Differential extraction of endogenous and exogenous 25-OH-vitamin D from serum makes the accurate quantification in liquid chromatography-tandem mass spectrometry assays challenging.

abstract：BACKGROUND:Macroprolactin is a high molecular mass complex of prolactin that may be the cause of elevated serum prolactin as determined by immunoassay. The composition of macroprolactin and its reactivity in immunoassays are variable but the complex has minimal bioactivity in vivo. Hyperprolactinaemia due to unrecogniz...

journal_title：Annals of clinical biochemistry

authors： Ellis AR,Fahie-Wilson M,Axcell M,Sands K,Hill RP

更新日期：2006-01-01 00:00:00

abstract：BACKGROUND:Supported liquid extraction (SLE) techniques are relatively new compared to other sample preparation approaches such as solid phase extraction (SPE), liquid-liquid extraction (LLE) and protein precipitation (PPE). We investigated the use of SLE as an alternative to SPE for the liquid chromatography tandem ma...

journal_title：Annals of clinical biochemistry

authors： Owen LJ,Keevil BG

更新日期：2013-09-01 00:00:00

abstract：BACKGROUND:The haptoglobin (Hp) 2-2 phenotype has been known to have less antioxidative activity than Hp 1-1 and Hp 2-1. However, few have reported the relationship between oxidative stress and Hp phenotypes by using oxidized LDL. The relationship between Hp phenotypes and oxidative stress was therefore investigated in...

journal_title：Annals of clinical biochemistry

authors： Lee YW,Min WK,Chun S,Lee W,Park H,Lee YK,Lee DH,Son JE

更新日期：2004-11-01 00:00:00

abstract：BACKGROUND:Oxidative stress may play an aetiological role in the development and progression of cardiovascular disease (CVD). However, evidence on its biochemical markers has been controversial. This article aimed to assess the role of F2-isoprostanes, a marker for measuring in vivo lipid oxidation, as a biomarker for ...

journal_title：Annals of clinical biochemistry

authors： Zhang ZJ

更新日期：2013-03-01 00:00:00

abstract：BACKGROUND:Neutrophilic polymorphonuclear leukocytes play a crucial role in the host defence against bacterial and fungal infections. They participate in the inflammatory response through the liberation of peptides and enzymes like myeloperoxidase (MPO). Therefore, MPO has a potential as a marker enzyme for the diagnos...

journal_title：Annals of clinical biochemistry

authors： Hasmann A,Wehrschuetz-Sigl E,Marold A,Wiesbauer H,Schoeftner R,Gewessler U,Kandelbauer A,Schiffer D,Schneider KP,Binder B,Schintler M,Guebitz GM

更新日期：2013-05-01 00:00:00

abstract：BACKGROUND:Neuroendocrine tumours are slow growing tumours known to secrete a variety of vasoactive peptides which give rise to symptoms of the carcinoid syndrome. The diagnosis and monitoring of patients with neuroendocrine tumours is undertaken in many centres using 24 h urinary measurement of 5-hydroxyindoleacetic a...

journal_title：Annals of clinical biochemistry

authors： Adaway JE,Dobson R,Walsh J,Cuthbertson DJ,Monaghan PJ,Trainer PJ,Valle JW,Keevil BG

更新日期：2016-09-01 00:00:00

abstract：:The present study was designed to re-evaluate the radioimmunoassay for desmosine in urine, which is currently used as a measure of elastin metabolism. Using ion exchange chromatography, gel filtration and affinity chromatography it was shown that at least five other compounds in hydrolysates of human urine competed fo...

journal_title：Annals of clinical biochemistry

authors： Starcher B,Scott M

更新日期：1992-01-01 00:00:00

abstract：:This review describes the development and application of a novel test to determine levels of human immunoreactive trypsin, an enzyme produced solely by the pancreas, in biological fluids. Being organ-specific, the assay of immunoreactive trypsin should be an ideal marker of pancreatic function, and this is supported b...

journal_title：Annals of clinical biochemistry

authors： Stagg BH,Wood TP

更新日期：1979-05-01 00:00:00

abstract：BACKGROUND:Thiopurine methyltransferase (TPMT) catalyses the S-methylation of 6-thiopurine drugs, which are commonly used in the treatment of autoimmune diseases, leukaemia and organ transplantation. TPMT activity is polymorphic as a result of gene mutations. Ethnic variations in phenotype and genotype have been identi...

journal_title：Annals of clinical biochemistry

authors： Laróvere LE,de Kremer RD,Lambooy LH,De Abreu RA

更新日期：2003-07-01 00:00:00

abstract：:The System 1 produced results for glucose and urea which were precise and accurate. It proved suitable as a general laboratory instrument as it samples 28 mul of specimen, is able to calibrate itself, produces results in three minutes, and has the capacity to analyse 56 samples an hour. ...

