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Aims: Heart failure (HF) is common in geriatric patients. Clinicians face diagnostic challenges primarily due to comorbidity and limited access to echocardiography. The purpose of this study was to identify independent determinants of the presence of HF in geriatric outpatients and to determine the optimal diagnostic strategy. Methods and Results: Geriatric outpatients [mean age 82 (±6) years, 30% men] with suspected HF underwent an extensive standardized diagnostic work-up. An expert consensus panel determined the presence of HF. Heart failure was present in 94 of 206 participants (46%). Male sex [odds ratio (OR) 2.0], age per 10 years (OR 1.6), nocturnal dyspnoea (OR 1.7), absence of wheezing (OR 2.1), loss of appetite (OR 1.7), and lower body mass index (BMI; OR 0.9) were independently associated with the presence of HF: the c-statistic of the model containing these items was 0.75. Of all additional tests, N-terminal pro-B-type natriuretic peptide (NT-proBNP) improved the diagnostic accuracy the most (OR ln NT-proBNP 2.8; c-statistic 0.92). A diagnostic rule, consisting of six clinical variables and NT-proBNP, showed good negative and positive predictive values. Conclusion: Half of geriatric patients suspected of HF actually have HF. Apart from age, gender, and nocturnal dyspnoea, absence of wheezing, loss of appetite, and lower BMI were independently associated with the presence of HF. Symptoms and signs in combination with NT-proBNP reliably identified the presence or absence of HF in the vast majority of patients. Additional diagnostic tests, in particular echocardiography, can be targeted at those in whom the presence of HF remains uncertain and to ascertain the cause of HF. [ABSTRACT FROM AUTHOR]

In this case report we describe a 67-year-old male, admitted to the ICU with pneumonia who unexpectedly developed a fatal coma due to hyperammonaemia. At postmortem the diagnosis late-onset ornithine transcarbamylase deficiency was made. The non-specific clinical presentation, the rapid deterioration and incidentally the fatal outcome all underline the importance of recognition and knowledge of this genetic disorder. Several measures to treat and prevent potentially fatal episodes of hyperammonaemia are available, if only the disorder is recognised in time. In retrospect, several clues to the diagnosis were available in this fatal case, such as voluntary protein avoidance, as well as several male family members who died at a young age of an unknown cause. After his death, two daughters were discovered to be carriers of an OTC gene mutation, as well as his infant grandson. We emphasise the importance of obtaining ammonia levels in all patients with unexplained coma, seizures or cerebral oedema, irrespective of their age, especially in patients in the ICU or in an otherwise catabolic state.

Background: The Roche Elecsys Vitamin D Total competitive protein-binding assay uses recombinant vitamin D binding protein for measuring 25-hydroxyvitamin D (25-OHD), which is different from commonly used antibody assays., Methods: The assay, standardized against LC-MS/MS, was tested at four sites. Evaluation included precision; between-laboratory variability; functional sensitivity; correlation to LC-MS/MS, HPLC, and immunoassays; as well as robustness, traceability, and EQAS performance., Results: Precision testing showed within-run coefficient of variations (CVs) of ≤ 7%, within-laboratory CVs of <9.5%, between-laboratory precision CVs of ≤ 10.1%, and a functional sensitivity below 9.8 nmol/l (at CV 12.9%). The assay showed equivalent 25-OHD levels for matched serum and plasma samples, good reagent lot-to-lot consistency in pooled sera over time, and good agreement with HPLC (relative bias -8.8%). Comparison with LC-MS/MS methods yielded relative biases of -15.4, -13.5, -10.2, and 3.2%. Comparison against immunoassays showed a relative bias of 14.5% (DiaSorin Liaison) and -58.2% (IDS-iSYS). The overall mean results in 2 years DEQAS was 102% of the ALTM. In a certified reference patient panel, the average bias was < 4% for the sum of 25-OHD2 and 25-OHD3., Conclusion: The Elecsys Vitamin D Total assay demonstrated good overall performance and is, according to present standards, very suitable for automated measurement of 25-OHD., (© 2014 The Authors. Journal of Clinical Laboratory Analysis Published by Wiley Periodicals, Inc.)

Importance: Anemia affects most pregnant African women and is predominantly due to iron deficiency, but antenatal iron supplementation has uncertain health benefits and can increase the malaria burden., Objective: To measure the effect of antenatal iron supplementation on maternal Plasmodium infection risk, maternal iron status, and neonatal outcomes., Design, Setting, and Participants: Randomized placebo-controlled trial conducted October 2011 through April 2013 in a malaria endemic area among 470 rural Kenyan women aged 15 to 45 years with singleton pregnancies, gestational age of 13 to 23 weeks, and hemoglobin concentration of 9 g/dL or greater. All women received 5.7 mg iron/day through flour fortification during intervention, and usual intermittent preventive treatment against malaria was given., Interventions: Supervised daily supplementation with 60 mg of elemental iron (as ferrous fumarate, n = 237 women) or placebo (n = 233) from randomization until 1 month postpartum., Main Outcomes and Measures: Primary outcome was maternal Plasmodium infection at birth. Predefined secondary outcomes were birth weight and gestational age at delivery, intrauterine growth, and maternal and infant iron status at 1 month after birth., Results: Among the 470 participating women, 40 women (22 iron, 18 placebo) were lost to follow-up or excluded at birth; 12 mothers were lost to follow-up postpartum (5 iron, 7 placebo). At baseline, 190 of 318 women (59.7%) were iron-deficient. In intention-to-treat analysis, comparison of women who received iron vs placebo, respectively, yielded the following results at birth: Plasmodium infection risk: 50.9% vs 52.1% (crude difference, -1.2%, 95% CI, -11.8% to 9.5%; P = .83); birth weight: 3202 g vs 3053 g (crude difference, 150 g, 95% CI, 56 to 244; P = .002); birth-weight-for-gestational-age z score: 0.52 vs 0.31 (crude difference, 0.21, 95% CI, -0.11 to 0.52; P = .20); and at 1 month after birth: maternal hemoglobin concentration: 12.89 g/dL vs 11.99 g/dL (crude difference, 0.90 g/dL, 95% CI, 0.61 to 1.19; P < .001); geometric mean maternal plasma ferritin concentration: 32.1 µg/L vs 14.4 µg/L (crude difference, 123.4%, 95% CI, 85.5% to 169.1%; P < .001); geometric mean neonatal plasma ferritin concentration: 163.0 µg/L vs 138.7 µg/L (crude difference, 17.5%, 95% CI, 2.4% to 34.8%; P = .02). Serious adverse events were reported for 9 and 12 women who received iron and placebo, respectively. There was no evidence that intervention effects on Plasmodium infection risk were modified by intermittent preventive treatment use., Conclusions and Relevance: Among rural Kenyan women with singleton pregnancies, administration of daily iron supplementation, compared with administration of placebo, resulted in no significant differences in overall maternal Plasmodium infection risk. Iron supplementation led to increased birth weight., Trial Registration: clinicaltrials.gov Identifier: NCT01308112.

