Effects of a selenium-enriched diet on antioxidant response in adult crayfish (Procambarus clarkii)

Many diets employed in aquaculture are enriched with selenium to improve the diet quality and its conservation. The aim of the study was to investigate the effects of a diet enriched in selenium (1.21 mg kg(-1)) on the antioxidant response of Procambarus clarkii (Girard, 1852). Crayfish fed a diet with lower selenium content (0.30 mg kg(-1)) were the control. Selenium accumulation, enzymatic activities, and total glutathione were evaluated in hepatopancreas of adults of both sexes fed with both diets for 50 days at two experimental times (T(30), T(50) days). Treated females exhibited the highest selenium bioaccumulation during both experimental times, while treated males displayed the highest selenium concentration after 30 days, compared to control crayfish. A sex-related difference was found for the response of the analyzed enzymes in the selenium diet-treated specimens. In fact, superoxide dismutase, glutathione peroxidase and glyoxalase I activities in males were more sensitive compared with females, showing depleted activities in both experimental times. Catalase activity was induced in females (T(50)), while glutathione S-transferase activity was the highest in treated females and the lowest in treated males, compared with own controls. Only glutathione reductase activity and glutathione content showed the same trend in both sexes, which were both lowered in treated specimens, when compared with control crayfish. This result might be due to the effect of selenium toxicity on this freshwater species. Males and females of P. clarkii showed a different susceptibility to the prooxidant effects in a Se-enriched diet.     

One-Component Spray Polyurethane Foam from Liquefied Pinewood Polyols: Pursuing Eco-Friendly Materials

The use of petroleum-derived products should be avoided regarding the principles of green and sustainable chemistry. The work reported herein, is aimed at the liquefaction of pine shavings for the production of an environmentally-friendly polyol suitable to be used in the formulations of sprayable polyurethane foams. The biopolyols were obtained in high yield and were used to replace those derived from fossil sources, to produce more “greener” polyurethane foams and therefore, less dependent on petroleum sources, since the polyol component was substituted by products resulting from biomass liquefaction. The partial and fully exchange of the polyols was accomplished, and the results compared with a reference foam. The foams were afterward, chemical, physical, morphological, and mechanically characterized. The complete replacement of polyether polyol and polyol polyester has presented some similar characteristics as that used as a reference, validating that the path chosen for the development of more sustainable materials is on the right track for the contribution to a cleaner world.     

Relationship between neuropsychological tests and driver's license renewal tests in Parkinson's disease

Objective: To determine whether the standard Spanish driving test (ASDE test) was able to identify patients with Parkinson's disease (PD) at risk of unsafe driving and to examine the relationship between the ASDE test and the Useful Field of View (UFOV) as well as with a battery of neuropsychological tests in drivers with PD.

Methods: Thirty-seven patients with PD and 33 controls matched by age and education level were included in an observational study. All participants were active drivers and patients with PD underwent study procedures after taking the medication in the “on” period. Subjects with a Mini-Mental State Examination (MMSE) score ≤ 24 were excluded. Neuropsychological tests (Repeatable Battery for Neuropsychological Status [RBANS], Trail Making Test [TMT-A and -B], and Block Design test), driving performance tests (ASDE Driver Test and UFOV), and daytime sleepiness (Epworth Sleepiness Scale) were assessed.

Results: The PD group performed significantly worse than healthy controls in the ASDE Motor Coordination tests. No significant differences were observed in anticipation speed, multiple reaction time, concentrated attention, and resistance to monotony. All participants successfully completed the UFOV tests. Statistically significant differences between patients with PD and controls were found in processing speed (UFOV1; P =.03) and more patients with PD were found in the categories of higher driving risk levels (P =.03). In addition, patients with PD showed worse scores than healthy controls in visuospatial capacities (Line Orientation), psychomotor speed (Coding and TMT-A), memory (List Recognition, Story Recall), and executive function (TMT-B). The driving tests (ASDE and UFOV) showed a low sensitivity and a high specificity but a higher percentage of patients in the PD group failed in multiple reaction time, concentrated attention, and resistance to monotony. In addition, 18.9% of patients with PD showed a cutoff of 4 for UFOV risk. In the discriminant analysis, Line Orientation (visuospatial/constructive domain) and Figure Recall (delayed memory) were found to be statistically significant with a rate of correct classification of unsafe drivers with PD of 78.2%. In addition, normal results on the Line Orientation item were associated with a 1.5 times higher probability of non-risky driving in the multivariate analysis.

