Comparison of Hemoglobin A1c assay performance on two different commercial systems

Introduction: Glycated hemoglobin (HbA1c) is formed by non-enzymatic binding of glucose to the free amino group of the N-terminal end of the ß-chain of hemoglobin A. HbA1c is representative of the mean blood glucose level over three months. The aim of the study was to evaluate the Hemoglobin A1c immunoturbidimetric assay performance on two different commercial systems.Methods: We evaluated the precision and trueness for determination of HbA1c in whole blood. Concentrations of total hemoglobin and HbA1c were evaluated on Dimension Xpand (Siemens) and Cobas 501 (Roche) analyzers. HbA1c was measured in a latex agglutination inhibition test. Commercial controls Liquichek Diabetes Control Level 1 and Liquichek Diabetes Control Level 2 (Bio Rad) at two levels were used for quality control. Analytical validation of HbA1c included: within-run imprecision, between-day imprecision, inaccuracy and comparison determination on the human samples on 2 systems: Dimension Xpand and Cobas 501 analyzers. Results: Within-run imprecision on the commercially controls for Level 1 is 4.5% and Level 2 is 3.2% between-day imprecision on commercially controls is 6.1% Level 1 and 5.1% Level 2 for respectively inac- curacy on commercially controls for Level 1 is 1.8% and Level 2 is 4.8%. Method comparison on human samples shows the correlation coefficient of 0.99.Conclusion: The presented results of the analytical evaluation methods for the determination of HbA1c showed an acceptable accuracy and precision

The Value of Serum Thyreoglobulin Levels and Whole Body (I-131) Scintigraphy in the Follow-Up of the Thyroid Cancer Patients after Thyroidectomy

Serum thyreoglobulin (Tg) and whole body scintigraphy (I-131 WBS) have been used to detect recurrent and metastatic thyroid cancers postoperatively. However, discordant results of Tg measurement and 131I WBS have been reported. Negative 131IWBS and a positive Tg test are usually found, but less common occurrence of positive 131IWBS and a negative Tg test has also been demonstrated in a small but significant number of cases. Therefore, the aim of the study was to retrospectively analyse patients with positive 131I WBS after total thyreoidectomy and again 1 year after the radioactive iodine. There were 52 patients included in the study. Four weeks after surgery, during which thyroid hormone treatment was not introduced, each patient received an ablative dose of 131I. The evaluation of the WBS was qualitative and considered positive if thyroid remnant, lymphatic node or metastasis were detected. WBS and serum Tg was measured 12 months after 131I ablation with thyroid hormone suppression. We considered positive any Tg level above the sensitivity values and negative if lower than this level. Tg levels were related to the existence of a positive scan or a negative one. In our 52 WBS positive patients concordant positive Tg levels were observed in 42 patients while in 10 patients we found a negative Tg levels after the surgery. After 1-year follow-up, out of initially 42 concordant patients 8 patients showed remaining concordant positive Tg and WBS values. Discordant results were observed in 13 patients (4 patients were Tgand WBS+ while 9 patients were Tg+ and WBS-). In the majority of patients (50%) remained with concordant results but changed from Tg+ and WBS+ to Tg- and WBS-. Diagnostic WBS is an additional valuable tool, besides Tg levels, in the follow up of patients after total thyreoidectomy

Importance of Measurement of Thyroglobulin and Anti-Thyroglobulin Antibodies in Differentiated Thyroid Cancer