Pituitary adenoma is the main cause of hyperprolactinaemia; however, physicians should be aware that the pituitary is not always to blame. There are many other physiological and pathological causes for hyperprolactinaemia, and the contribution of stress, medication and the presence of macroprolactin should not be overlooked. We describe three patients - a 19-year-old female, a 28-year-old female and a 20-year-old male - in whom hyperprolactinaemia was due to medication use, physical stimulation of the nipple and a combination of macroprolactianaemia with a microadenoma, respectively. The first two case reports show that conducting a thorough patient history can prevent unnecessary imaging and laboratory costs. The third case illustrates that macroprolactinaemia and true hyperprolactinaemia may coexist. While early screening for macroprolactinaemia in an asymptomatic patient can save money, finding macroprolactinaemia in a symptomatic patient still warrants further workup.

Bone-targeting therapeutic radiopharmaceuticals are effective agents for treatment of painful bone metastases. Rhenium-188-HEDP is such a therapeutic radiopharmaceutical and has advantages over commercially available alternatives in terms of efficacy, safety and the ability to be produced on-site, allowing rapid treatment upon presentation of patients with pain. Unlike many other radiopharmaceuticals, there are no standardized preparation methods for Rhenium-188-HEDP. It is known, however, that drug composition may not only affect stability of the final drug product, but it may also influence bone affinity and, thus, efficacy. Furthermore, for support of clinical studies with Rhenium-188-HEDP as an investigational medicinal product, preparation of this radiopharmaceutical has to be performed under GMP conditions. To our knowledge, no group has reported on the preparation of Rhenium-188-HEDP under GMP conditions or on stock production of sterile non-radioactive starting materials. We present the production of GMP grade Rhenium-188-HEDP for application of this therapeutic radiopharmaceutical in routine clinical practice and for support of clinical studies. In addition, bio-distribution data of Rhenium-188-HEDP in mice and in patients with bone metastases originating from prostate cancer are presented., (Copyright © 2014 Elsevier B.V. All rights reserved.)

Background: Presence of the 3-epi-25-hydroxyvitamin D3 [3-epi-25(OH)D3] metabolite affects accurate determination of 25(OH)D3 by most routine liquid chromatography-tandem mass spectrometry (LC-MS/MS) methods and to an unknown extent in present immuno- and protein binding assays. We studied 3-epi-25(OH)D3 cross-reactivity in a competitive protein binding (CPB) assay (Roche Elecsys)., Methods: Neonatal samples, containing up to 58% of 3-epi-25(OH)D3 were used for measurement by the CPB assay and by an LC-MS/MS method separating 25(OH)D3 and 3-epi-25(OH)D3. Analytical recovery was also studied by addition of exogenous 3-epi-25(OH)D3., Results: The CPB assay showed approximately 51% cross-reactivity to 3-epi-25(OH)D3 at exogenous addition. In contrast, there was minimal 3-epi-25(OH)D3 recognition by the CPB assay when present as the natural endogenous metabolite., Conclusions: The automated CPB assay displays minimal 3-epi-25(OH)D3 cross-reactivity in samples containing significant concentrations of endogenous 3-epi-25(OH)D3. Exogenous 3-epi-25(OH)D3 added to human serum or plasma seems to behave different from endogenous presence, and caution is warranted when using samples spiked with vitamin D metabolites for testing analytical specificity or external quality assurance in immuno- or protein binding assays.

Carbohydrate-deficient transferrin (CDT) is a generic term that refers to the transferrin glycoforms whose concentration in blood is temporarily increased by sustained alcohol consumption. Due to high clinical specificity, CDT was proposed as a biomarker of heavy alcohol use and has been available for about 20 years. A number of methods have been developed for CDT measurement based on different analytical techniques and principles and without any harmonization or calibration to a reference method. As a consequence, neither the reference limits nor the cut-off values have been similar across assays, hampering understanding of the diagnostic value of CDT and its routine use. This prompted the International Federation of Clinical Chemistry and Laboratory Medicine (IFCC) to initiate a Working Group on Standardization of CDT (WG-CDT). This third publication of the WG-CDT is devoted to testing the commutability of native and disialotransferrin-spiked serum panels as candidate secondary reference materials, in order to prove the harmonization potential of commercial CDT methods. The results showed that assay harmonization reduced the inter-laboratory imprecision in a network of reference laboratories running the HPLC candidate reference method. In the seven commercial methods evaluated in this study, the use of multi-level secondary calibrators of human serum origin significantly reduced the between-method imprecision. Thus, harmonization of CDT measurements by different methods can be achieved using this calibration system, opening the way for a full standardization of commercial methods against a reference method by use of certified reference materials.

Vitamin D has been shown to modulate innate immune responses in vitro and ex vivo; however, human in-vivo data are lacking. At high latitudes, seasonal vitamin D deficiency is common due to alternating ultraviolet (UV)-B radiation exposure. In the present study, we investigated whether levels of 25 hydroxyvitamin D(3) [25(OH)D(3) ] and its active metabolite 1,25 dihydroxyvitamin D(3) [1,25(OH)(2) D(3) ] are subject to seasonal variation and whether plasma levels of these vitamin D metabolites correlate with the in-vivo cytokine response during experimental human endotoxaemia [administration of lipopolysaccharide (LPS) in healthy volunteers]. Plasma levels of 25(OH)D(3) and 1,25(OH)(2) D(3) were determined in samples obtained just prior to administration of an intravenous bolus of 2 ng/kg LPS (derived from Escherichia coli O:113) in 112 healthy male volunteers. In the same subjects, plasma levels of the inflammatory cytokines tumour necrosis factor (TNF)-α, interleukin (IL)-6 and IL-10 were analysed serially after endotoxin administration. Plasma levels of 1,25(OH)(2) D(3) , but not 25(OH)D(3) , were subject to significant seasonal variation, with lower levels in autumn and winter. 25(OH)D(3) and 1,25(OH)(2) D(3) levels did not correlate with plasma cytokine responses. Furthermore, 25(OH)D(3) deficient subjects (< 50 nmol/l) displayed an identical cytokine response compared with sufficient subjects. In conclusion, plasma levels of vitamin D are not correlated with the LPS-induced TNF, IL-6 and IL-10 cytokine response in humans in vivo. These findings question the direct role of vitamin D in modulation of the innate immune response., (© 2012 British Society for Immunology.)

