Leaf dehydroascorbate reductase and catalase activity is associated with soil drought tolerance in bread wheat

A number of morphological, physiological and phenological traits have been suggested as significant markers of adaptation to drought in bread wheat (Triticum aestivum L.). This study was aimed at the identification of a relationship between dehydroascorbate reductase (DHAR, EC 1.8.5.1) and catalase (CAT, EC 1.11.1.6) activities in leaves of wheat plants and stability of yield components under water deficit. The single chromosome substitution lines of cv. Chinese Spring carrying separate chromosomes from the donor Synthetic 6x, an artificial hexaploid combining the genomes of the two wild species, Triticum dicoccoides (AABB) and Aegilops tauschii (DD), were the objects of the investigations. The activities of the DHAR and CAT were correlated with flag leaf relative water content and two indexes of stability of grain yield components under drought across the set substitution lines. The lines carrying a synthetic hexaploid homologous pair of chromosomes 1B, 1D, 2D, 3D or 4D all expressed a low constitutive level of DHAR and the lines carrying chromosomes 3B, 1D, 2D and 3D a low constitutive level of CAT. All were able to increase this level (by fourfold for DHAR and by 1.5-fold for CAT) in response to stress caused by water deficit. When challenged by drought stress, these lines tended to be the most effective in retaining the water status of the leaves and preventing the grain yield components from being compromised. The discovered genetic variability for enzymes activity in leaves of wheat might be a useful selection criterion for drought tolerance.     

The combined GnRH-agonist and intrauterine levonorgestrel-releasing system treatment of complicated atypical hyperplasia and endometrial cancer: a pilot study

In this article, we present the results of organ-preserving treatment applied in 24 patients of reproductive age with atypical endometrial hyperplasia or early-stage endometrial cancer. All of them would like to preserve their reproductive potential. Thirteen women with atypical endometrial hyperplasia were treated with the combination of six intramuscular injections of 3.75 mg gonadotropin-releasing hormone agonist (GnRHa)--leuproreline acetate depot every 4 weeks. After the third injection of 3.75 mg of leuproreline acetate, the levonorgestrel intrauterine hormonal system containing 52 mg levonorgestrel (Mirena(?), Bayer, Germany) was inserted for at least 6 months. In 11 women with stage IA well-differentiated endometrial adenocarcinoma, hormonal therapy included nine intramuscular injections of 3.75 mg of GnRHa every 4 weeks. After the third injection of 3.75 mg of GnRHa, we also inserted a GnRH-IUS (Mirena(?)) for at least 12 months. This type of therapy was effective for all these patients and may be offered to be used as an alternative to surgery in women with atypical endometrial hyperplasia or early stage 1A well-differentiated endometrial cancer in women of reproductive age. Three women with endometrial cancer became pregnant and two of them delivered at term and one has an ongoing pregnancy.     

Characterization of conserved viral leader RNA sequences that stimulate innate immunity through TLRs

Viruses of the order Mononegavirales encompass life-threatening pathogens with single-stranded segmented or nonsegmented negative-strand RNA genomes. The RNA genomes are characterized by highly conserved sequences at the extreme untranslated 3' and 5' termini that are most important for virus infection and viral RNA synthetic processes. The 3' terminal genome regions of negative-strand viruses such as vesicular stomatitis virus, Sendai virus, or influenza virus contain a high number of conserved U and G nucleotides, and synthetic oligoribonucleotides encoding such sequences stimulate sequence-dependent cytokine responses via TLR7 and TLR8. Immune cells responding to such sequences include NK cells, NK/T cells, plasmacytoid, and myeloid dendritic cells, as well as monocytes and B cells. Strong Th1 and pro-inflammatory cytokine responses are also induced upon in vivo application of oligoribonucleotides. It appears possible that the presence of highly conserved untranslated terminal regions in the viral genome fulfilling fundamental functions for the viral replication may enable the host to induce directed innate immune defense mechanisms, by allowing pathogen detection through essential RNA regions that the virus cannot readily mutate.     

High-throughput sequencing of the mitochondrial genomes from archived fish scales: an example of the endangered putative species flock of Sevan trout <Emphasis Type="Italic">Salmo ischchan</Emphasis>

Burrowing benthic animals belonging to the same functional group may produce species-specific effects on microbially mediated nitrogen (N) processes depending upon different ecological traits. We investigated the effects of two tube-dwelling organisms, amphipods (Corophium insidiosum) and chironomid larvae (Chironomus plumosus), on benthic N cycling in bioturbated estuarine sediments. Aims of this work were to analyze the interactions among burrowers and N-related microbial processes in two distinct sedimentary environments colonized by benthic animals with different ecological traits. We hypothesized higher rates of nitrification and higher coupled nitrification–denitrification in sediments with C. insidiosum due to continuous ventilation rates. We expected higher denitrification of water column nitrate in sediments with C. plumosus due to lower and intermittent ventilation activity and lower oxygen levels in burrows. To this purpose, we combined process–specific (nitrification and denitrification) with net N flux measurements in intact and reconstructed sediments. Sediments with C. insidiosum had higher rates of oxygen demand and of potential nitrification and higher concentration of pore water NH₄⁺ as compared to sediments with C. plumosus. Sediments with both species displayed comparable net N₂ fluxes, mostly sustained by respiration of water column NO₃^? in sediments with chironomid larvae and by NO₃^? produced within sediments in sediments with corophiid amphipods. Corophium insidiosum stimulated nitrification nearly 15-fold more as compared to C. plumosus. Overall, our results demonstrate that sediments with burrowing fauna may display similar rates of denitrification, but underlying mechanisms may deeply vary and be species-specific.     

