Gönül Erden

Biological variation and reference change values of CA 19‐9, CEA, AFP in serum of healthy individuals

Objective. The use of tumour markers in diagnosis and monitoring is very common. Tumour marker results vary – preanalytical sources of variation, total random analytical error (CVa), and within‐subject (intraindividual) normal biological variation. There are not so many studies evaluating the biological variations and reference change values (RCV) of these parameters. The aim of our study was to assess: (i) the average inherent intra‐ and inter‐individual biological variation (CVi and CVg) for CA 19‐9, CEA, AFP in a group of healthy individuals; (ii) the significance of changes in serial results of each marker; and (iii) the index of individuality. Material and methods. The study group comprised 49 healthy volunteers ranging in age between 18 and 60 years (25 M and 24 F). Four blood samples were obtained from each subject; one at each 14‐day interval. Each sample from one individual was assayed in duplicate. CA 19‐9, CEA, AFP levels were measured by an immunoluminometric assay on a random‐access analyser (Architect i2000; Abbott Diagnostics Division). The intra‐ (CVi) and inter‐individual (CVg) biological variations were estimated from the data generated. Reference change value (RCV) was calculated. Results. The intra‐individual/inter‐individual biological variations (CVs) for CA 19‐9, CEA, AFP were 27.2/64.24 %, 30.87/37.14 % and 26.67/43.65 %, respectively. The critical differences (RCVs) of CA 19‐9, CEA, AFP were 64.71 %, 72.57 % and 62.62 %, respectively (Z = 1.65 for unidirectional changes; p<0.05). Conclusions. Intra‐individual biological variation contributes to the variation in serial results and should therefore be included in the criteria for serum tumour marker assessment.

Plasma homocysteine concentrations and serum lipid profile as atherosclerotic risk factors in subclinical hypothyroidism.

BACKGROUND AND OBJECTIVES Because subclinical thyroid dysfunction may be a risk factor for cardiovascular disease, we evaluated the atherosclerosis tendency in subclinical hypothyroid (SCH) patients. PATIENTS AND METHODS Fifty-three subclinical hypothyroid patients (serum thyrotropin [TSH] concentrations >4.12 mU/L) were compared with a control group of 50 euthyroid subjects whose age, sex and body mass indices were similar to the patient group. We tested whether serum TSH concentrations were correlated with plasma total homocysteine concentration (tHcy), low-density lipoprotein cholesterol (LDL-C), very low-density lipoprotein cholesterol (VLDL-C), high-density lipoprotein cholesterol (HDL-C), total cholesterol (TC) and triglycerides (TG). RESULTS There was a significant statistical difference between the patient and control groups for normal free T4 (1.02±0.17 vs. 0.86±0.13, P<.001), TSH (1.64±1.02 vs. 6.62±2.61, P<.001), TC (185±39 vs. 206±42, P=.01), TG (103±54 vs. 132±85, P=.04), LDL-C (114±33 vs. 127±36, P=.04), and TC/HDL-C (3.81±106 vs. 4.19±1.02, P=.04), respectively. No statistically significant difference was found between the two groups for HDL-C, VLDL-C, LDL-C/HDL-C, and tHcy. Serum TSH was significantly correlated with plasma tHcy (r=0.55; P=.001), TC (r=0.52; P=.001), LDL-C (r=0.49; P=.001), TC/HDL-C (r=0.38; P=.002) and LDL-C/HDL-C (r=0.36; P=.004) across all participants. CONCLUSION Our study suggests that the atherogenicity of SCH is not mediated by hyperhomocysteinemia. Associated hyperlipidemia may explain the observed increased risk of coronary artery disease in patients with SCH.

Thymosin beta 4 is associated with collateral development in coronary artery disease

Abstract Objectives: Thymosin beta 4 (Tβ4) plays an essential role in cardiac vessel development and is currently being developed as a therapeutic agent for the treatment of coronary artery disease (CAD) in some experimental studies. Thus, we aimed to investigate the association of serum Tβ4 levels and collateral formation in patients presenting with severely stenotic CAD. Methods: Thirteen patients with poor collateral development and 16 age- and sex-matched patients with good collateral development who had ≥ 95% stenosis in at least one major coronary artery on coronary angiogram (CAG) were enrolled in the study. The Gensini score was calculated for each patient by using CAG results. Collateral development was classified according to the Cohen-Rentrop method. Serum Tβ4 levels were measured with enzyme-linked immune sorbent assay. Results: There were no statistically significant differences between the two groups in regard to clinical and laboratory characteristics of the patients except for Tβ4 levels. The Tβ4 levels in the well-collateralized study group were found to be significantly higher than those of the poorly collateralized study group and serum Tβ4 levels were positively correlated with the collateral development. Conclusions: Our findings suggest that serum Tβ4 levels are significantly associated with the collateral development in severe CAD.

