The case subject was a 40-year-old male with a compound heterozygous CETP deficiency. Two heterozygous CETP deficient cases and 10 normal volunteers were also recruited as controls. They underwent an oral fat tolerance test (OFTT) and their blood was taken at fasting and during the OFTT to be used for laboratory tests.

The case subject had apolipoprotein E (apo-E) phenotype 4/2 with fatty liver but without any cardiovascular disease. His serum TG, HDL-C, apo-AI and apo-B48 levels were significantly higher, but the low-density lipoprotein cholesterol level was lower than controls. Although post-heparin plasma lipoprotein lipase and hepatic lipase (both mass and activity) were nearly normal, the serum level of angiopoietin-like-protein-3 was extremely elevated. While his serum remnant-like particles-TG (RLP-TG) and total TG levels significantly increased after a fat load, the RLP-cholesterol (RLP-C) level did not increase during OFTT.

The case subject was different from the common CETP deficient cases reported previously. Also, the results indicated that the metabolic pathways of RLP-C and RLP-TG formation in the postprandial state are controlled independently in CETP deficient cases. CETP deficiency itself may not be atherogenic, while one with elevated RLPs may be atherogenic. These cases may have raised the controversy of whether CETP deficiency is atherogenic or not.

H-FABP was measured on redundant routine outpatient samples using the MARKIT-M (Dainippon) and the Evidence Investigator (Randox) assays.

Two hundred and forty-two subjects with Siemens Ultra-TnI value <0.045 µg/L (99th centile) were studied. In all, 174 subjects had estimated glomerular filtration rate (eGFR) >60 mL/min. The 99th centile values for subjects with eGFR >60 mL/min for the Evidence Investigator H-FABP were 5.3 and 5.8 µg/L and for the MARKIT-M H-FABP were 8.3 and 9.1 µg/L in female and male subjects, respectively. There is an increase in H-FABP with age in subjects with normal renal function for both assays. Gender comparison showed no significant difference for either assay. Comparison of samples showed that subjects with eGFR <60 mL/min showed a median increase of 0.71 µg/L with Evidence Investigator assay and 1.09 µg/L with MARKIT-M assay compared with subjects with eGFR >60 mL/min. Calibration differences were confirmed by cross measurement of calibrators and recombinant H-FABP.

We have defined the 99th centile values for H-FABP in a population of primary and secondary care outpatients that can be used to risk stratify patients with ACS. We have confirmed that H-FABP increases with renal dysfunction and age, but have not confirmed the gender difference previously reported.

Eighty-three patients were recruited from a renal outpatient clinic. In a 24 h period, each collected an early-morning urine (EMU), second and third voids, and the remaining urine passed that day. PCR and ACR were determined in random urines and compared with the 24 h loss of protein and albumin, respectively.

For all patients, median (range) 24 h urine protein and albumin losses were 220 (30–15600) and 60 (<8–10,557) mg, respectively. Ratios derived from each of three random urines correlated well with 24 h protein or albumin loss (Spearman's r_s > 0.87, P < 0.0001). Receiver operator characteristic (ROC) curve analysis showed PCR accurately predicted both an abnormal 24 h urine protein ≥150 mg/24 h (areas under curves [AUC] 0.90–0.92) and significant proteinuria above 300 mg/24 h (AUC between 0.97 and 1.00). ACR accurately predicted both an abnormal 24 h urine albumin ≥30 mg/24 h (AUC 0.98 to 0.99) and frank albuminuria at ≥300 mg/24 h or ≥700 mg/24 h (AUC between 0.99 and 1.00). EMU and random urines performed equally well in predicting proteinuria and albuminuria from PCR and ACR, respectively.

By careful choice of cut-offs, both PCR and ACR can be used in patients with kidney disease to rule in or rule out abnormal 24 h losses of protein and albumin. EMU and, importantly, random samples can be used as surrogates for 24 h urine collections.

Levels of ACT and PSA–ACT were determined by sandwich enzyme-linked immunosorbent assay in CSF and serum samples of AD (n = 16), frontotemporal lobe dementia (FTLD) (n = 19), mild cognitively impaired (MCI) patients (n = 19) and controls (n = 12). Total PSA was determined in a non-competitive immunoassay. Reverse transcriptase–polymerase chain reaction (RT–PCR) for PSA was performed on postmortem hippocampus and temporal cortex specimens from control and AD cases.

PSA is expressed in the brain, as detected by RT–PCR. PSA and PSA–ACT complexes were detectable in CSF of almost all male and only very few female subjects. The levels of PSA and PSA–ACT complexes in CSF did not differ between AD, FTLD, MCI and control groups. PSA CSF/serum quotients highly correlated with albumin CSF/serum quotients. Furthermore, the hydrodynamic radius of PSA was found to be 3 nm and the theoretical PSA quotient, derived from the Felgenhauer plot, corresponded well with the measured PSA quotient.

PSA is locally produced in the human brain; however, brain PSA hardly contributes to the CSF levels of PSA. PSA and PSA–ACT levels in CSF are not suitable as a biomarker for AD.

