The effects of the neurotoxic agent emamectin benzoate on the expression of immune and stress-related genes and blood serum profiles in the Rainbow trout

Molecular Biology Reports - Emamectin, a neurotoxic agent, is a semi-synthetic insecticide that belongs to the Avermectin family and is used against helmintic infections in the Salmonidae family....     

Selected anthropometric variables and aerobic fitness as predictors of cardiovascular disease risk in children

The aim of this study was to assess the suitability of body mass index, waist circumference, waist-to-height ratio and aerobic fitness as predictors of cardiovascular risk factor clustering in children. A cross-sectional study was conducted with 290 school boys and girls from 6 to 10 years old, randomly selected. Blood was collected after a 12-hour fasting period. Blood pressure, waist circumference (WC), height and weight were evaluated according to international standards. Aerobic fitness (AF) was assessed by the 20-metre shuttle-run test. Clustering was considered when three of these factors were present: high systolic or diastolic blood pressure, high low-density lipoprotein (LDL) cholesterol, high triglycerides, high plasma glucose, high insulin concentrations and low high-density lipoprotein (HDL) cholesterol. A ROC curve identified the cut-off points of body mass index (BMI), WC, waist-to-height ratio (WHtR) and AF as predictors of risk factor clustering. BMI, WC and WHR resulted in significant areas under the ROC curves, which was not observed for AF. The anthropometric variables were good predictors of cardiovascular risk factor clustering in both sexes, whereas aerobic fitness should not be used to identify cardiovascular risk factor clustering in these children.     

Gut microbiota in wild and captive Guizhou snub‐nosed monkeys,Rhinopithecus brelichi

Many colobine species—including the endangered Guizhou snub‐nosed monkey (Rhinopithecus brelichi) are difficult to maintain in captivity and frequently exhibit gastrointestinal (GI) problems. GI problems are commonly linked to alterations in the gut microbiota, which lead us to examine the gut microbial communities of wild and captive R. brelichi. We used high‐throughput sequencing of the 16S rRNA gene to compare the gut microbiota of wild (N = 7) and captive (N = 8) R. brelichi. Wild monkeys exhibited increased gut microbial diversity based on the Chao1 but not Shannon diversity metric and greater relative abundances of bacteria in the Lachnospiraceae and Ruminococcaceae families. Microbes in these families digest complex plant materials and produce butyrate, a short chain fatty acid critical to colonocyte health. Captive monkeys had greater relative abundances of Prevotella and Bacteroides species, which degrade simple sugars and carbohydrates, like those present in fruits and cornmeal, two staples of the captive R. brelichi diet. Captive monkeys also had a greater abundance of Akkermansia species, a microbe that can thrive in the face of host malnutrition. Taken together, these findings suggest that poor health in captive R. brelichi may be linked to diet and an altered gut microbiota.     

Selenium accumulation in durum wheat and spring canola as a function of amending soils with selenite, selenate and or sulphate

Aims

A comparison was performed between plant species to determine if extractable, rather than total soil Se, is more effective at predicting plant Se accumulation over a full growing season.

Methods

Durum wheat (Triticum turgidum L.) and spring canola (Brassica napus L.) were sown in potted soil amended with 0, 0.1, 1.0, or 5.0 mg kg^?1 Se as SeO₄ ^2? or SeO₃ ^2?. In addition, SeO₄ ^2?-amended soils were amended with 0 or 50 mg kg^?1 S as SO₄ ^2?. Soils were analyzed for extractable and total concentration of Se ([Se]). Twice during the growing season plants were harvested and tissue [Se] was determined.

Results

Plants exposed to SeO₃ ^2? accumulated the least Se. Fitted predictive models for whole plant accumulation based on extractable soil [Se] were similar to models based on total [Se] in soil (R²?=?0.73 or 0.74, respectively) and selenium speciation and soil [S] were important soil parameters to consider. As well, soil S amendments limited Se toxicity.

Conclusions

Soil quality guidelines (SQGs) based on extractable Se should be considered for risk assessment, particularly when Se speciation is unknown. Predictive models to estimate plant Se uptake should include soil S, a modifier of Se accumulation.     

Production of Serine Proteases by the Oyster Pathogen Perkinsus marinus (Apicomplexa) In Vitro

ABSTRACT. Analysis of the cell-free supernatants of Perkinsus marinus cultures by sodium dodecylsulfate-polyacrylamide gel electrophoresis (SDS-PAGE) and silver staining revealed the presence of as many as 17 bands ranging in molecular weight from 239 to 32 kDa. These bands were not present in un-inoculated medium. Moreover, P. marinus produces extracellular proteins that possess proteolytic activities; the cell-free supernatants of P. marinus cultures could digest a variety of proteins including gelatin, casein, fibronectin and laminin. Oyster plasma was also digested by cell-free culture supernatants. The proteolytic activity in cell-free culture supernatants was detected 24 h post-inoculation, while no proteolytic activity could be detected in cell lysates. The proteolytic activities were characterized using substrate-impregnated sodium dodecylsulfate-polyacrylamide gels and had approximate molecular weights ranging from 55 to 35 kDa. The proteolytic activity of cell-free culture supernatants was inhibited by the serine protease inhibitors phenylmethylsulphonyl fluoride, 3,4-dichloroisocoumarin and soybean trypsin inhibitor. In contrast, inhibitors (i.e. trans-epoxysuccinyll-leucylamido(4-guanidino)-butane, 1, 10-phenanthroline, captopril, ethylenediaminetetracetic acid, pepstatin A or diazoacetyl-DL-norleucine methyl ester) from the other three classes of proteases had no effect. It was concluded that the P. marinus proteases in cell-free culture supernatants are serine proteases.     

Genetic analysis of the Escherichia coli FtsZ.ZipA interaction in the yeast two-hybrid system. Characterization of FtsZ residues essential for the interactions with ZipA and with FtsA

The recruitment of ZipA to the septum by FtsZ is an early, essential step in cell division in Escherichia coli. We have used polymerase chain reaction-mediated random mutagenesis in the yeast two-hybrid system to analyze this interaction and have identified residues within a highly conserved sequence at the C terminus of FtsZ as the ZipA binding site. A search for suppressors of a mutation that causes a loss of interaction (ftsZ(D373G)) identified eight different changes at two residues within this sequence. In vitro, wild type FtsZ interacted with ZipA with a high affinity in an enzyme-linked immunosorbent assay, whereas FtsZ(D373G) failed to interact. Two mutant proteins examined restored this interaction significantly. In vivo, the alleles tested are significantly more toxic than the wild type ftsZ and cannot complement a deletion. We have shown that a fusion, which encodes the last 70 residues of FtsZ in the two-hybrid system, is sufficient for the interaction with FtsA and ZipA. However, when the wild type sequence is compared with one that encodes FtsZ(D373G), no interaction was seen with either protein. Mutations surrounding Asp-373 differentially affected the interactions of FtsZ with ZipA and FtsA, indicating that these proteins bind the C terminus of FtsZ differently.