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Open access

Jelena Jordovic, Ksenija Bojovic, Jasmina Simonovic-Babic, Vladimir Gasic, Nikola Kotur, Branka Zukic, Marija Vukovic, Sonja Pavlovic, Ivana Lazarevic, Ivana Bekic, Natasa Nikolic, Aleksandar Uroševic, Nikola Mitrovic and Dragan Delic


Background: Chronic hepatitis C (CHC) is a significant cause of liver related morbidity and mortality worldwide. The role of genetics in the host response to hepatitis C virus is not elucidated. Genetic variations in UGT1A1 gene are the most common cause of hereditary unconjugated hyperbilirubinemia-Gilbert syndrome. This is the first study investigating the association of UGT1A1 TA repeats promoter genotypes with the degree of liver injury, viremia and biochemical markers in CHC patients with advanced liver injury and late virological relapse.

Methods: Genetic testing of UGT1A1 TA repeats promoter genotypes was performed in 42 CHC patients with advanced fibrosis and cirrhosis who achieved sustained virological response and 42 healthy blood donors. CHC patients were evaluated for clinical findings, laboratory tests and imaging.

Results: UGT1A1*28 genotype (7/7 TA repeats) was observed in 23.8% CHC patients and 16.7% healthy controls with no significant difference in genotype frequencies (p=0.49). Pretreatment levels of ferritin and bilirubin were associated with the presence of UGT1A1*28 genotype, indicating its potential as a predictive marker. However, in our study, there was no correlation of UGT1A1*28 genotype with the degree of fibrosis or viremia. During antiviral treatment, dose reductions and treatment interruptions, as well as treatment success and occurrence of late virological relapse were not related to the presence of UGT1A1*28 genotype in CHC patients with severe liver injury.

Conclusions: Frequencies of UGT1A1*28 genotype are high in both Serbian CHC patients and healthy subjects. The presence of UGT1A1*28 genotype was not associated with ribavirin-related adverse effects and had no effect on long term outcome in CHC patients.

Open access

Biljana Bozic Nedeljkovic, Goran Loncar, Tjasa Vizin, Zoran Radojicic, Vera Popovic Brkic and Janko Kos


Background: The aim of the study was to investigate the association of Cystatin C (CysC) to biochemical markers of bone turnover and bone mass, and to evaluate its prognostic significance in elderly males with chronic heart failure (CHF).

Methods: A prospective cohort study was executed on sixtyeight males (mean age 68±7 years) with mild to moderate CHF, together with 19 of corresponding age- and body mass index-matched healthy individuals who underwent cardio vascular, bone mineral density (BMD), and body com position assessment. Biochemical assessment of all subjects included NT-pro-BNP, parathyroid hormone (PTH), 25-hydroxy vitamin D (25(OH)D), CysC, and biochemical markers of bone turnover including osteocalcin (OC), alkaline phosphatase (ALP), β-CrossLaps (β-CTx), osteoprotegerin (OPG), and receptor activator of nuclear factor κB ligand (RANKL).

Results: Serum CysC was significantly increased in males with CHF in comparison to healthy control ones. A significant positive association was found between CysC levels and OC in males with CHF, while OC and β-CTx increased in increasing CysC tertiles. In multivariate regression analysis, OC and smoking were a significant determinant of CysC in males with CHF. Level of CysC was found to be positively associated with an increased fatal risk in males with CHF.

Conclusions: Serum osteocalcin is an independent predictor of CysC level in elderly males with CHF. Higher CysC level showed a negative relation to survival and bone loss in males with CHF. Further research is needed to confirm the potential role of CysC in the crosstalk between heart, kidney, bone, and energy metabolism in CHF.