Twenty-four-hour urine samples were collected from 133 patients into bottles without acid or preservatives. In a subset of 29 patients, 10 mL aliquots were prepared to test the effect on urine calcium of 0.1, 1.0 and 5.0 mol/L hydrochloric acid (HCl). Calcium was then measured immediately after acidification, after 12 h and seven days storage at 4°C. In a separate study, urine calcium concentrations in paired control (non-acidified) and acidified (with 5 mol/L HCl) samples were compared in 133 patients. When available, we recorded the time from start of urine collection to time of analysis. Calcium was measured using the cresolphthalein complexone colorimetric endpoint assay on the Roche Modular system.

There was no significant difference in the calcium concentration in the 29 cases studied between the varying acid concentrations tested compared with non-acidified urine (P = 0.987). Overall, in 133 patients there was no difference between control and acidified samples (P = 0.888). We found no correlation between basal urine pH and urine calcium at all time points studied.

Our results suggest that the acidification of urine samples is not a preanalytical necessity for the measurement of urine calcium.

Using the commercial fluorescent SYBR^® Gold stain, biological fluids were directly assayed for CFD without prior DNA extraction and amplification. Stain was added to the sample in 96-well plates (final stain dilution: 1:10,000) and fluorescence was read by a fluorometer (excitation wavelength 488 nm, emission wavelength 535 nm).

The assay was validated with serum, whole blood, urine and supernatant of cell cultures. Specificity and linearity were demonstrated over a wide range of concentrations; the results correlated with the conventional quantitative polymerase chain reaction assay of β-globin (R² = 0.9987, P < 0.001). The assay was not affected by exposure of whole blood or serum to room temperature for four or 24 h, respectively. Intra and day-to-day coefficients of variation (16–4.8% and 31–8%, respectively; depending on DNA level) compared well with published data describing more work-intensive tests. The limit of quantitation (170 ng/mL) was below the mean DNA level in a cohort of normal individuals (471 [203] ng/mL). Finally, free DNA in supernatant of cell cultures after cell lysis accurately reflected cell number (R² = 0.974, P < 0.0001).

The direct SYBR^® Gold assay proved to be an accurate and simple technique for measuring CFD in biological fluids.

Blood samples were collected from 61 CABG patients at different time points. Using ⁵¹Cr-ethylenediaminetetraacetic acid (⁵¹Cr-EDTA) clearance as a ‘gold standard’, we compared the correlations and non-parametric receiver operator characteristic curves of serum cystatin C, serum creatinine and 24 h creatinine clearance (Ccr).

The inverse of cystatin C correlated better with ⁵¹Cr-EDTA than those of serum creatinine and Ccr (r = 0.8578, 0.6771 and 0.6929, respectively). Cystatin C exhibited significantly superior diagnostic accuracy for detecting GFR <80 mL/min/1.73 m² compared with serum creatinine (P = 0.013) and Ccr (P = 0.025); for detecting GFR <60 mL/min/1.73 m², cystatin C had similar diagnostic accuracy to Ccr (P = 0.812) but was superior to creatinine (P = 0.033). At the best cut-off value, cystatin C had sensitivity 89% and specificity 93% for detecting GFR <80 mL/min/1.73 m², sensitivity 86% and specificity 96% for detecting GFR <60 mL/min/1.73 m².

Cystatin C is a better marker for detecting small temporary changes of GFR in CABG patients. This may allow better identification of patients with renal impairment.

Four hundreds and sixty-four hyperprolactinaemic samples were collected from the laboratory information system for Saint James University Hospital over a three-year period. These samples were screened for MPRL using PEG precipitation protocol. Monomeric prolactin concentration post-PEG precipitation was compared with a reference range determined by PEG precipitation in normal subjects.

MPRL was the cause of hyperprolactinaemia in 4% of patients (16/409) over the three-year period studied. Nine subjects with MPRL also had elevated monomeric prolactin.

PEG screening is still needed for assays with low MPRL reactivity such as the Advia Centaur and this should be performed with a locally derived reference range for monomeric prolactin.

SST was done on 26 patients with liver impairment. Total cortisol was measured on Advia Centaur; serum CBG by radioimmunoassay and FCI calculated.

Eleven (42%) patients had a total cortisol >550 nmol/L (range 555–2070) and FCI > 12 (12.0–68.9) suggesting sufficient cortisol reserve. Three patients (13%) had total cortisol <550 nmol/L (268–413) and FCI < 12 (3.5–11.6) consistent with cortisol deficiency. Twelve patients (46%) had a total cortisol <550 nmol/L (144–529), but an FCI > 12 (12.0–52.9). None of the patients had a total cortisol >550 nmol/L and FCI < 12.

When total cortisol alone is used to interpret SST in patients with liver impairment, 46% may have been classified as having adrenal insufficiency because of low CBG. FCI may be better for the evaluation of HPA axis insufficiency in patients with liver impairment.

An enzyme-linked immunosorbent assay (ELISA) method was developed using microwell plates coated with intact particles of recombinant AAV-2 vectors, and horseradish peroxidase-conjugated anti-human immunoglobulin G (HRP-IgG). Neutralizing antibody titres were analysed by assessing the ability of serum antibody to inhibit transduction into HEK293 cells of AAV vectors that express β-galactosidase.

Anti-AAV-2 antibodies were detected by ELISA in two of 20 healthy subjects. The positivity criterion (optical density >0.5) in ELISA corresponded to the cut-off value (320-fold dilution of serum) in the AAV-2 neutralization assay. Influences of interfering substances were not observed.