Background: Excessive intake of alcohol is often associated with low or subnormal levels of vitamin D even in the absence of active liver disease. As vitamin D deficiency is a well-recognized cause of myopathy, alcoholic myopathy might be related to vitamin D deficiency. Chronic alcoholic myopathy affects approximately half of chronic alcoholics and is characterized by the insidious development of muscular weakness and wasting. Although alcohol or its metabolites may have a direct toxic effect on muscles, the relationship between alcoholic myopathy and vitamin D deficiency has not been examined extensively., Methods: We reviewed the literature on alcoholic myopathy and hypovitaminosis D myopathy and compared the pathophysiological findings to designate possible mechanisms of vitamin D action in alcohol-related myopathy., Results and Conclusions: Given the strong interdependency of suboptimal levels of vitamin D, phosphate, and magnesium in chronic alcohol abuse, we hypothesize that combined deficiencies interfere with membrane and intracellular metabolic processes in chronic alcohol-related myopathy; however, it is not yet possible to define exact mechanisms of interaction., (Copyright © 2012 by the Research Society on Alcoholism.)

Objectives: Measurement of serum 25-hydroxyvitamin D [25(OH)D] is generally considered to be a reliable indicator of vitamin D status. The recent increase in diversity of 25(OH)D assays prompted us to evaluate the performance of chromatographic methods (two in-house ID-LC-MS/MS and HPLC (ClinRep, Recipe)), a protein binding method (Cobas-25(OH)D-total, Roche) and immunochemical methods (Liaison and RIA (Diasorin), iSYS (IDS), ADVIA Centaur (Siemens), and Architect i1000 and i2000 (Abbott))., Methods: Blood was drawn from randomly selected outpatients (N=60) at one site after informed consent. DEQAS and SRM 972 samples were obtained from the scheme organizer and NIST, respectively. Serum aliquots were prepared, frozen and transported to participating centers. Method comparison was performed according to CLSI-EP9 specifications., Results: With these patient samples, and in comparison with ID-LC-MS/MS, Deming regression parameters slope, intercept and R were found to be within the ranges [0.57-1.07], [-1.7 to 6.9 nmol/L] and [0.88-0.98], respectively. 25(OH)D2 in DEQAS and SRM samples was fully recognized by chromatographic methods, but only partially by protein binding and immunochemical methods. Chromatographic methods, and to a lesser extent the protein binding assay, showed cross-reactivity with 3-epi-25(OH)D3. Agreement of 25(OH)D assays to ID-LC-MS/MS in sorting patients into distinct 25(OH)D categories varied between 53% and 88%., Conclusions: Significant bias exists between ID-LC-MS/MS and many, but not all, other 25(OH)D assays. The variable response among different assays for 25(OH)D metabolites impedes the use of uniform cut-off values for defining vitamin D status. Our results indicate the need towards further standardizing assays for 25(OH)D measurement., (Copyright © 2012 Elsevier Inc. All rights reserved.)

Background: Measurement of serum 25-hydroxyvitamin D [25(OH)D] is used to assess vitamin D status. We evaluated the analytical performance of a new automated assay, Elecsys Vitamin D Total (Roche Diagnostics, Mannheim, Germany), based on competitive protein binding., Methods: The Elecsys assay was tested for imprecision, linearity and functional sensitivity at three test-sites and compared to a liquid chromatography-tandem mass spectrometry (LC-MS/MS) method, a high-performance liquid chromatography (HPLC) method and the Liaison 25(OH) Vitamin D Total immunoassay (Diasorin)., Results: Imprecision testing with human serum specimens showed within-run CVs of ≤6% and between-run CVs of ≤8%. The assay was linear from 33 up to at least 111 nmol/L and showed equivalent 25(OH)D levels for matched serum and heparinized plasma samples. The assay correlated reasonable to well with LC-MS/MS (r=0.93; y=1.07x-5.04 nmol/L), HPLC (r=0.91, y=0.90x+3.03 nmol/L) and the Liaison assay (r=0.86, y=1.19x+2.80 nmol/L). Some of the samples showed large between-method differences., Conclusions: The new Elecsys assay fulfilled present analytical performance requirements and showed close agreement to other well-established methods for 25(OH)D analysis, making it fit for routine assessment of vitamin D status.

Background: Neutrophil-gelatinase associated lipocalin (NGAL), a tubular injury marker, is associated with iron metabolism in hemodialysis patients. We investigated whether serum NGAL levels reflect iron metabolism in combined chronic heart failure and chronic kidney disease (CHF/CKD) and whether treatment with low-dose erythropoietin stimulating agent (ESA) modulates NGAL levels., Methods: In the EPOCARES trial (ClinTrialsNCT00356733) serum NGAL, hepcidin-25, transferrin saturation (TSAT), reticulocyte hemoglobin content (Ret-He) and endogenous erythropoietin (EPO) levels were measured., Results: Baseline serum NGAL levels correlated with cystatin C (r=0.767, p<0.001) and baseline EPO levels (r=-0.395, p=0.003). There was no correlation with baseline TSAT, Ret-He, and hepcidin-25 levels. After two weeks, NGAL levels decreased in the ESA-group (p=0.02), while there was no change in the no-ESA group (p=0.62). The magnitude in NGAL decrease in the ESA-group correlated with baseline EPO levels (r=0.431, p=0.01)., Conclusions: In contrast to in HD patients, in combined CKD/ CHF, serum NGAL levels did not correlate with iron metabolism, hence NGAL might reflect tubular damage in these patients. NGAL levels inversely correlated with baseline EPO levels and decreased in response to short-term ESA treatment, which might reflect an effect of ESA on tubular damage. These findings need to be confirmed and alternative explanations should be evaluated., (Copyright © 2012 S. Karger AG, Basel.)

