Evaluation of bioeffects of a long-term administering ChangLe on rat by proton NMR method and biochemical examination

High resolution H-1 nuclear magnetic resonance ( NMR) spectroscopy has been employed to assess long-term toxicological effects of ChangLe (a kind of rare earth complex applied in agriculture). Male Wistar rats were administrated orally with ChangLe at doses of 0, 0.1, 0.2, 2.0, 10 and 20 mg/kg body weight daily, respectively, for 6 months. Urine was collected at-day 30, 60, go and serum samples were taken after 6 months. Many low-molecular weight metabolites were identified by H-1 NMR spectra of rat urine. A decrease in citrate and an increase in ketone bodies, creatinine, DMA, DMG, TMAO, and taurine in the urine of the rats. receiving high doses were found by H-1 NMR spectra. These may mean that high-dosage of ChangLe impairs the specific region of liver and kidney, such as renal tubule and mitochondria. The decrease in citrate and the increase in succinate and alpha-ketoglutarate were attributed to a combination of the inhibition of certain citric acid enzymes, renal tubular acidosis and the abnormal fatty acid catabolism. The information of the renal capillary necrosis could be derived from the increase in DMIA, DMG and TMAO. The increase in taurine was due to hepatic mitochondria dysfunction. The conclusions were supported by the results of biochemical measure. merits and enzymatic assay.

Identification, Characterization, and Molecular Application of a Virulence-Associated Autotransporter from a Pathogenic Pseudomonas fluorescens Strain

A gene, pfa1, encoding an autotransporter was cloned from a pathogenic Pseudomonas fluorescens strain, TSS, isolated from diseased fish. The expression of pfa1 is enhanced during infection and is regulated by growth phase and growth conditions. Mutation of pfa1 significantly attenuates the overall bacterial virulence of TSS and impairs the abilities of TSS in biofilm production, interaction with host cells, modulation of host immune responses, and dissemination in host blood. The putative protein encoded by pfa1 is 1,242 amino acids in length and characterized by the presence of three functional domains that are typical for autotransporters. The passenger domain of PfaI contains a putative serine protease (Pap) that exhibits apparent proteolytic activity when expressed in and purified from Escherichia coli as a recombinant protein. Consistent with the important role played by PfaI in bacterial virulence, purified recombinant Pap has a profound cytotoxic effect on cultured fish cells. Enzymatic analysis showed that recombinant Pap is relatively heat stable and has an optimal temperature and pH of 50 degrees C and pH 8.0. The domains of PfaI that are essential to autotransporting activity were localized, and on the basis of this, a PfaI-based autodisplay system (named AT1) was engineered to facilitate the insertion and transport of heterologous proteins. When expressed in E. coli, AT1 was able to deliver an integrated Edwardsiella tarda immunogen (Et18) onto the surface of bacterial cells. Compared to purified recombinant Et18, Et18 displayed by E. coli via AT1 induced significantly enhanced immunoprotection.

叠前地震数据规则化、重建及噪音压制

I address of reconstruction of spatial irregular sampling seismic data to regular grids. Spatial irregular sampling data impairs results of prestack migration, multiple attenuations, spectra estimation. Prestack 5-D volumes are often divided into sub-sections for further processing. Shot gathers are easy to obtain from irregular sampling volumes. My strategy for reconstruction is as follows: I resort irregular sampling gathers into a form of easy to bin and perform bin regularization, then utilize F-K inversion to reconstruct seismic data. In consideration of poor ability of F-K regularization to fill in large gaps, I sort regular sampling gathers to CMP and proposed high-resolution parabolic Radon transform to interpolate data and extrapolate offsets. To strong interfering noise--multiples, I use hybrid-domain high-resolution parabolic Radon transform to attenuate it. F-K regularization demand ultimately for lower computing costs. I proposed several methods to further improve efficiency of F-K inversion: first I introduce 1D and 2D NFFT algorithm for a rapid calculation of DFT operators; then develop fast 1D and 2D CG method to solve least-square equations, and utilize preconditioner to accelerate convergence of CG iterations; what’s more, I use Delaunay triangulation for weight calculation and use bandlimit frequency and varying bandwidth technique for competitive computation. Numerical 2D and 3D examples are offered to verify reasonable results and more efficiency. F-K regularization has poor ability to fill in large gaps, so I rearrange data as CMP gathers and develop hybrid-domain high-resolution parabolic Radon transforms which be used ether to interpolate null traces and extrapolate near and far offsets or suppress a strong interfere noise: multiples. I use it to attenuate multiples to verify performances of our algorithm and proposed routines for industrial application. Numerical examples and field data examples show a nice performance of our method.