Search Results - "Bollenbach, Alexander"

GC-MS Studies on the Conversion and Derivatization of γ-Glutamyl Peptides to Pyroglutamate (5-Oxo-Proline) Methyl Ester Pentafluoropropione Amide Derivatives by Bollenbach, Alexander, Tsikas, Dimitrios

“…Glutathione (γ-L-glutamyl-L-cysteinyl-glycine, γ-Glu-Cys-Gly) is the most abundant intra-cellular dicarboxylic tripeptide with multiple physiological roles. In…”
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Asymmetric dimethylarginine (ADMA), symmetric dimethylarginine (SDMA) and homoarginine (hArg): the ADMA, SDMA and hArg paradoxes by Tsikas, Dimitrios, Bollenbach, Alexander, Hanff, Erik, Kayacelebi, Arslan Arinc

“…N -Methylation of L-arginine (Arg) residues in certain proteins by protein arginine methyltransferases and subsequent proteolysis yields N…”
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Two-Step Derivatization of Amino Acids for Stable-Isotope Dilution GC-MS Analysis: Long-Term Stability of Methyl Ester-Pentafluoropropionic Derivatives in Toluene Extracts by Baskal, Svetlana, Bollenbach, Alexander, Tsikas, Dimitrios

“…Analysis of amino acids by gas chromatography-mass spectrometry (GC-MS) requires at least one derivatization step to enable solubility in GC-MS-compatible…”
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Development, validation of a GC–MS method for the simultaneous measurement of amino acids, their PTM metabolites and AGEs in human urine, and application to the bi-ethnic ASOS study with special emphasis to lysine by Baskal, Svetlana, Bollenbach, Alexander, Mels, Catharina, Kruger, Ruan, Tsikas, Dimitrios

“…A gas chromatography-mass spectrometry (GC–MS) method was developed and validated in relevant concentration ranges for the simultaneous measurement of l…”
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Unusual Derivatization of Methylmalonic Acid with Pentafluorobenzyl Bromide to a Tripentafluorobenzyl Derivative and Its Stable-Isotope Dilution GC-MS Measurement in Human Urine by Bollenbach, Alexander, Baskal, Svetlana, Mels, Catharina, Kruger, Ruan, Tsikas, Dimitrios

“…Methylmalonic acid (MMA) is a very short dicarboxylic acid (methylpropanedioic acid; CH3CH(COOH)2; pKa1, 3.07; pKa2, 5.76) associated with vitamin B12…”
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GC-MS Discrimination of Citrulline from Ornithine and Homocitrulline from Lysine by Chemical Derivatization: Evidence of Formation of N5-Carboxy-ornithine and N6-Carboxy-lysine by Baskal, Svetlana, Bollenbach, Alexander, Tsikas, Dimitrios

“…Derivatization of amino acids by 2 M HCl/CH3OH (60 min, 80 °C) followed by derivatization of the intermediate methyl esters with pentafluoropropionic anhydride…”
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Stable-Isotope Dilution GC–MS Measurement of Metformin in Human Serum and Urine after Derivatization with Pentafluoropropionic Anhydride and Its Application in Becker Muscular Dystrophy Patients Administered with Metformin, l-Citrulline, or Their Combination by Baskal, Svetlana, Bollenbach, Alexander, Henzi, Bettina, Hafner, Patricia, Fischer, Dirk, Tsikas, Dimitrios

“…Metformin (N,N-dimethylguanylguanidine) is one of the most prescribed drugs with pleiotropic, exerted in part by not fully elucidated mechanisms of action. We…”
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GC–MS measurement of spermidine and putrescine in serum of elderly subjects: intriguing association between spermidine and homoarginine by Hanff, Erik, Bollenbach, Alexander, Beckmann, Bibiana, Brunner, Gorig, Tsikas, Dimitrios

“…Gas chromatography–mass spectrometry (GC–MS) methods were developed, validated and used to measure serum spermidine (SPD) and putrescine (PUT) in 9…”
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Whole-body arginine dimethylation is associated with all-cause mortality in adult renal transplant recipients by Post, Adrian, Bollenbach, Alexander, Bakker, Stephan J. L., Tsikas, Dimitrios

“…Arginine residues in proteins can be singly or doubly methylated post-translationally. Proteolysis of arginine-methylated proteins provides monomethyl…”
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Asymmetric dimethylation and citrullination in the LEW.1AR1-iddm rat, an animal model of human type 1 diabetes, and effects of anti-TCR/anti-TNF-α antibody-based therapy by Bollenbach, Alexander, Tsikas, Dimitrios, Lenzen, Sigurd, Jörns, Anne

“…The LEW.1AR1- iddm rat is an animal model of human type 1 diabetes (T1D). We determined by GC–MS the extent of asymmetric dimethylation (prADMA) and…”
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Urinary excretion of amino acids and their advanced glycation end-products (AGEs) in adult kidney transplant recipients with emphasis on lysine: furosine excretion is associated with cardiovascular and all-cause mortality by Baskal, Svetlana, Post, Adrian, Kremer, Daan, Bollenbach, Alexander, Bakker, Stephan J. L., Tsikas, Dimitrios