Effect of Serum Gamma-Glutamyl Transferase Levels on Myocardial Perfusion and Long-Term Prognosis After Primary Angioplasty in Patients With Acute ST-Elevation Myocardial Infarction

Background Gamma-glutamyl transferase (GGT) level was found to be elevated in plasma of patients with cardiovascular risk factors. The aim of our study was to assess the relationship between serum GGT levels and the occurrence of no-reflow as well as to evaluate the prognostic value of GGT in ST-segment elevation myocardial infarction (STEMI) population. Methods and Results One hundred sixty-eight consecutive patients with STEMI who underwent percutaneous coronary intervention (PCI) were enrolled in the study. Patients with STEMI were grouped into tertiles according to their admission serum GGT levels. No-reflow after PCI was assessed both angiographically (thrombolysis in myocardial infarction [TIMI] flow and myocardial blush grade) and electrocardiographically (ST resolution). Gamma-glutamyl transferase levels were higher in patients with STEMI compared to the elective PCI group subjects. Patients with angiographically (TIMI flow ⩽2 or TIMI flow 3 with final myocardial bush grade ⩽2 after PCI) and electrocardiographically (ST resolution <30%) detected no-reflow were increased in number across the GGT tertiles. In addition, 1-year mortality rates showed a significant increase across the tertile groups (4% vs 11% vs 23%, P < 0.01). Multivariable logistic regression analysis revealed that GGT levels on admission were a significant predictor of long-term mortality of myocardial blush grade–detected no-reflow phenomenon. High GGT level on admission was a significant predictor for long-term mortality and major adverse cardiac events. Conclusions In patients with STEMI undergoing primary PCI, high GGT levels at admission were found to be associated with no-reflow phenomenon and increased long-term mortality.

Human Endothelial Cell-Specific Molecule-1 (Endocan) and Coronary Artery Disease and Microvascular Angina

Endothelial cell-specific molecule-1 (endocan) is an immunoinflammatory marker linked to endothelial activation and dysfunction. We investigated the relationship between obstructive coronary artery disease (CAD), microvascular angina (MVA), and plasma levels of endocan. We included 53 healthy individuals as controls, 40 MVA patients, and 120 patients with obstructive CAD. The severity of CAD was assessed by the Gensini and SYNergy between percutaneous coronary intervention with TAXUS and Cardiac Surgery (SYNTAX) scores. Endocan levels were 382.7 (313.8-470.2) pg/mL in patients with obstructive CAD; 324.3 (277.1-460.7) pg/mL in MVA group, and 268.0 (226.4-336.5) pg/mL (P < .001) in controls. Endocan levels in obstructive CAD and MVA groups were similar but both were significantly higher than for the control group (P < .001 and P = .002, respectively). In subgroup analysis, similar to the hypertensive subgroup results, endocan was still an independent predictor of presence of obstructive CAD in normotensives (odds ratio = 1.005, 95% confidence interval = 1.001-1.010, P = .024). There was also an independent positive correlation between endocan levels and SYNTAX score both in the hypertensives (β = 0.414, t = 3.21, P = .002) and in the normotensives (β = .301, t = 2.23, P = .031). In conclusion, endocan could be a common predictor of the endothelium-dependent inflammatory processes, rather than related with specific risk factors.

Pesticide poisoning cases in Ankara and nearby cities in Turkey: An 11-year retrospective analysis

Since they are available in open markets and pharmacies, pesticides have been widely used all over the country. (Un)intentional poisoning with these compounds is one of the most common causes of chemical poisoning, especially in rural agricultural areas. Pesticide poisonings reported by various countries showed that it is a worldwide health problem with 250,000-370,000 associated deaths each year. In this study, medico-legal deaths between the years 2001 and 2011 in Ankara and nearby cities in Turkey were investigated retrospectively. The autopsies were partly carried out by Ankara Branch of Council of Forensic Medicine. Data were collected from reports of the Morgue Department whose toxicological analyses were performed in the Chemistry Department. The data revealed that 70 cases out of 10,720 autopsied ones had been attributed to fatal pesticide poisoning. The age range was 1-80 years (mean ± SD, 41.33 ± 17.42 years). Most of the cases (60%) were reported from Ankara. Insecticides were the most common (94%) cause of fatal pesticide poisonings, most of them (63%) being organophosphate insecticides. The percentages of pesticide-induced deaths are quite high in our society and should therefore not be underestimated. Accordingly, intensive efforts to reduce occupational and intentional pesticide poisonings are urgently needed in Ankara and nearby cities.