Differentiated thyroid cancers include papillary and follicular carcinomas, both originating from follicular epithelium. Treatment of choice is usually total or near total thyroidectomy, followed by ablative radioiodine 131I treatment, and by the long term administration of thyroid hormone. Despite its excellent prognosis, recurrent disease does occur in approximately 20–40% of patients. Guidelines for the follow-up management of differentiated thyroid cancer are commonly based on circulating thyrogobulin measurement in the complete absence of eutopic thyroid tissue. A retrospective review was conducted on 116 patients (66 papillary and 50 follicular carcinoma, mean age 51.2 years) who had undergone total or near total thyroidectomy and radioactive iodine remnant ablation. Serum thyroglobulin (Tg) and anti-thyroglobulin antibodies (TgAb) levels were measured preoperatively, 1 month after thyroidectomy (before 131I treatment) and 6 and 12 months after ablation therapy (Tg1, TgAb1 and Tg2, TgAb2, respectively). During one year of follow-up, in a total of 24 patients (21%) recurrent disease were confirmed by ultrasonography and whole-body-scanning, mostly. It was found significant correlation between serum Tg levels (measured preoperatively and postoperatively) and recurrent diseases (p<0.05), while serum TgAb levels did not have any statistical significance. However, in multivariate regression analysis only Tg levels measured 12 months after the therapy (Tg2) remained a significant predictor of recurrent disease (p=0.008). Although a high Tg level before surgery does not indicate that tumor is present, in the postoperative period and after ablative therapy Tg has proven predictive value because stimulated Tg levels above 10ng/ml confirmed that indicate residual or recurrent cancer, and its periodically measurements is recommended

ASSOCIATION OF NEUROPEPTIDE S RECEPTOR 1 AND GLUTAMATE DECARBOXYLASE 1 GENE POLYMORPHISMS WITH POSTTRAUMATIC STRESS DISORDER

Background: Posttraumatic stress disorder (PTSD) is an anxiety disorder caused by highly traumatic experiences. The aim of this study was to investigate the influence of single nucleotide polymorphisms (SNPs) in the neuropeptide S receptor 1 (NPSR1) and the glutamate decarboxylase 1(GAD1) gene on PTSD and its psychopathological aspects among individuals affected by the Balkan wars during the 90s. Subjects and methods: This study was conducted as part of the South Eastern Europe (SEE) study on molecular mechanisms of PTSD. It comprised 719 participants (539 males), including those with current PTSD, remitted PTSD and healthy volunteers. Psychometric evaluation was performed using the Mini International Neuropsychiatric Interview (M.I.N.I.), the Clinician Administrated PTSD Scale (CAPS) andthe Brief Symptom Inventory (BSI). We examined NPSR1 single nucleotide polymorphism (SNP) rs324981 and GAD1 variant rs3749034 genotypes. Case-control analyses were carried out using logistical regression to determine genotype differences between all patients that had either current or remitted PTSD and control individuals. To analyse the influence of the analysed SNPs on PTSD severity, we performed linear regression analyses with CAPS and BSI within each of the two patient groups separately. All of the calculations were performed for additive allelic, recessive, dominant and genotypic models. Results: We observed a nominally significant association for the major allele (G) of GAD1 rs3749034 with an increased risk to develop PTSD in a case control analysis in the recessive model (P=0.0315, odds ratio=0.47, SE=0.35). In contrast, a nominally significant association of the minor allele (A) with higher CAPS scores was identified within the patient group with lifetime PTSD in the dominant model (P=0.0372, ????=6.29, SE=2.99). None of these results did withstand correction for multiple tests. No nominal significant results of GAD1 rs3749034 were found with regard to the intensity of psychological BSI symptoms. Case control analyses of NPSR1 rs324981 revealed a nominally significant higher risk for homozygous T allele carriers to develop PTSD (P=0.0452) in the recessive model. On the other hand, the T allele showed a nominally significant association with higher BSI scores in patients suffering from lifetime PTSD in the recessive model (P=0.0434). Again, these results were not significant anymore after correction for multiple tests. No associations of NPSR1 rs324981 and CAPS score was identified. Conclusion: The findings of this study provide some evidence that the NPSR1 and GAD1 polymorphisms might play a role in the development of war-related PTSD and its related psychological expressions. Further research is needed to elucidate the interactions of specific gene variants and environmental factors in the development of PTSD