“…Arginine (Arg) and lysine (Lys) moieties of proteins undergo various post-translational modifications (PTM) including enzymatic N G - and N ε -methylation and…”
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Urinary albumin-to-creatinine ratio is inversely related to nitric oxide synthesis in young black adults: the African-PREDICT study by Craig, Ashleigh, Mels, Catharina M C, Schutte, Aletta E, Bollenbach, Alexander, Tsikas, Dimitrios, Schwedhelm, Edzard, Kruger, Ruan

“…Hypertension is common in black populations and is known to be associated with low nitric oxide (NO) bioavailability. We compared plasma and urinary NO-related…”
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Advanced Glycation End-Products (AGEs) of Lysine and Effects of Anti-TCR/Anti-TNF-α Antibody-Based Therapy in the LEW.1AR1 -iddm Rat, an Animal Model of Human Type 1 Diabetes by Baskal, Svetlana, Tsikas, Stefanos A, Begou, Olga, Bollenbach, Alexander, Lenzen, Sigurd, Jörns, Anne, Tsikas, Dimitrios

“…The LEW.1AR1- rat is an animal model of human type 1 diabetes (T1D). Previously, we have shown that combination with anti-TCR/anti-TNF-α antibody-based therapy…”
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S-Adenosyl-L-methionine towards hepatitis C virus expression: Need to consider S-Adenosyl-L-methionine’s chemistry, physiology and pharmacokinetics by Tsikas, Dimitrios, Hanff, Erik, Bollenbach, Alexander

“…S-Adenosyl-L-methionine(SAM) is a cofactor serving as a methyl donor in numerous enzymatic reactions. It has been reported that SAM has the potential to modify…”
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Synthesis of homoagmatine and GC–MS analysis of tissue homoagmatine and agmatine: evidence that homoagmatine but not agmatine is a metabolite of pharmacological L-homoarginine in the anesthetized rat by Tsikas, Dimitrios, Bollenbach, Alexander, Hanff, Erik, Beckmann, Bibiana, Redfors, Björn

“…Low L-homoarginine (hArg) concentrations in human blood and urine are associated with renal and cardiovascular morbidity and mortality, yet the underlying…”
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Isolation and functional characterization of the novel Clostridium botulinum neurotoxin A8 subtype by Kull, Skadi, Schulz, K Melanie, Weisemann, Jasmin, Kirchner, Sebastian, Schreiber, Tanja, Bollenbach, Alexander, Dabrowski, P Wojtek, Nitsche, Andreas, Kalb, Suzanne R, Dorner, Martin B, Barr, John R, Rummel, Andreas, Dorner, Brigitte G

“…Botulism is a severe neurological disease caused by the complex family of botulinum neurotoxins (BoNT). Based on the different serotypes known today, a…”
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Asymmetric and Symmetric Protein Arginine Dimethylation: Concept and Postprandial Effects of High-Fat Protein Meals in Healthy Overweight Men by Bollenbach, Alexander, Huneau, Jean-François, Mariotti, François, Tsikas, Dimitrios

“…Asymmetric and symmetric dimethylarginine (ADMA and SDMA, respectively) are risk factors for the cardiovascular and renal systems. There is a paucity of data…”
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Upregulation of the TRPA1 Ion Channel in the Gastric Mucosa after Iodoacetamide-Induced Gastritis in Rats: A Potential New Therapeutic Target by Csekő, Kata, Pécsi, Dániel, Kajtár, Béla, Hegedűs, Ivett, Bollenbach, Alexander, Tsikas, Dimitrios, Szabó, Imre László, Szabó, Sándor, Helyes, Zsuzsanna

“…Acute gastritis is often untreatable by acid secretion-inhibiting drugs. Understanding the protective mechanisms including the role of Transient Receptor…”
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Effect of renal function on homeostasis of asymmetric dimethylarginine (ADMA): studies in donors and recipients of renal transplants by Said, M. Yusof, Douwes, Rianne M., van Londen, Marco, Minović, Isidor, Frenay, Anne-Roos, de Borst, Martin H., van den Berg, Else, Heiner-Fokkema, M. Rebecca, Kayacelebi, Arslan Arinc, Bollenbach, Alexander, van Goor, Harry, Navis, Gerjan, Tsikas, Dimitrios, Bakker, Stephan J. L.

“…Asymmetric dimethylarginine (ADMA) is a methylated form of arginine and an endogenous nitric oxide synthase inhibitor. Renal function decline is associated…”
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Ion Channel Function and Cross-Species Determinants in Viral Assembly of Nonprimate Hepacivirus p7 by Walter, Stephanie, Bollenbach, Alexander, Doerrbecker, Juliane, Pfaender, Stephanie, Brown, Richard J P, Vieyres, Gabrielle, Scott, Claire, Foster, Richard, Kumar, Abhinav, Zitzmann, Nicole, Griffin, Stephen, Penin, François, Pietschmann, Thomas, Steinmann, Eike

“…Nonprimate hepacivirus (NPHV), the closest homolog of hepatitis C virus (HCV) described to date, has recently been discovered in horses. Even though the two…”
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