Open access

Tatjana Isailovic, Ivana Milicevic, Djuro Macut, Milan Petakov, Sanja Ognjanovic, Bojana Popovic, Ivana Bozic Antic, Tamara Bogavac, Valentina Elezovic Kovacevic, Dusan Ilic and Svetozar Damjanovic


Background: Multiple endocrine neoplasia type 1 (MEN1) is an autosomal dominant cancer syndrome characterized by the occurrence of primary hyperparathyroidism (PHPT), pituitary adenoma (PA) and pancreatic neuroendocrine tumor (pNET). Whether the underlying mutations in MEN1 gene predict clinical presentation of affected heterozygotes or not, is still a matter of a debate.

Methods: Clinical and genetic analysis of 90 consecutive MEN1 patients was performed in a retrospective, single – center study.

Results: MEN1 mutation was found in 67 (74.4%) patients belonging to 31 different families. Twenty nine different heteozygous mutations were found, including 6 novel point mutations (W220G, 941delG, 1088del7, 1184insA, 1473del10, 1602del17) and one large deletion of exon 8. Truncating mutations predicted development of pNETs (OR=5.8, 95% CI 1.7 – 19.7%) and PHPT (OR=4.3, 95% CI 1.5 – 12.4%).

Conclusions: Large number of novel mutations among MEN1 patients confirmed previously reported data. PNETs and PHPT were more frequent in patients with truncating mutations.

Open access

Nora Alyahri, Saba Abdi, Wajahatullah Khan, Mohamed Elrobh, Mohammed H. Addar, Zeneb A. Babay, Mohamed Alanazi, Sooad Aldaihan, Jilani Shaik, Maha Arafah, Narasimha Reddy Parine and Arjumand Warsy


Background: Mutations in BRCA1 gene have been implicated in ovarian cancers, and BRCA testing may be conducted in high-risk women. This study was designed to determine the frequency of three single nucleotide polymorphisms (SNPs) variants in BRCA1 gene and BRCA1 expression in Saudi females with ovarian cancer.

Methods: Expression levels of mRNA of BRCA1 gene were studied in 10 ovarian cancer and 10 normal ovarian tissues, by quantitative real time polymerase chain reaction (qPCR). The study also included 28 females who had suffered from ovarian cancer and had been successfully operated upon and 90 healthy females with no history of cancer. Blood was drawn in EDTA tubes and used for extraction of DNA. The genotyping was carried out using Taqman® SNP Genotyping kit by RT-PCR. The variants investigated included c.871 T>C (rs799917), c.1040 G>A (rs4986852), c.181 T>G (rs28897672) in BRCA1 gene.

Results: The c.181 T>G (rs28897672) showed significantly different genotype and allele frequencies between the patients and the control subjects (p value = 0.002 and 0.02, respectively). The genotype TG was significantly protective (OR = 0.36, p value = 0.024). The mRNA expression of BRCA1 gene was found to be low in the ovarian cancer tissues.

Conclusions: This study showed that c.181 T>G in BRCA1 genes is associated with the development of ovarian cancer in Saudis. More studies are needed to unveil other SNPs that may be associated with ovarian cancer and to understand the mechanism(s) involved in reducing the expression of BRCA1 gene in ovarian cancer tissues.

Open access

Milica Nedeljković, Nikola Tanić, Tatjana Dramićanin, Zorka Milovanović, Snežana Šušnjar, Vedrana Milinković, Ivana Vujović, Mirjana Prvanović and Nasta Tanić


Background: Triple negative breast cancer (TNBC) is characterized by aggressive clinical course and is unresponsive to anti-HER2 and endocrine therapy. TNBC is difficult to treat and is often lethal. Given the need to find new targets for therapy we explored clinicopathological significance of copy number gain of FGFR1 and c-MYC. Our aim was to determine the impact of FGFR1 and c-MYC copy number gain on clinical course and outcome of TNBC.

Methods: FGFR1 and c-MYC gene copy number alterations were evaluated in 78 archive TNBC samples using TaqMan based quantitative real time PCR assays.

Results: 50% of samples had increased c-MYC copy number. c-MYC copy number gain was associated with TNBC in contrast to ER positive cancers. Our results showed significant correlation between c-MYC copy number gain and high grade of TNBCs. This suggests that c-MYC copy number could be an useful prognostic marker for TNBC patients. c-MYC copy number gain was associated with high pTNM stage as well as lobular and medullary tumor subtypes. 43% of samples had increased FGFR1 copy number. No correlations between FGFR1 copy number gain and clinicopathological variables were observed.