Unlabelled: Patients with inflammatory bowel disease (IBD) are at risk of osteoporosis. Vitamin D (vitD) deficiency is known as a risk factor of osteoporosis. We observed low vitD blood levels in adult IBD patients both at the end of summer and winter. Furthermore, effects of oral vitD supplementation in (generally low) daily dosages were poor., Introduction: Patients with IBD are at risk of osteoporosis. This study evaluates seasonal vitD status, determinants of vitD deficiency and effects of vitD supplementation in adult IBD patients., Methods: Patients were screened for vitD deficiency at the end of summer and winter using serum 25OHD(3) (cut-off point, <50 nmol/L) combined with routine laboratory tests. A standardized questionnaire was used for demographic/lifestyle data i.e. IBD activity, health behaviour and vitD intake through diet and ultraviolet light., Results: Late-summer, 39% of the included 316 patients were vitD deficient. Late-winter, 57% of the follow-up patients (n=281) were deficient. Independent protective determinants of vitD deficiency were oral vitD supplementation (summer/winter: odds ratio [OR], 0.52 [95% confidence interval [CI], 0.29-0.94]/OR, 0.44 [95% CI, 0.26-0.75]), recent sun holiday (summer: OR, 0.42 [95% CI, 0.24-0.74]) and regular solarium visits (summer/winter: OR, 0.28 [95% CI, 0.13-0.63]/OR, 0.17 [0.06-0.50]). IBD activity (p=0.031), red blood cell distribution width (RDW; p=0.04) and erythrocyte sedimentation rate (p=0.03) were associated with low vitD levels using univariate analyses of the extreme 25OHD quartiles. In a subgroup with vitD supplementation, still 30% (late-summer) and 44% (late-winter) were vitD deficient., Conclusion: VitD deficiency is common in IBD patients, but prevalence might be comparable with the general population. Ultraviolet light is essential for adequate vitD levels. Effects of oral vitD supplementation in (generally low) daily dosages are poor. Determinants for low vitD levels were IBD activity and elevated inflammatory markers, suggesting that increased risk of osteoporosis in IBD might be more related to the inflammation than to vitD deficiency.

Background: Carbohydrate-deficient transferrin (CDT) is used as a marker for chronic alcohol abuse. The presence of genetic transferrin variants might affect an individual's iron status and can interfere with CDT analysis. We report on the identification of a patient carrying a novel transferrin variant. We describe the performance of the various CDT methods in its detection and the associated iron status., Methods: DNA of the coding region of transferrin was sequenced and CDT levels were analysed using four different methods: high pressure liquid chromatography (HPLC), capillary zone electrophoresis (CZE), immunochemistry and iso-electric focussing (IEF)., Results: A novel transferrin variant, T139M, was found as a heterozygous genotype in the index patient and all of his four living direct family members (c.416C>p.Thr139Met). CDT analysis of the variant by HPLC and CZE was compromised as a result of the coelution of the different isoforms. CDT levels could be quantified by immunochemistry. Similar results were obtained using IEF analysis. The presence of the C2 transferrin variant did not affect iron status in any of the investigated patients., Conclusions: Transferrin T139M, present as a heterozygous genotype, interferes with CDT analysis by HPLC and CZE but not by immunochemistry. Physiologically, it appears to be functionally normal., (Copyright © 2011 Elsevier B.V. All rights reserved.)

Background: Asymptomatic carriage of Giardia intestinalis is highly prevalent among children in developing countries, and evidence regarding its role as a diarrhea-causing agent in these settings is controversial. Impaired linear growth and cognition have been associated with giardiasis, presumably mediated by malabsorption of nutrients. In a prospective cohort study, we aim to compare diarrhea rates in pre-school children with and without Giardia infection. Because the study was conducted in the context of an intervention trial assessing the effects of multi-nutrients on morbidity, we also assessed how supplementation influenced the relationship between Giardia and diarrhoea rates, and to what extent Giardia modifies the intervention effect on nutritional status., Methods and Findings: Data were collected in the context of a randomized placebo-controlled efficacy trial with 2×2 factorial design assessing the effects of zinc and/or multi-micronutrients on morbidity (n=612; height-for-age z-score <-1.5 SD). Outcomes measures were episodes of diarrhea (any reported, or with ≥3 stools in the last 24 h) and fever without localizing signs, as detected with health-facility based surveillance. Giardia was detected in stool by enzyme-linked immunosorbent assay. Among children who did not receive multi-nutrients, asymptomatic Giardia infection at baseline was associated with a substantial reduction in the rate of diarrhea (HR 0.32; 0.15-0.66) and fever without localizing signs (HR 0.56; 0.36-0.87), whereas no such effect was observed among children who received multi-nutrients (p-values for interaction 0.03 for both outcomes). This interaction was independent of age, HAZ-scores and distance to the research dispensary. There was no evidence that Giardia modified the intervention effect on nutritional status., Conclusion: Although causality of the Giardia-associated reduction in morbidity cannot be established, multi-nutrient supplementation results in a loss of this protection and thus seems to influence the proliferation or virulence of Giardia or associated intestinal pathogens.

Background: Carbohydrate-deficient transferrin (CDT) measurement on the multicapillary system Capillarys™ is characterized by high throughput and an on-line sample pre-treatment. This study evaluates the linearity and the precision of this technique, the correlation with the candidate reference method and the effect of genetic transferrin variants. Upper reference limit and cut-off values were calculated., Methods: The precision study was carried out following CLSI EP5-A protocol. The between laboratory variation was calculated from an eight-site study. The upper reference limit (URL) was conventionally calculated from a reference population of 225 samples and verified by a Bhattacharya analysis in a large (n=19,129) population. A population of 314 heavy consumers was used for calculation of the cut-off limit. Additionally the measurement uncertainty was calculated according to EDMA (European Diagnostic Manufacturers Association) and IRMM., Results: The imprecision found was less than 5%, linearity was excellent for CDT values ranging from 2% to 20%. The between site variation around the cut-off value (CDT ranging from 1.68% to 1.79%) was clinically not significant. The upper reference limit (95th percentile) was calculated at 1.3% by the conventional IFCC method and confirmed by Bhattacharya calculations. The optimum cut-off for this CZE method was 1.6%, taken into account the measurement uncertainty. The regression equation with the candidate reference method was Disialotransferrin(Capillarys2)=Disialotransferrin(HPLC)∗0.968-0.248. Genetic variants and abnormal profiles were well recognized., Conclusions: These results demonstrate that the Capillarys CDT method is robust and reliable in routine use with a high degree of homogeneity from one system to another and is highly correlated with the candidate HPLC reference method., (Copyright © 2010 Elsevier B.V. All rights reserved.)

