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Marine plastic pollution has garnered substantial attention, but the potential endocrine disrupting effects of plastic leachates in marine organisms remain unclear. In this study, the larvae of marine medaka (Oryzias melastigma) were exposed to the leachates from virgin and aged plastics soaked in simulated seawater and fish digest for 3 days. The concentrations of vitellogenin (VTG), estradiol (E2), and 11-ketotestosterone (11-KT), as well as the transcripts of endocrine-related genes were measured in the larvae. The results revealed that endogenous E2 was more sensitive to plastic leachates than VTG and 11-KT, which was significantly affected by 26.7 % of all plastic leachates. Among all genes, estrogen receptor α was impacted mostly, being up-regulated by 53.3 % of leachates from aged plastics. The comparative results demonstrated that the leachates from plastics with different statuses caused a greater difference than those from plastics in different simulated media, and the leachates from aged plastics resulted in higher endocrine disrupting effects than those from virgin plastics. In addition, seven leached additives (plasticizers and flame retardants) could explain 25.6 % of the hormonal effects using redundancy analysis, indicating that other additives in the plastic leachates can also play important roles in regulating the endocrine system of O. melastigma larvae.

Cardiovascular diseases are the leading cause of morbidity and mortality throughout the world underlining the importance of efficient treatments including disease modeling and drug discovery by cardiac tissue engineering. However, the predictive power of these applications is currently limited by the immature state of the cardiomyocytes. Here, we developed gelatin hydrogels chemically crosslinked by genipin, a biocompatible crosslinker, as cell culture scaffolds. Neonatal rat cardiomyocytes appear synchronous beating within 2 days after seeding on hydrogels. Furthermore, we applied the electrical stimulation as a conditioning treatment to promote the maturation of cardiomyocytes cultured on the hydrogels. Our results show that electrical stimulation improves the organization of sarcomeres, establishment of gap junctions, calcium-handling capacity and propagation of pacing signals, thereby, increase the beating velocity of cardiomyocytes and responsiveness to external pacing. The above system can be applied in promoting physiological function maturation of engineered cardiac tissues, exhibiting promising applications in cardiac tissue engineering and drug screening.

The field of cardiac tissue engineering has made significant strides in therapeutic and pharmaceutical applications, highlighted by the development of smart biomaterials. Scaffolds with appropriate properties mimicking the nature of a heart matrix will be highly beneficial for cardiac tissue engineering. In this study, high-aspect-ratio water-dispersed gold nanowires (AuNWs) were synthesized and incorporated into gelatin methacrylate (GelMA) hydrogels, demonstrating enhanced electrical conductivity and mechanical properties of the biomaterial scaffolds. Cardiac cells cultured on GelMA-AuNW hybrid hydrogels exhibited better biological activities such as cell viability and maturation state compared to those cultured on GelMA hydrogels. Moreover, cardiomyocytes showed synchronous beating activity and a faster spontaneous beating rate on GelMA-AuNW hybrid hydrogels. Our strategy of integrating high-aspect-ratio water-dispersed gold nanowires within gelatin methacrylate hydrogels provides a favorable biomaterial scaffold to construct functional cardiac tissue for further applications in cardiac tissue engineering and drug screening.

Three-dimensional (3D) cell culture using hydrogel scaffolds can closely resemble the natural extracellular matrix (ECM), which offers appropriate mechanical support for cells and regulates cellular behavior. In this study, a bacterial transpeptidase sortase A (SA) is used to prepare enzymatically cross-linked methacrylated hyaluronic acid (HA) peptides (HAMA-P) hydrogel, which reveals fast gel kinetics under high SA cross-linking concentrations and can be used as an injection hydrogel for tissue repair or extrusive 3D bioprinting. Furthermore, methacrylated gelatin (GelMA) is introduced to build the hybrid hydrogel (HAMA-P-GelMA) with double cross-linking of enzyme-UV, which has shown proper physical properties (mechanical properties, swelling, degradation rate, etc.) of the hydrogel matrix, and displayed desirable effects on cell viability, adhesion, and cell spreading, when compared to GelMA or HAMA-P single-network hydrogels. The HAMA-P-GelMA hybrid hydrogels provide a favorable 3D milieu for cell growth and can be used as a 3D bio-ink or a carrier of stem cells/cytokines for injectable tissue repair and filling.

