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Abstract: Aim: To assess the effects of 2‐hydroxyethyl methacrylate (HEMA) on proliferation and migration of human pulp cells, as well as on matrix metalloproteinase (MMP‐2 and MMP‐9) expression in human odontoblast‐like cells, contributing to the goal of determining the relationship between resin materials and MMP activity in pulp–dentine complexes. Methodology: Dental pulp cell cultures were established from pulp tissue of human teeth extracted for orthodontic purposes. Pulp cell differentiation was characterized in the presence of dentine sialophosphoprotein, bone sialoprotein and alkaline phosphatase by reverse transcription polymerase chain reaction. MMP activity was assessed by gelatine zymography with media containing HEMA. Cell viability was evaluated using methyl thiazolyl tetrazolium assay for 24–72 h. Cell migration was tested using Transwell migration assay. Western blotting was used to visualize MMP expression with the nontoxic HEMA concentrations (0–400 μg mL−1) for 48 h. Results: Pulp cell proliferation decreased with HEMA exposure in a time‐ and concentration‐dependent manner. HEMA concentrations ≤400 μg mL−1 did not induce changes in cell viability at 48 h (P < 0.05). Pulp cells were induced to differentiate into odontoblast‐like cells in media containing 5 mg mL−1 ascorbic acid and 10 mmol L−1 β‐sodium glycerophosphate for 3–4 weeks. After incubation with HEMA, dose‐dependent inhibition was observed; HEMA had a strong inhibitory effect on MMP activity. Compared with the control group, cell migration and MMP expression were inhibited significantly with increasing HEMA concentration at noncytotoxic doses (P < 0.05). Conclusions: Cell viability was not affected at HEMA concentrations ≤400 μg mL−1. Within this range, HEMA inhibited MMP‐2 and MMP‐9 expression and activity, which may protect against type I collagen degradation effectively during dentine adhesive procedures. [ABSTRACT FROM AUTHOR]

Haem oxygenase-1 ( HO-1) plays an important role in inflammatory disease development and progression. Whether it has an anti-inflammatory role in lipopolysaccharide ( LPS)-induced liver injury remains unclear. To investigate the functional role of HO-1 in protecting liver tissue against inflammatory response stimulated by LPS in rat and the mechanism by which it achieves this protective effect, LPS-stimulated inflammatory models were established. In pretreatment of rats with HO-1 activator (haemin) or inhibitor (zinc protoporphyrin-9, Zn PP, a specific inhibitor of HO) before LPS stimulation, we evaluated the pathological changes by haematoxylin-eosin staining. The mRNA expression and secretion of IL-1 β and IL-6 in rat liver were analysed using the real-time PCR and ELISA. Real-time PCR and Western blot were also used to evaluate the expression of HO-1, p38 and p-p38 in liver. Liver CO contents were sensitized to the expression of HO-1. Induction of HO-1 by haemin remarkably inhibited the expression of p38, and addition of Zn PP increased this expression. Our results demonstrate that HO-1 is an anti-inflammation factor in LPS-stimulated liver, which regulate the inflammatory response through downregulation of p38 signalling pathways in rat liver. [ABSTRACT FROM AUTHOR]

An enzootic disease characterized by granulomas in internal organs occurred in cage-farmed large yellow croaker, Larimichthys crocea ( Richardson), in April and November 2010, in Ningbo, Zhejiang Province. One bacterial strain, named XSDHY-P, was isolated from the diseased fish and identified by biochemical characterization, fatty acid methyl ester ( FAME) analysis and multilocus sequence analysis ( MLSA). According to the results obtained from the biochemical tests, FAME analysis and phylogenetic analysis derived from 16S ribosomal RNA, gyrB, oprF, oprI, oprL and rpoD gene sequencing, the bacterial isolate, XSDHY-P, was identified as Pseudomonas plecoglossicida. Moreover, lethal dose, 50% trials were carried out to demonstrate the virulence of XSDHY-P in large yellow croaker when administered at 2.13 × 105 colony-forming units per fish. Visceral granulomas were found in the experimentally infected fish as well as in the naturally infected fish, indicating that P. plecoglossicida is another bacterial pathogen that causes granulomatosis in L. crocea. [ABSTRACT FROM AUTHOR]