Carbohydrate-deficient transferrin (CDT) is a descriptive term used for a temporary change in the transferrin glycosylation profile caused by alcohol, and used as a biomarker of chronic high alcohol consumption. The use of an array of methods for measurement of CDT in various absolute or relative amounts, and sometimes covering different transferrin glycoforms, has complicated the comparability of results and caused confusion among medical staff. This situation prompted initiation of an IFCC Working Group on CDT standardization. This second publication of the WG-CDT covers the establishment of a network of reference laboratories running a high-performance liquid chromatography (HPLC) candidate reference measurement procedure, and evaluation of candidate secondary reference materials. The network laboratories demonstrated good and reproducible performance and thus can be used to assign target values for calibrators and controls. A candidate secondary reference material based on native human serum lyophilized with a cryo-/lyoprotectant to prevent protein denaturation was found to be commutable and stable during storage. A proposed strategy for calibration of different CDT methods is also presented. In an external quality assurance study involving 66 laboratories and covering the current routine CDT assays (HPLC, capillary electrophoresis and immunoassay), recalculation of observed results based on the nominal values for the candidate calibrator reduced the overall coefficient of variation from 18.9% to 5.5%. The logistics for distribution of reference materials and review of results were found to be functional, indicating that a full reference system for CDT may soon be available.

Setting: Vitamin D deficiency is associated with susceptibility to active tuberculosis (TB) in many settings. In vitro studies and studies on human volunteers showed that two of the first-line anti-tuberculosis drugs, isoniazid and rifampicin, reduce 25-hydroxy vitamin D (25[OH]D) concentrations., Objective: To study changes in vitamin D status during treatment of Tanzanian hospitalised patients with pulmonary TB (PTB)., Design: We compared serum 25[OH]D concentrations in 81 Tanzanian PTB patients before and after 2 months of treatment., Results: Median serum 25[OH]D concentrations increased from 91 nmol/l at baseline to 101 nmol/l after 2 months of TB treatment (median increase 6.0 nmol/l, IQR -0.7-25.0, P = 0.001). Median serum parathyroid hormone concentrations increased from 1.6 to 2.0 pmol/l (median increase 0.46, IQR -0.2-1.1, P < 0.001)., Conclusion: 25[OH]D serum concentrations increased during the first 2 months of TB treatment in 81 PTB patients in northern Tanzania. Improved dietary intake and increased sunlight exposure may have contributed to the increased 25[OH]D concentrations.

Background: The nocturnal endogenous melatonin rise, which is associated with the onset of sleep propensity, is absent in haemodialysis patients. Information on melatonin rhythms in chronic kidney disease (CKD) is limited. Clear relationships exist between melatonin, core body temperature and cortisol in healthy subjects. In CKD, no data are available on these relationships. The objective of the study was to characterize the rhythms of melatonin, cortisol and temperature in relation to renal function in patients with CKD., Methods: From 28 patients (mean age 71 years) with various degrees of renal function, over a 24-h period, blood samples were collected every 2 h. An intestinal telemetric sensor was used to measure core temperature. The presence of diurnal rhythms was examined for melatonin, temperature and cortisol. Correlation analysis was performed between Cockcroft-Gault GFR (GFR), melatonin, cortisol and temperature parameters., Results: The mean GFR was 57 +/- 30 ml/min. The subjects exhibited melatonin (n = 24) and cortisol (n = 22) rhythms. GFR was significantly correlated to melatonin amplitude (r = 0.59, P = 0.003) and total melatonin production (r = 0.51, P = 0.01), but not to temperature or cortisol rhythms. Interestingly, no associations were found between the rhythms of temperature, melatonin and cortisol., Conclusions: As melatonin amplitude and melatonin rhythm decreased with advancing renal dysfunction, follow-up research into circadian rhythms in patients with CKD is warranted.

Vitamin-D deficiency is no longer to be seen only as a cause of osteomalacia, rickets and osteoporosis. There is a causal relationship with muscle function and also with the functioning of our immune system. Furthermore, vitamin-D deficiency is associated with a higher risk of autoimmune diseases and several forms of malignancy, such as prostate, colon and breast cancer. Optimal serum concentration is under discussion which has already led to modification of the recommendations on vitamin-D supplementation. At present, European consensus on 25-hydroxyvitamin-D serum concentrations seems to be a minimum of 50 nmol/l and a target of 75 nmol/l. The majority of the elderly and of non-Western immigrants are deficient or severely deficient in vitamin D and correction of such a deficiency with bolus therapy should be considered. Awareness of a vitamin-D deficiency is needed in unexplained complaints of muscle weakness or muscle pain, and in the risk groups, such as the elderly, non-Western immigrants, the chronically ill, indoor living and institutionalized, those who habitually use sun protection cream, and severely obese patients.

Background: An incomplete separation of disialotransferrin (CDT) and trisialotransferrin (a non-CDT isoform) may cause false-positive CDT results in alcohol abuse testing. We describe a currently unknown disialotransferrin-trisialotransferrin-bridging phenomenon (di-tri-bridge) appearing with high prevalence in serum from liver cirrhosis patients., Methods: Twenty one consecutive serum samples with a di-tri-bridge encountered in routine CDT HPLC (Clin-Rep(R)-CDT-on-line, Recipe) were investigated by a candidate reference CDT HPLC method, by capillary electrophoresis (Capillarys-CDT, Sebia) and by transferrin genotyping. Patients clinical background was assessed by telephone interview., Results: Out of 21 consecutive serum samples showing a di-tri-bridge (and increased trisialotransferrin fractions) in HPLC as well as in CE analysis, 19 were from patients with a liver cirrhosis history. Genotyping (where applicable by the availability of DNA: n=12) yielded most frequently homozygous transferrin C1 (6x), proving that the di-tri-bridge cannot be explained by genetic transferrin variants in these samples. Other genotypes found were C2 (1x), C1C2 (4x), C1C3 (1x)., Conclusion: The frequently seen di-tri-bridging phenomenon in transferrin HPLC analysis for patients with liver cirrhosis is not explained by genetic transferrin variants or by an increased trisialotransferrin fraction. Although further studies are needed to assess the relationship between this phenomenon and liver cirrhosis, our observation could be helpful in development of a biomarker for liver cirrhosis.