In recent years, the ecological risks of plastics to marine environments and organisms have attracted increasing attention, especially the leachates from plastics. However, a comprehensive knowledge about the leaching characteristics and subsequent toxicological effects of leachates is still sparse. In this study, 15 different plastic products were immersed in simulated seawater and fish digest for 16 h. The leachates were analyzed through non-target and target analyses and their toxicological signatures were assessed by bioassays. In total, 240 additives were identified from the plastic leachates, among which plasticizers represented the most (16.7%), followed by antioxidants (8.7%) and flame retardants (7.1%). Approximately 40% of plastic leachates exhibited significant inhibitory effects on the bioluminescence using a recombinant luminescent assay. In addition, both the hyperactive and hypoactive behaviors were displayed in the larvae of marine medaka (Oryzias melastigma) exposed to some plastic leachates. In general, the number and amount of identified compounds under simulated fish digest were less than those under simulated seawater. However, the simulated fish digest leachates triggered higher toxicity. Redundancy analysis demonstrated that identified additives did not adequately explain the toxicological effects. Future research should focus on the identification of more additives in the plastic leachates and their potential ecological risks.

The effects of electropulsing-assisted ultrasonic surface rolling process on surface mechanical properties and microstructure evolution of commercial pure titanium were investigated. It was found that the surface mechanical properties were significantly enhanced compared to traditional ultrasonic surface rolling process (USRP), leading to smaller surface roughness and smoother morphology with fewer cracks and defects. Moreover, surface strengthened layer was remarkably enhanced with deeper severe plastic deformation layer and higher surface hardness. Remarkable enhancements of surface mechanical properties may be related to the gradient refined microstructure, the enhanced severe plastic deformation layer and the accelerated formation of sub-boundaries and twins induced by coupling effects of USRP and electropulsing. The primary intrinsic reasons for these improvements may be attributed to the thermal and athermal effects caused by electropulsing treatment, which would accelerate dislocation mobility and atom diffusion.

The development of diversified biomaterials in tissue engineering has been promoted by growing research into carbon-based nanomaterials. Usually, ideal scaffold materials should possess properties similar to the extracellular matrix of natural myocardial tissue. In this study, dopamine-reduced graphene oxide (GO), was prepared and doped into gelatin methacrylate (GelMA) hydrogels, resulting in novel conductive and mechanical properties for controlling cell growth. Cardiomyocytes (CMs) cultured on PDA-rGO-incorporated hydrogels (GelMA-PDA-rGO) had greater cytocompatibility than those cultured on GelMA hydrogels, as evidenced by higher cell survival rates and up-regulation of cardiac-relevant proteins. Finally, electrical stimulation was applied to facilitate the maturation of CMs which was seeded on different hydrogels. The findings revealed that electrical stimulation of conductive hybrid hydrogel scaffolds improved the orientational order parameter of sarcomeres (OOP). In addition, propagation of intercellular pacing signals, which improves the expression of gap junction proteins was noticed, likewise calcium handling capacity was present in conductive hybrid hydrogels compared to those in pure GelMA group. This study has shown that the combination of GelMA-PDA-rGO based conductive hydrogels and electrical stimulation possessed synergistic effects for engineering a more functional and mature myocardium layer as well as further application in drug screening and disease modeling in vitro.

The proton-conducting materials have potential application in devices such as fuel cells. In this study, a mineral kaolinite-based proton conducting material, kaolinite-4-amidinopyridinium hydrochloride (K-4-APy–HCl), was synthesized by the intercalated compound kaolinite-4-amidinopyridine (K-4-APy) adsorbing volatilizing HCl. The thermogravimetric analysis (TG), powder X-ray diffraction (PXRD) and IR spectrum confirmed the HCl successfully inserting into the interlayer space of kaolinite and the 4-aminopyridine being protonated. The intercalation efficiency is estimated to be ca. 85.6%. With respect to K-4-APy, the interlayer space expends by 1.53 A. The thermal decomposition mechanism was studied by PXRD and TG techniques. The K-4-APy–HCl shows proton conductivity with σ=3.379×10−8 S cm−1 at 373 K and Ea=1.159 eV in the anhydrous condition, which are comparable to MOFs-based proton conducting materials.

