Functional identification of Arabidopsis ATSIP2 (At3g57520) as an alkaline α-galactosidase with a substrate specificity for raffinose and an apparent sink-specific expression patter

Arabidopsis ATSIP2 has recently been suggested to be a raffinose synthase gene. However, it has high amino acid identity to functionally characterized alkaline α-galactosidases from Cucumis melo and Zea mays. Using the Sf9 insect cell expression system, we demonstrate that recombinant ATSIP2 is a genuine alkaline α-galactosidase with a distinct substrate specificity for raffinose, and not a raffinose synthase. A β-glucuronidase reporter construct using the ATSIP2 promoter shows that ATSIP2 is strongly expressed in sink tissues of Arabidopsis, i.e. sink leaves and non-xylem parts of the root stele, suggesting a physiological function in raffinose phloem unloading

Hardy's inequality for functions vanishing on a part of the boundary

We develop a geometric framework for Hardy's inequality on a bounded domain when the functions do vanish only on a closed portion of the boundary.Comment: 26 pages, 2 figures, includes several improvements in Sections 6-8 allowing to relax the assumptions in the main results. Final version published at http://link.springer.com/article/10.1007%2Fs11118-015-9463-

Dimethoxyflavone isolated from the stem bark of Stereospermum kunthianum possesses antidiarrhoeal activity in rodents

This study was undertaken to evaluate the antidiarrhoeal activity of 3, 7, 4/-trihydroxy-3/-(8//-acetoxy-7//-methyloctyl)-5, 6-dimethoxyflavone, a flavonoid isolated from the stem bark of Stereospermum kunthianum. The antidiarrhoeal activity was evaluated using rodent models with diarrhoea. The normal intestinal transit, castor oil-induced intestinal transit and castor oilinduced diarrhoea tests in mice as well as castor oil-induced intestinal fluid accumulation in rats were employed in the study. The animals were pretreated with distilled water (10 ml/kg for mice, 5 ml/kg for rats), dimethoxyflavone (25 mg/kg or 50 mg/kg), morphine (10 mg/kg), or indomethacin (10 mg/kg) before induction of diarrhoea with castor oil (0.2ml for mice and 2ml for rats). Dimethoxyflavone dose dependently and significantly reduced (P<0.05) castor oil-induced intestinal motility. Its antimotility effect at the dose of 50 mg/kg was higher compared to that of morphine (10 mg/kg). Dimethoxyflavone (25 mg/kg and 50 mg/kg)caused a delay in the onset of diarrhoea reduction in the number and weight of wet stools and total stools in mice with castor oilinduced diarrhoea compared to the distilled water treated mice. Treatment with dimethoxyflavone (25 mg/kg or 50 mg/kg) did not produce any remarkable effect on castor oil-induced intestinal fluid accumulation in rats and normal intestinal transit in mice. The results indicate that dimethoxyflavone possesses antidiarrhoeal activity due to its intestinal antimotility effect and inhibition of other diarrhoeal pathophysiological processes. In conclusion, dimethoxyflavone reduced the frequency and severity of diarrhoea in the diarrhoeal models studied.Keywords: Dimethoxyflavone, Stereospermum kunthianum, flavonoid, antidiarrhoeal activit

Worker remittances and the global preconditions of ‘smart development’

With the growing environmental crisis affecting our globe, ideas to weigh economic or social progress by the ‘energy input’ necessary to achieve it are increasingly gaining acceptance. This question is intriguing and is being dealt with by a growing number of studies, focusing on the environmental price of human progress. Even more intriguing, however, is the question of which factors of social organization contribute to a responsible use of the resources of our planet to achieve a given social result (‘smart development’). In this essay, we present the first systematic study on how migration – or rather, more concretely, received worker remittances per GDP – helps the nations of our globe to enjoy social and economic progress at a relatively small environmental price. We look at the effects of migration on the balance sheets of societal accounting, based on the ‘ecological price’ of the combined performance of democracy, economic growth, gender equality, human development, research and development, and social cohesion. Feminism in power, economic freedom, population density, the UNDP education index as well as the receipt of worker remittances all significantly contribute towards a ‘smart overall development’, while high military expenditures and a high world economic openness are a bottleneck for ‘smart overall development’