Objective: Because vitamin D synthesis is lower in a heavily pigmented skin than in a lighter skin, the relative contribution of determinants to the vitamin D concentration might differ between ethnic groups. The aim of this study was to assess the prevalence of vitamin D deficiency and the relative contribution of vitamin D consumption and exposure to sunlight to the vitamin D concentration in a multiethnic population., Design: Cross-sectional study., Patients: A total of 613 adults aged 18-65 years from a random sample from general practices in the Netherlands (52 degrees N, 2003-05), stratified according to gender and ethnic group., Measurements: Serum 25-hydroxyvitamin D [25(OH)D], PTH, ethnic group, sunlight exposure, consumption of foods and supplements rich in vitamin D., Results: The prevalence (95% confidence interval) of vitamin D deficiency [serum 25(OH)D < 25 nmol/l] was higher in Turkish (41.3%; 32.5-50.1), Moroccan (36.5%; 26.9-46.1), Surinam South Asian (51.4%; 41.9-60.9), Surinam Creole (45.3%; 34.0-56.6), sub-Saharan African (19.3%; 9.1-29.5) and other adults (29.1%; 17.1-41.1) compared to the indigenous Dutch (5.9%; 1.3-10.5). Modifiable, significant determinants (standardized regression coefficients) for serum 25(OH)D concentration were: consumption of fatty fish (0.160), use of vitamin D supplements (0.142), area of uncovered skin (highest category 0.136; middle category 0.028), use of tanning bed (0.103), consumption of margarine (0.093) and preference for sun (0.089). We found no significant modification of ethnic group on the effect of sunlight determinants., Conclusion: Of the modifiable determinants, fatty fish and supplements are the greatest contributors to the serum 25(OH)D concentration in a multiethnic population.

Background: Urine microscopic analysis is hampered by its lack in standardisation and semi-quantitative reports, resulting in limited reliability. Automation of urinalysis could overcome these problems., Methods: We compared the performance of the iQ200 with traditional microscopy and strip analysis in routine urinalysis. A total of 1482 routine samples, positive in dipstick testing, were evaluated for erythrocytes, leukocytes, casts, dysmorphic erythrocytes and bacteria using the iQ200 and traditional microscopy. The results of 320 of these samples were linked to underlying urological pathology as well as results from bacterial culturing., Results: Analytically, the iQ200 surpasses traditional microscopy. The identification of casts and dysmorphic erythrocytes in routine samples improves when using the iQ200, although the sub-classification of casts required well-trained technicians. The auto-classification of particles was least reliable for yeast and bacterial cocci. The quantitative reports, and therefore the use of precise cut-off points allowed earlier and improved detection of urinary tract pathology., Conclusions: The performance of the iQ200 is equal to traditional microscopy, but it strongly improves the reliability of urinalysis by standardisation, quantitative reports and improved workflow. From a clinical point of view, renewed attention and improvement of routine urinalysis aids in the efficient detection of renal and urinary tract pathology.

Background: alpha(1)-Antitrypsin (alpha(1)AT) deficiency predisposes individuals to chronic obstructive pulmonary disease (COPD) and/or liver disease. Phenotyping of the protein by isoelectric focusing is often used to characterize alpha(1)AT deficiency, but this method may lead to misdiagnosis (e.g., by missing null alleles). We evaluated a workup that included direct sequencing of the relevant parts of the gene encoding alpha(1)AT, SERPINA1 [serpin peptidase inhibitor, clade A (alpha-1 antiproteinase, antitrypsin), member 1], for patients with alpha(1)AT concentrations < or =1.0 g/L., Methods: During a 5-year period, we identified 66 patients with alpha(1)AT concentrations < or =1.0 g/L and amplified and sequenced exons 2, 3, and 5 of the alpha(1)AT gene in these patients. To ensure that no relevant genotypes were missed, we sequenced the same exons in 48 individuals with alpha(1)AT concentrations between 1.0 and 1.5 g/L., Results: Sequence analysis revealed 18 patients with combinations of disease-associated alpha(1)AT alleles: 8 homozygous for the deficient Z allele and 10 compound heterozygotes for various deficient or null alleles. We identified and named 2 new null alleles, Q0(soest) (Thr(102)-->delA, which produces a TGA stop signal at codon 112) and Q0(amersfoort) (Tyr(160)-->stop). No relevant disease-associated allele combinations were missed at a 1.0-g/L threshold., Conclusions: Up to 22% of the alleles in disease-associated alpha(1)AT allele combinations may be missed by conventional methods. Genotyping by direct sequencing of samples from patients with alpha(1)AT concentrations < or =1.0 g/L detected these alleles and identified 2 new null alleles.

Background: Carbohydrate-deficient transferrin (CDT) is a promising biomarker of alcohol abuse. We describe the development and multicenter evaluation of N Latex CDT (Dade Behring), an automated, particle-enhanced, homogeneous immunonephelometric assay for directly determining CDT., Methods: N Latex CDT uses a monoclonal antibody that recognizes the structure of transferrin glycoforms lacking 1 or 2 complete N-glycans [i.e., disialo-, monosialo-, and asialotransferrins (CDT glycoforms)] in combination with a simultaneous assay for total transferrin. The Dade Behring BN II and BN ProSpec systems automatically calculate the CDT value as a percentage of total transferrin (%CDT). No preanalytical sample treatment is used., Results: Total imprecision values for serum pools containing 1.8%-8.7% CDT were 3.4%-10.4% (mean, 6.8%). The mean (SD) %CDT for 561 serum samples from healthy control individuals was 1.76% (0.27%; range, 1.01%-2.85%). No marked sex or age differences were noted. The 97.5th percentile was at 2.35%. Transferrin genetic variants did not interfere with measurements. High transferrin concentrations did not falsely increase %CDT values, but increased %CDT values were noted for some samples with transferrin concentrations <1.1 g/L. N Latex CDT results correlated with those of a commercial CDT immunoassay involving column separation (r(2) = 0.862) and an HPLC candidate reference method (r(2) = 0.978)., Conclusion: N Latex CDT is the first direct immunoassay for quantifying %CDT in serum. The specificity of N Latex CDT for identifying alcohol abuse may be higher than for immunoassays that use column separation, because transferrin genetic variants do not interfere with measurements.

An alcohol-associated change in the serum transferrin glycoform pattern, carbohydrate-deficient transferrin (CDT), is used as a biomarker of chronic moderate to heavy alcohol consumption. A current limitation in CDT analysis is the lack of standardization, which hampers clinical and analytical comparison between studies. This situation prompted initiation of a Working Group (WG) on CDT Standardization under the auspices of the International Federation of Clinical Chemistry and Laboratory Medicine (IFCC). The standardization work aims to define and validate the analyte, select a reference method, work out procedures for the production of reference materials, and make suggestions for the clinical usage of CDT. The first recommendation of the WG is that disialotransferrin should be the primary target molecule for CDT measurement and the single analyte on which CDT standardization is based. It is further recommended that HPLC should be the analytical principle considered as the basis of an interim reference method until a suitable mass spectrometric reference method is established. In clinical use, CDT should be expressed in a relative amount (% CDT), to compensate for variations in the total transferrin concentration.

