Post-thaw addition of seminal plasma reduces tyrosine phosphorylation on the surface of cryopreserved equine sperm, but does not reduce lipid peroxidation

The objective was to verify the relationship between equine semen cryopreservation and changes related to increased lipid peroxidation. Also, addition of autologous or homologous seminal plasma from a stallion with a good freezing response to post-thawed sperm was tested to determine whether it would confer protection. Frozen-thawed sperm were evaluated and allocated into three groups: without plasma addition, and supplemented with either homologous or autologous seminal plasma. All groups were evaluated at 0, 60 and 120 min after incubation at 37 °C. Cryopreservation did not increase plasma membrane disorders (mean ± SEM 9.48 ± 0.65 and 1.62 ± 0.23% in raw and frozen-thawed sperm, respectively). However, both membrane peroxidation and protein phosphorylation were increased (P < 0.05) compared to raw semen (1.74 and 5.20-fold, respectively). There was a correlation (r = 0.73; P < 0.05) between the increase in lipid peroxidation and tyrosine phosphorylation. Seminal plasma, regardless of origin, reduced (P > 0.05) tyrosine phosphorylation present on the surface of cryopreserved sperm; however, lipid peroxidation was not significantly reduced. In conclusion, we inferred that emergence of phosphorylated proteins on the surface of cryopreserved sperm was due to increased lipid peroxidation that occurred during the freezing/thawing process; however, reduced tyrosine phosphorylation that occurred after addition of seminal plasma was triggered by other mechanisms, apparently independent from the reduction in membrane peroxidation.     

Species loss of stoneflies (Plecoptera) in the Czech Republic during the 20th century

1. Rapid expansion and intensification of anthropogenic activities in the 20th century has caused profound changes in freshwater assemblages. Unfortunately, knowledge of the extent and causes of species loss (SL) is limited due to the lack of reliable historical data. An unusual data set allows us to compare changes in the most sensitive of aquatic insect orders, the Plecoptera, at some 170 locations in the Czech Republic between two time periods, 1955–1960 and 2006–2010. Historical data (1890–1911) on assemblages of six lowland rivers allow us to infer even earlier changes. 2. Regional stonefly diversity decreased in the first half of the 20th century. Streams at lower altitudes lost a substantial number of species, which were never recovered. In the second half of the century, large‐scale anthropogenic pressure caused SL in all habitats, leading to a dissimilarity of contemporary and previous assemblages. The greatest changes were found at sites affected by organic pollution and a mixture of organic pollution and channelisation or impoundment. Colonisation of new habitats was observed in only three of the 80 species evaluated. 3. Species of moderate habitat specialisation and tolerance to organic pollution were most likely to be lost. Those with narrow specialisations in protected habitats were present in both historical and contemporary collections. 4. Contemporary assemblages are the consequence of more than a 100 years of anthropogenic impacts. In particular, streams at lower altitude and draining intensively exploited landscapes host a mere fragment of the original species complement. Most stonefly species are less frequently present than before, although their assemblages remain almost intact in near‐natural mountain streams. Our analyses demonstrate dramatic restriction of species ranges and, in some cases, apparent changes in altitudinal preference throughout the area.     

Effects of phytoremediation and application of organic amendment on the mobility of heavy metals in a polluted soil profile

This research aims to assess the effect of the application of biosolids compost and phytoremediation on the mobility of total and biodisponibles (DTPA) fractions of cadmium, copper, lead, and zinc from different horizons of a superficially contaminated soil. Leaching experiment in soil columns was proposed. Treatments contemplated application of compost biosolid and phytoremediation. Two destructive samplings were performed. Total and DTPA trace metals were identified in each horizon. The overall performance of the various elements in its total and DTPA forms show greater concentration in horizon A and fewer gradients between horizons Bt and BC, thus assuming that the high content of clay in horizon Bt (62.9%) limits its movement through the horizons. In the mobile nutrients, a greater mobility was evidenced in DTPA fractions if compared to Total fractions. In the horizon A, the more mobile metals, such as Zn and Cd, evidenced a greater percentage of DTPA/Total fractions in all treatments. The application of compost with or without plant diminished the mobilization of Zn, Cu, and Cd Total, thus limiting a potential leaching to inferior horizons. However, this effect was not observed in the DTPA fraction.     

Ultrastructural detection of an unusual intranuclear bacterium in Pentastiridius leporinus (Hemiptera: Cixiidae)

Pentastiridius leporinus is an important vector of sugar beet pathogens in eastern France. An electron microscope survey on the insect-associated microflora revealed the occurrence of intranuclear prokaryotic cells in every internal organ analysed. These bacteria, which could also be found in the cytoplasm surrounding the nucleus, had a homogeneous coccoid (ca. 0.45 microm) or rod (0.45-1 microm) shape. The presence of three membrane layers was observed, the outermost forming a kind of vacuole containing generally a single microorganism. No cytopathological abnormalities were detected in the infected cells. To our knowledge, this is the first report of a hemipteran species infected by intranuclear bacteria. The possible identity of this microorganism is discussed.     