This ELISA method may be useful for rapid screening of anti-AAV-2 neutralizing antibodies in candidates for gene therapy.

Within a healthy paediatric population (n = 246), fetuin-A serum concentrations were determined (ELISA kit; Epitope Diagnostics, San Diego, CA, USA) essentially as described by the manufacturer. At the same time, serum protein and serum albumin were measured with established procedures (Beckman Coulter Inc., Krefeld, Germany). Subjects were stratified according to age (<1 yr [n = 25], ≥1 and <6 yr [n = 65], ≥6 and <12 yr [n = 66], ≥12 yr and <16 [n = 45] and ≥16 yr [n = 45]), and both genders were equally distributed within each age cohort.

Within each age cohort, fetuin-A serum concentrations were normally distributed, independent of age and gender and the respective reference range (mean ± 1.96 SD) is 0.22–0.70 g/L (0.46 ± 0.24 g/L).

Fetuin-A serum concentrations are independent of age and gender in a healthy paediatric population and are well comparable with those determined in adults with the same assay.

Lipoprotein fractions were generated using a self-generating iodixanol gradient. AG and UAG were measured using specific enzyme immunoassays.

AG bound to all lipoproteins in approximately equal concentrations (VLDL 26%, LDL 22%, HDL 23%) and was present as a plasma protein (27%). UAG bound more specifically to HDL (49%) and was present as a plasma protein (48%).

The different binding patterns of AG and UAG may have significant implications for their biological effects, including roles in energy metabolism, the development of obesity and potentially in the modulation of cardiovascular disease.

A formula for CD is developed, which specifies that even with the assumption of constant coefficient of variations (CV) at the two measurement concentrations used in the calculation, there will be different SDs due to different concentrations.

The effect of removing the assumption of constant SD is to increase the CD for rises in analyte concentration and to decrease the CD for falls in concentration. These effects are caused by increased SD for the second measurement compared with the first when the second measurement is higher, and the reverse when the second is lower.

Replacing the usual assumption of similar total result SD for both measurements included in the CD calculation with a calculation of the SD at both analyte concentrations leads to an increase in the magnitude of the CD for rises in analyte concentration and a decrease for falls in analyte concentration. This change is proposed for all forms of CD calculations.

Subjects consisted of 82 patients with CLD. Various indicators for hepatic function as well as HbA_1C and GA were also measured. Estimated HbA_1C values were calculated from the mean plasma glucose levels. Two hundred and two type 2 diabetic patients without CLD were studied as controls.

Although GA was strongly correlated with HbA_1C in patients with CLD as well as diabetic patients, GA levels in patients with CLD were relatively higher than those in diabetic patients. In patients with estimated HbA_1C ≤5.8%, GA levels significantly increased but HbA_1C levels decreased as a function of decreasing hepaplastin test (HPT). The ratio of GA/HbA_1C (G/H ratio) increased as a function of decreasing HPT. In patients with estimated HbA_1C >5.8%, in contrast, GA levels were independent of HPT levels. In the patients with CLD, GA and HbA_1C were associated with mean plasma glucose levels and some indicators for hepatic function. The multivariate analysis revealed a significant association of G/H ratio with HPT, cholinesterase and direct bilirubin. The G/H ratio was not associated with the mean plasma glucose but with HPT and cholinesterase levels.

The G/H ratio correlates with hepatic function but not with plasma glucose levels. Therefore, CLD should be suspected for diabetic patients with an elevated G/H ratio.

Imprecision of the four methods were compared by computing total imprecision from within-run and between-run data. A total of 80 samples were also compared and analysed by Deming regression and Altman–Bland difference test.

Study of total imprecision of the in2it at HBA1c levels of 6.0% and 10.4% produced a coefficient of variation (%CV) of 3.8% and 3.7%, respectively. These results were more favourable as compared with the DCA 2000 but did not match the low imprecision of the central laboratory methods, the Bio-Rad Variant II and the Roche cobas c501. Comparison between the in2it and the central laboratory analysers, Bio-Rad variant II and cobas c501, revealed positive bias of 12% and 10%, respectively, supported by corresponding Deming regression equation slopes of +1.18 and +1.14. Comparison between the DCA 2000 and the central laboratory analysers revealed a bias that became increasingly positive with rising HbA1c concentrations with Deming regression analysis also revealing proportional and constant differences.

The in2it is a suitable POCT analyser for HbA1c but its less than ideal precision performance and differences with the central laboratory analysers must be communicated to and noted by the users.

The ‘latent reference values’ of aspartate aminotransferase (AST), alanine aminotransferase (ALT), alkaline phosphatase (ALP), gamma-glutamyltransferase (GT), cholinesterase (ChE) and total bilirubin (T-Bil) were extracted from a seven-year database of outpatients (aged 20–79 yr; comprising approximately 1,270,000 test results). After calculating the monthly means for each variable, the time-series data were separated into trend and seasonal components using a local regression model (Loess method). Then, a cosine function model (cosinor method) was applied to the seasonal component to determine the periodicity and fluctuation range. A two-year outpatient database (215,000 results) from another hospital was also analysed to confirm the reproducibility of these methods.