Objective: To determine the prevalence of vitamin-D deficiency in pregnant women and their newborns., Design: Descriptive., Method: During the period of one year (April 2004-April 2005) 545 pregnant women of Dutch/European origin and 131 pregnant women of non-Western origin (mainly Turkish and Moroccan) were studied during their 10th and/or 30th week of pregnancy for calcidiol (vitamin-D) and calcium levels. The study took place in the Amersfoort region in the center of the Netherlands. In addition, cord blood samples were taken for vitamin-D and calcium levels from the 442 and 81 Dutch/European and non-Western newborns respectively., Results: A severe deficiency was found (calcidiol < 20 nmol/l) in 55% of non-European women compared to 5% of Dutch/West-European women. From the cord blood samples, a severe vitamin-D deficiency (calcidiol < 13 nmol/l) was found in 54% of the newborns of non-European origin compared to 6% of the Dutch/West-European newborns. Vitamin-D concentrations in pregnant women at term were strongly correlated to the concentrations in the newborns' cord blood (R = 0.84). The calcium levels of pregnant women and newborns did not differ significantly between both population groups., Conclusion: More than half of the non-European pregnant women and their newborns had a severe vitamin-D deficiency. Screening for vitamin D deficiency and adequate suppletion for this risk group appears to be necessary. The causes and consequences of vitamin-D deficiency in pregnancy are discussed.

In a group of 34 psychogeriatric patients (mean age 79 years) the prevalence of hypovitaminosis D was found to be 82%, taking 30 nmol/l as cut-off for calcidiol. We found 47% of the whole group to be severely deficient having values lower than 20 nmol/l. Results of related test are presented and discussed. Patient were treated with oral calcium and vitamin D3 medication. Origin, presentation and risks of hypovitaminosis D, including muscle weakness and the aggravating role of low calcium intake, are discussed with special attention to psychogeriatric patients. Suppletion of vitamin D and calcium is suggested for this patient group.

A 16-year-old girl had symptoms of vomiting, malaise and weight loss for two months. Blood tests revealed an elevated activity of liver enzymes and hyperthyroidism. Although the patient at first denied the possibility of pregnancy, a pregnancy was subsequently confirmed. Hyperemesis gravidarum was diagnosed based on the combination of the clinical symptoms, pregnancy and increased serum human chorionic gonadotrophin and oestradiol. Hyperemesis gravidarum also explained the demonstrated biochemical hyperthyroidism and elevated liver enzyme levels. Rapid alleviation of all the clinical symptoms was seen after termination of this unwanted pregnancy. Although vomiting, malaise and weight loss in children can have many different causes, in girls at a sexually mature age a pregnancy with possible hyperemesis gravidarum should certainly also be considered and a gynaecological examination performed.

Objective: To describe the determinants of insulin sensitivity (IS) in chronic heart failure (CHF), we created a model in which the influence of lifestyle factors and etiology of heart failure on IS were incorporated concomitantly with age, left ventricular ejection fraction (LVEF) and parameters of body composition., Design: Observational cohort study., Setting: Outpatient clinic for chronic heart failure., Patients: Fifty-seven male CHF patients [NYHA class II-III, age 61+/-9 years, body mass index (BMI) 26.9+/-3.3 kg/m2 (mean+/-S.D.)]., Interventions: Euglycemic hyperinsulinemic clamp, cycle ergometry, anthropometric measurements, LVEF and a physical activity questionnaire., Main Outcome Measures: A model explaining the variance of IS in CHF., Results: IS was 18.2+/-8.6 microg.kg(-1).min(-1).mU(-1).l(-1), fasting insulin level was 15.9+/-11.0 mU/l and fasting glucose level was 5.5+/-0.6 mmol/l. Peak VO2 was 19.1+/-4.9 ml.kg(-1).min(-1) and LVEF 26.2+/-7.1%. IS was inversely associated with fasting insulin concentration (r=-0.50, P<0.001) and BMI (r=-0.54, P<0.001). After controlling for BMI, IS also revealed a correlation with age (r=-0.36, P<0.01). The model explained 60% of variance in IS: BMI contributed 20%, smoking 17%, age 17% and physical activity in daily life (DPA) 16% (all P<0.05) to the variance of IS, whereas LVEF (9%) and etiology of heart failure (8%) contributed moderately., Conclusions: In CHF patients, IS is for a major part predicted by BMI, smoking, age, daily physical activity, LVEF and etiology of heart failure.

A pilot study was performed in March 2001 in order to estimate the prevalence of hypovitaminosis D in veiled women in the Netherlands. In a group of 51 Turkish women aged 14-63 years, 42 (82%) were severely deficient (25-hydroxyvitamin D (25-(OH)D) < 20 nmol/l), and 4 (8%) were moderately deficient (25(OH)D: 20-30 nmol/l). About half of the deficient women complained of muscle pain, muscle weakness or fatigue. These results confirm the presence of a serious public health problem with regard to vitamin D amongst veiled women.

We studied the prevalence of zinc deficiency in patients who were hospitalised in a geriatric ward and its association with risk factors for this deficiency and the possible symptoms. The serum zinc level was measured from 45 consecutive admissions to a geriatric ward and patient characteristics were collected. A peer group of healthy subjects originating from a population survey was used as a control group. The serum zinc measured in the admitted patients was significantly lower than the reference value for adults (65.8% had a lowered zinc level) and the serum zinc for healthy elderly. There was no association found with possible causes of zinc deficiency. In an univariate analysis lethargy was the only significant association to zinc deficiency. There was a reverse relationship between the sum of the number of present symptoms and the zinc proportion A lower zinc level is associated with symptoms of zinc deficiency. As more symptoms appear the probability of zinc deficiency is greater. The importance for the clinical practice based on present knowledge is discussed.

