Analysis of Structures, Functions, and Epitopes of Aminopeptidase from Trichinella spiralis

We have previously reported that the recombinant T. spiralis aminopeptidase (rTsAP) could induce a partial protective immunity against T. spiralis infection in mice. The aim of this study was to predict the structures and functions of TsAP protein by using the full length cDNA sequence of TsAP gene. TsAP sequence was 1515 bp length with a 1515 bp biggest ORF encoding 504-amino acid protein. The molecular weight and isoelectric point of TsAP were 54.7 kDa and 6.69, respectively. TsAP structure domains contained a Peptidase_M17_N and a Peptidase_M17 domain, which has the function of catalysis of the hydrolysis of N-terminal amino acid residues. TsAP had no signal peptide site and transmembrane domain, and located in cytoplasm. The secondary structure of TsAP contained 16 α-helix, 14 β-strand and 29 coils. The TsAP had 11 and 21 potential antigenic epitopes of T cell and B cell, respectively. Based on the phylogenetic analyses of TsAP, T. spiralis have the closest relationship with Plasmodium falciparum. TsAP was a kind of proteolytic enzyme with a variety of biological functions and its antigenic epitopes could provide important insights on the diagnostic antigens and target molecular of anti-Trichinella drugs

Distribution and diversity of coliform bacteria in estuary of jiahe river, china

Waterborne outbreaks of pathogenic bacteria from contaminated water are serious threats for public health. Coliform bacteria have been regarded as one of the most important indicators for monitoring pathogenic bacteria. To address potential pathogenic bacterial outbreaks, the distribution and diversity of coliform bacteria in Jiahe river, which flows through densely-populated urban area in China, were detected. Escherichia Coli and other coliform bacteria were counted using the membrane filter technique to describe the distribution of the coliform bacteria. Phylogenetic analysis was applied to investigate the diversity of the coliform bacteria. The results suggested that the quantities of coliform bacteria varied greatly between five sampling sites with the highest value at site YT4 and the lowest value at site YT2. Highest concentrations of E. coli and other coliform bacteria were also observed at YT4, while the lowest value was detected at sites YT3 and YT2, respectively. Various coliform bacteria were classified by phylogenetic analysis, including Citrobacter, Klebsiella, Enterobacter, and Raoultella. Components of coliform bacteria affiliated into these four genera were various in all sampling sites. The statistical analysis suggested that the distribution of coliform bacteria were remarkably influenced by total bacteria amount. Multiple environmental parameters were proved to affect the diversity of coliform bacteria. The results of this study revealed the correlation between coliform bacteria and the environmental parameters, which is important for predicting and preventing waterborne transmission of pathogenic bacteria

14,15-Epoxyeicosatrienoic acid induces the proliferation and anti-apoptosis of human carcinoma cell

Epoxyeicosatrienoic acids [EETs], which are cytochrome P450 epoxygenase metabolites of arachidonic acid, have anti-inflammatory effects, modulate smooth muscle proliferation, and inhibit smooth muscle migration. This study was designed to determine whether exogenous EETs have any effect on the cell proliferation and apoptosis of carcinoma cell as well as the possible signaling pathways of EETs in this regulation. The effects of EETs on the proliferation and anti-apoptosis of human carcinoma cells were measured by MTT assay and flowcytometric analysis, and the regulation of PPARy, epithelial growth factor receptor [EGFR], extracellular signal-regulated kinase [ERK], phosphatidylinositol 3 [PI3]-Kinase/AKT pathways was investigated by reverse transcriptase polymerase chain reaction [RT-PCR] and western blot analysis. Results of this study suggested that 14, 15-EET may activate the expression of PPARy in Tea-8113 cells. 14,15-EET may stimulate cell proliferation, and increase the percentage of cells during S-G2-M phase in Tea-8113 cells significantly. The levels of EGFR, ERK, and PI3 kinase/AKT proteins were significantly induced by treatment of 14, 15-EET and 14,15-EET/ AUDA, but no significant changes were observed by addition of GW9662. These findings suggest that exogenous 14,15-EET has potent inhibitory effect on proliferation, and could induce apoptosis in Tea-8113 cell, and these changes are related to the expression of PPARganna, the activation of EGFR, ERK, and PI3 kinase/AKT proteins

Performance of Kriging and EWPM for relative air pollution exposure risk assessment

This study investigates the effectiveness of the Kriging interpolation model and the Emission Weighted Proximity Model [EWPM] in assessing relative exposure risk of air pollution using results from the American Meteorological Society/EPA Regulatory Model [AERMOD] as benchmarks. We used simulated exposure risk to SO[2] in the Dallas area in Texas in this evaluation. Results suggest that the relative exposure risks to SO[2] at different locations in the study area as estimated by EWMP are closer to estimated risks from AERMOD when compared with the results calculated by Kriging. In addition, study results also indicate that the relative exposure risks calculated by Kriging are similar to those from AERMOD when the density of emission sources in the area in question is high. It is therefore concluded that relative exposure risks determined by both the Kriging interpolation method and the EWPM are acceptable when it is not possible to use AERMOD. In situations when the density of emission sources is low in the study area. EWPM is a better choice than Kriging

Study on the transport of sediment oxygen demand-related organic matter in bottom sediment system

Approach of organic material anaerobic biodegradation and species of organic matter in sediment are discussed, and then a classifying method of the species is proposed on a new viewpoint. The pore water sediment oxygen demand [SOD] numerical model in bottom sediment system is proposed originally, which differs from other advection-dispersion-sorption [ADS] model in adding a SOD-creating term. The model was preliminarily validated via pilot experiment. Finally, this model was used to simulate SOD concentration of pore water in bottom sediment, and the sensitivity of parameters in the model was analyzed. The results indicate that SOD-creating factor at beginning stage and pore water SOD-attenuating factor in bottom sediment are the most important coefficients in the new model and should be estimated accurately. Because of the assumption of equilibrium of sorption/desorption, the new model appears to be valid only with less than 5 m/d vertical velocity of pore water