ASSOCIATIONS OF GENE VARIATIONS IN NEUROPEPTIDE Y AND BRAIN DERIVED NEUROTROPHIC FACTOR GENES WITH POSTTRAUMATIC STRESS DISORDER

Background: Individuals who are exposed to traumatic events are at an increased risk of developing posttraumatic stress disorder (PTSD), a condition during which an individual\u27s ability to function is impaired by emotional responses to memories of those events. The gene coding for neuropeptide Y (NPY) and the gene coding for brain-derived neurotrophic factor (BDNF) are among the number of candidate gene variants that have been identified as potential contributors to PTSD. The aim of this study was to investigate the association between NPY and BDNF and PTSD in individuals who experienced war-related trauma in the South Eastern Europe (SEE) conflicts (1991-1999). Subjects and methods: This study included participants with current and remitted PTSD and healthy volunteers (N=719, 232 females, 487 males), who were recruited between 2013 and 2015 within the framework of the South Eastern Europe (SEE) - PTSD Study. Psychometric methods comprised the Mini International Neuropsychiatric Interview (M.I.N.I.), the Clinician Administered PTSD Scale (CAPS), and the Brief Symptom Inventory (BSI). DNA was isolated from whole blood and genotyped for NPY rs5574 via PCR - RFLP and NPY rs16147 and BDNF rs6265 using the KASP assay. Results: Tests for deviation from Hardy-Weinberg equilibrium showed no significant results. Analyses at the categorical level yielded no associations between the affected individuals and all three SNPs when compared to controls. Within lifetime PTSD patients, the major alleles of both NPY variants showed a nominally significant association with higher CAPS scores (p=0.007 and p=0.02, respectively). Also, the major allele of rs5574C>T was associated with higher BSI scores with a nominal significance among current PTSD patients (p=0.047). The results did not withstand a Bonferroni adjustment (????=0.002). Conclusion: Nominally significant associations between NPY polymorphisms and PTSD susceptibility were found that did not withstand Bonferroni correction

A CANDIDATE GENE ASSOCIATION STUDY OF FKBP5 AND CRHR1 POLYMORPHISMS IN RELATION TO WAR-RELATED POSTTRAUMATIC STRESS DISORDER

Background: Posttraumatic stress disorder (PTSD) is a highly frequent and disabling psychiatric condition among war-affected populations. TheFK506-binding protein 5 (FKBP5) gene and the corticotropin releasing hormone receptor 1 (CRHR1) gene have previously been implicated in an elevated risk of peritraumatic dissociation and PTSD development. Our aim was to investigate the association between FKBP5 and CRHR1 genotypes and PTSD diagnosis and severity among individuals who were affected by the Balkan wars during the 1990s. Subjects and methods: This study included participants with current PTSD, remitted PTSD and healthy volunteers (N=719, 487 males), who were recruited between 2013 and 2015 within the framework of the South Eastern Europe (SEE) - PTSD Study. Psychometric methods comprised the Mini International Neuropsychiatric Interview (M.I.N.I.), the Clinician Administrated PTSD Scale (CAPS), and the Brief Symptom Inventory (BSI). FKBP5 rs1360780 and CRHR1 rs17689918 genotypes were determined using a KASP genotyping assay. Results: Tests for deviation from Hardy Weinberg equilibrium showed no significant results. Logistic and linear regression was used to examine the associations between the FKBP5 SNP rs1360780 and the CRHR1 SNP rs17689918 with PTSD diagnosis and severity, as well as general psychiatric symptom severity, separately for current and remitted PTSD patients. There were nominally significant associations under a dominant model between the rs1360780 C allele and PTSD diagnosis as well as symptom severity, which however, were not significant anymore after Bonferroni adjustment (????=0.002). For CRHR1 rs17689918 no significant associations were detected. Conclusion: We found nominally, but not Bonferroni corrected significant associations between the FKBP5 polymorphism rs1360780 and PTSD susceptibility among individuals affected by the Balkan wars. For elucidating this gene’s real resilience/ vulnerability potential, environmental influences should be taken into account