The serum levels of test results tended to increase in the winter. The increase in AST and ALT was about 6% in men and women, and was greater than that in ChE, ALP (in men and women) and GT (in men). In contrast, T-Bil increased by 3.6% (men) and 5.0% (women) in the summer. The total protein and albumin concentrations did not change significantly. AST and ALT showed similar seasonal variation in both institutions in the comparative analysis.

The liver function tests were observed to show seasonal variations. These seasonal variations should therefore be taken into consideration when establishing either reference intervals or cut-off values, which are especially important regarding aminotransferases.

Individuals’ anthropometric measurements, including weight, height, and waist and hip circumferences, were measured and the percent of body fat (BF%) was also obtained. Blood sampling was done in order to determine lipid profile, including total cholesterol (TC), triglycerides (TG), low-density lipoprotein cholesterol (LDL-C), high-density lipoprotein cholesterol (HDL-C), lipoprotein a (Lp(a)) and fasting blood sugar (FBS) concentrations. Systolic and diastolic blood pressures (SBP and DBP) were also measured.

The mean ages of firefighters and administrative staff were 42.45 ± 6.75 and 44.64 ± 5.83 y, respectively. The prevalence of overweight and obesity was 45% and 24% in firefighters and 54% and 23% in administrative staff, respectively. High waist-to-hip and waist-to-stature ratios were detected in 26.4% and 81.3% of firefighters versus 33.3% and 89.7% of the control group, respectively. No significant differences were observed between the mean of TC, TG, HDL-C, LDL-C and FBS concentrations. The mean of Lp(a) was significantly higher among firefighters (P<0.05). About half of the subjects in both groups had TC >5.17, TG >1.69, HDL-C <1.03 nmol/L and Lp(a) >25 mg/dL. There were no significant differences between the SBP and DBP of subjects. There was no significant difference in smoking habits between the two groups.

Considering the high prevalence of overweight and obesity, high TC, TG and Lp(a) and low HDL-C concentrations among all firefighters, it seems necessary to provide fitness-promotion and nutritional education programs for the prevention of obesity-related chronic diseases such as CVD.

To evaluate indications, outcomes and confounding factors of OGTTs performed at a large teaching hospital and to compare them with Australian DM guidelines.

A retrospective audit of OGTTs performed over an 18-month period in a teaching hospital in a major Australian city. Information gathered included co-morbidities; medications; risk factors for type 2 DM; indication for OGTT; results of OGTT and previous glucose tests.

All 129 OGTTs identified were included in the audit. Eighty-nine (69%) were male, with a median age of 57 years (range 19–86), and 3% were of Australian Aboriginal ethnicity. An indication for OGTT was identified in 93%, including FPG 5.5–6.9 mmol/L (36%) and random plasma glucose (RPG) 5.5–11.0 mmol/L (19%). Other indications for OGTT identified included polycystic ovary syndrome or metabolic syndrome (8%), peripheral neuropathy (3%) and as part of a research protocol (12%). Forty-two (35%) were inpatients at the time of OGTT, of which 35 (30%) were admitted for acute medical or surgical illnesses such as stroke. Nineteen percent were taking medications known to affect plasma glucose (e.g. oral corticosteroids).

Only 55% of OGTTs had a previous FPG or RPG value warranting OGTT using current Australian DM guidelines. Other valid indications for OGTT were identified in the majority of the remainder. In addition, 41% were performed in the presence of confounding factors (such as acute illness or medications known to affect plasma glucose). Many of the OGTTs that are currently being performed are in the presence of confounding factors that could cause misleading results.

Superoxide anion radical (O₂^.–) generation and the levels of malondialdehyde (MDA) served as an index of lipid peroxidation along with the analyses of activities of superoxide dismutase (SOD), glutathione peroxidase (GPx) and glutathione reductase (GRx); also, glutathione status, including reduced glutathione (GSH) and oxidized glutathione (GSSG), and the levels of vitamins A, C and E were determined.

In 54 patients, the levels of O₂^.–, MDA and GSSG, and the activities of SOD and GRx of blood were significantly higher than those of 57 controls. Conversely, the levels of GSH and total GSH, and GSH/GSSG ratio, and vitamins A and C were significantly decreased. Additionally, there were no significant changes in the activity of GPx and the levels of vitamin E.

Our data suggest that the redox statuses in patients with HBV-associated HCC were elevated or decreased in certain parameters. However, the increased activities of antioxidant enzymes may be a compensatory up-regulation and the decrease antioxidant statuses were responses to the enhanced oxidative stress in those patients.

Whole unstimulated resting saliva was collected to determine sample stability (temperature, time, effect of a protease inhibitor), limit of quantitation (LOQ), assay precision and analytical variation. The reference range for 134 healthy adults was determined.

Linearity was excellent (4–10.3 mg L^–1, P < 0.001; R² = 0.997) and without significant bias (mean of –0.7%). The lowest intra- and inter-analytical coefficients of variation were 1.8% and 7.5% and LOQ was 1.4 mg L^–1. The concentration of s-IgA is stable at room temperature for up to 6 h, at 4°C for 48 h, at –4°C for two weeks and at –80°C for up to 1.3 yr. There is no evidence that a protease inhibitor increases the stability or that repeated freeze–thawing cycles degrade sample quality. The reference ranges for s-IgA concentration, s-IgA secretion, s-IgA:albumin and s-IgA:osmolality were 15.9–414.5 mg L^–1, 7.2–234.9 µg min^–1, 0.4–19 and 0.6–8.9, respectively.