Conclusions: We identified c-MYC copy number gain as a prognostic marker for TNBC. Our results indicate that c- MYC may contribute to TNBC progression. We observed no significant association between c-MYC and/or FGFR1 copy number status and patient survival.

Open access

Giray Bozkaya, Nuriye Uzuncan, Sibel Bilgili and Ozlem Demirezen


Background: Hemoglobin A1c, (HbA1c) which is the major constituent of glycated hemoglobin, has been used in the follow-up of retrospective glycemia for years and in the diagnosis of diabetes mellitus nowadays. Since the analytical performance of HbA1c should be high likewise all laboratory tests, various quality control measures are used. Sigma metrics is one of these measures and it is the combination of bias, precision and total allowable error that ensures a general evaluation of analytical quality. The aim of our study was to evaluate the analytical performance of Bio-Rad’s Variant Turbo II HbA1c analyzer according to sigma metrics.

Methods: Sigma levels were calculated using the data obtained from two levels of internal and 12 external quality control materials (Bio-Rad) of Variant II Turbo HbA1c analyzer according to s= (TEa% - Bias%) / CV% formula.

Results: The mean sigma levels for low and high quality control materials were found to be 3.0 and 4.1, respectively.

Conclusions: The annual mean analytical performance of Variant II Turbo HbA1c analyzer was found to be acceptable according to sigma metrics. In order to be sure of the difference in HbA1c results indicating the success or failure in treatment but not arise from analytical variation, it is thought that more stringent quality control measures should be applied to reach higher sigma levels.

Open access

Songül Ünüvar and Hamza Aslanhan


Background: Neopterin is a pyrazino-pyrimidine compound which is used as a marker of cell-mediated immunity in a variety of diseases. It is known that neopterin levels increase in diseases where interferon-gamma (IFN-g) stimulation is present, and also as a result of deficiencies in renal function, given that the primary means of elimination of neopterin is through the kidneys. In this study, we aimed to investigate the role of increased neopterin levels as a prognostic biomarker in patients with impaired renal function.

Methods: A total of 90 individuals including 63 patients with chronic kidney failure (CKF) and 27 healthy volunteers were included in the study. Serum neopterin concentrations were measured using the enzyme-linked immunosorbent assay. A Mann-Whitney U test and a Pearson Correlation Test were used in the statistical analysis, with a p value of <0.05 being considered statistically significant.

Results: The mean age was 52.21±0.16 years in the patient group and 56.55±0.32 years in the control group. In the CKF patients, serum neopterin levels increased to a significantly greater degree than in the control group (p<0.001), while no statistically significant correlation was identified between serum neopterin levels and age (p>0.05).

Conclusions: A significant increase was found in the serum neopterin levels in the CKF patients, due to both the triggering of the disease and the reduction of neopterin elimination.

Open access

Dušica Kocijančić Belovic, Snežana Plešinac, Jelena Dotlić, Ana Savić Radojević, Slavica Akšam, Mirjana Marjanović Cvjetićanin and Aleksandar Kocijančić


Background: Gestational hypertension (GH) and pre eclampsia (PE) are the most common gestational complications. Several placental biochemical markers are used to predict GH/PE, but with conflicting results.

Methods: The study aim was to estimate the biochemical markers’ ability to predict hypertensive disorders in pregnancy. On the first ultrasonographic examination, 104 healthy pregnant women were recruited. At the regular pregnancy check-ups, BMI, blood pressure, occurrence of gestational hypertension (early or late onset), preeclampsia, eclampsia and other complications were recorded. Serum concentrations (in multiples of median – MoM) of human chorionic gonadotropin (HCG) and pregnancyassociated plasma protein A (PAPPA) were measured from the 11th to 14th gestational week, while HCG, alpha feto protein (AFP), estriol and inhibin were determined between the 16th and 19th gestational week.

