Serum insulin-like growth factor-1 levels in patients with pseudoexfoliation syndrome and glaucoma.

Insulin-like growth factor-1 (IGF-1) is altered in several neurodegenerative diseases, the association between serum IGF-1 levels and glaucoma has not been evaluated. This study was designed to evaluate whether serum IGF-1 levels are different in patients with Pseudoexfoliation (PEX) with or without glaucoma. The study was conducted with 110 participants aged 65 years or older who were divided into three groups: group 1, patients with PEX syndrome; group 2, patients with PEX glaucoma; and group 3, participants without PEX or glaucoma. All participants underwent full ophthalmological examination and a detailed medical history was recorded. Patients with known neurodegenerative diseases other than PEX glaucoma were excluded. Serum IGF-1 levels were measured by automated chemiluminescent assay. Groups 1, 2, and 3 included 35, 34, and 41 patients, respectively; there were no differences regarding age, gender, or systemic disease status. There were also no statistically significant differences between the groups in terms of IGF-1 levels, which were 91.7 ± 39.1, 101.1 ± 40.2, and 107.2 ± 43.8 ng/ml for groups 1, 2, and 3, respectively (p = 0.276). Serum IGF-1 levels were similar by gender, the presence of systemic disease, status of diabetes mellitus, and laterality of the PEX material. There was no correlation between the cup-to-disk ratios and IGF-1 levels (r = -0.214, p = 0.223). IGF-1 levels in the circulation did not differ in the presence of PEX syndrome with or without glaucoma. This may indicate that the neurodegenerative process is local rather than systemic.

Evaluation of the Tosoh G8 Analyzer and Comparison with the Trinity Biotech Premier Hb9210 Analyzer for the Measurement of HbA1c.

BACKGROUND: The aim of our study was to assess the analytical performance of the Tosoh HLC-723G8 automated analyzer and to compare it with the Trinity Biotech Premier Hb9210 analyzer for the measurement of hemoglobin A1c (HbA1c). METHODS: A total of 101 patients with pre-diabetes or diabetes mellitus were included in the study. HbA1c, was measured by both an ion-exchange high-performance liquid chromatography (IE-HPLC) method and a boronate affinity chromatography method. Statistical analysis was performed using Deming regression. Bland-Altman plots were used to calculate mean difference (bias). RESULTS: The CV% values of IE-HPLC and boronate affinity methods for within run and between days were lower than 2.0%. High correlation was found (y = 1.0045x + 0.2111; r = 0.9941) between the two methods. The method shows no interference from carbamylated hemoglobin. CONCLUSIONS: Both systems showed acceptable performance and are suitable for clinical application in the analysis of HbA1c. However, laboratories should be aware of the limitations of their methods and the availability of more accurate and precise HbA1c, determination methods.

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.