Automated PENIA assay of s-IgA is precise and accurate. High stability of collected saliva samples and the ease and speed of the assay make this an ideal method for use in athletic and military training situations. The convenience of measuring albumin and IgA on the same analytical platform adds to the practicability of the test.

Data from 890 consecutive sFLC requests were retrospectively analysed. These included 549 samples for serum electrophoresis (sEPG), 447 for sIFE, and 318 for uEPG and urine immunofixation (uIFE). A total of 219 samples had sFLC, sEPG, sIFE and uEPG + uIFE performed. The ability of different test combinations to detect the presence of monoclonal proteins was compared.

The sFLC / ratio (FLC ratio) indicated monoclonal light chains in 12% more samples than uEPG + uIFE. The combination of sEPG and FLC ratio detected monoclonal proteins in 49% more samples than the combination of sEPG and sIFE. Furthermore, the sEPG + FLC ratio combination detected monoclonal protein in 6% more samples than were detected by the combined performance of sEPG, sIFE, uEPG and uIFE. However, non-linearity of the assay, the expense of repeat determinations due to the narrow measuring ranges, and frequent antigen excess checks were found to be limitations of the sFLC assay in this study.

The FLC ratio is a more sensitive method than uIFE in the detection of monoclonal light chains and may substantially reduce the need for onerous 24 h urine collections. Our proposed algorithm for the evaluation of monoclonal gammopathy incorporates the sFLC assay, resulting in a reduction in the performance of labour intensive sIFE and uEPG + uIFE while still increasing the detection of monoclonal proteins.

An internal quality control (QC) program was developed as part of a quality management framework for the trial. PoCT device operators were provided with a colour-coded QC Result Sheet and QC Action Sheet for on-site recording and interpreting of their results. Within-practice imprecision for QC testing was calculated and compared with the analytical goals for imprecision set prior to the trial.

The average participation rate for QC testing was 91% or greater. Median within-practice imprecision met the analytical goals for all PoC tests, except for high-density lipoprotein-cholesterol (HDL-C) where observed performance was outside the minimum goal for one level and one lot number of QC. Most practices achieved the imprecision goals for all analytes, with the principal exception of HDL-C.

Results from QC testing indicate that PoCT in the GP trial met the analytical goals set for the trial, with the exception of HDL-C.

Thirty-two ESRD patients were followed for six months, during which cTn concentrations were assessed every two months. Baseline biomarker concentrations were compared with those in a simultaneously measured reference population of 501 healthy subjects.

During follow-up 26 (81%), 32 (100%) and 9 (28%) of the patients showed elevated cTn concentrations according to the current cTnT, the hs-cTnT and the cTnI assays, respectively. The range of concentrations measured in each patient had a median (interquartile range) magnitude of 0.03 µg/L (0.02–0.06), 0.017 µg/L (0.011–0.029) and 0.011 µg/L (0–0.017) according to the aforementioned assays.

According to the hs-cTnT assay, all of the ESRD patients had elevated cTnT concentrations at least once during the follow-up. As elevated cTn concentrations are highly prognostic of adverse events, the use of serial measurements has thus identified additional patients at risk for such events. The fact that we find cTn concentrations to be higher in patients with a history of cardiac disease is in line with this. Additional studies in ESRD patients are needed to investigate the added diagnostic and prognostic value of the very low cTnT concentrations and variations detected only by the hs-cTnT assay.

Serial cardiac troponin T (cTnT) was assayed five times over 12 months in a prospective cohort study of patients with end-stage kidney disease treated with haemodialysis. A concentration of cTnT ≥0.04 µg/L was considered increased. Mortality and cardiovascular events were analysed by survival analysis, according to the serial troponin results.

From 100 patients who provided a baseline sample for cTnT, 81 completed five serial measurements. The analysis of patients who completed serial cTnT measurements demonstrated that 28 patients (35%) had normal cTnT concentrations in all five samples, 20 patients (24%) had between one and four increased cTnT measurements and 33 patients (41%) had increased concentrations of cTnT in all five samples. The 1.7-y patient survival was 100%, 90% and 78% for patients with zero, one to four, or five out of five concentrations of cTnT increased, respectively (P = 0.037), and the corresponding cardiovascular event-free survival was 100%, 91% and 78%, respectively (P = 0.027).

Serial measurements of cTnT concentration were frequently increased in patients receiving haemodialysis. The number of abnormal measurements over time predicted mortality and cardiovascular adverse events.

Characteristics were studied in optimized conditions measuring wavelength by absorption spectra analysis, and interference of protein and metals with Mg²⁺, Fe²⁺, Cu²⁺ and Zn²⁺. The method was applied to an automated analyser (7170; Hitachi High Technologies Corp). The measurement performance was evaluated for accuracy, precision, recovery rate, linearity and reagent stability with a comparison study against atomic absorption spectrophotometry (AAS).

