Antioxidant properties of trans-epsilon-viniferin as compared to stilbene derivatives in aqueous and nonaqueous media

trans-Epsilon-viniferin, the dimer of resveratrol, extracted from Vitis vinifera, has been evaluated for its antioxidant capacity. Its properties have been compared to those of resveratrol and synthetic stilbenic derivatives (4-hydroxystilbene, 4,4'-dihydroxystilbene, 3,5-dihydroxystilbene, and trimethylresveratrol), in regard to their liposolubility using two media with different polarity. The bleaching of beta-carotene by lipoperoxyl (LOO.) radicals in an oil/water (O/W) emulsion and the scavenging of superoxide anions (O(-)(2) in dimethyl sulfoxide (DMSO) using 5,5-dimethyl-1-pyrroline-N-oxide as a spin trap were followed using UV-visible and electron paramagnetic resonance, respectively. Epsilon-viniferin exhibits the best antioxidant capacity in the DMSO/O(-)(2) polar system (IC(50) = 0.14 mM) while 4,4'-dihydroxystilbene presents the highest antioxidant capacity in the O/W/LOO. system (inhibition of beta-carotene bleaching, 82%). Partition coefficients and kinetics of partition between 1-octanol and water were measured to discuss the antioxidant efficiency of the compounds in relation with their chemical structure.     

Effects of oxygen tension in the gas atmosphere during in vitro maturation, in vitro fertilization and in vitro culture on the efficiency of in vitro production of mouse embryos

Effects of oxygen (O2) tension in the gas atmosphere during in vitro maturation (IVM), in vitro fertilization (IVF) and in vitro culture (IVC) on the efficiency of in vitro production of mouse embryos were examined. Mouse oocytes recovered from large antral follicles were subjected to IVM in Waymouth medium for 15, 16 and 17 hr under 5 or 20% O2 and then subjected to IVF and IVC under 5 or 20% O2 tension. Lowering the O2 tension in the gas atmosphere for IVM from 20 to 5% improved the cleavage rate after IVF when the oocytes were subjected to IVM for 15 hr; however, no improvement in the cleavage rate was observed when the culture period for IVM was extended to 16 and 17 hr. Lowering the O2 tension to 5% for IVM and IVC improved the development of the cleaved oocytes to the blastocyst stage, regardless of the culture period for IVM. However, the O2 tension for IVF had no remarkable effect on the subsequent embryonic development. These results demonstrate that 5% O2 is superior to 20% O2 for IVM and IVC, and suggest that 20% O2 for IVM may delay oocyte maturation and/or the acquisition of fertilizability and impair the developmental competence of oocytes.     

Cattle vaccination against Q fever in the rural district of Bratislava]

Cattle attendants on two farms in the Outer Bratislava district showed symptoms of Q-fever. The blood of the cows in these farms was found to contain antibodies to Coxiella burnetti and the causative agent of the disease was detected in milk samples of aborting cows by biological assays on hamsters (Mesocricetus auratus). The naturally invaded dairy cows with antibodies in the blood and heifers without antibodies were vaccinated with different doses of inactivated suspension of C. burnetii in stage I. A different antibody reaction to vaccination was obtained after the application of a four-fold amount of vaccine. It was proved that the animals did not excrete the causative agent of the infection even after administration of lower doses of the vaccine on the 120th day after vaccination.     

Nitrogen metabolism and seed composition as influenced by glyphosate application in glyphosate-resistant soybean

Previous research has demonstrated that glyphosate can affect nitrogen fixation or nitrogen assimilation in soybean. This 2-year field study investigated the effects of glyphosate application of 1.12 and 3.36 kg of ae ha(-1) on nitrogen metabolism and seed composition in glyphosate-resistant (GR) soybean. There was no effect of glyphosate application on nitrogen fixation as measured by acetylene reduction assay, soybean yield, or seed nitrogen content. However, there were significant effects of glyphosate application on nitrogen assimilation, as measured by in vivo nitrate reductase activity (NRA) in leaves, roots, and nodules, especially at high rate. Transiently lower leaf nitrogen or (15)N natural abundance in high glyphosate application soybean supports the inhibition of NRA. With the higher glyphosate application level protein was significantly higher (10.3%) in treated soybean compared to untreated soybean. Inversely, total oil and linolenic acid were lowest at the high glyphosate application rate, but oleic acid was greatest (22%) in treated soybean. These results suggest that nitrate assimilation in GR soybean was more affected than nitrogen fixation by glyphosate application and that glyphosate application may alter nitrogen and carbon metabolism.     