THE ASSOCIATION OF CATECHOL-O-METHYL-TRANSFERASE AND INTERLEUKIN 6 GENE POLYMORPHISMS WITH POSTTRAUMATIC STRESS DISORDER

Background: Posttraumatic stress disorder (PTSD) is a disorder that occurs in some people who have experienced a severe traumatic event. Several genetic studies suggest that gene encoding proteins of catechol O-methyl-transferase (COMT) may be relevant for the pathogenesis of PTSD. Some researchers suggested that the elevation of interleukin-6 (IL6) correlates with major depression and PTSD. The aim of this study was to investigate whether the single nucleotide polymorphisms COMT rs4680 (Val158Met) and IL6 rs1800795 are associated with PTSD and contribute to the severity of PTSD symptoms. Subjects and methods: This study comprised 747 participants that experienced war between 1991 and 1999 in the South Eastern Europe conflicts. COMT rs4680 (Val158Met) and IL6 rs1800795 genotypes were determined in 719 participants (369 with and 350 without PTSD). The Mini International Neuropsychiatric Interview (M.I.N.I.), the Clinician Administrated PTSD Scale (CAPS) questionnaire and the Brief Symptom Inventory (BSI) were used for data collection. Results: Regarding the COMT gene polymorphism, the results of the regression analyses for BSI total score were significant in the lifetime PTSD group in the dominant (P=0.031) and the additive allelic model (P=0.047). Regarding the IL6 gene, a significant difference was found for the recessive model predicting CAPS total score in the lifetime PTSD group (P=0.048), and indicated an association between the C allele and higher CAPS scores. n the allelic, genotypic and rezessive model, the results for BSI total score were significant in the lifetime PTSD group (P=0.033, P=0.028 and P=0.009), suggesting a correlation of the C allele with higher BSI scores Conclusion: Although our nominally significant results did not withstand correction for multiple tests they may support a relevance of the COMT (Val158Met) and IL6 rs1800795 polymorphism for aspects of PTSD in war traumatized individuals

ASSOCIATION ANALYSIS OF MAOA AND SLC6A4 GENE VARIATION IN SOUTH EAST EUROPEAN WAR RELATED POSTTRAUMATIC STRESS DISORDER

Background: The aim of this study is to investigate the association of gene variations of the monoamine oxidase A (MAOA) and the serotonin transporter solute carrier family 6 member 4 (SLC6A4) gene with posttraumatic stress disorder (PTSD) severity and coping strategies in patients with war related PTSD. Subjects and methods: The study included 747 individuals who had experienced war trauma in the South Eastern Europe conflicts between 1991 and 1999. Genotyping of the MAOA VNTR and SLC6A4 tandem repeat polymorphism in combination with rs25531 was done in 719 participants: 232 females and 487 males. Among them, 369 have had current or lifetime PTSD and 350 have had no PTSD symptoms. For psychometric approach we used the Clinician Administrated PTSD Scale (CAPS), the Brief Symptom Inventory (BSI), the adapted Hoffman Lazarus Coping scale and a basic socio-demographic data questionnaire. Results: There were no significant intergroup (PTSD versus non PTSD) differences in the genotype distribution of MAOA and SLC6A4 gene polymorphisms. The primary finding of our study was that the MAOA short allele (MAOA-S) was nominally significantly associated with the severity of PTSD symptoms in the total subgroup of participants with lifetime PTSD; males for symptoms of hyperarrousal and females with symptoms of re-experience and hyperarousal. In our research the male subsample with current PTSD and MAOA-S genotype had nominally significantly higher scores for some positive coping strategies compared to those carrying the long allele genotype (MAOA-L). There was no significant association between the severity of PTSD symptoms, BSI phenotype, coping scores and the SLC6A4 genotype. Conclusion: The present results support the notion that MAOA VNTR gene variation modulates development and recovery of posttraumatic stress disorder in a war traumatised population, but did not support a connection between SLC6A4 gene variations and war related PTSD