The within-run and between-run variations (coefficient of variation [CV]) were 0.92–1.01% and 0.75–1.43%, respectively. The linearity was 0–7.0 mmol/L. The comparison study obtained y = 1.002x (AAS) – 0.10, Sy/x = 0.18 mmol/L, n = 50. Reagent stability was at least 20 d at 4°C without daily calibration.

The new calcium measurement method in serum was demonstrated to have reliable and acceptable performances as a routine test in clinical laboratory.

Capillary blood samples were taken from 100 patients attending a diabetes centre and blood glucose measured on Roche Performa (n = 4) and Medisense Optium Xceed 5 s (n = 2) and 10 s reading (n = 2) meters. Venous plasma glucose from samples taken simultaneously was measured by the laboratory hexokinase method as reference standard. Imprecision was determined on the meters by replicate analysis (n = 20) of control solutions provided by the manufacturers and also patient venous whole-blood samples. Accuracy was assessed relative to the reference method by Bland–Altman plots, Passing and Bablok regression analysis, and both Clarke and consensus error grid analysis. Coefficients of variation (CVs) were calculated to determine imprecision.

Bland–Altman and Passing–Bablok analysis confirmed significant systematic bias for all meters, with relative under-reading of higher glucose concentrations. Error grid analysis showed that <5% readings exceeded ±20% (or ±0.83 mmol/L for readings <4 mmol/L) deviation from the reference method (1%, 2% and 4% for the Roche, Optium 5 and 10 s meters, respectively). CVs were all <4% for the control solutions and <6% for patient samples.

Both Roche Performa and Medisense Optium glucose meters (5 and 10 s readings) perform satisfactorily and are acceptable for operational use.

Samples were analysed by two-dimensional gel electrophoresis and significantly differentiated proteins were identified by nano-LC-ESI-MS.

A total of 12 protein signatures that were differentially displayed with high significance compared with controls were selected. Four of the differentially displayed proteins were identified as haptoglobin alpha2, haptoglobin Hp2(fragment) and transthyretin and Chain A (formerly prealbumin), and all were up-regulated. Thiol-specific antioxidant protein, Chain A, tertiary structures of three amyloidogenic transthretin variants and haptoglobin-related protein precursor were all down-regulated in controls with a family history of diabetes, early and late diabetic patients in comparison with the control.

A proteomic-based approach was used to discover and identify the differentially expressed proteins in various states of type 2 diabetes.

Thirty-six laboratories each assayed 20 samples (the same 20 in each laboratory) using two different Lp(a) kits per laboratory, randomly assigned from the total of 12 used in the study.

The duplicate error, i.e. the error between-duplicate analyses for each sample, for all kits was small, indicating all kits had a good precision for all the assays. However, there was a very large variation between the kits in the Lp(a) concentration assigned to a sample that could be over 100%. All methods showed a negative or positive bias as the concentration of Lp(a) increased. Most worryingly, as used in this study, several Lp(a) kits detected Lp(a) in a solution of 5% bovine serum albumin in phosphate-buffered saline. The between-laboratory variation in Lp(a) concentration measured using the same kit was very large, e.g. for a sample with a mean concentration of 78.8 mg/dL Lp(a) the between-laboratory variation was 29.7 mg/dL (37.7%). Even with samples with a relatively low Lp(a) concentration of 16.0 mg/dL had a between-laboratory variation of 12.3 mg/dL (76.8%).

There is wide variability in reported Lp(a) concentrations, assayed in the same sample, using different Lp(a) assays. At the present time these differences prevent the use of Lp(a) as a routine diagnostic tool.

Forty-four laboratories located in health-care institutions with inpatient beds were surveyed about the organizational, clinical and methodological aspects of tumour markers ordering.

Thirty-one laboratories (70%) filled in and returned the questionnaire. Overall, 977,786 tumour marker tests were scrutinized. The pattern of tumour marker use did not seem to be influenced by the institutional setting, by availability of oncology facilities or by adoption of clinical guidelines. In addition, the information flow from clinicians to the laboratory and vice versa was poor and informal.

Monitoring tumour marker pattern use can provide valuable information for health-care decision makers, highlighting potential inadequacies in laboratory services but also identifying problems in other areas of health-care delivery that could benefit from educational programmes.

Copper and zinc were measured in 48 serum samples using the Randox colorimetric copper (CU2340) and zinc (ZN2341) assays on the Data Pro analyser and the results compared with those from a Varian Spectra 880 atomic absorption spectrometer. A smaller set of samples (n = 15) were also analysed colorimetrically for zinc on the Roche Cobas Mira.

Linear regression analyses of Bland and Altman plots from the Data Pro – AAS comparison gave the following results for copper: correlation r = 0.6669 (P < 0.01), slope = –0.2499 (P < 0.01), intercept = 3.219 (P < 0.01). For zinc, results were as follows: correlation r = 0.1976, slope = 0.1807, intercept = –1.922. For the smaller set of samples, the Cobas Mira – AAS comparison for zinc gave correlation r = 0.4379, slope = 0.5294, intercept = –4.074. The results indicated significant systematic and fixed bias between the colorimetric copper and the AAS method.

Performances in comparison to AAS methods indicated the colorimetric methods, as used, are unsuitable for the accurate determination of copper and zinc in human serum.

