Impact of arbuscular mycorrhiza on the St. John’s wort (Hypericum perforatum) wilt disease induced by Colletotrichum cf. gloeosporioides

Journal of Plant Diseases and Protection - The importance of herbal plants is evident in the prevalent use as flavoring ingredients in food. However, meeting the growing demand for organic grown...     

Analysis of Mycosporine-Like Amino Acids in Selected Algae and Cyanobacteria by Hydrophilic Interaction Liquid Chromatography and a Novel MAA from the Red Alga Catenella repens

Mycosporine-like amino acids (MAAs), a group of small secondary metabolites found in algae, cyanobacteria, lichens and fungi, have become ecologically and pharmacologically relevant because of their pronounced UV-absorbing and photo-protective potential. Their analytical characterization is generally achieved by reversed phase HPLC and the compounds are often quantified based on molar extinction coefficients. As an alternative approach, in our study a fully validated hydrophilic interaction liquid chromatography (HILIC) method is presented. It enables the precise quantification of several analytes with adequate retention times in a single run, and can be coupled directly to MS. Excellent linear correlation coefficients (R² > 0.9991) were obtained, with limit of detection (LOD) values ranging from 0.16 to 0.43 µg/mL. Furthermore, the assay was found to be accurate (recovery rates from 89.8% to 104.1%) and precise (intra-day precision: 5.6%, inter-day precision ≤6.6%). Several algae were assayed for their content of known MAAs like porphyra-334, shinorine, and palythine. Liquid chromatography-mass spectrometry (LC-MS) data indicated a novel compound in some of them, which could be isolated from the marine species Catenella repens and structurally elucidated by nuclear magnetic resonance spectroscopy (NMR) as (E)-3-hydroxy-2-((5-hydroxy-5-(hydroxymethyl)-2-methoxy-3-((2-sulfoethyl)amino)cyclohex-2-en-1-ylidene)amino) propanoic acid, a novel MAA called catenelline.     

Constituents in evening primrose oil with radical scavenging,cyclooxygenase, and neutrophil elastase inhibitory activities

Cold-pressed, non-raffinated evening primrose oil was found to contain lipophilic radical scavengers. A highly enriched fraction of these compounds could be obtained from the oil by extraction with aqueous ethanol and subsequent liquid-liquid partitioning with petroleum. LC-DAD-MS analysis revealed that the fraction contained three aromatic compounds with identical UV and ESI-MS spectra. The compounds were isolated by RP-HPLC and their structures established by chemical and spectroscopic means as 3-O-trans-caffeoyl derivatives of betulinic, morolic, and oleanolic acid. The morolic acid derivative was a new compound. The three esters exhibited pronounced radical scavenging activity against the stable 2,2-diphenyl-1-picrylhydrazyl radical and were potent inhibitors of neutrophil elastase and cyclooxygenase-1 and -2 in vitro. Commercial samples of evening primrose oils contained only traces of these lipophilic antioxidants.     

Role of histone H3 lysine 27 methylation in X inactivation

The Polycomb group (PcG) protein Eed is implicated in regulation of imprinted X-chromosome inactivation in extraembryonic cells but not of random X inactivation in embryonic cells. The Drosophila homolog of the Eed-Ezh2 PcG protein complex achieves gene silencing through methylation of histone H3 on lysine 27 (H3-K27), which suggests a role for H3-K27 methylation in imprinted X inactivation. Here we demonstrate that transient recruitment of the Eed-Ezh2 complex to the inactive X chromosome (Xi) occurs during initiation of X inactivation in both extraembryonic and embryonic cells and is accompanied by H3-K27 methylation. Recruitment of the complex and methylation on the Xi depend on Xist RNA but are independent of its silencing function. Together, our results suggest a role for Eed-Ezh2-mediated H3-K27 methylation during initiation of both imprinted and random X inactivation and demonstrate that H3-K27 methylation is not sufficient for silencing of the Xi.     

The challenge of micropollutants in aquatic systems

The increasing worldwide contamination of freshwater systems with thousands of industrial and natural chemical compounds is one of the key environmental problems facing humanity. Although most of these compounds are present at low concentrations, many of them raise considerable toxicological concerns, particularly when present as components of complex mixtures. Here we review three scientific challenges in addressing water-quality problems caused by such micropollutants. First, tools to assess the impact of these pollutants on aquatic life and human health must be further developed and refined. Second, cost-effective and appropriate remediation and water-treatment technologies must be explored and implemented. Third, usage and disposal strategies, coupled with the search for environmentally more benign products and processes, should aim to minimize introduction of critical pollutants into the aquatic environment.     

Compression plating of radial and ulnar fractures in the goat.

Internal fixation of radial and ulnar fractures in three goats was accomplished using bone plates. Intervals between the time of fracture and internal fixation varied from one to 13 days. The goats were ambulatory the day after surgery, and recoveries were uneventful.