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Dorothea Haas Hongying Gan-Schreier Claus-Dieter Langhans Alexandros Anninos Gisela Haege Peter Burgard Andreas Schulze Georg F. Hoffmann Jürgen G. Okun 《Gene》2014
Biochemical detection of inborn errors of creatine metabolism or transport relies on the analysis of three main metabolites in biological fluids: guanidinoacetate (GAA), creatine (CT) and creatinine (CTN). Unspecific clinical presentation of the diseases might be the cause that only few patients have been diagnosed so far. We describe a LC–MS/MS method allowing fast and reliable diagnosis by simultaneous quantification of GAA, CT and CTN in urine, plasma and cerebrospinal fluid (CSF) and established reference values for each material. 相似文献
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H.U. Schweikert U.W. Tunn U.-F. Habenicht J. Arnold Th. Senge H. Schulze F.H. Schrder J.H.M. Blom O. Ennemoser W. Horniger G. Bartsch 《The Journal of steroid biochemistry and molecular biology》1993,44(4-6):573-576
Sex steroids are thought to play an essential role in the pathogenesis of human benign prostatic hyperplasia (BPH). Since recent studies in animal models and in men have shown that estrogens might be causally linked to the onset and maintenance of BPH, we examined the effect of 1-methyl-androsta-1,4-diene-3,17-dione (Atamestane), a newly developed aromatase inhibitor, in men with BPH. In an open multicenter study 49 men (mean age 70.1 years, range 55 to 84) with obstructive BPH were treated with atamestane (3 × 200 mg/day) for 3 months. Of the 49 patients 44 completed the treatment period; the other patients discontinued the study for reasons unrelated to treatment. With treatment BPH-related symptoms such as daytime voiding frequency, nycturia, peak flow and residual urine improved considerably; however, these parameters did not reach statistical significance. The mean prostatic volume decreased significantly from 74.2 ± 31.7 to 64.0 ± 31 ml (mean ± SD). Serum estrogen levels decreased markedly during treatment. In addition intraprostatic estrogen concentration decreased with treatment as compared to estrogen levels in hyperplastic prostates from untreated patients. The following conclusions can be drawn from this study: first, estrogens appear to have an important supportive role in established BPH, and second, estrogen deprivation improved BPH-related symptoms and reduced significantly prostatic volume. 相似文献
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Marina Mikhaylova Julia Bär Bas van Bommel Philipp Schätzle PingAn YuanXiang Rajeev Raman Johannes Hradsky Anja Konietzny Egor Y. Loktionov Pasham Parameshwar Reddy Jeffrey Lopez-Rojas Christina Spilker Oliver Kobler Syed Ahsan Raza Oliver Stork Casper C. Hoogenraad Michael R. Kreutz 《Neuron》2018,97(5):1110-1125.e14
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Ester B. M. Remmerswaal Paul L. Klarenbeek Nuno L. Alves Marieke E. Doorenspleet Barbera D. C. van Schaik Rebecca E. E. Esveldt Mirza M. Idu Ester M. M. van Leeuwen Nelly van der Bom-Baylon Antoine H. C. van Kampen Sven D. Koch Hanspeter Pircher Frederike J. Bemelman Anja ten Brinke Frank Baas Ineke J. M. ten Berge Rene A.W. van Lier Niek de Vries 《Journal of virology》2015,89(1):568-580
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RIN4 Functions with Plasma Membrane H+-ATPases to Regulate Stomatal Apertures during Pathogen Attack
Jun Liu James M. Elmore Anja T. Fuglsang Michael G. Palmgren Brian J. Staskawicz Gitta Coaker 《PLoS biology》2009,7(6)
Pathogen perception by the plant innate immune system is of central importance to plant survival and productivity. The Arabidopsis protein RIN4 is a negative regulator of plant immunity. In order to identify additional proteins involved in RIN4-mediated immune signal transduction, we purified components of the RIN4 protein complex. We identified six novel proteins that had not previously been implicated in RIN4 signaling, including the plasma membrane (PM) H+-ATPases AHA1 and/or AHA2. RIN4 interacts with AHA1 and AHA2 both in vitro and in vivo. RIN4 overexpression and knockout lines exhibit differential PM H+-ATPase activity. PM H+-ATPase activation induces stomatal opening, enabling bacteria to gain entry into the plant leaf; inactivation induces stomatal closure thus restricting bacterial invasion. The rin4 knockout line exhibited reduced PM H+-ATPase activity and, importantly, its stomata could not be re-opened by virulent Pseudomonas syringae. We also demonstrate that RIN4 is expressed in guard cells, highlighting the importance of this cell type in innate immunity. These results indicate that the Arabidopsis protein RIN4 functions with the PM H+-ATPase to regulate stomatal apertures, inhibiting the entry of bacterial pathogens into the plant leaf during infection. 相似文献
