Simultaneous quantification of serum symmetric dimethylarginine, asymmetric dimethylarginine and creatinine for use in a routine clinical laboratory.

Background: Symmetric dimethylarginine (SDMA) and asymmetric dimethylarginine (ADMA) are naturally occurring amino acids classed as uraemic toxins by the European Uremic Toxins Work Group. SDMA is principally excreted through the kidneys and is a well-known renal function marker, and ADMA is a potent inhibitor of nitric oxide production. Here, we describe the development of a rapid and sensitive liquid chromatography tandem mass spectrometry method for simultaneous measurement of SDMA, ADMA and creatinine.

Development and validation of a novel 7α-hydroxy-4-cholesten-3-one (C4) liquid chromatography tandem mass spectrometry method and its utility to assess pre-analytical stability.

Objectives: 7α-Hydroxy-4-cholesten-3-one (C4) is the common intermediary of both primary bile acids. C4 is recommended by the British Society of Gastroenterology for the investigation of bile acid diarrhoea (BAD) in patients with chronic diarrhoea. This project aimed to develop and validate an assay to quantitate C4 in serum and assess the stability of C4 in unseparated blood.

Diurnal 11-ketotestosterone and 17-hydroxyprogesterone saliva profiles in paediatric classical congenital adrenal hyperplasia.

Objectives: The most suitable biochemical markers for therapy adjustment in patients with congenital adrenal hyperplasia are controversial. 11-Oxygenated androgens are a promising new approach. The objective of this study was to investigate the diurnal rhythm of 11-ketotestosterone in children and adolescents in saliva and to correlate it with salivary 17-hydroxyprogesterone.

Development of diagnostic algorithm for Cushing's syndrome: a tertiary centre experience.

Purpose: No consensus exists as the gold standard for Cushing's Syndrome (CS) screening. This study aimed to evaluate the diagnostic accuracy and utility of late-night salivary cortisol (LNSC) and cortisone (LNSE), overnight dexamethasone suppression test (ODST), and urinary free cortisol (UFC) in developing a screening algorithm for CS.

Methods: A retrospective, single-centre analysis on 93 adult patients referred to the Oxford Centre for Diabetes, Endocrinology, and Metabolism for CS evaluation (2017-2022).

Resumption of ovulation in anovulatory women with PCOS and obesity is associated with reduction of 11β-hydroxyandrostenedione concentrations.

Study Question: Is resumption of ovulation after a 6-month lifestyle intervention in women with PCOS and obesity associated with differential changes in endocrine and metabolic parameters (weight, insulin resistance, anti-Müllerian hormone (AMH), and androgens) compared to women with PCOS who remained anovulatory?

Summary Answer: Resumption of ovulation after a 6-month lifestyle intervention in women with PCOS and obesity is associated with changes in serum 11β-hydroxyandrostenedione (11OHA4) concentrations.

What Is Known Already: Lifestyle interventions have been shown to reduce clinical and biochemical hyperandrogenism in women with PCOS. Weight loss of 5-10% may reverse anovulatory status, thereby increasing natural conception rates.