Grass greenness flush can influence breeding phenology and fertility in equatorial thoroughbred mares in the absence of photoperiod variation

Reproductive phenology is an important trait subjected to natural selection. Current horses in America belong to the Palearctic original populations after being introduced by European colonizers. Photoperiod variation is the main environmental factor for the adjustment of reproductive timing in horses, but is absent in equatorial areas. Here we hypothesize that seasonality of green‐grass availability may influence breeding phenology in equatorial regions. We used data of 929 services to mares from 2006 to 2011 in a thoroughbred equine exploitation in Ecuador that experienced strong grass seasonality. Actual births could not be used to infer natural phenology because they were influenced by management decisions. Instead, we used variations in the probability of pregnancy after a service as a measure of the natural tendency of mares to show breeding phenology. We found that although managers tended to schedule pregnancies in two periods within the year, mares were more prone to become pregnant after the increase in grass greenness that takes place at the beginning of the year (February). Our finding has potential applications to improve the success of services and the welfare of animals, by providing green‐grass stimuli in the appropriate season.     

Algal and Cyanobacterial Lectins and Their Antimicrobial Properties

Lectins are proteins with a remarkably high affinity and specificity for carbohydrates. Many organisms naturally produce them, including animals, plants, fungi, protists, bacteria, archaea, and viruses. The present report focuses on lectins produced by marine or freshwater organisms, in particular algae and cyanobacteria. We explore their structure, function, classification, and antimicrobial properties. Furthermore, we look at the expression of lectins in heterologous systems and the current research on the preclinical and clinical evaluation of these fascinating molecules. The further development of these molecules might positively impact human health, particularly the prevention or treatment of diseases caused by pathogens such as human immunodeficiency virus, influenza, and severe acute respiratory coronaviruses, among others.     

Hydrological parameterization of piping in loess‐rich soils in the Bergisches Land,Nordrhein‐Westfalen,Germany

Pedohydrological properties were investigated on a piped slope in the Bergisches Land in the Rhenish Slate Mountains (Nordrhein‐Westfalen, Germany). The study confirmed that genesis and development of pipes decisively depend on hydrological conditions in the soils. Vertical water permeability of saturated samples was very high. This promoted fast seepage. Many macropores produced by earthworms also caused high transport capacity for soil water. Even more efficient were the burrows of moles and mice, enabling immediate infiltration and direct vertical and lateral water movement. On the contrary, the horizontal saturated permeability was low indicating no correlation with piping. Porosity of piped soils was not different to that of other soils of the region without pipes.     

Performance of ratio‐based,soil‐adjusted and atmospherically corrected multispectral vegetation indices in predicting herbaceous aboveground biomass in a Colophospermum mopane tree–shrub savanna

Accurate and near‐real‐time estimation of herbaceous aboveground biomass (AGB) at farm level is crucial for monitoring pasture production and proactive management of stock in semiarid rangelands. Despite its importance, remote sensing has been rarely used by range ecologists and managers in Zimbabwe. This study aimed at assessing the performance of classical multispectral vegetation indices (MVIs) when either singly regressed with measured herbaceous AGB or combined with other visible spectral bands in predicting herbaceous AGB in a Colophospermum mopane savannah. Field herbaceous AGB and corresponding Landsat 8 Operational Land Imager visible spectral data were collected during the 2016–2017 rainy season. Relationships between measured AGB and classical MVIs and extended models of MVIs combined with other visible bands were analysed using bootstrapped simple and stepwise multiple linear regression functions. When MVIs were singly regressed with measured AGB, ratio‐based indices yielded the highest r² value of 0.64, followed by soil‐adjusted indices (r² = 0.61), while atmospherically corrected MVIs showed the lowest r² of 0.58 (p = 0.00). A significant improvement in herbaceous AGB estimation was obtained using a combination of MVIs and other visible bands. Soil‐adjusted MVIs showed the greatest increase (44–46%) in r², while atmospherically corrected and ratio‐based MVIs poorly improved (<5%). The findings demonstrate that combining MVIs with Landsat 8 optical bands, especially green band, provides the best models for estimating AGB in C. mopane savanna rangelands. These findings emphasize the importance of testing band‐MVI combinations when developing models for estimating herbaceous AGB.