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Thomas Wiegand Wei-Chih Liao Ta Chung Ong Alexander Däpp Riccardo Cadalbert Christophe Copéret Anja Böckmann Beat H. Meier 《Journal of biomolecular NMR》2017,69(3):157-164
DNP (dynamic nuclear polarization)-enhanced solid-state NMR is employed to directly detect protein–DNA and protein–ATP interactions and identify the residue type establishing the intermolecular contacts. While conventional solid-state NMR can detect protein–DNA interactions in large oligomeric protein assemblies in favorable cases, it typically suffers from low signal-to-noise ratios. We show here, for the oligomeric DnaB helicase from Helicobacter pylori complexed with ADP and single-stranded DNA, that this limitation can be overcome by using DNP-enhanced spectroscopy. Interactions are established by DNP-enhanced 31P–13C polarization-transfer experiments followed by the recording of a 2D 13C–13C correlation experiment. The NMR spectra were obtained in less than 2 days and allowed the identification of residues of the motor protein involved in nucleotide binding. 相似文献
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Roldan M de Guia Adam J Rose Anke Sommerfeld Oksana Seibert Daniela Strzoda Annika Zota Yvonne Feuchter Anja Krones‐Herzig Tjeerd Sijmonsma Milen Kirilov Carsten Sticht Norbert Gretz Geesje Dallinga‐Thie Sven Diederichs Nora Klöting Matthias Blüher Mauricio Berriel Diaz Stephan Herzig 《The EMBO journal》2015,34(3):344-360
In mammals, glucocorticoids (GCs) and their intracellular receptor, the glucocorticoid receptor (GR), represent critical checkpoints in the endocrine control of energy homeostasis. Indeed, aberrant GC action is linked to severe metabolic stress conditions as seen in Cushing's syndrome, GC therapy and certain components of the Metabolic Syndrome, including obesity and insulin resistance. Here, we identify the hepatic induction of the mammalian conserved microRNA (miR)‐379/410 genomic cluster as a key component of GC/GR‐driven metabolic dysfunction. Particularly, miR‐379 was up‐regulated in mouse models of hyperglucocorticoidemia and obesity as well as human liver in a GC/GR‐dependent manner. Hepatocyte‐specific silencing of miR‐379 substantially reduced circulating very‐low‐density lipoprotein (VLDL)‐associated triglyceride (TG) levels in healthy mice and normalized aberrant lipid profiles in metabolically challenged animals, mediated through miR‐379 effects on key receptors in hepatic TG re‐uptake. As hepatic miR‐379 levels were also correlated with GC and TG levels in human obese patients, the identification of a GC/GR‐controlled miRNA cluster not only defines a novel layer of hormone‐dependent metabolic control but also paves the way to alternative miRNA‐based therapeutic approaches in metabolic dysfunction. 相似文献
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Decoupling the retention time of easily degradable and persistent substances using ultrafiltration membranes increases biogas production yield 下载免费PDF全文
Anja Schreiber Gerd‐Rainer Vollmer Uta Breuer Michael Nelles 《Engineering in Life Science》2016,16(1):60-66
The decoupling of the retention time of easily degradable and persistent substances relieves the degradation process from inhibitors and increases the biogas yield. Anaerobic digestion of maize silage was investigated in a pilot‐scale plant with a coupled ultrafiltration membrane. The aim of the study was the evaluation of the influence of the membrane‐based relief of the degradation process and the increase of the retention time of persistent substances. For that purpose, the fermenter content was separated into solid and liquid fractions. The solid fraction was recirculated to the fermenter for longer retention time and higher substrate degradation rates. The fermentation process was improved by the removal of the liquid fraction and adding volatile fatty acids. The results showed an increase of the biogas yield by 7.2% in comparison to the anaerobic digestion without membrane filtration. 相似文献