Effect of statin therapy on serum activity of proteinases and cytokines in patients with abdominal aortic aneurysm

Bernd Muehling1, Alexander Oberhuber1, Hubert Schelzig1, Gisela Bischoff1, Nikolaus Marx2, Ludger Sunder-Plassmann1, Karl H Orend11Department of Thoracic and Vascular surgery; 2Department of Internal Medicine, University of Ulm, Ulm, GermanyBackground and aims: Metalloproteinases (MMPs) are considered to be key enzymes in the pathogenesis of abdominal aortic aneurysms (AAA), with elevated levels in diseased aorta and in patient sera. Statins seem to exert an inhibitory effect on MMP activity in the aortic wall. No data exist on the effect of statins on serum activity of MMPs and inflammatory cytokines (interleukins, IL).Methods: The serum activities of MMP2 and MMP9, osteoprotegerin (OPG), and IL6 and IL10 in 63 patients undergoing elective infrarenal aneurysm repair were measured on the day before surgery. Levels were correlated to statin therapy and aneurysm diameter.Results: There was no significant difference between the two groups in the activity of circulating levels of MMP2/9, OPG, and IL6/10 in patients with infrarenal aortic aneurysm. IL6 levels in patients with AAA larger than 6 cm were significantly elevated; differences in serum activities of MMP2/9, OPG, and IL10 were not related to AAA diameter.Conclusion: Serum activities of MMP2/9, OPG, and IL6/10 are not correlated to statin therapy; IL6 levels are higher in patients with large aneurysms. Hence the effect of statin therapy in the treatment of aneurismal disease remains to be elucidated.Keywords: biomarkers, aneurismal disease, statin therap

Split Nitrogen Application Improves Wheat Baking Quality by Influencing Protein Composition Rather Than Concentration

The use of late nitrogen (N) fertilization (N application at late growth stages of wheat, e.g., booting, heading or anthesis) to improve baking quality of wheat has been questioned. Although it increases protein concentration, the beneficial effect on baking quality (bread loaf volume) needs to be clearly understood. Two pot experiments were conducted aiming to evaluate whether late N is effective under controlled conditions and if these effects result from increased N rate or N splitting. Late N fertilizers were applied either as additional N or split from the basal N at late boot stage or heading in the form of nitrate-N or urea. Results showed that late N fertilization improved loaf volume of wheat flour by increasing grain protein concentration and altering its composition. Increasing N rate mainly enhanced grain protein quantitatively. However, N splitting changed grain protein composition by enhancing the percentages of gliadins and glutenins as well as certain high molecular weight glutenin subunits (HMW-GS), which led to an improved baking quality of wheat flour. The late N effects were greater when applied as nitrate-N than urea. The proportions of glutenin and x-type HMW-GS were more important than the overall protein concentration in determining baking quality. N splitting is more effective in improving wheat quality than the increase in the N rate by late N, which offers the potential to cut down N fertilization rates in wheat production systems

Metabolite profiling of wheat flag leaf and grains during grain filling phase as affected by sulfur fertilisation

Zoerb C, Steinfurth D, Gödde V, Niehaus K, Muehling KH. Metabolite profiling of wheat flag leaf and grains during grain filling phase as affected by sulfur fertilisation. Functional Plant Biology. 2012;39(2):156-166.Increasing prices for wheat products and fertilisers call for an adjusted agricultural management to maintain yield and to improve product quality. With the increased use of sulfur-free fertilisers in modern cropping systems and the decrease of atmospheric sulfur emissions by industry, sulfur has become a major limiting factor for crop production. The presented data showed that by using GC-MS it was possible to quantitatively detect a set of 72 different metabolites including amino acids, organic acids, sugars, sugar phosphates, and sugar alcohols, phenolic compounds and nucleotides from wheat grains and flag leaves of a pot experiment. A principal component analysis (PCA) revealed a clear separation of flag leaves and grains and a clear separation of non-fertilised and fertilised flag leaves. It could further be shown by PCA, that the low level sulfur fertilisation is also separated from the higher fertilised grains. A considerable influence of the sulfur fertilisation not only on sulfur rich amino acids but also on the sugar metabolism was detected. With increasing sulfur fertilisation six sugars and sugar derivates in the grain such as glucose-6P, galactose, trehalose, cellobiose, melibiose, fumarate, glycerate and the nucleotide uracil were enhanced. Therefore, it was concluded that photosynthesis was limited in developing plants suffering from sulfur deficiency. Late sulfur fertilisation is a procedure that can help to prevent sulfur deficiency. A latent sulfur deficiency at ear emergence can be compensated by late sulfur fertilisation, as wheat plants can replenish sulfate deficits within a short time