Conclusions: At early stages of the disease, about 19% of patients with PD showed difficulties that may affect their driving capabilities. Line Orientation and Figure Recall are useful to alert clinicians to the risk of unsafe driving. For this reason, patients with PD should be evaluated for driving abilities more regularly to determine the extent of deficits that may influence driving performance.     

Physicochemical variations in atmospheric aerosols recorded at sea onboard the Atlantic–Mediterranean 2008 Scholar Ship cruise (Part II): Natural versus anthropogenic influences revealed by PM10 trace element geochemistry

The geochemistry of PM₁₀ filter samples collected at sea during the Scholar Ship Atlantic–Mediterranean 2008 research cruise reveals a constantly changing compositional mix of pollutants into the marine atmosphere. Source apportionment modelling using Positive Matrix Factorization identifies North African desert dust, sea spray, secondary inorganic aerosols, metalliferous carbon, and V–Ni-bearing combustion particles as the main PM₁₀ factors/sources. The least contaminated samples show an upper continental crust composition (UCC)-normalised geochemistry influenced by seawater chemistry, with marked depletions in Rb, Th and the lighter lanthanoid elements, whereas the arrival of desert dust intrusions imposes a more upper crustal signature enriched in “geological” elements such as Si, Al, Ti, Rb, Li and Sc. Superimposed on these natural background aerosol loadings are anthropogenic metal aerosols (e.g. Cu, Zn, Pb, V, and Mn) which allow identification of pollution sources such as fossil fuel combustion, biomass burning, metalliferous industries, and urban–industrial ports. A particularly sensitive tracer is La/Ce, which rises in response to contamination from coastal FCC oil refineries. The Scholar Ship database allows us to recognise seaborne pollution sourced from NW Africa, the Cape Verde and Canary islands, and European cities and industrial complexes, plumes which in extreme cases can produce a downwind deterioration in marine air quality comparable to that seen in many cities, and can persist hundreds of kilometres from land.     

Antioxidant response versus selenium accumulation in the liver and kidney of the Siberian sturgeon (Acipenser baeri)

The aim of this study was to examine the effects of selenium on concentrations of metabolites and enzyme activities acting as antioxidant markers in liver and kidney of Siberian sturgeon Acipenser baeri. Sturgeons were fed selenium cysteine for 30 and 60 d at 1.25, 5, 20 mg Se kg⁻¹. Selenium level in the control feed was 0.32 mg kg⁻¹. Se concentration was measured in liver, kidney and muscle of every specimen. Sturgeon accumulated Se in tissues with a clear dose-response relationship and the highest Se concentration was recorded in liver. This outcome is lined up with the findings obtained on the antioxidant markers evaluated in both tissues, and in which a dose-response for several biomarkers was recorded in liver. The superoxide dismutase activity in Se-treated fish was generally induced, while catalase activity was lower in liver or unaltered in kidney. The concentrations of glutathione S-transferase, glutathione reductase and total glutathione responded differently for both tissues and were induced in a different way at both endpoints. No changes of glyoxalase I activity were noted for both Se-treated tissues, while for glyoxalase II enzyme in liver a dose-related pattern was found showing a reversible effect (decreased and increased counteractive response) only in the 5 mg kg⁻¹ group. Moreover, the highest Se concentrations did not cause marked changes in malondialdehyde levels of liver and kidney. The enhancement of glutathione peroxidase activity in Se-treated sturgeon might have prevented the lipid peroxidation in both tissues, providing to the Siberian sturgeon a great defense ability versus the prooxidant effect of selenium.