Estimation of biological variation and reference change value of glycated hemoglobin (HbA1c) when two analytical methods are used

OBJECTIVES Available data on biological variation of HbA1c revealed marked heterogeneity. We therefore investigated and estimated the components of biological variation for HbA1c in a group of healthy individuals by applying a recommended and strictly designed study protocol using two different assay methods. DESIGN AND METHODS Each month, samples were derived on the same day, for three months. Four EDTA whole blood samples were collected from each individual (20 women, 9 men; 20-45 years of age) and stored at -80°C until analysis. HbA1c values were measured by both high performance liquid chromatography (HPLC) (Shimadzu, Prominence, Japan) and boronate affinity chromatography methods (Trinity Biotech, Premier Hb9210, Ireland). All samples were assayed in duplicate in a single batch for each assay method. Estimations were calculated according to the formulas described by Fraser and Harris. RESULTS The within subject (CV(I))-between subject (CV(G)) biological variations were 1.17% and 5.58%, respectively for HPLC. The calculated CV(I) and CV(G) were 2.15% and 4.03%, respectively for boronate affinity chromatography. Reference change value (RCV) for HPLC and boronate affinity chromatography was 5.4% and 10.4% respectively and individuality index of HbA(1c) was 0.35 and 0.93 respectively. CONCLUSIONS This study for the first time described the components of biological variation for HbA1c in healthy individuals by two different assay methods. Obtained findings showed that the difference between CV(A) values of the methods might considerably affect RCV. These data regarding biological variation of HbA(1c) could be useful for a better evaluation of HbA(1c) test results in clinical interpretation.

Greater Efficiency Observed 12 Months Post-Implementation of an Automatic Tube Sorting and Registration System in a Core Laboratory/ Veća Efikasnost Uočena 12 Meseci Posle Implementacije Sistema za Automatsko Sortiranje i Registrovanje Uzoraka u Centralnoj Laboratoriji

Summary Bachground: Sample classification and registration have been recognized as important and time-consuming processes in laboratories. There is increasing pressure on laboratories to automate processes due to intense workload and reduce manual procedures and errors. The aim of the present study was to evaluate the positive effects of an automatic tube registration and sorting system on specimen processing. Methods: An automatic tube registration and sorting system (HCTS2000 MK2, m-u-t AG, Wedel, Germany) was evaluated. Turnaround time (TAT), rate of sample rejection and unrealized tests were examined 12 months pre- and post-implementation of the automatic tube sorting and registration system. Results: The mean TAT of routine chemistry immunoassay, complete blood cell count (CBC) and coagulation samples were significantly improved (P<0.001). The number of rejected samples and unrealized tests was insignificantly decreased post-implementation of the system (0.4% to 0.2% and 4.5% to 1.4%, respectively) (P>0.05). Conclusions: By reducing delays and errors in the preanalytical processing and sorting of samples, significant improvements in specimen processing were observed after implementation of the system. These results suggest that an automatic tube registration and sorting system may also be used to improve specimen processing in a higher-volume core laboratory. Kratak sadržaj Uvod: Klasifikacija i registracija uzoraka u laboratorijama prepoznate su kao važni i dugotrajni procesi. Laboratorije su pod sve većim pritiskom da automatizuju postupke zbog velikog obima posla i smanje manuelne procedure i greške. Cilj ove studije bio je da se procene pozitivni efekti jednog sistema za automatsko registrovanje i sortiranje uzoraka na njihovu obradu. Metode: Ocenjivali smo sistem za automatsko registrovanje i sortiranje uzoraka (HCTS2000 MK2, m-u-t AG, Wedel, Nemačka). Ukupno vreme za obradu uzorka (turnaround time), stopa odbacivanja uzorka i nerealizovani testovi obradeni su 12 meseci pre i posle implementacije sistema za automatsko sortiranje i registrovanje uzoraka. Rezultati: Srednje ukupno vreme obrade uzoraka za rutinske hemijske imunoeseje, kompletnu krvnu sliku i koagulaciju bilo je značajno bolje (P<0,001). Broj odbačenih uzoraka i nerealizovanih testova bio je smanjen, iako ne značajno, posle implementacije sistema (sa 0,4% na 0,2%, odnosno sa 4,5% na 1,4%) (P>0,05). Zaključak: Zahvaljujući ređim slučajevima kašnjenja i redim greškama prilikom preanalitičke obrade i sortiranja uzoraka, uočena su značajna poboljšanja u obradi uzoraka posle implementacije ovog sistema. Naši rezultati pokazuju da se sistemi za automatsko registrovanje i sortiranje mogu koristiti radi poboljšane obrade uzoraka i u centralnim laboratorijama sa velikim obimom posla.