To study the role of adenosine A2A receptor (A2AR) in mediating the anti-inflammatory effect of electroacupuncture (EA) on synovitis in collagen-induced arthritis (CIA), C57BL/6 mice were divided into five treatment groups:Sham-control, CIA-control, CIA-EA, CIA-SCH58261(A2ARantagonist), andCIA-EA-SCH58261. All mice except those in theSham-controlgroup were immunized with collagen II for arthritis induction. EA treatment was administered using the stomach 36 and spleen 6 points, and stimulated with a continuous rectangular wave for 30 min daily. EA treatment and SCH58261 were administered daily from days 35 to 49 (n=10). After treatment, X-ray radiography of joint bone morphology was established at day 60 and mouse blood was collected for ELISA determination of tumor necrosis factor alpha (TNF-α) levels. Mice were sacrificed and processed for histological examination of pathological changes of joint tissue, including hematoxylin-eosin staining and immunohistochemistry ofA2ARexpression. EA treatment resulted in significantly reduced pathological scores, TNF-αconcentrations, and bone damage X-ray scores. Importantly, the anti-inflammatory and tissue-protective effect of EA treatment was reversed by coadministration of SCH58261. Thus, EA treatment exerts an anti-inflammatory effect resulting in significant protection of cartilage by activation ofA2ARin the synovial tissue of CIA.

The intercalated kaolinite with potassium acetate (K-KAc), with ca. 91.9% intercalation ratio, was prepared. Thermogravimetric and variable-temperature X-ray powder diffraction analyses disclosed that a small amount of water is easily absorbed into the interlayer space of the K-KAc. The previously reported phase with the 14.2 Å interlayer distance is actually the hydrous K-KAc, which has an approximate formula of Al2Si2O5(OH)4·0.5KAc·0.25H2O. The crystal structures of hydrous and anhydrous phases of K-KAc were simulated in the density functional theory framework, demonstrating that the interactions between the K(+) and acetate ions and the inner surface of kaolinite are significantly strengthened in the anhydrous phase with regard to the hydrous phase. The ionic conductivity of K-KAc indicated that the mobility of the interlayer ions is strongly improved by thermal activation and the conductivity increased by four orders of magnitude from 363 to 423 K.

This paper presents a novel omni-directional steering system for electric vehicle. In order to guarantee the stability and the steerability of the electric vehicle, the proposed novel steering system consists of 2 conditional front wheel steering configuration and 4 wheel omni-directional independent steering configuration. The design of the 2 conditional front wheel steering configuration can guarantee the stability and the steerability of the vehicle. And the four wheel independent steering can achieve omni-directional motions such as zero radius turning (ZRT) and later parking (LP). This system was tested in simulation environment, and the last performance evaluation demonstrates the validity of the proposed omni-directional steering system.

Structural and photoluminescence properties of undoped and Ce 3+ -doped novel silicon-oxynitride phosphors of Ba 4− z M z Si 8 O 20−3 x N 2 x ( M =Mg, Sr, Ca) are reported. Single-phase solid solutions of Ba 4− z M z Si 8 O 20−3 x N 2 x oxynitride were synthesized by partial substitutions of 3O 2− →2N 3− and Ba→ M ( M =Mg, Ca, Sr) in orthorhombic Ba 2 Si 4 O 10 . The influences of the type of alkaline earth ions of M , the Ce 3+ concentration on the photoluminescence properties and thermal quenching behaviors of Ba 3 M Si 8 O 20−3 x N 2 x ( M =Mg, Ca, Sr, x =0.5) were investigated. Under excitation at about 330 nm, Ba 3 M Si 8 O 20−3 x N 2 x :Ce 3+ ( x =0.5) exhibits efficient blue emission centered at 400–450 nm in the range of 350–650 nm owing to the 5 d →4 f transition of Ce 3+ . The emission band of Ce 3+ shifts to long wavelength by increasing the ionic size of M due to the modification of the crystal field, as well as the Ce 3+ concentrations due to the Stokes shift and energy transfer or reabsorption of Ce 3+ ions. Among the silicon-oxynitride phosphors of Ba 3 M Si 8 O 18.5 N:Ce 3+ , M =Sr 0.6 Ca 0.4 possesses the best thermal stability probably related to its high onset of the absorption edge of Ce 3+ .