Extracellular superoxide dismutase (SOD3) is a major antioxidant enzyme that protects organs from damage by reactive oxygen species (ROS). In this study, the SOD3 gene was identified and characterized from the freshwater mussel Hyriopsis cumingii (Hc -SOD3). The cDNA sequence consists of 763 bp, encoding a protein of 208 amino acids. The amino acid sequence possesses two CuZnSOD signature sequences, and amino acids required for binding of Cu (His-93, -95, -110 and -169) and Zn (His-110, -118, -129 and Asp-132) were conserved in Hc -SOD3. The Hc -SOD3 genomic sequence was 9165 bp in length, containing four exons and three introns. Eighteen single nucleotide polymorphisms were detected in the Hc- SOD3 gene from resistant stock (RS) and susceptible stock (SS) of H. cumingii to Aeromonas hydrophila. The genotype and allele distribution were examined in resistant and susceptible stocks. Among them, a C/G substitution at the g.7994C>G locus and G/C substitution at the g.8087G>C locus were significantly associated with resistance/susceptibility of H. cumingii to A. hydrophila, both in genotype ( P = 0.017, P = 0.004 respectively) and allele frequency ( P = 0.021, P = 0.006 respectively). Linkage disequilibrium analysis revealed that g.7994C>G, g.8001A>G, g.8035G>A, g.8087G>C and g.8191T>A were in linkage disequilibrium. The results suggest that the two polymorphic loci, g.7994C>G and g.8087G>C, could be potential genetic markers for future molecular selection of strains that are resistant to diseases. [ABSTRACT FROM AUTHOR]

Multiwall carbon nanotubes supported Pd-Co electrocatalysts (Pd-Co/MWCNTs) for hydrazine electrooxidation in alkaline electrolytes were prepared. Their morphology and structure were characterized by scanning electron microscopy, transmission electron microscope, and X-ray diffraction. The effect of the mass ratio of Pd to Co on the catalytic performance was examined via cyclic voltammetric and chronoamperometric measurements. The Pd-Co/MWCNTs with a mass ratio of 1:1 for Pd:Co shows higher catalytic performance than both Pd/MWCNTs and Co/MWCNTs and it has good stability for catalyzing the electrooxidation of hydrazine. The gas collection measurements indicated that hydrazine electrooxidation on Pd-Co/MWCNTs proceeded via a near 4-electron pathway. [ABSTRACT FROM AUTHOR]

In this work, interconnect/electrode sheet/interconnect sandwiches are assembled by designing interfacial contact between interconnects and electrodes for planar solid oxide fuel cells (SOFCs). Their area specific resistance (ASR) values of different contact methods under isothermal oxidation and thermal cycling are recorded by four-point method. The ASR of SUS430/Ni-YSZ/SUS430 anode sandwich with NiO current collecting layer is close to that of anode sandwich without NiO current collecting layer during isothermal operation, but smaller and more stable during thermal cycling. Meanwhile, the lowest ASR is obtained in SUS430/LSM-YSZ/SUS430 cathode sandwich with LSM coated interconnect and LSM current collecting layer among various contact methods between interconnects and cathodes, and remains constant under isothermal oxidation and thermal cycling. Contact resistance between cathodes and interconnects is the main source of the SOFC stack resistance. A real stack with three anode-supported cells is assembled and tested under thermal cycling to verify the effect of different contact methods between interconnects and electrodes on performance of stack repeating unit. The degradation rate and ASR values of repeating unit inside the stack indicate that the contact between LSM coated interconnect and LSM current collecting layer on cathode side is the optimized contact. [ABSTRACT FROM AUTHOR]

The full-length complementary DNA (cDNA) sequences encoding cd8α and cd8β molecules were sequenced and characterized from mandarin fish Siniperca chuatsi. Conserved motifs and residues were found to be present in derived peptides of the Cd8 molecules. For example, WXR motif, DXGXYXC motif, and four cysteine residues were present in the extracellular region of the Cd8 protein. Threonine, serine and proline residues involved in multiple O-linked glycosylation events were located in the membrane proximal hinge region. The common CPH motif in the cytoplasmic tail was detected similar to other teleost Cd8 molecules. Different from those in mammals, S. chuatsi Cd8 sequences have many extra cysteine residues (C149 in Cd8 α sequence and C46, C51 and C158 in Cd8 β sequence), which also exist in other teleost Cd8 molecules. Real-time polymerase chain reaction (RT-PCR) and Western blot analyses revealed that the thymus had the highest expression of cd8 messenger (m)RNA and protein. After stimulated with phytohaemagglutinin, polyriboinsine-polyribocyaidylic acid and concanavalin A (ConA), the expression level of cd8 mRNA increased significantly in head-kidney lymphocytes at 4 and 8 h, but decreased to normal level at 12 h. Similarly, stimulation with ConA in vivo also led to an increase in the cd8 mRNA level in the spleen. Immunohistochemistry analysis demonstrated that Cd8 α-positive cells can be detected in the thymus, spleen and intestine by using polyclonal anti-Cd8 α antibody. [ABSTRACT FROM AUTHOR]