Greenhouse gas emissions in biogas production systems

There is growing concern that greenhouse gas (GHG) emissions during agricultural energy crop production might negate GHG emission savings. Here a study is presented evaluating two favourable biogas crops in two agro-ecological regions of Northern Germany for their productivity and GHG emissions. A 2-year field experiment was conducted at two sites with different soil type but similar temperate maritime climate. We compared silage maize which is currently the standard crop grown for biogas fermentation purposes to an alternative bioenergy crop at each site. Three forms of fertilizers/manures were given: calcium ammonium nitrate, cattle / pig slurry, biogas waste. GHG emissions of all biogas crops were strongly dominated by N2O emissions. There were very short CH4 emission events immediately after application of slurry and biogas waste. N2O flux patterns usually followed fertilizer application events in all crops and at both sites. Flux patterns indicated pronounced effects of soil moisture which was also seen as responsible for the 20–30 % higher N2O fluxes in maize compared to the other tested crops. Overall, N2O emissions at the loamy soil site were at least 3 times higher than in all crops examined at the site with sandy soil. The present study provides a very good basis for the assessment of direct emissions of greenhouse gases from relevant biogas crops in North-West Europe. It is intended to use measured and simulated data on soil moisture and the N/C inputs by fertilizer/manure application as drivers for a nitrification/denitrification module linked to a crop growth model

Identification of boron-binding proteins supports a function of boron at the cell membrane

Our current understanding of boron’s roles in plants is still limited to the formation of B-rhamnogalacturonan-crosslinks in the cell wall, but deficiency symptoms in plants and animals point to additional functions of boron (B) in cell membranes. However, no membrane-bound molecules interacting with B have been isolated so far.In the present study we address the hypothesis that boron exerts a physiological function at membranes by crosslinking membrane-bound proteins.Boron-interacting membrane proteins were isolated from root microsomal preparations of arabidopsis (Arabidopsis thaliana) and maize (Zea mays) using phenylboronate affinity chromatography, subsequently separated by two-dimensional gel electrophoresis and identified using MALDI-TOF peptide mass fingerprinting.A relatively large number of B-binding membrane proteins was detected, of which sixteen (A. thaliana) and nine (Z. mays) were identified. Common to both species were the beta subunit of mitochondrial ATP synthase, several beta-glucosidases, a luminal binding protein and fructose bisphosphate aldolase. Binding of these proteins to B was significantly reduced after 5 days of B deprivation in A. thaliana. Plants grown under B deficiency also exhibited an altered protein composition of membrane microdomains. This combined with the fact that many of the B-binding proteins are components of membrane rafts, supports the hypothesis that B may indeed play a function in plant membranes by crosslinking glycoproteins, and may be involved in their recruiting to membrane microdomains

Influence of operating conditions on loads and fatigue strength in a rod column of PCP