Functional dyspepsia (FD) is a clinical syndrome with chronic gastroduodenal symptoms without noticeable organic or systemic diseases. According to the Rome III consensus, FD can be subdivided into PDS (postprandial distress syndrome) and EPS (epigastric pain syndrome). Neurotransmitters are involved in the development and pathology of FD. However, the expression profiles of neurotransmitters in FD patients are not clear. This study aimed to investigate the expression profile of neurotransmitters in the duodenal mucosa of FD patients.A total of 48 FD patients treated at our hospital were included in this study: 23 patients with PDS and 25 patients with EPS. Another 21 healthy volunteers served as normal controls. The duodenal mucosa was biopsied with gastroscopy and examined with immunohistochemical staining against serotonin, substance P, inducible nitric oxide synthase (iNOS), and vasoactive intestinal peptide (VIP). Mast cells were identified with toluidine blue staining.The duodenal iNOS levels were significantly higher in PDS patients than the normal controls (P0.05). The expression of serotonin, substance P, and VIP did not differ significantly among the groups. Mast cell counts and the percentage of mast cells with degranulation were significantly higher in PDS and EPS patients than normal controls (P0.001) In addition, iNOS expression levels were positively correlated with percentage of degranulating mast cells (r=0.321, P=0.008).In conclusion, duodenal iNOS may be involved in the pathogenesis of PDS.

Background: The best therapy to prevent esophageal variceal (EV) rebleeding in cirrhotic patients who are non-responsive to pharmacological therapy have not been determined. Aims: To evaluate efficacy of a strategy to assign different treatments according to hepatic vein pressure gradient (HVPG) values to prevent EV rebleeding in non-responders. Methods: This study is a non-randomized controlled prospective study. 109 cirrhotic patients with EV bleeding who were non-responders based on two HVPG measurements were enrolled and divided two groups: 55 patients (EVL+β-blocker group) were treated with endoscopic variceal ligation (EVL) and nonselective β-blocker; 54 patients (HVPG-guided group) were treated with EVL and nonselective β-blocker if HVPG ≤ 16 mmHg (low-HVPG), with percutaneous transhepatic variceal embolization (PTVE) if HVPG > 16 mmHg and ≤ 20 mmHg (medium-HVPG), or with transjugular intrahepatic portosystemic shunt (TIPS) if HVPG > 20 mmHg (high-HVPG). Patients were followed up for rebleeding and mortality. Results: The mean follow-up period was 17.0 months; rebleeding was higher in the EVL+β-blocker group than HVPG-guided group (25.5%, 9.3%, P = 0.026); 3-year probability of rebleeding in the EVL+Beta-blocker group increased with elevated levels of HVPG (12.5% vs 46.4% vs 64.9%, χ2 = 11.551, P = 0.003), and 3-year probability of survival was no difference (96.6% vs 85.7% vs 90.9%, χ2 = 2.638, P = 0.267). Rebleeding rate in PTVE group (7.7%) was lower than that in EVL+β-blockergroup with medium-HVPG (35.7%), but there was no difference. Rebleeding rate in TIPS group (7.7%) was lower than that in EVL+β-blockergroup with high-HVPG (45.5%), but there was no difference. Conclusions: HVPG measurement was useful for making decisions to select EVL and Beta-blocker, PTVE or TIPS in secondary prophylaxis. HVPG-guided treatment is feasible and effective in preventing esophageal varices rebleeding.