Purpose: Studies on the effect of exercise on gastrointestinal (GI) mucosal integrity have been limited to occult-blood tests, which were often nonspecific for human blood. The aim of our study was to investigate more aspects of this integrity., Methods: We examined the effect of prolonged exercise and carbohydrate (CHO) supplementation on mucosal integrity in 22 male triathletes by measuring fecal lysozyme, alpha1-antitrypsin, and occult-blood loss, which was examined by two tests specific for human blood (Colon-Albumin and Monohaem test). Exercise consisted of two 150-min tests (alternately running, cycling, and running at 70-75% VO2max), either with a 7.0% CHO drink or water (W). Furthermore, GI symptoms during exercise were registered by questionnaire., Results: Three subjects showed human albumin only in the first stool after exercise: twice with W and once with CHO. However, human hemoglobin (Hb) could not be detected in these samples. Four other subjects showed an elevated lysozyme concentration after exercise with CHO but not with W. Elevated alpha1-antitrypsin values were found in three of seven specimens in which either positive albumin tests and/or an elevated lysozyme concentration were demonstrated. Twenty-one subjects (95%) reported one or more GI symptoms during exercise. Incidence rates of different GI symptoms varied from 5 to 68%. Most symptoms were more frequent and lasted longer during running than during cycling but did not differ significantly between supplements and were not related to any mucosal integrity parameter., Conclusions: GI blood loss during exercise is of no clinical importance, at least in our study design with a group of well-trained male subjects who consumed a relatively high amount of fluid (up to 2.3 L). Nevertheless, an increased alpha1-antitrypsin and lysozyme concentration may indicate a transient local mucosal damage with an inflammatory response.

Oxidation of low density lipoprotein cholesterol (LDL-c) is supposed to play a role in the generation of atherosclerotic lesions. Grape derived beverages supply a large number of nutritional antioxidants because of their high content of polyphenols. This might be one of the mechanisms behind the supposed beneficial effect of red wine. Wine also contains alcohol and its role in oxidation processes especially in vivo is unclear. In this study the effect of daily red wine consumption for 2 weeks on oxidizability status of LDL was investigated. The role of alcohol in LDL oxidation was further explored in in vitro experiments. After abstinence from alcoholic beverages, grape juices and tea for a week, seven healthy male volunteers consumed 375 ml of red wine (30 g alcohol) per day during 2 weeks. At the start and end of the drinking period blood samples were taken and the susceptibility of LDL-c to copper-induced oxidation was analyzed with the addition of distilled water (control) and dilutions of a 12% alcohol solution, white wine and red wine. Although red wine at concentrations achievable in vivo caused a significant prolongation of the lag-time of metal ion dependent LDL oxidation in vitro (85.9+/-23.0-114.1+/-30.8 min, P<0. 001), a significant shortening of lag-time was found in vivo after the 2 weeks of wine consumption (56.3+/-13.0 min, P<0.001). A shorter lag-time compared to the control was found for both alcohol and white wine in vitro. The changed oxidizability status of LDL after 2 weeks of wine consumption made it more susceptible for the in vitro antioxidant effect of red wine. At low dilutions red grape juice extended lag-time as well, which was not influenced by the addition of alcohol. Red wine has a strong inhibitory effect on copper-induced oxidation of LDL in vitro, while red grape juice has a minor effect, an effect which should be attributed to the non alcohol components in the beverages. In vivo, however, this effect can be overshadowed by the prooxidant influence of alcohol. The balance between alcohol and polyphenols of a wine may be critical for its in vivo effect on LDL oxidation.

Background: Lower plasma magnesium concentrations are associated with clinical problems such as arrhythmias and hypertension. Plasma magnesium concentration is tightly controlled by the kidney. Modifying renal magnesium threshold may provide a means to increase the plasma magnesium concentration. Since evidence has been presented that potassium deficiency by itself may increase renal magnesium loss, the hypothesis that elevating plasma potassium would result in an increase in plasma magnesium concentration was tested in healthy volunteers., Methods: Plasma potassium was raised in nine healthy volunteers by oral administration of 20 mg amiloride daily during 3 weeks. Magnesium metabolism was assessed before and after this period by plasma levels, urinary magnesium excretion and fractional magnesium excretion, and magnesium loading test (MLT). This MLT allows calculation of renal retention of a magnesium load., Results: Basal plasma magnesium levels (0.84 +/- 0.07 vs 0.84 +/- 0.05 mmol/l) as well as urinary magnesium excretion (4.37 +/- 1.73 vs 3.67 +/- 1.37 mmol/day) and erythrocyte magnesium levels (1.72 +/- 0.16 vs 1.76 +/- 0.14 mmol Mg/l red blood cells) were similar before and on amiloride. Plasma potassium rose significantly on amiloride (3.64 +/- 0.24 vs 4.07 +/- 0.54 mmol/l, P < 0.05). No change was observed in magnesium retention with the MLT: 22.7 +/- 26.7 vs 29.2 +/- 20.6% (P = 0.5)., Conclusions: Despite an increased plasma potassium concentration, no change was observed in plasma magnesium levels, urinary magnesium excretion or renal magnesium retention of an intravenously administered magnesium load. This indicates that increasing plasma potassium within the normal range does not modify the renal magnesium threshold.

Neuron-specific enolase and carcino-embryonic antigen were quantified simultaneously in sera of 135 patients attending the Department of Respiratory Diseases for diagnostic bronchoscopy. Fifteen small cell lung carcinomas, 24 non-small cell lung carcinomas and 96 benign pulmonary diseases were investigated. Lung biopsies or bronchial washings were obtained from about 75% of the patients, including all patients with neoplastic diseases. Serum neuron-specific enolase was measured by a recently introduced enzyme-immuno assay (WaKo NS-Enolase EIA-II testkit). The results obtained with this kit were similar to those based on RIA assays. Receiver Operating Characteristic curves (ROC curves) were constructed for comparison of the discriminating ability of neuron-specific enolase and carcino-embryonic antigen in small cell lung carcinomas and non-small cell lung carcinomas. For small cell lung carcinomas the sensitivity and the specificity of neuron-specific enolase (cutoff value: 10 micrograms/l) were 87% and 88%, respectively, and for carcino-embryonic antigen values 60% and 77% were obtained. There was no correlation between neuron-specific enolase and carcino-embryonic antigen in small cell lung carcinoma patients. The diagnostic value of neuron-specific enolase and carcino-embryonic antigen in non-small cell lung carcinomas is illustrated by sensitivities of 13% and 58%, respectively. An extensive literature survey is included to allow comparison with other studies. The use of ROC curves is recommended for the determination of optimal cutoff values for the assays employed.

1. ADP binding to beef-heart mitochondrial ATPase (F1), in the absence of Mg2+, has been determined by separating the free ligand by ultrafiltration and determining it in the filtrate by a specially modified isotachophoretic procedure. 2. Since during the binding experiments the 'tightly' bound ADP (but not the ATP) dissociates, it is necessary to take this into account in calculating the binding parameters. 3. The binding data show that only one tight binding site (Kd about 0.5 microM) for ADP is present. 4. It is not possible to calculate from the binding data alone the number of or the dissociation constants for the weak binding sites. It can be concluded, however, that the latter is not less than about 50 microM.