Twenty-one consecutive patients (17 men and 4 women) undergoing single-vessel percutaneous coronary angioplasty were enrolled in the study. IMA and albumin levels were measured together with myoglobin, creatine kinase 2 and cardiac troponin I, before (Group 1), immediately after (Group 2) and 6 h after (Group 3) the procedure of PCI.

The IMA levels of Group 2 were significantly higher than those of Group 1 and Group 3 (P < 0.05 for both). However, correction of IMA by multiplying with the (individual albumin concentration of the patient/median albumin concentration of Group 1) ratio gave no statistical differences between the groups (P > 0.05). There were strong negative correlations between IMA levels and albumin concentrations within individual groups (r = –0.757, P < 0.001; r = –0.712, P < 0.001; and r = –0.705, P < 0.001 for Group 1, Group 2 and Group 3, respectively).

The results confirm the close dependency of IMA results on albumin concentrations. Therefore, IMA results reflect albumin concentrations rather than myocardial ischaemia also in PCI. This situation and lack of standard reference materials for the albumin cobalt binding assay can lessen the diagnostic performance of IMA.

A detailed questionnaire covering most aspects of sweat collection and analysis was sent to all participating laboratories in 2007.

Twenty out of 38 laboratories completed the questionnaire. While adherence to accepted guidelines was noted in many areas, the following main variations were recorded: some laboratories were not doing enough sweat tests to maintain expertise; some were not collecting sweat for the recommended collection time; sweat conductivity was the only test available in some laboratories; there was a lack of agreement between the sweat chloride concentration used to indicate CF or define an equivocal result.

There is room for improvement in the performance of the sweat test in some laboratories in Australasia. The Sweat Testing Working Party of the Australasian Association of Clinical Biochemists is the appropriate body to address the problems involved in sweat testing and to bring about change.

Currently, two intact FGF-23 assays (Kainos; Immutopics) and one C-terminal FGF-23 assay (Immutopics) are available. We determined intra- and inter-assay variation, linearity and matrix interference in these assays. Moreover, we compared assay results from healthy subjects with those of patient groups with expected high FGF-23 concentrations.

Intra-assay variation was reasonably good in all three assays. Inter-assay variation and linearity were poor for the intact Immutopics assay but reasonable for both other assays. Immutopics assays gave best results in ethylenediaminetetraacetic acid (EDTA) plasma, while the Kainos assay showed comparable reproducibility in EDTA plasma and serum. Although the manual of the Kainos assay states that an automatic washing machine can be used, acceptable results were only found by manual washing. Patients with kidney disease and patients with hypophosphatemic osteomalacia had increased C-terminal FGF-23 concentrations compared with healthy controls.

Two assays of reasonable quality are available for FGF-23, the intact FGF-23 assay (Kainos) provided proper attention is paid to the washing procedure, and the C-terminal assay (Immutopics).

Twelve PCOS, 11 matched healthy women; 12 postmenopausal diet-controlled T2DM and 11 matched healthy postmenopausal women were recruited. Blood samples were collected at 4-d intervals on 10 consecutive occasions. The biological variability of IR was derived on duplicate samples.

Mean and biological variability of HOMA-IR for PCOS did not differ from T2DM. Both measures were higher than the matched controls. There was no difference in insulin or IR measures between the body mass index matched pre- and postmenopausal women. Percentage β cell function were 208.8%, 62.3%, 106.5% and 111.9%, respectively, in PCOS, postmenopausal women with T2DM, healthy premenopausal and healthy postmenopausal women.

The progression from PCOS to the development of T2DM is unlikely to be due to a further increase in IR (or variability), but rather the progressive failure of pancreatic beta cells with a decrease in insulin production.

The clinical trial registration number for this study is ISRCTN65353256.

Laboratory staff inspected samples for haemolysis and their observations were compared with the measured HI. The potassium concentrations and haemolytic indices of 613 adult and 523 neonatal samples were correlated to derive equations to compensate for the increase in potassium with increase in HI. These were found not to differ significantly and a single equation for use in both populations was derived.

The presence of icterus was found to decrease ability to detect haemolysis on inspection. The mean (95% confidence limits) potassium increase per unit HI was 0.0094 mmol/L (0.0078–0.0103 mmol/L) for adults and 0.0108 mmol/L (0.0094–0.0121 mmol/L) for neonates. The equation developed to compensate for potassium release in haemolysed samples was: adjusted potassium = measured potassium – (HI in µmol/L x 0.01).

The use of HI rather than visual inspection is particularly recommended in neonates whose serum tends to be icteric. It can be used in the same correction equation as in adults to compensate for potassium released due to haemolysis and facilitate reporting a qualitative comment to assist in immediate clinical management.

Internal standard (hexadeuterated 25-hydroxyvitamin D₃) was added to serum or plasma followed by protein precipitation with methanol. Following centrifugation, a robotic instrument (CTC PAL [Presearch] for ITSP^TM SPE [MicroLiter Analytical Supplies, Inc]) performed a six-step SPE procedure and the purified samples were injected into the LC-MS/MS. Quantification of 25OHD₃ and 25OHD₂ was by electrospray ionization MS/MS in the multiple-reaction monitoring mode.