Our study aims to discuss the correlation between N-acetyltransferase 2 (NAT2) gene polymorphism and cirrhotic portal hypertension in the Chinese population for the purpose of exploring the functional significance of NAT2 gene polymorphism.From June 2010 to February 2014, a total of 212 posthepatitis B cirrhosis patients (the observation group) from the affiliated Shandong Province-owned Hospital of Shandong University diagnosed by needle biopsy of the liver, B ultrasound, or surgical operation were recruited. These 212 patients were divided into a cirrhotic portal hypertension group (PHT(+) group) (130 patients) and a simple liver cirrhosis (LC) group (PHT(-) group) (82 patients), and 172 healthy blood donors were enrolled into the control group. The polymerase chain reaction-restriction fragment length polymorphism method was adopted to detect NAT2 gene polymorphism and some related statistical analysis.In these 212 patients, four mutation alleles in the NAT2 gene (WT, M1, M2, and M3) were detected. The frequency of patients carrying NAT2 slow acetylator genotype in the observation group was higher than that in the control group, but there was no significant difference (p0.05). However, there was a significant difference in the NAT2 slow acetylator genotype frequency between the PHT(+) group and the control group (p0.05). The risk for the occurrence of PHT in NAT2 slow acetylator genotype carriers was more frequent than that in NAT2 rapid acetylator genotype carriers. In addition, the diameters of the portal vein and splenic vein as well as spleen thickness in NAT2 rapid acetylator genotype were obviously bigger than that in the NAT2 slow acetylator genotype.Our study provided empirical evidence that NAT2 gene polymorphism may be correlated to the formation of cirrhotic portal hypertension, and it might be used as a potential biomarker for genetic susceptibility to PHT in Chinese population.

Multiple displacement amplification (MDA) is a new technology for whole genome amplification (WGA), which can generate large amount of high-quality DNA and features high amplification efficiency and fidelity. MDA combined with conventional PCR techniques has been successfully applied for preimplantation genetic diagnosis, which has broaden latter's clinical applications.

In situ TLC/FTIR technique has tremendous potential in the analysis of complex mixtures. However, the progress in this technique was quite slow. The reason is that conventional stationary phase such as silica gel etc. has strong absorption in FTIR spectrum and thus brings about severe interference in the detection of samples. To solve the problem, the authors propose to use barium fluoride fine particles as stationary phase of TLC plate. The reasons are as follows: Barium fluoride wafer has been extensively used as infrared window in FTIR experiments and it has no absorbance in an IR region between 4 000 and 800 cm'. As a matter of fact, the atomic mass of barium and fluoride is quite large, thus the normal vibration of BaF2 lattice is limited in far-IR region and low frequency part of mid-IR region. Therefore, the interference caused by IR absorption of stationary phase can be resolved if BaF2 is used as stationary phase of TLC plate. Moreover, BaF2 is quite stable and insolvable in water and most organic solvents and it will not be dissolved by mobile phase or react with samples in TLC separation. Additionally, decreasing the particle size of BaF2 is very important in TLC/FTIR analysis technique. The reason is two-fold: First, decreasing the particle size of stationary phase is helpful to improving the efficiency of separation by TLC plate; second, decreasing the size of BaFz particle can improve the quality of FTIR spectra by alleviating the problem of light scattering. By optimizing the synthetic conditions, fine particles of barium fluoride were obtained. SEM results indicate that the size of the BaF2 particles is around 500 nm. FTIR spectrum of the BaF2 particles shows that no absorption of impurity was observed. Moreover, the elevation of baseline caused by light scattering is insignificant. The authors have developed a new technique named "settlement volatilization method" to prepare TLC plate without polymeric adhesive that may bring about significant interference in FTIR analysis. Preliminary TLC experiments proved that the TLC plate using BaF2 fine particles as stationary phase can separate rhodamine B from methylene blue successfully. Applications of barium fluoride fine particles as stationary phase have bright perspective in the development of new in-situ TLC/FTIR analysis techniques.

The undoped and Ce3+-doped title compounds are prepared by solid state reactions using Si3N4, SiO2, BaCO3, MgO, CaCO3, SrCO3, and CeO2 as starting materials (BN boat, 1050—1300 °C, N2/5% H2).

Level set method provides powerful numerical techniques for analyzing and solving interface evolution problems based on partial differential equations. It is particularly appropriate for image segmentation and other computer vision tasks. However, there exists noise in every image and the noise is the main obstacle to image segmentation. In level set method, the propagation fronts are apt to leak through the gaps at locations of missing or fuzzy boundaries that are caused by noise. The robust level set method proposed in this paper is based on the adaptive Gaussian filter. The fast marching method provides a fast implementation for level set method and the adaptive Gaussian filter can adapt itself to the local characteristics of an image by adjusting its variance. Thus, the different parts of an image can be smoothed in different way according to the degree of noisiness and the type of edges. Experiments results demonstrate that the adaptive Gaussian filter can greatly reduce the noise without distorting the image and made the level set methods more robust and accurate.