Актуальность исследования обусловлена необходимостью повышения надежности и ресурса штанговых винтовых насосных установок, используемых для осложненных условий эксплуатации скважин, поскольку они имеют низкую надежность в сравнении с электроцентробежными насосами, что ограничивает их применение. Винтовые насосные установки используются в скважинных условиях, характеризующихся высокой вязкостью откачиваемой пластовой жидкости (более 30 мПа·с) и высоким содержанием механических примесей в ней (коэффициент взвешенных частиц более 500 мг/литр). Опыт эксплуатации винтовых насосных установок показывает, что надежность насосных установок зависит в первую очередь от надежности штанговой колонны. Помимо крутящей нагрузки, необходимой для передачи вращения от асинхронного двигателя к винтовому насосу, погруженному на расстояние более одного километра от устья скважины, штанговая колонна испытывает растягивающие нагрузки от веса насосных штанг и осевой нагрузки винтового насоса, а также изгибающие нагрузки, вызванные пространственным искривлением ствола скважины. Цель исследования заключается в оценке влияния различных факторов эксплуатации на нагрузки, действующие на колонну насосных штанг в процессе эксплуатации скважины, а также на усталостную прочность насосных штанг. Методы: методика расчета штанговых колонн винтовых насосных установок с учетом осевых, крутящих и изгибающих нагрузок, учитывающая процессы трения штанговой колонны о насосно-компрессорные трубы, возникающие от Эйлеровых сил прижатия штанг к трубам из-за пространственного искривления ствола скважины, реализованная на языке программирования Python; факторный анализ нагрузок, действующих на привод насосной установки. Результаты. С помощью программного обеспечения, реализованного на языке программирования Python, произведены расчеты, показавшие влияние различных осложняющих факторов на величину нагрузок на штанговую колонну. Показано влияние нагрузок вследствие воздействия геолого-технических и технологических параметров на усталостную прочность насосных штанг. Разработанное программное обеспечение позволяет учесть степень влияния осложняющих факторов на стадии подбора компоновки винтовой насосной установки, а также в процессе эксплуатации и тем самым существенно увеличить межремонтный период работы штанговых винтовых насосных установок.The relevance of the research is caused by the need to increase the reliability and resource of progressing cavity pumps, used in complicated well operating conditions, since they have low reliability in comparison with electrical submersible pumps, that limits their application. Progressing cavity pumps are used in well conditions characterized by a high viscosity of the pumped fluid (more than 30 mPa·s) and a high content of solid particles in it (the coefficient of suspended particles is more than 500 mg/liter). Experience in operating progressing cavity pumps shows that the reliability of pumping installations depends primarily on the reliability of the rod string. In addition to the torque load required to transfer the rotation from the induction motor to the screw pump, immersed on more than one kilometer from the wellhead, the sucker string experiences tensile loads from the weight of the pump rods and the axial load of the screw pump, as well as bending loads caused by the spatial curvature of the wellbore. The paper proposes the implementation of methodology for calculating the sucker rod columns of progressing cavity pumps with regard to axial, torsional and bending loads in the Python programming language. The proposed method for calculating the rod column of a screw pumping unit takes into account the rod column friction on tubing pipes arising from the Eulerian forces pressing the rods to the pipes due to the spatial curvature of the wellbore. Using software implemented in the python programming language, the authors have made calculations that showed the influence of various complicating factors on the magnitude of the loads on the rod string. As a result of calculations of the fatigue strength of the pump rods, cyclic loads during the rotation of the rods in the local sections of the local curvature of the wellbore was shown. The developed software allows you to take into account the degree of influence of complicated well operating conditions at the design stage, and thus, significantly increase the turnaround time of the rod screw pumping units. The main aim of the research is to assess the influence of various operating factors on the loads acting on the string of pump rods during well operation, as well as on the fatigue strength of the pump rods. Methods. Using software implemented in the python programming language, calculations were performed that showed the influence of various complicating factors on the magnitude of the loads on the rod string. The paper demonstrated the effect of loads on the fatigue strength of sucker rods caused by cyclic loads during rotation of the rods in the areas of local curvature of the wellbore. The developed software allows taking into account the degree of influence of complicating factors at the stage of selecting the layout of a PCP, as well as during operation, and thereby significantly increasing the overhaul period of PCP operation

Fast responses of metabolites in Vicia faba L. to moderate NaCl stress

Geilfus C-M, Niehaus K, Goedde V, et al. Fast responses of metabolites in Vicia faba L. to moderate NaCl stress. Plant Physiology and Biochemistry. 2015;92:19-29.Salt stress impairs global agricultural crop production by reducing vegetative growth and yield. Despite this importance, a number of gaps exist in our knowledge about very early metabolic responses that ensue minutes after plants experience salt stress. Surprisingly, this early phase remains almost as a black box. Therefore, systematic studies focussing on very early plant physiological responses to salt stress (in this case NaCl) may enhance our understanding on strategies to develop crop plants with a better performance under saline conditions. In the present study, hydroponically grown Vicia faba L. plants were exposed to 90 min of NaCl stress, whereby every 15 min samples were taken for analyzing short-term physiologic responses. Gas chromatography-mass spectrometry-based metabolite profiles were analysed by calculating a principal component analysis followed by multiple contrast tests. Follow-up experiments were run to analyze downstream effects of the metabolic changes on the physiological level. The novelty of this study is the demonstration of complex stress-induced metabolic changes at the very beginning of a moderate salt stress in V. faba, information that are very scant for this early stage. This study reports for the first that the proline analogue trans-4-hydroxy-L-proline, known to inhibit cell elongation, was increasingly synthesized after NaCl-stress initiation. Leaf metabolites associated with the generation or scavenging of reactive oxygen species (ROS) were affected in leaves that showed a synchronized increase in ROS formation. A reduced glutamine synthetase activity indicated that disturbances in the nitrogen assimilation occur earlier than it was previously thought under salt stress. (C) 2015 Elsevier Masson SAS. All rights reserved