Red wine and components flavonoids inhibit UGT2B17 in vitro

Background The metabolism and excretion of the anabolic steroid testosterone occurs by glucuronidation to the conjugate testosterone glucuronide which is then excreted in urine. Alterations in UGT glucuronidation enzyme activity could alter the rate of testosterone excretion and thus its bioavailability. The aim of this study is to investigate if red wine, a common dietary substance, has an inhibitory effect on UGT2B17. Methods Testosterone glucuronidation was assayed using human UGT2B17 supersomes with quantification of unglucuronidated testosterone over time using HPLC with DAD detection. The selected red wine was analysed using HPLC and the inhibitory effects of the wine and phenolic components were tested independently in a screening assay. Further analyses were conducted for the strongest inhibitors at physiologically relevant concentrations. Control experiments were conducted to determine the effects of the ethanol on UGT2B17. Results Over the concentration range of 2 to 8% the red wine sample inhibited the glucuronidation of testosterone by up to 70% over 2 hours. The ethanol content had no significant effect. Three red wine phenolics, identified by HLPC analyses, also inhibited the enzyme by varying amounts in the order of quercetin (72%), caffeic acid (22%) and gallic acid (9%); using a ratio of phenolic:testosterone of 1:2.5. In contrast p-coumaric acid and chlorogenic acid had no effect on the UGT2B17. The most active phenolic was selected for a detailed study at physiologically relevant concentrations, and quercetin maintained inhibitory activity of 20% at 2 M despite a ten-fold excess of testosterone. Conclusion This study reports that in an in vitro supersome-based assay, the key steroid-metabolising enzyme UGT2B17 is inhibited by a number of phenolic dietary substances and therefore may reduce the rate of testosterone glucuronidation in vivo. These results highlight the potential interactions of a number of common dietary compounds on testosterone metabolism. Considering the variety of foodstuffs that contain flavonoids, it is feasible that diet can elevate levels of circulating testosterone through reduction in urinary excretion. These results warrant further investigation and extension to a human trial to delineate the healt

What Goes in Must Come out: Testing for Biases in Molecular Analysis of Arbuscular Mycorrhizal Fungal Communities

Arbuscular mycorrhizal (AM) fungi are widely distributed microbes that form obligate symbioses with the majority of terrestrial plants, altering nutrient transfers between soils and plants, thereby profoundly affecting plant growth and ecosystem properties. Molecular methods are commonly used in the study of AM fungal communities. However, the biases associated with PCR amplification of these organisms and their ability to be utilized quantitatively has never been fully tested. We used Terminal Restriction Fragment Length Polymorphism (TRFLP) analysis to characterise artificial community templates containing known quantities of defined AM fungal genotypes. This was compared to a parallel in silico analysis that predicted the results of this experiment in the absence of bias. The data suggest that when used quantitatively the TRFLP protocol tested is a powerful, repeatable method for AM fungal community analysis. However, we suggest some limitations to its use for population-level analyses. We found no evidence of PCR bias, supporting the quantitative use of other PCR-based methods for the study of AM fungi such as next generation amplicon sequencing. This finding greatly improves our confidence in methods that quantitatively examine AM fungal communities, providing a greater understanding of the ecology of these important fungi

Fundamental workings of chemical substitution at the A-site of perovskite oxides— a 207Pb NMR study of Ba-substituted PbZrO3

Funding: This work was supported by the Hessian State Ministry for Higher Education, Research and the Arts under the LOEWE collaborative project FLAME (Fermi level engineering of anti-ferroelectric materials for energy storage and insulation systems). B. M. acknowledges the financial support by the Slovenian Research Agency (core funding P2-0105). G. B. acknowledges the financial support by the German Research Foundation under the contract Bu-911/28-1. P. G. acknowledges the financial support by the Dutch Research Council (NWO) for the ECCM Tenure Track funding under the project number ECCM.006.Lead zirconate (PbZrO3, PZ) is a prototype antiferroelectric (AFE) oxide from which state-of-the-art energy storage materials are derived by chemical substitutions. A thorough understanding of the structure–property relationships of PZ-based materials is essential for both performance improvement and the design of more environmentally friendly replacements. (Pb1−xBax)ZrO3 (PBZ) can serve as a model system for studying the effect of A-site substitution in the perovskite lattice, with barium destabilizing the AFE state. Here, the two-dimensional 207Pb solid-state NMR spectra of PZ and PBZ were recorded to analyze the local structural role of barium substitution. At low substitution levels, 207Pb NMR spectroscopy reveals the presence of Pb–O bond length disorder. Upon crossing the threshold value of x for the macroscopic phase transition into a ferroelectric (FE) state, the barium cations cause local-scale lattice expansions in their vicinity, resulting in the collapse of two lead lattice sites into one. The stabilization of the larger volume site coincides with the favoring of larger lead displacements. We also observed more covalent bonding environments which may originate from the lower polarizability of the barium cations, facilitating the formation of stronger Pb–O bonds in their vicinity. From the local structural point of view, we propose that the substitution-induced AFE → FE phase transition is therefore related to an increasing correlation of larger lead displacements in larger oxygen cavities as the barium content increases. Our results also highlight 207Pb NMR spectroscopy as a valuable method for the characterization of the structure–property relationships of PbZrO3-based AFE and FE oxides.Peer reviewe