A Pd-modified hydrogen storage alloy was investigated as the anode electrocatalyst of direct borohydride fuel cell. The modification of the MmNi50.6 Co10.2 Mn5.4 Al1.2 hydrogen storage alloy with Pd was carried out by a self-reduction reaction method. The morphology and the distribution of Pd on the surface of the alloy were observed by scanning electron microscope and energy dispersive X-ray spectrometer. It was found that Pd particles uniformly distributed on the alloy surface and the content of Pd was 0.64 wt.%. The catalytic activity of the Pd-modified hydrogen storage alloy for NaBH4 electrooxidation was evaluated by cyclic voltammetry and chronoamperometry measurements. Results showed that Pd modification significantly enhanced the catalytic activity of the hydrogen storage alloy. In the 1.0 mol dm-3 NaOH+ 0.1 mol dm-3 NaBH4 solution, the stabilized current density at -0.7 V was 34 and 22 mA cm-2 for the pristine and the Pd-modified alloy, respectively. The utilization efficiency of NaBH4 on the Pd-modified alloy catalyst reached 45%, which is higher than that on the pristine alloy (30%). The number of electrons released by BH4- electrooxidation on Pd-modified alloy was found to be close four. [ABSTRACT FROM AUTHOR]

Rapid heat cycle moulding (RHCM) is a newly developed moulding technique to improve the surface appearance of plastic parts and eliminate the polluting secondary operations such as primers and painting. In steam-assisted RHCM, the mould surface temperature should be thermally cycled by alternatively cycling the high temperature steam and cooling water in the heating/cooling channels of the mould. The mould design is of great importance for RHCM because it not only has a great effect on the heating/cooling efficiency and hence the productivity but also directly affects the mould surface temperature uniformity and accordingly the final part quality. Furthermore, the service life of the RHCM mould with steam heating is also very much dependent on the mould structure or the layout of the heating/cooling channels as the fatigue crack is likely to occur at the wall of the heating/cooling channels under combined thermal cycling and mechanical loading. In this study, an RHCM mould for a type of 52-inch LCD TV frame was designed. A three-dimensional (3D) transient thermal analysis was performed to determine the thermal response efficiency of the designed RHCM mould cavity and investigate the factors affecting the heating efficiency. Then, by using the results obtained from the heat transfer simulation, the thermal-structure coupling analysis comprehensively considering the cavity pressure and clamp force was conducted to analyse the stress distribution in the mould cavity, which is helpful to find the weak position in the mould cavity. We found that the spots where the maximum stresses occur are similar to the region where fatigue cracks come into being in the actual RHCM mould. Based on the simulation results, the mechanism of the cavity cracks formation on the cavity surface was proposed. Finally, the fatigue analysis was conducted to predict the fatigue life of the RHCM mould. The analysis results show that the regions at the top edges of the heating/cooling channels have the lowest fatigue life and safety factor. The discrepancy between the available life predicted by simulation and the actual service life of the RHCM mould is also discussed. [ABSTRACT FROM AUTHOR]

An epizootic in seawater-cage reared large yellow croaker, Larimichthys crocea, in China was caused by a Nocardia sp. from August to October 2003. The cumulative mortality rate was 15% and the diseased fish were 16 months old with individual length varying from 25 to 30 cm. Multiple, white nodules, 0.1–0.2 cm in diameter, were scattered on the heart, spleen and kidney. The morphology of isolated bacteria from Lowenstein–Jensen medium and tryptic soy agar was bead-like or long, slender, filamentous rods. Experimental infection indicated that the isolated bacterium was the pathogen responsible for the mortalities. A partial sequence of the 16S rRNA gene of the organism and the type strain of Nocardia seriolae JCM 3360T (Z36925) formed a monophyletic clade with a high sequence similarity of 99.9%. Based on the morphological, physiological, biological properties and the phylogenetic analysis, the pathogenic organism was identified as N. seriolae. This is the first report on N. seriolae-infected large yellow croaker in aquaculture. [ABSTRACT FROM AUTHOR]

A space vector pulse-width modulation (SVPWM) strategy of the post-fault reconfigured dual inverter in open-end winding motor drive systems is discussed. The reconfigured dual H-bridge inverter can produce the same distribution of space voltage vectors with the conventional two-level inverters, but different switches are used to obtain these voltage vectors. A new seven-segment SVPWM strategy suppressing the deadtime effect of insulated gate bipolar transistors in the same leg is presented, and its algorithm and implementation are discussed. The proposed method is validated by simulations and experiments. [ABSTRACT FROM AUTHOR]