BioVyon Protein A, an alternative solid-phase affinity matrix for chromatin immunoprecipitation

Chromatin immunoprecipitation (ChIP) is an important technique in the study of DNA/protein interactions. The ChIP procedure, however, has limitations in that it is lengthy, can be inconsistent, and is prone to nonspecific binding of DNA and proteins to the bead-based solid-phase matrices that are often used for the immunoprecipitation step. In this investigation, we examined the utility of a new matrix for ChIP assays, BioVyon Protein A, a solid support based on porous polyethylene. In ChIP experiments carried out using two antibodies and seven DNA loci, the performance of BioVyon Protein A was significantly better, with a greater percentage of DNA pull-down in all of the assays tested compared with bead-based matrices, Protein A Sepharose, and Dynabeads Protein A. Furthermore, the rigid porous disc format within a column made the BioVyon matrix much easier to use with fewer steps and less equipment requirements, resulting in a significant reduction in the time taken to process the ChIP samples. In summary, BioVyon Protein A provides a column-based assay method for ChIP and other immunoprecipitation-based procedures; the rigid porous structure of BioVyon enables a fast and robust protocol with higher ChIP enrichment ratios.     

Sources and donors of resistance to wheat spot blotch caused by Bipolaris sorokiniana Shoem. (Cochliobolus sativus Drechs. ex Dastur)

The resistance of wheat lines and cultivars from the Institute of Crop Breeding (Harbin, China) and synthetic, hexaploid wheat lines derived from T. durum and T. tauschii (CIMMYT) were screened for resistance to spot blotch Bipolaris sorokiniana Shoem. using field and laboratory tests. The highly and moderately resistant wheat samples were determined. The satisfactory coincidence of data obtained from evaluation of type reaction of seedlings and disease severity in adult plant stage was demonstrated. The genetics of resistance in Chinese lines Long 98-4554, Long 98-4546, Long mai 24, Long mai 23 and Canadian line 181-5 was studied using hybridological analysis. The resistance in these lines was inherited as quantitative traits and was conditioned by a few (one or two) genes. The absence of susceptible plants in F₂ in crosses of resistant lines Long 98-4554, Long 98-4546, Long mai 24 and 181-5 can testify to the presence of a common gene of resistance. Our data reveals the poor genetic diversity for spot blotch resistance in studying wheat genotypes.     

Autofluorescence Imaging of Living Pancreatic Islets Reveals Fibroblast Growth Factor-21 (FGF21)-Induced Metabolism

Fibroblast growth factor-21 (FGF21) has therapeutic potential for metabolic syndrome due to positive effects on fatty acid metabolism in liver and white adipose tissue. FGF21 also improves pancreatic islet survival in excess palmitate; however, much less is known about FGF21-induced metabolism in this tissue. We first confirmed FGF21-dependent activity in islets by identifying expression of the cognate coreceptor Klothoβ, and by measuring a ligand-stimulated decrease in acetyl-CoA carboxylase expression. To further reveal the effect of FGF21 on metabolism, we employed a unique combination of two-photon and confocal autofluorescence imaging of the NAD(P)H and mitochondrial NADH responses while holding living islets stationary in a microfluidic device. These responses were further correlated to mitochondrial membrane potential and insulin secretion. Glucose-stimulated responses were relatively unchanged by FGF21. In contrast, responses to glucose in the presence of palmitate were significantly reduced compared to controls showing diminished NAD(P)H, mitochondrial NADH, mitochondrial membrane potential, and insulin secretion. Consistent with the glucose-stimulated responses being smaller due to continued fatty acid oxidation, mitochondrial membrane potential was increased in FGF21-treated islets by using the fatty acid transport inhibitor etomoxir. Citrate-stimulated NADPH responses were also significantly larger in FGF21-treated islets suggesting preference for citrate cycling rather than acetyl-CoA carboxylase-dependent fatty acid synthesis. Overall, these data show a reduction in palmitate-induced potentiation of glucose-stimulated metabolism and insulin secretion in FGF21-treated islets, and establish the use of autofluorescence imaging and microfluidic devices to investigate cell metabolism in a limited amount of living tissue.     

Antioxidative-related enzyme activity in Alyssum markgrafii shoot cultures as affected by nickel level

Shoot cultures of rare Balkan hyperaccumulating species Alyssum markgrafii were subjected to high nickel concentrations of 1, 3, 5, and 8?mM. The effects of graded nickel concentrations on toxicity, pigments, and several components of plant antioxidative defense system were characterized. Toxic effects of excess nickel were observed through slower growth and biomass decrease, together with increased reactive oxygen species (ROS) production and lipid peroxidation. Nickel exposure decreased chlorophyll a, b, total chlorophyll as well as carotenoid concentration. Addition of sodium benzoate, potent ROS scavenger, showed concentration-dependent disturbing effect on nickel hyperaccumulation, lowering the content of accumulated nickel in A. markgrafii shoots. General reducing power represented by low molecular weight antioxidants and phenols was inversely correlated with nickel concentration. Among the investigated antioxidative enzymes, POD seems to play important role in ROS level regulation upon excessive nickel in medium.     

Triethanolammonium acetate as a multifunctional ionic liquid in the palladium-catalyzed green Heck reaction

An efficient green Heck reaction protocol was performed using a triethanolammonium acetate ionic liquid–palladium(II) catalytic system. The ionic liquid used acts as a reaction medium, base, precatalyst-precursor, and mobile support for the active Pd species. Our experimental investigation indicates that performing the Heck reaction in ionic liquid is superior to the same procedure carried out in triethanolamine. The mechanism of the reaction of triethanolammonium acetate with PdCl₂ was examined using density functional theory (M06 method). It was found that two Pd(II) complexes are formed, one of which acts further as a precatalyst yielding catalytically active Pd(0) complex. The calculated activation energies are in agreement with our experimental findings.