GENETIC SUSCEPTIBILITY TO POSTTRAUMATIC STRESS DISORDER: ANALYSES OF THE OXYTOCIN RECEPTOR, RETINOIC ACID RECEPTOR-RELATED ORPHAN RECEPTOR A AND CANNABINOID RECEPTOR 1 GENES

Background: Exposure to life-threatening events is common and everyone will most likely experience this type of trauma during their ifetime. Reactions to these events are highly heterogeneous and seems to be influenced by genes as well. Some individuals will develop posttraumatic stress disorder (PTSD), while others will not. In this study, our aim was to analyze the correlation between single nucleotide polymorphisms (SNPs) within the oxytocin receptor (OXTR) gene (rs53576 and rs2254298), the RAR-related orphan receptor A (RORA) gene (rs8042149) and the cannabinoid receptor 1 (CNR1) gene (rs1049353) and PTSD. All candidate genes have been previously associated with stress related disorders and the reaction to traumatic events. Subjects and methods: Participants (N=719) have been exposed to war-related trauma during the war in South-Eastern Europe (Bosnia and Herzegovina, Croatia and Kosovo). We correlated the presence and absence of current and lifetime PTSD as well as PTSD severity (Clinician Administered PTSD scale (CAPS)) and current psychopathology (Brief Symptom Inventory (BSI) score) with the mentioned SNPs. DNA was isolated from whole blood and genotyped for OXTR rs2254298 and rs53576 following previously published protocols, for RORA rs8042149 via PCR-RFLP and CNR1 rs1049353 via KASP. Results: Nominally significant results were found for OXTR rs53576 in connection with the CAPS and BSI scores within lifetime PTSD patients. The additive allelic model indicated that G allele carriers achieved lower CAPS (p=0.0090) and BSI (p=0.0408) scores than participants carrying one or two copies of the A allele. These results did not withstand correction for multiple tests. No significant results were observed for OXTR rs2254298, RORA rs8042149 and CNR1 rs1049353 although the results for RORA showed a slight tendency that rs8042149 may influence the level of BSI scores in current PTSD patients. Conclusions: This study points to a role of the OXTR gene in PTSD and the related psychopathology following war related trauma

The utility of procollagen type 1 N-terminal propeptide for the bone status assessment in postmenopausal women

The utility of procollagen type 1 N-terminal propeptide (P1NP) in the management of metabolic bone diseases remains a subject of debate since the reference ranges are not rigorously established and fail to account for many of the preanalytical variables. We aimed to establish reference intervals for P1NP level in healthy and osteoporotic postmenopausal females stratified by age, body mass index and menopausal duration. We also aimed to assess the relationship between P1NP and BMD. This cross-sectional study enrolled 183 postmenopausal females who were divided in osteoporosis group (N=93) and control group (N=90) with preserved bone mass based on BMD assessed by DXA. In the osteoporosis group median P1NP was significantly higher (51.7 ng / mL; 95%CI 43.2-53.7) compared to control group (38.9 ng/mL; 95%CI 34.2-43.9)(p<0.01). After controlling for age, BMI and years since menopause, there was significant inverse association between BMD and P1NP at the femoral neck (r=-0.18), total hip (r=-0.207) and lumbar spine (r=-0.236). There was no significant difference in P1NP concentration across quartiles of age in postmenopausal females. P1NP was significantly lower in obese postmenopausal females with preserved bone mass compared to normal weight and overweight females in control and in osteoporosis group. In conclusion, we showed that P1NP is inversely associated with BMD even after controlling for age, BMI and years since menopause. Although, P1NP is significantly higher in postmenopausal females with osteoporosis compared to postmenopausal females with preserved bone mass its low specificity does not warrant its utility is diagnosing osteoporosis