Evaluation of the analytical performance of Unicel DXI 800 for the Total 25 (OH) Vitamin D measurements.

OBJECTIVES We assessed the analytical performance of newly developed Access 25(OH) Vitamin D Total assay with Beckman Coulter Unicel DXI 800 and evaluated the agreement between a reference method liquid chromatography/tandem mass spectrometry (LC-MS/MS) and a chemiluminescence method (LIAISON, DiaSorin). DESIGN AND METHODS 160 serum samples were included. Deming Regression analysis and Bland-Altman plots were used. The concordance correlation coefficient (CCC) was used to assess the degree of agreement between assays and the reference method. RESULTS The CV% values of Unicel DXI 800 for within-run, between-run and between-day were lower than 6%. When compared to LC-MS/MS, the Access 25(OH) Vitamin D Total assay demonstrated an R value of 0.9444 (intercept -0.089, slope 0.951), with an average bias of -2.9%, and the LIAISON 25(OH) Vitamin D Total assay an R value of 0.9405 (intercept -0605, slope 0.924), with an average bias of -13.6%. In comparison with the LIAISON 25(OH) Vitamin D Total assay, the Access 25(OH) Vitamin D Total assay demonstrated an R value of 0.9498 (intercept 0.528, slope 1.029), with an average bias of 1.2%. The agreement with the LC-MS/MS method, based on values of the CCC, was moderate for the Unicel DXI 800 and LIAISON method (0.95, 0.94 respectively). CONCLUSIONS The new, automated Access 25(OH) Vitamin D Total assay showed an acceptable correlation with LC-MS/MS and LIAISON. Both methods moderately achieved to classify the patients according to their vitamin D status. However, we need further standardization of vitamin D assays to enhance the accuracy and comparability.

Interleukin-1β induced nuclear factor-κB binds to a disintegrin-like and metalloproteinase with thrombospondin type 1 motif 9 promoter in human chondrosarcoma cells

Nuclear factor-κB (NF-κB) is involved in the regulation of inflammation‑associated genes. NF-κB forms dimers which bind with sequences referred to as NF-κB sites (9-11 bp). A disintegrin-like and metalloproteinase with thrombospondin type 1 motif 9 (ADAMTS9) is a type of proteoglycanase, which proteolytically cleaves versican and aggrecan. ADAMTS9 is a cytokine-inducible gene that contains binding sites for NF-κB within its promoter region. Interleukin-1β (IL-1β) affects cartilage metabolism and is involved in the NF-κB pathway. It is therefore hypothesized that NF-κB binding with ADAMTS9 promoters may activate IL-1β, thereby promoting chondrocytic cell growth. In the present study, the OUMS-27 chondrocytic human chondrosarcoma cell line was treated with IL-1β with or without inhibitors of NF-κB signaling pathways. Chromatin immunoprecipitation (ChIP) and electromobility shift assays (EMSA) were conducted order to analyze the binding of NF-κB with the ADAMTS9 promoter region. NF-κB-p65 subunit phosphorylation was promoted in IL-1β-treated cells, which were not treated with inhibitors of NF-κB signaling pathways. By contrast, NF-κB-p65 subunit phosphorylation was inhibited in cells that had been treated with BAY-117085, an NF-κB pathway inhibitor. ChIP and EMSA assays demonstrated that, following treatment with IL-1β, NF-κB‑p65 bound to elements located at -1177 and -1335 in the ADAMTS9 promoter region, in contrast to the untreated samples. The results of the present study suggested that NF-κB may be involved in IL-1β-induced activation of ADAMTS9 in human chondrocytes.