Molecular cloning and antibacterial activity of hepcidin from Chinese rare minnow (Gobiocypris rarus)

AbstractBackgroundHepcidins, a kind of cysteine-rich antimicrobial peptides, play important roles in host immunological processes and iron regulation, which have been identified from several fish species. The rare minnow (Gobiocypris rarus), an endemic cyprinid fish in China, has been used extensively as model animal in laboratory. However, little is known about its hepcidin. Here, we report the cloning and characterization of a hepcidin gene from the liver of Chinese rare minnow.ResultsThe full-length cDNA of rare minnow hepcidin is 662bp, which contains an ORF of 273bp encoding a prepropeptide of 90 amino acid residues. The predicted prepropeptide contains three domains: a signal peptide of 24 amino acids, a prodomain of 41 amino acids, and a mature peptide of 25 amino acids. Sequence alignment showed eight conserved cysteine residues in the mature peptide, which formed four disulfide bonds in spatial structure. The deduced structure of mature peptide showed a high degree of homology to the human hepcidin. Phylogenetic analysis showed that it had a close relationship with zebrafish hepcidin, and clustered in a clade with these from Cyprinidae. Synthetic peptide of rare minnow hepcidin could inhibit the growth of Gram positive bacterium Staphylococcus aureus and Gram negative bacteria Escherichia coli and Aeromonas hydrophila.ConclusionThese results suggested that rare minnow hepcidin had typical structure of hepcidins and antibacterial activity. It could participate in innate immune response as an antibacterial agent and be used as antibiotic substance

Effect of Gamma Irradiation on Microcrystalline Structure of Phragmites Cellulose

Effect of 60Co-γ irradiation treatment on cellulose structure originating from Phragmites communis trim (PCT) was investigated on the basis of irradiation doses of 0 to 2000 kGy at a dose rate of 2 kGy h-1. Scanning electron micrograph images showed that surface morphologies of PCT cellulose could become fragmented after being treated with 60Co-γ irradiation. Based on X-ray diffraction profiles, crystallinity and amorphous region of microcrystalline cellulose treated by irradiation were obviously changed. Fourier transform IR spectroscopy data indicated that a new characteristic peak corresponding to carbonyl (1734 cm -1) appeared after PCT cellulose was treated with 60Co-γ irradiation, which suggested that PCT cellulose was degraded after irradiation treatment

Decoupled advection-dispersion method for determining wall thickness of slurry trench cutoff walls

Low-permeability slurry trench cutoff walls are commonly constructed as barriers for containment of subsurface point-source pollution or as part of seepage-control systems on contaminated sites. A method to estimate wall thickness in slurry wall design is proposed based on decoupling the advective and dispersive components of contaminant fluxes through the wall. The relative error of the result obtained by the proposed method compared with that by an analytical solution was found to increase as the ratio of the specified breakthrough exit concentration (c*) to the source concentration (c0) increased. For c*/c0 of less than 0.1, which covers common practical situations, the relative error was not greater than 4% and was always conservative, indicating that the proposed method provides sufficient accuracy for design. For a given breakthrough criterion (i.e., c*/c0), the relative error was low for the scenarios having either a low or high column Peclet number, where either dispersion or advection dominates the contaminant migration, respectively, and the relative error was high for the scenario having an intermediate column Peclet number, in which case the coupling effect of advective and dispersive migrations is relatively high

Deadline Constrained Cloud Computing Resources Scheduling through an Ant Colony System Approach

Cloud computing resources scheduling is essential for executing workflows in the cloud platform because it relates to both execution time and execution cost. In this paper, we adopt a model that optimizes the execution cost while meeting deadline constraints. In solving this problem, we propose an Improved Ant Colony System (IACS) approach featuring two novel strategies. Firstly, a dynamic heuristic strategy is used to calculate a heuristic value during an evolutionary process by taking the workflow topological structure into consideration. Secondly, a double search strategy is used to initialize the pheromone and calculate the heuristic value according to the execution time at the beginning and to initialize the pheromone and calculate heuristic value according to the execution cost after a feasible solution is found. Therefore, the proposed IACS is adaptive to the search environment and to different objectives. We have conducted extensive experiments based on workflows with different scales and different cloud resources. We compare the result with a particle swarm optimization (PSO) approach and a dynamic objective genetic algorithm (DOGA) approach. Experimental results show that IACS is able to find better solutions with a lower cost than both PSO and DOGA do on various scheduling scales and deadline conditions