journal_title：Annals of clinical biochemistry

authors： Potezny N,Quelch J,Fuller B,Geary TD

更新日期：1977-09-01 00:00:00

abstract：:Direct assays have been described for the estimation of progesterone in serum and saliva. Both methods showed good inter-assay precision over a year, and the serum assay is now being used routinely in clinical laboratories. A highly significant correlation was obtained for progesterone concentrations in matched serum ...

journal_title：Annals of clinical biochemistry

authors： Webley GE,Edwards R

更新日期：1985-11-01 00:00:00

abstract：:An automated method for the determination of N-acetyl-beta-D-glucosaminidase in serum or plasma using p-nitrophenol (pNP) N-acetyl-beta-D-glucosamine as substrate and a Pye Unicam AURA system is described. Normal samples had activities of 853 +/- 146 (SD) nmol pNP liberated/ml/h, with intra-assay coefficient of variat...

journal_title：Annals of clinical biochemistry

authors： Moore JC,Morris JE

更新日期：1982-05-01 00:00:00

abstract：:A group of international experts prepared two lists of drugs with their serum/plasma and urine concentrations, which should be used when evaluating the performance of a new laboratory method. The two lists were verified by running in vitro interference studies in three European laboratories on Hitachi instruments. The...

journal_title：Annals of clinical biochemistry

authors： Sonntag O,Scholer A

更新日期：2001-07-01 00:00:00

abstract：:The effects of inhibition of inosine monophosphate dehydrogenase (IMPDH), the rate-limiting enzyme in guanine nucleotide de novo synthesis, on cell growth, cell viability, endogenous nucleotide concentrations and concentrations of extracellular nucleosides and bases were studied in Molt F4 human malignant lymphoblasts...

journal_title：Annals of clinical biochemistry

authors： Stet EH,De Abreu RA,Bökkerink JP,Lambooy LH,Vogels-Mentink TM,Keizer-Garritsen JJ,Trijbels FJ

更新日期：1994-03-01 00:00:00

abstract：:Many techniques for the estimation of specific proteins measure light scattered by, or the turbidity of, suspensions of antigen:antibody aggregates formed in fluid-phase reactions. Although the shapes of reaction curves obtained are well documented, interpretation of the data in relation to the laws of light scatterin...

journal_title：Annals of clinical biochemistry

authors： Deverill I,Lock RJ

更新日期：1983-07-01 00:00:00

abstract：:Free and total reduced concentrations of D-penicillamine have been measured in the plasma of rheumatoid arthritis patients by HPLC and electro-chemical detection. A reverse-phase ion-pair separation in conjunction with a dual porous graphite electrode satisfied the requirements of robustness, sensitivity, selectivity ...

journal_title：Annals of clinical biochemistry

authors： Webb BA,Richardson SJ,Haslock I

更新日期：1988-03-01 00:00:00

abstract：BACKGROUND:Adding or incorporating clinical interpretative comments on biochemistry results is widespread in UK laboratories; although this consumes considerable human resource, there is still little evidence to suggest that it is either effective or appreciated by our clinical colleagues. I therefore decided to survey...

journal_title：Annals of clinical biochemistry

authors： Barlow IM

更新日期：2008-01-01 00:00:00

abstract：:Serum total sialic acid (TSA) has gained medical interest, particularly as a cardiovascular risk factor and it has been hypothesized that serum levels relate to serum acute phase proteins, some of which are sialylated. We assayed serum TSA and also lipid associated sialic acid (LASA) in 50 normal individuals (24 male)...

journal_title：Annals of clinical biochemistry

authors： Haq M,Haq S,Tutt P,Crook M

更新日期：1993-07-01 00:00:00

abstract：:Three sensitive assays (Behring, Organon and LKB-Pharmacia) for measurement of serum thyrotropin (TSH) were evaluated. All three assays showed good precision, sensitivity, linearity and for practical purposes negligible high dose hook effects. The correlations between the assays were excellent, but due to standardisat...

journal_title：Annals of clinical biochemistry

authors： Bonte HA,Vermes I,v d Sluijs Veer G

更新日期：1989-11-01 00:00:00

abstract：BACKGROUND:In humans, leptin circulates in a free form and is also bound to macromolecules. The aim of the present study was to compare a rapid acid-ethanol precipitation (AEP) method of measuring bound leptin with the more laborious gel exclusion chromatography (GEC) reference procedure. Serum samples collected from h...