Results: Hypertensive disorders throughout pregnancy were diagnosed in 20.2% women. Early-onset GH was registered in 7 and PE in 6 patients, while 14 had late-onset GH and 10 additional women PE. There were no significant differences (p≥0.05) in biochemical markers concentrations between women with and without GH/PE. PAPPA levels in the first and HCG in the second trimester correlated with early and late GH/PE. Moreover, higher AFP concentrations were registered in women with preeclampsia signs/symptoms. According to ROC analysis, AFP>1.05 MoM properly identified 80% of GH/PE cases. Obtained models imply that HCG, PAPPA and AFP should be used for GH/PE prediction.

Conclusions: Biochemical markers HCG, PAPPA and AFP could be useful in predicting gestational hypertension and preeclampsia. However, different markers should be used for early and late onset GH/PE.

Open access

Najdana Gligorovic Barhanovic, Tanja Antunovic, Sreten Kavaric, Aleksandar Djogo and Vesna Kalimanovska Spasojevic


Background: Laboratory thyroid function tests play a central role in the diagnosis of thyroid disorders. The aim of our cross-sectional study was to determine reference values for thyroid tests in a rigorously selected group of Montenegrin females, investigate the impact of possible age-related changes and the influence of the interassay bias between three frequently used immunoassays.

Methods: Female subjects were randomly selected, aged between 20 and 69 and 946 of them met the selection criteria. TSH, fT3, fT4, thyroid peroxidase and thyroglobulin antibodies were measured. Eighty samples were further analyzed on two other immunochemistry platforms.

Results: Median TSH progressively increased with age, there was no difference in fT3, while fT4 was significantly higher in the two oldest groups compared to the others. When using the age-related 97.5 percentile of TSH the percentage of reclassification was highest in the 20–29 years of age group (5.2%, p<0.05). In the oldest band, 7.7% had TSH values above cohort-specific and below the age-related upper reference limit. Bland-Altman bias plots revealed the highest interassay absolute mean difference between compared TSH assays of 24.5% and for fT4 assays of 13.8%.

Conclusions: The correlation coefficients between fT3 assays from different manufacturers were low. Serum TSH and fT4 concentrations increased with age and the implementation of age-specific TSH reference intervals would be of interest. The bias between the three commercial immunoassays indicated that the standardization of thyroid function tests is a task of great importance.

Open access

Bojana Popovic, Dejana Popovic, Djuro Macut, Ivana Bozic Antic, Tatjana Isailovic, Sanja Ognjanovic, Tamara Bogavac, Valentina Elezovic Kovacevic, Dusan Ilic, Mirjana Petrovic and Svetozar Damjanovic


Background: Endocrine system plays a major role in both permissive and regulatory activities in order to adequately respond to physical stress of exercise. But level and direction of activation depend on many factors and are not easily interpreted.

Methods: We tested a group of male professional athletes (21 water polo players and 15 wrestlers), together with 20 sedentary controls matched by age. All participants took a continuous progressive exercise stress test on a treadmill until exhaustion and plateau of oxygen consumption (VO2). Blood samples for cortisol, sex hormone binding globulin (SHBG) and testosterone were drawn in four time points: baseline (B), start of the test (S), point of maximal strain (MAX) and in the 3rd minute of recovery period (R).

Results: Cortisol levels significantly increased in both groups, but the response between S and MAX was more pronounced in controls (p=0.036). The athletes had significantly higher levels of cortisol in all points in test, except during R (p=0.118), when their cortisol levels gradually started to decline. Significant increase in total testosterone was in great deal a consequence of increase in SHBG level (p<0.01 for both). Consequently, calculated free testosterone significantly decreased during test (p=0.008), and the drop was more pronounced in athletes. This was in concordance with significant correlation between SHBG and cortisol level demonstrated in athletes, but not in controls.

Conclusions: It seems that high intensity endurance exercise favors catabolic response, but the level of response highly depends on a previous level of training.