Clinical application of the paraspinal erector approach for spinal canal decompression in upper lumber burst fractures

OBJECTIVE: Percutaneous pedicle screw fixation is commonly used for upper lumber burst fractures. The direct decompression remains challenging with this minimally invasive surgery. The objective was to evaluate a novel paraspinal erector approach for effective and direct decompression in patients with canal compromise and neurologic deficit. METHOD: Patients (n = 21) with neurological deficiency and Denis B type upper lumbar burst fracture were enrolled in the study, including 14 cases in the L1 and 7 cases in the L2. The patients underwent removal of bone fragments from the spinal canal through intervertebral foramen followed by short-segment fixation. Evaluations included surgery-related, such as duration of surgery and blood loss, and 12-month follow-up, such as the kyphotic angle, the height ratio of the anterior edge of the vertebra, the ratio of sagittal canal compromise, visual analog scale (VAS), Oswestry Disability Index (ODI), and Frankel scores. RESULTS: All patients achieved direct spinal canal decompression using the paraspinal erector approach followed by percutaneous pedicle screw fixation. The mean operation time (SD) was 173 (23) min, and the mean (SD) blood loss was 301 (104) ml. Significant improvement was noted in the kyphotic angle, 26.2 ± 8.7 prior to operation versus 9.1 ± 4.7 at 12 months after operation (p <0.05); the height ratio of the anterior edge of the injured vertebra, 60 ± 16% versus 84 ± 9% (p <0.05); and the ratio of sagittal canal compromise, 46.5 ± 11.4% versus 4.3 ± 3.6% (p <0.05). Significant improvements in VAS (7.3 ± 1.2 vs. 1.9 ± 0.7, p <0.05), ODI (86.7 ± 5.8 vs. 16.7 ± 5.1, p <0.05), and Frankel scores were also noted. CONCLUSIONS: The paraspinal erector approach was effective for direct spinal canal decompression with minimal injury in the paraspinal muscles or spine. Significant improvements in spinal function and prognostics were achieved after the percutaneous pedicle screw fixation

Epileptiform discharge upregulates p-ERK1/2, growth-associated protein 43 and synaptophysin in cultured rat hippocampal neurons

AbstractExtracellular signal-regulated protein kinase, ERK1/2 is activated by phosphorylation (p-ERK1/2) during environmental stress such as epileptiform discharge. We investigated the role of ERK1/2 in abnormal axon growth and synapse reorganization in cultured neurons displaying epileptiform activity.The cultured neurons displaying epileptiform activity were treated with magnesium-free extracellular fluid for 3h and monitored epileptiform discharges using whole-cell patch clamp. Two study groups, neurons displaying epileptiform activity and the same neurons treated with ERK1/2 inhibitor U0126, were studied at six time points, 0min, 30min, 2h, 6h, 12h, and 24h following discharge. The expressions of p-ERK1/2, C-fos, growth-associated protein 43 (GAP-43) and synaptophysin (SYP), as markers of axon growth and synapse reorganization, were investigated by double-label immunofluorescence and western blotting.In the neurons displaying epileptiform activity, p-ERK1/2 was detected immediately following discharge, and expression peaked at 30min. The expression of C-fos, GAP-43 and SYP followed the same pattern as p-ERK1/2. In the treated group, p-ERK1/2 was inhibited completely, and C-fos, GAP-43 and SYP were reduced.These findings indicate that epileptiform discharge activates ERK1/2 which regulates C-fos in cultured neurons displaying epileptiform activity, and this cascade may upregulate GAP-43 and SYP to contribute to axon growth and synapse reorganization to potentiate epileptic activities