journal_title：Annals of clinical biochemistry

authors： Jamieson NB,McMillan DC,Brown DJ,Wallace AM

更新日期：2003-03-01 00:00:00

abstract：:Homocysteine, a sulphur amino acid, is a branch-point intermediate of methionine metabolism. It can be degraded in the transsulphuration pathway to cystathionine, or remethylated to methionine via the remethylation pathway. In both pathways, major genetic defects that cause enzyme deficiencies are associated with very...

journal_title：Annals of clinical biochemistry

authors： Lievers KJ,Kluijtmans LA,Blom HJ

更新日期：2003-01-01 00:00:00

abstract：:Hypoglycaemia is an uncommon manifestation of hypopituitarism in non-diabetic adults. A 47-year-old woman with Cushing's disease was treated with bilateral adrenalectomy and pituitary radiotherapy following unsuccessful trans-sphenoidal surgery. Twenty years later, she presented with a tonic-clonic seizure and recurre...

journal_title：Annals of clinical biochemistry

authors： McAulay V,Seckl JR,Strachan MW

更新日期：2005-01-01 00:00:00

abstract：:We investigated the contributions made by the entero-insular axis, proinsulin and the fractional hepatic extraction of insulin to the hyperinsulinaemia characteristic of polycystic ovarian syndrome (PCOS). We measured plasma glucose, gastric inhibitory polypeptide (GIP), glucagon-like peptide-1 (7-36 amide) (GLP-1(7-3...

journal_title：Annals of clinical biochemistry

authors： Gama R,Norris F,Wright J,Morgan L,Hampton S,Watkins S,Marks V

更新日期：1996-05-01 00:00:00

abstract：:We have made an evaluation of glycosylated haemoglobin measurements by affinity chromatography in a paediatric population. Age-related reference values for non-diabetic infants and children are reported. A poor correlation (r = 0.24) was found between glycosylated haemoglobin values in 26 insulin-dependent diabetic ch...

journal_title：Annals of clinical biochemistry

authors： van Heyningen C,Hanid TK,Hopkinson I

更新日期：1986-07-01 00:00:00

abstract：:A total of 1381 urine specimens were screened using a Microgenics CEDIA urinary primary methadone metabolite (2-ethylidene-1,5-dimethyl-3,3-diphenylpyrrolidine; EDDP) immunoassay (cut-off calibrator concentration of 100 microg/L) in combination with a Dade Behring EMIT urinary methadone immunoassay (cut-off calibrator...

journal_title：Annals of clinical biochemistry

authors： George S,Parmar S,Meadway C,Braithwaite RA

更新日期：2000-05-01 00:00:00

abstract：:Some inherited metabolic disorders (IMDs) can cause significant complications during pregnancy, affecting the mother and/or the fetus. Although it appears that only a minority of IMDs have these effects, experience is still being acquired. For some disorders, patients will not have reached child-bearing age. Pregnanci...

journal_title：Annals of clinical biochemistry

authors： Preece MA,Green A

更新日期：2002-09-01 00:00:00

abstract：BACKGROUND:Angiogenesis is involved in the pathogenesis of diabetic retinopathy. Osteoprotegerin, a recently identified glycoprotein belonging to the tumour necrosis factor receptor superfamily, has been implicated to be correlated with angiogenesis. This study aims to determine whether serum and vitreous concentration...

journal_title：Annals of clinical biochemistry

authors： Yu G,Ji X,Jin J,Bu S

更新日期：2015-03-01 00:00:00

abstract：:A simultaneous deterioration in performance of several radioimmunoassays suggested that equipment was malfunctioning. Replicate counts from an automated gamma counter showed unacceptable variation during a 24-hour period; this variation was detected using Trigg's technique, a sensitive method for trend analysis, and w...

journal_title：Annals of clinical biochemistry

authors： Challand GS,Cox L

更新日期：1978-03-01 00:00:00

abstract：:The hypoglycaemia caused by non-islet cell tumours is often associated with an increase in plasma insulin-like activity. In many cases there is a relative if not always absolute increase in plasma insulin-like growth factor II (IGF-II). Growth hormone (GH) secretion is almost invariably depressed as is the plasma insu...

journal_title：Annals of clinical biochemistry

authors： Teale JD,Blum WF,Marks V

更新日期：1992-05-01 00:00:00

abstract：:Mass spectrometry has for many years enabled us to rapidly identify and quantify many different compounds in biological samples. The equipment is currently available in specialist centres investigating metabolic disorders and in toxicology laboratories. Improvements in sample introduction and refinements in the mass s...

journal_title：Annals of clinical biochemistry

authors： Honour JW

更新日期：2003-11-01 00:00:00