First case of highly pathogenic H5N1 avian influenza virus in Spain

Background  

In August 2006 a major epidemic of bluetongue virus serotype 8 (BTV8) started off in North-West Europe. In the course of 2007 it became evident that BTV8 had survived the winter in North-West Europe, re-emerged and spread exponentially. Recently, the European Union decided to start vaccination against BTV8. In order to improve the understanding of the epidemiological situation, it was necessary to execute a cross-sectional serological study at the end of the BT vector season. Cattle were the target species for cross-sectional serological studies in Europe at the end of 2006 and 2007. However, there was no information on the BTV8-seroprevalence in sheep and goats.     

DNA conformation in N,N-dimethyl formamide-H2O solutions

Optical density, viscosity, and light scattering measurements for calf thymus DNA in water–N,N dimethyl formamide (DMF) solutions are presented. DMF content varied between 0 and 60% (v/v) and DNA molecular weight varied between 15 × 10⁶ and 0.5 × 10⁶. Complementary measurements of the solubility of adenine, thymine, guanine, and cytosine in H₂O–DMF mixtures are presented. The denaturation temperature of DNA, manifested by about a 35% increase of optical density, is gradually depressed by increasing DMF content. However, a significant increase of OD occurs even before (and even after) the denaturation point, when DMF content is increased isothermally. The intrinsic viscosity also exhibits a large decrease when DMF content is increased both before and after the denaturation point. Light scattering data for high-molecular-weight DNA in the predenaturation range indicate a decrease of the mean-square radius and a constant molecular weight on increasing DMF content. The results, interpreted in terms of the wormlike chain of Kratky and Porod, indicate a large decrease of the persistence length of DNA. For low-molecular-weight DNA, radius and molecular weight increase with DMF content, indicating intermolecular aggregation. The formation of compact structures of native DNA is discussed in terms of an increased solubility of uncharged bases, and a decreased solubility of phosphate and deoxyribose groups, when a less polar environment is provided by the addition of DMF.     

Regulatory roles of miR-155 and let-7b on the expression of inflammation-related genes in THP-1 cells: effects of fatty acids

The main aim of this investigation was to study the regulatory roles of let-7b and miR-155-3p on the expression of inflammation-associated genes in monocytes, macrophages, and lipopolysaccharide (LPS)-activated macrophages (AcM). A second goal was to analyze the potential modulatory roles of different fatty acids, including oleic, palmitic, eicosapentaenoic (EPA), and docosahexaenoic (DHA), on the expression of these miRNAs in the three cell types. This hypothesis was tested in human acute monocytic leukemia cells (THP-1), which were differentiated into macrophages with 2-O-tetradecanoylphorbol-13-acetate (TPA) and further activated with LPS for 24 h. Monocytes, macrophages, and AcM were transfected with a negative control, or mimics for miR-155-3p and miR-let-7b-5p. The expression of both miRNAs and some proinflammatory genes was analyzed by qRT-PCR. Interestingly, let-7b mimic reduced the expression of IL6 and TNF in monocytes, and SERPINE1 expression in LPS-activated macrophages. However, IL6, TNF, and SERPINE1 were upregulated in macrophages by let-7b mimic. IL6 expression was higher in the three types of cells after transfecting with miR-155-3p mimic. Similarly, expression of SERPINE1 was increased by miR-155-3p mimic in monocytes and macrophages. However, TLR4 was downregulated by miR-155-3p in monocytes and macrophages. Regarding the effects of the different fatty acids, oleic acid increased the expression of let-7b in macrophages and AcM and also increased the expression of miR-155 in monocytes when compared with DHA but not when compared with non-treated cells. Overall, these results suggest anti- and proinflammatory roles of let-7b and miR-155-3p in THP-1 cells, respectively, although these outcomes are strongly dependent on the cell type. Noteworthy, oleic acid might exert beneficial anti-inflammatory effects in immune cells (i.e., non-activated and LPS-activated macrophages) by upregulating the expression of let-7b.     

LINE-1 and inflammatory gene methylation levels are early biomarkers of metabolic changes: association with adiposity

We analyzed whether global and inflammatory genes methylation can be early predictors of metabolic changes and their associations with the diet, in a cross-sectional study (n?=?40). Higher global methylation was associated to adiposity, insulin resistance, and lower quality of the diet. Methylation of IL-6, SERPINE1 and CRP genes was related to adiposity traits and macronutrients intake. SERPINE1 hypermethylation was also related to some metabolic alterations. CRP methylation was a better predictor of insulin resistance than CRP plasma concentrations. Global and inflammatory gene promoter hypermethylation can be good early biomarkers of adiposity and metabolic changes and are associated to the quality of the diet.