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Open access

Sandra R Dahl, Ingrid Nermoen, Ingeborg Brønstad, Eystein S Husebye, Kristian Løvås, and Per M Thorsby

for the patient’s age and sex. However, current immunoassays for testosterone are prone to interferences in the female reference range (low levels of testosterone) and can be inaccurate ( 7 , 8 , 9 ). Liquid chromatography–tandem mass spectrometry

Open access

Johanna Christina Penell, Mark M Kushnir, Lars Lind, Jonatan Bergquist, Jonas Bergquist, P Monica Lind, and Tord Naessen

concentrations seen in elderly ( 25 , 26 , 27 ). We recently developed highly sensitive and specific liquid chromatography-tandem mass spectrometry (LC-MS/MS) methods to identify and quantify a large number of steroids in small sample volumes ( 13 , 14 , 16

Open access

M P Schuijt, C G J Sweep, R van der Steen, A J Olthaar, N M M L Stikkelbroeck, H A Ross, and A E van Herwaarden

chromatography tandem mass spectrometry (ED-LC-MS/MS). LC-MS/MS enables the accurate, specific and matrix-independent measurement of testosterone with direct calibration. Equilibrium dialysis enables to separate the free- from protein-bound testosterone with

Open access

J A Tamblyn, C Jenkinson, D P Larner, M Hewison, and M D Kilby

stored at −80°C until use. Quantitative analysis of urinary de-conjugated vitamin D metabolites in spot urine samples was performed using a novel liquid chromatography tandem-mass spectrometry (LC–MS/MS) methodology. This was optimised from a method

Open access

Kristian Almstrup, Hanne Frederiksen, Anna-Maria Andersson, and Anders Juul

ArrayExpress repository ( www.ebi.ac.uk/arrayexpress ), under accession number E-MTAB-4187. Measurements of EDCs in urine In this study, we included data from liquid-chromatography tandem-mass-spectrometry (LC-MS/MS) measurements of triclosan (TCS

Open access

Amalie Carlsson, Kaspar Sørensen, Anna-Maria Andersson, Hanne Frederiksen, and Anders Juul

one out of nine environmental phenols measured by liquid chromatography-tandem mass spectrometry (LC–MS/MS) with prior enzymatic deconjugation ( 19 , 20 ). For the present study, first morning urine collected from the first of the two consecutive

Open access

Filippo Ceccato, Elisa Selmin, Giorgia Antonelli, Mattia Barbot, Andrea Daniele, Marco Boscaro, Mario Plebani, and Carla Scaroni

), because outdated radioimmunoassays were not able to differentiate compounds with structural similarity to the target molecule as cortisone (E) and F ( 9 , 10 ). The use of liquid chromatography-tandem mass spectrometry (LC-MS/MS) is increasing, and

Open access

M Krause, H Frederiksen, K Sundberg, F S Jørgensen, L N Jensen, P Nørgaard, C Jørgensen, P Ertberg, J H Petersen, U Feldt-Rasmussen, A Juul, K T Drzewiecki, N E Skakkebaek, and A M Andersson

-I. Chemical analysis of UV filters Maternal urine and serum samples were analyzed for seven different UV filters by isotope dilution TurboFlow-liquid chromatography–tandem mass spectrometry (LC–MS/MS) ( 25 ), and the measured concentrations have previously

Open access

Roberto Cosimo Melcangi, Livio Casarini, Marco Marino, Daniele Santi, Samantha Sperduti, Silvia Giatti, Silvia Diviccaro, Maria Grimoldi, Donatella Caruso, Guido Cavaletti, and Manuela Simoni

Context

Post-finasteride syndrome (PFS) occurs in patients with androgenic alopecia after suspension of the finasteride treatment, leading to a large variety of persistent side effects. Despite the severity of the clinical picture, the mechanism underlying the PFS symptoms onset and persistence is still unclear.

Objective

To study whether epigenetic modifications occur in PFS patients.

Methods

Retrospective analysis of a multicentric, prospective, longitudinal, case–control clinical trial, enrolling 16 PFS patients, compared to 20 age-matched healthy men. Main outcomes were methylation pattern of SRD5A1 and SRD5A2 promoters and concentration of 11 neuroactive steroids, measured by liquid chromatography-tandem mass spectrometry, in blood and cerebrospinal fluid (CSF) samples.

Results

SRD5A1 and SRD5A2 methylation analysis was performed in all blood samples (n = 16 PFS patients and n = 20 controls), in 16 CSF samples from PFS patients and in 13 CSF samples from controls. The SRD5A2 promoter was more frequently methylated in CSF of PFS patients compared to controls (56.3 vs 7.7%). No promoter methylation was detected in blood samples in both groups. No methylation occurred in the SRD5A1 promoter of both groups. Unmethylated controls compared to unmethylated SRD5A2 patients showed higher pregnenolone, dihydrotestosterone and dihydroprogesterone, together with lower testosterone CSF levels. Andrological and neurological assessments did not differ between methylated and unmethylated subjects.

Conclusions

For the first time, we demonstrate a tissue-specific methylation pattern of SRD5A2 promoter in PFS patients. Although we cannot conclude whether this pattern is prenatally established or induced by finasteride treatment, it could represent an important mechanism of neuroactive steroid levels and behavioural disturbances previously described in PFS.

Open access

Paal Methlie, Steinar Hustad, Ralf Kellman, Bjørg Almås, Martina M Erichsen, Eystein S Husebye, and Kristian Løvås

Franziska Randers, Otto Borholm, Øyvind S Holen and Ole-Thomas S Andersen for their excellent technical assistance and interesting discussions. References 1 Guo T Chan M Soldin SJ . Steroid profiles using liquid chromatography–tandem mass spectrometry