DIMETHOXYFLAVONE ISOLATED FROM THE STEM BARK OF STEREOSPERMUM KUNTHIANUM POSSESSES ANTIDIARRHOEAL ACTIVITY IN RODENTS

This study was undertaken to evaluate the antidiarrhoeal activity of 3, 7, 4/-trihydroxy-3/-(8//-acetoxy-7//-methyloctyl)-5, 6-dimethoxyflavone, a flavonoid isolated from the stem bark of Stereospermum kunthianum. The antidiarrhoeal activity was evaluated using rodent models with diarrhoea. The normal intestinal transit, castor oil-induced intestinal transit and castor oil-induced diarrhoea tests in mice as well as castor oil-induced intestinal fluid accumulation in rats were employed in the study. The animals were pretreated with distilled water (10 ml/kg for mice, 5 ml/kg for rats), dimethoxyflavone (25 mg/kg or 50 mg/kg), morphine (10 mg/kg), or indomethacin (10 mg/kg) before induction of diarrhoea with castor oil (0.2ml for mice and 2ml for rats). Dimethoxyflavone dose dependently and significantly reduced (

On the way to large-scale and high-resolution brain-chip interfacing

Brain-chip-interfaces (BCHIs) are hybrid entities where chips and nerve cells establish a close physical interaction allowing the transfer of information in one or both directions. Typical examples are represented by multi-site-recording chips interfaced to cultured neurons, cultured/acute brain slices, or implanted “in vivo”. This paper provides an overview on recent achievements in our laboratory in the field of BCHIs leading to enhancement of signals transmission from nerve cells to chip or from chip to nerve cells with an emphasis on in vivo interfacing, either in terms of signal-to-noise ratio or of spatiotemporal resolution. Oxide-insulated chips featuring large-scale and high-resolution arrays of stimulation and recording elements are presented as a promising technology for high spatiotemporal resolution interfacing, as recently demonstrated by recordings obtained from hippocampal slices and brain cortex in implanted animals. Finally, we report on an automated tool for processing and analysis of acquired signals by BCHIs

Tracking germinal center B cells expressing germ-line immunoglobulin γ1 transcripts by conditional gene targeting

Germinal centers (GCs) represent the main sites for the generation of high-affinity, class-switched antibodies during T cell-dependent antibody responses. To study gene function specifically in GC B cells, we generated Cγ1-cre mice in which the expression of Cre recombinase is induced by transcription of the Ig γ1 constant region gene segment (Cγ1). In these mice, Cre-mediated recombination at the fas, Igβ, IgH, and Rosa26 loci occurred in GC B cells as early as 4 days after immunization with T cell-dependent antigens and involved >85% of GC B cells at the peak of the GC reaction. Less than 2% of IgM+ B cells showed Cre-mediated recombination. These cells carried few Ig somatic mutations, expressed germ-line Cγ1- and activation-induced cytidine deaminase-specific transcripts and likely include GC B cell founders and/or plasma cell precursors. Cre-mediated recombination involved most IgG1, but also a fraction of IgG3-, IgG2a-, IgG2b-, and IgA-expressing GC and post-GC B cells. This result indicates that a GC B cell can transcribe more than one downstream CH gens before undergoing class switch recombination. The efficient induction of Cre expression in GC B cells makes the Cγ1-cre allele a powerful tool for the genetic analysis of these cells, as well as, in combination with a suitable marker for Cre-mediated recombination, the tracking of class-switched memory B and plasma cells in vivo. To expedite the genetic analysis of GC B cells, we have established Cγ1-cre F1 embryonic stem cells, allowing further rounds of gene targeting and the cloning of compound mutants by tetraploid embryo complementation. © 2006 by The National Academy of Sciences of the USA