apoptosis, CD8+T cells and Foxp3+T cells in HCC patients is still unclear. The present study was designed to investigate the correlation between apoptosis levels and Fas/FasL expression in CD8+T lymphocytes and Foxp3+T cells in patients with HCC. METHODS: CD8+T cells and CD3+Foxp3+T cells were tested from peripheral blood of HCC patients and normal controls and subjected to multicolor flow cytometry. The expression of an apoptosis marker (annexin V) and the death receptor Fas in CD8+T cells and FasL in CD3+Foxp3+T cells were evaluated. Serum TGF-ß1 levels in patients with HCC were measured by enzyme-linked immunosorbent assay. The relationship between apoptosis and Fas expression, as well as FasL expression in CD3+Foxp3+T cells was then evaluated. RESULTS: The frequency of CD8+T cells binding annexin V and Fas expression in CD8+T cells, were all higher in HCC patients than normal controls and the proportion of apoptotic CD8+T cells correlated with their Fas expression. Serum TGF-ß1 levels correlated inversely with CD3+Foxp3+T cells. CONCLUSIONS: Fas/FasL interactions might lead to excessive turnover of CD8+T cells and reduce anti-tumor immune responses in patients with HCC. Further investigations of apoptosis induction in Fas+CD8+T cells in vitro are required.

Electrochemically controlled stiffness of multilayers for manipulation of cell adhesion.

Stimuli-responsive thin films attract considerable attention in different fields. Herein, an electrochemical redox multilayers with tunable stiffness is constructed through the layer-by-layer self-assembly method. The redox ferrocene modified poly(ethylenimine) play an essential role to induce multilayers' swelling/shrinking under an electrochemical stimulus, resulting reversible change of elastic modulus of the multilayers. The adhesion of fibroblast cells can be thus controlled from well spreading to round shape. Such soft multilayers with electrochemically controlled stiffness could have potentials for cell-based applications.