Development and validation of a Sensitive bioanalytical method for the quantitative estimation of Pantoprazole in human plasma samples by LC-MS/MS: Application to bioequivalence study
JOURNAL OF CHROMATOGRAPHY B-ANALYTICAL TECHNOLOGIES IN THE BIOMEDICAL AND LIFE SCIENCES
Authors: Challa, Balasekhara R.; Boddu, Sai H. S.; Awen, Bahlul Z.; Chandu, Babu R.; Bannoth, Chandrasekhar K.; Khagga, Mukkanti; Kanala, Kanchanamala; Shaik, Rihana P.
Abstract
The present study aims at developing a simple, sensitive and specific liquid chromatography-tandem mass spectrometry (LC-MS/MS) method for the quantification of pantoprazole sodium (PS) in human plasma using pantoprazole D3 (PSD3) as internal standard (IS). Chromatographic separation was performed on Zorbax SB-C18, 4.6 mm x 75 mm, 3 5 mu m, 80 angstrom column with an isocratic mobile phase composed of 10 mM ammonium acetate (pH 7 10) acetonitrile (30 70, v/v), pumped at 06 mL/min PS and PSD3 were detected with proton adducts at m/z 384 2 -> 200 1 and 387.1 -> 203 1 in multiple reaction monitoring (MRM) positive mode. respectively Precipitation method was employed in the extraction of PS and PSD3 from the biological matrix This method was validated over a linear concentration range of 10 00-3000 00 ng/mL with correlation coefficient (r) >= 0 9997. Intra- and inter-day precision of PS were found to be within the range of 1 13-1.54 and 1.76-2 86, respectively Both analytes were stable throughout freeze/thaw cycles, bench top and postoperative stability studies. This method was successfully utilized in the analysis of blood samples following oral administration of PS (40 mg) in healthy human volunteers (C) 2010 Elsevier B V All rights reserved.
Genome-wide association study of urinary albumin excretion rate in patients with type 1 diabetes
DIABETOLOGIA
Authors: Sandholm, Niina; Forsblom, Carol; Makinen, Ville-Petteri; McKnight, Amy Jayne; Osterholm, Anne-May; He, Bing; Harjutsalo, Valma; Lithovius, Raija; Gordin, Daniel; Parkkonen, Maija; Saraheimo, Markku; Thorn, Lena M.; Tolonen, Nina; Waden, Johan; Tuomilehto, Jaakko; Lajer, Maria; Ahlqvist, Emma; Mollsten, Anna; Marcovecchio, M. Loredana; Cooper, Jason; Dunger, David; Paterson, Andrew D.; Zerbini, Gianpaolo; Groop, Leif; Tarnow, Lise; Maxwell, Alexander P.; Tryggvason, Karl; Groop, Per-Henrik
Abstract
Aims/hypothesis An abnormal urinary albumin excretion rate (AER) is often the first clinically detectable manifestation of diabetic nephropathy. Our aim was to estimate the heritability and to detect genetic variation associated with elevated AER in patients with type 1 diabetes. Methods The discovery phase genome-wide association study (GWAS) included 1,925 patients with type 1 diabetes and with data on 24 h AER. AER was analysed as a continuous trait and the analysis was stratified by the use of antihypertensive medication. Signals with a p value < 10(-4) were followed up in 3,750 additional patients with type 1 diabetes from seven studies. Results The narrow-sense heritability, captured with our genotyping platform, was estimated to explain 27.3% of the total AER variability, and 37.6% after adjustment for covariates. In the discovery stage, five single nucleotide polymorphisms in the GLRA3 gene were strongly associated with albuminuria (p < 5 x 10(-8)). In the replication group, a nominally significant association (p = 0.035) was observed between albuminuria and rs1564939 in GLRA3, but this was in the opposite direction. Sequencing of the surrounding genetic region in 48 Finnish and 48 UK individuals supported the possibility that population-specific rare variants contribute to the synthetic association observed at the common variants in GLRA3. The strongest replication (p = 0.026) was obtained for rs2410601 between the PSD3 and SH2D4A genes. Pathway analysis highlighted natural killer cell mediated immunity processes. Conclusions/interpretation This study suggests novel pathways and molecular mechanisms for the pathogenesis of albuminuria in type 1 diabetes.