5-Fluoro-4-thiouridine phosphoramidite: new synthon for introducing photoaffinity label into oligodeoxynucleotides

The synthesis of phosphoramidite of 5-fluoro-4-thio-2'-O-methyluridine is described. An appropriate set of protecting groups was optimized including the 4-thio function introduced via 4-triazolyl as the 4-(2-cyanoethyl)thio derivative, and the t-butyldimethyl silyl for 2' and 3' hydroxyl protection, enabling efficient synthesis of the phosphoramidite. These protecting groups prevented unwanted side reactions during oligonucleotide synthesis. The utility of the proposed synthetic route was proven by the preparation of several oligonucleotides via automated synthesis. Photochemical experiments confirmed the utility of the synthon.     

Ergosterol and Fusarium mycotoxins content in two maize cultivars under different forms of nitrogen fertilizers

Mycotoxins are secondary metabolites produced by many filamentous fungi, such as Fusarium, and are widespread in nature and can adversely affect almost all organisms. Mycotoxins can be formed in very different conditions such as when plants are growing or in crops that are stored in improper conditions. One of the methods to prevent the formation of mycotoxins in powdered feed is using varieties of appropriate quality and proper mineral fertilization, primarily nitrogen. In this study, the concentration of ergosterol and mycotoxins in the kernels of two maize cultivars from different maturity groups in Poland during the harvest of 2011 and 2012 was investigated using HPLC methods. We aimed to analyse the concentration of ergosterol as a fungal biomass indicator and mycotoxins from two maize cultivars under six different forms of nitrogen fertilizers. The “stay‐green” hybrid ES Paroli was characterized by a significantly lower ergosterol and the ability to accumulate the mycotoxins, compared to the classic cultivar ES Palazzo. The varieties of maize that remain green for a longer time period, the so‐called stay‐green type, are characterized by a different coefficient of nitrogen remobilization compared to the classic hybrids. Their dynamics of growth and accumulation of nutrients indicates a nitrogen fertilization system, indicating that slow‐release fertilizers are potentially more adapted to the cycles of maize vegetation. Hence, compared to the classic variant, the “stay‐green” variety uses nitrogen more effectively from mineral fertilizers. Such hybrids are healthier and remain in good condition for a longer time; therefore, they are characterized by a lower pathogen pressure. Thus, the cultivation of such varieties can be considered as one of the elements of integrated maize production. We observed identical reactions of the studied experimental factors for both vegetation seasons, which indicates the lack of environmental impact on the functioning and interaction of experimental factors.     

Quantifying and imaging NY-ESO-1/LAGE-1-derived epitopes on tumor cells using high affinity T cell receptors

Presentation of intracellular tumor-associated Ags (TAAs) in the context of HLA class I molecules offers unique cancer-specific cell surface markers for the identification and targeting of tumor cells. For most peptide Ags, the levels of and variations in cell surface presentation remain unknown, yet these parameters are of crucial importance when considering specific TAAs as targets for anticancer therapy. Here we use a soluble TCR with picomolar affinity for the HLA-A2-restricted 157-165 epitope of the NY-ESO-1 and LAGE-1 TAAs to investigate presentation of this immunodominant epitope on the surface of a variety of cancer cells. By single molecule fluorescence microscopy, we directly visualize HLA-peptide presentation for the first time, demonstrating that NY-ESO-1/LAGE-1-positive tumor cells present 10-50 NY-ESO-1/LAGE-1(157-165) epitopes per cell.     

RedMDStream: Parameterization and Simulation Toolbox for Coarse-Grained Molecular Dynamics Models

Coarse-grained (CG) models in molecular dynamics (MD) are powerful tools to simulate the dynamics of large biomolecular systems on micro- to millisecond timescales. However, the CG model, potential energy terms, and parameters are typically not transferable between different molecules and problems. So parameterizing CG force fields, which is both tedious and time-consuming, is often necessary. We present RedMDStream, a software for developing, testing, and simulating biomolecules with CG MD models. Development includes an automatic procedure for the optimization of potential energy parameters based on metaheuristic methods. As an example we describe the parameterization of a simple CG MD model of an RNA hairpin.     