The lower limit of quantitation was 4.0 nmol/L for 25OHD₃ and 7.5 nmol/L for 25OHD₂. Within- and between-assay precision was below 10% over the concentration range of 22.5–120 nmol/L for D₃ and 17.5–70 nmol/L for D₂ (n = 10). The calibration was linear up to 2500 nmol/L (r = 0.99). Recoveries ranged between 89% and 104% for both metabolites and no ion suppression was observed. The results obtained compared well (r = 0.96) with the IDS-OCTEIA 25-hydroxyvitamin D enzyme immunoassay for samples containing less than 125 nmol/L, at higher concentrations the immunodiagnostic system (IDS) method showed positive bias.

Our simplified sample preparation and automated SPE method is suitable for the measurement of 25OHD₃ and D₂ in a routine laboratory environment. The system can process up to 300 samples per day with no cumbersome solvent evaporation step and minimal operator intervention.

In this controlled study, women were assigned to an intervention group (n = 13) or a control group (n = 14). The total study duration was 20 weeks, during which the subjects had to give blood on nine occasions (week –8 [baseline], –4, 0, 1, 2, 3, 4, 8 and 12) for analyses of serum and erythrocyte folate, and plasma total homocysteine. The intervention group received 500 µg/d FA during the first eight weeks, and discontinued the intake from weeks 0 to 12. No supplements were supplied to the control group.

Serum folate and plasma total homocysteine returned to baseline after 12 weeks of FA discontinuation, erythrocyte folate did not.

An FA/OC combination pill seems to be of value for only a minor portion of women. Active efforts to stimulate women of child-bearing age to take FA remain essential.

Three CSF-pool samples were distributed to 13 laboratories in 2004 and the same samples were again distributed to 18 laboratories in 2008. In 2004 six laboratories measured Aβ_1–42, Tau and P-Tau and seven laboratories measured one or two of these marker(s) by enzyme-linked immunosorbent assays (ELISAs). In 2008, 12 laboratories measured all three markers, three laboratories measured one or two marker(s) by ELISAs and three laboratories measured the markers by Luminex.

In 2004, the ELISA intercentre coefficients of variance (interCV) were 31%, 21% and 13% for Aβ_1–42, Tau and P-Tau, respectively. These were 37%, 16% and 15%, respectively, in 2008. When we restricted the analysis to the Innotest^® (N = 13) for Aβ_1–42, lower interCV were calculated (22%). The centres that participated in both years (N = 9) showed interCVs of 21%, 15% and 9% and intra-centre coefficients (intraCV) of variance of 25%,18% and 7% in 2008.

The highest variability was found for Aβ_1–42. The variabilities for Tau and P-Tau were lower in both years. The centres that participated in both years showed a high intraCV comparable to their interCV, indicating that there is not only a high variation between but also within centres. Besides a uniform standardization of (pre)analytical procedures, the same assay should be used to decrease the inter/intracentre variation.

We studied 42 patients with DCM and an equal number of age-matched normal volunteers. We assessed IMA serum levels with the albumin cobalt binding test.

IMA was 89.9 ± 13.1 (71–117) KU/L in the patient group and 93.9 ± 9.9 (76–122) KU/L in the control group, with no significant difference between the two (P = 0.11). However, IMA differed significantly according to the New York Heart Association classification (P = 0.003) and was negatively correlated with the left ventricular ejection fraction (r = –0.40, P = 0.014).

We conclude that IMA, a marker of ischaemia, does not differ in patients with clinically stable DCM compared with normal subjects, but varies significantly in relation to the severity of the disease.

We performed a prospective study of 353 blood sampling events during February and March 2007. A proforma was used to obtain detailed information of each blood-taking episode. Information from the proforma was linked to the incidence of haemolysis obtained from the hospital computer system.

The incidence of haemolysis among the samples studied was 6.5%. While staff group, method of sampling, tourniquet time and number of attempts at venepuncture were each univariately associated with haemolysis, stepwise logistic regression resulted in a final model which only included tourniquet time (odds ratio for haemolysis if tourniquet time >1 min was 19.5 [95% confidence interval [CI] 5.6–67.4%]).

Tourniquet time of more than a minute is associated with a significant increase in risk of haemolysis. Advice on tourniquet time is included in phlebotomy training within the hospital; hence a campaign of appropriately channelled continuing education on this issue may be successful in reducing the haemolysis rate.

Urine samples (n = 117) were screened for protein using the Bayer Multistix 10SG and read manually. Urinary total protein and creatinine was measured on the Roche P Modular by the benzethonium chloride and kinetic Jaffe methods, respectively. Urinary albumin was measured by immunoturbidimetry on the Roche Cobas Mira.

The relationship between urinary protein and albumin loss was non-linear (P < 0.05). As urinary protein loss increased the percentage of albumin to total protein increased. At the NICE guidance recommended cut-offs for clinical proteinuria (ACR ≥30 mg/mmol and PCR ≥50 mg/mmol) there was one discordant result between ACR and PCR (ACR <30 mg/mmol and PCR >50 mg/mmol). The Bayer Multistix 10SG had a sensitivity and specificity of 97% and 62%, respectively, for the detection of clinical proteinuria compared with ACR.

The proportion of urinary total protein attributable to albumin changes with concentration. There was only one discordant result between ACR and PCR: therefore either ratio may be used for the identification of clinical proteinuria. As a screening test for proteinuria, the Bayer Multistix 10SG had an acceptable sensitivity but poor specificity.