High-pressure liquid-solid chromatography of the ecdysones--insect molting hormones

A rapid, high-pressure liquid-solid Chromatographie technique was developed for the separation, detection and analysis of ecdy-steroids. The advantages in using this system for the identification of ecdysteroids in combination with NMR and mass spectrometry and its potential application in analyzing material from biological and synthetic, systems are presented.     

Extracts and Steroids from the Edible Mushroom Hypholoma lateritium Exhibit Anti‐Inflammatory Properties by Inhibition of COX‐2 and Activation of Nrf2

Hypholoma lateritium is an edible macrofungus with a common distribution in Europe, North America, and the Far East. The aim of this study was to investigate the potential anti‐inflammatory effects of H. lateritium extracts and its isolated steroids: fasciculic acid B, fasciculol E, fasciculol C, lanosta‐7,9(11)‐diene‐12β,21α‐epoxy‐2α,3β,24β,25‐tetraol, fasciculol F, and demethylincisterol A2. Organic (hexane, chloroform and 50 % methanol) and water extracts of H. lateritium were subjected to in vitro assays to determine pro‐inflammatory protein levels, such as cyclooxygenase‐2 (COX‐2), cytosolic prostaglandin E2 synthase (cPGES), and antioxidant nuclear factor (erythroid‐derived 2)‐like 2 (Nrf2). Fungal extracts demonstrated significant activities on pro‐inflammatory protein levels with minor differences among the activities of the fractions of different polarities. All the compounds proved to exert notable inhibitory properties on COX‐2 and were capable to stimulate the Nrf2 pathway. Fungal extracts and the compounds exerted no cytotoxic activities on RAW 264.7 cells.     

Does operational sex ratio influence relative strength of purging selection in males versus females?

According to theory, sexual selection in males may efficiently purge mutation load of sexual populations, reducing or fully compensating ‘the cost of males’. For this to occur, mutations not only need to be deleterious to both sexes, they also must affect males more than females. A frequently overlooked problem is that relative strength of selection on males versus females may vary between environments, with social conditions being particularly likely to affect selection in males and females differently. Here, we induced mutations in red flour beetles (Tribolium castaneum) and tested their effect in both sexes under three different operational sex ratios (1:2, 1:1 and 2:1). Induced mutations decreased fitness of both males and females, but their effect was not stronger in males. Surprisingly, operational sex ratio did not affect selection against deleterious mutations nor its relative strength in the sexes. Thus, our results show no support for the role of sexual selection in the evolutionary maintenance of sex.     

In a comfort zone and beyond—Ecological plasticity of key marine mediators

Copepods of the genus Calanus are the key components of zooplankton. Understanding their response to a changing climate is crucial to predict the functioning of future warmer high‐latitude ecosystems. Although specific Calanus species are morphologically very similar, they have different life strategies and roles in ecosystems. In this study, C. finmarchicus and C. glacialis were thoroughly studied with regard to their plasticity in morphology and ecology both in their preferred original water mass (Atlantic vs. Arctic side of the Polar Front) and in suboptimal conditions (due to, e.g., temperature, turbidity, and competition in Hornsund fjord). Our observations show that “at the same place and time,” both species can reach different sizes, take on different pigmentation, be in different states of population development, utilize different reproductive versus lipid accumulation strategies, and thrive on different foods. Size was proven to be a very mutable morphological trait, especially with regard to reduced length of C. glacialis. Both species exhibited pronounced red pigmentation when inhabiting their preferred water mass. In other domains, C. finmarchicus individuals tended to be paler than C. glacialis individuals. Gonad maturation and population development indicated mixed reproductive strategies, although a surprisingly similar population age structure of the two co‐occurring species in the fjord was observed. Lipid accumulation was high and not species‐specific, and its variability was due to diet differences of the populations. According to the stable isotope composition, both species had a more herbivorous diatom‐based diet in their original water masses. While the diet of C. glacialis was rather consistent among the domains studied, C. finmarchicus exhibited much higher variability in its feeding history (based on lipid composition). Our results show that the plasticity of both Calanus species is indeed impressive and may be regulated differently, depending on whether they live in their “comfort zone” or beyond it.