ABSTRACT
In this study, simple, fast and reliable cyclic voltammetry, linear sweep voltammetry, square wave voltammetry and differential pulse voltammetry methods were developed and validated for determination of etodolac in pharmaceutical preparations. The proposed methods were based on electrochemical oxidation of etodolac at platinum electrode in acetonitrile solution containing 0.1 M lithium perchlorate. The well-defined oxidation peak was observed at 1.03 V. The calibration curves were linear for etodolac at the concentration range of 2.5-50 µg/ml for linear sweep, square wave and differential pulse voltammetry methods, respectively. Intra- and inter-day precision values for etodolac were less than 4.69, and accuracy (relative error) was better than 2.00%. The mean recovery of etodolac was 100.6% for pharmaceutical preparations. No interference was found from three tablet excipients at the selected assay conditions. Developed methods in this study are accurate, precise and can be easily applied to Etol, Tadolak and Etodin tablets as pharmaceutical preparation.
ABSTRACT
BACKGROUND: To examine the differences in intraocular pressure (IOP) measurements obtained with Goldmann applanation tonometry (GAT) and Pascal dynamic contour tonometry (DCT) in subjects with thin corneas and to correlate these with structural and functional parameters of glaucoma damage. PATIENTS AND METHODS: One hundred and thirty participants (130 eyes) with central corneal thickness lower than 500 µm were included in five groups in this cross-sectional observational study: 52 eyes with primary open angle glaucoma (POAG), 19 eyes with normal tension glaucoma (NTG), 27 eyes with ocular hypertension (OHT), 21 participants suspected of having glaucoma (GS), and 11 healthy subjects. The measurements were obtained with GAT and DCT in a masked fashion. The corrected GAT-IOP for central corneal thickness (CCT), the difference between DCT and GAT (ΔIOP = DCT-GAT) and corrected ΔIOP (corrected ΔIOP = DCT-corrected GAT) were calculated. Age, mean deviation (MD) from the most recent reliable visual field examination, average retinal nerve fibre layer thickness (RNFL), cup-to-disc ratio (CDR), ocular pulse amplitude (OPA), and treatment status were recorded for statistical analysis. RESULTS: In all of the subjects (n = 130), the mean DCT, GAT and corrected GAT values were 17.6 ± 3.4 mmHg, 13.2 ± 3.8 mmHg, and 15.5 ± 2.1 mmHg, respectively. ΔIOP and corrected ΔIOP were 4.4 ± 2 mmHg and 1.7 ± 2 mmHg, respectively. ΔIOP was correlated negatively with MD (rs = -0.32, p < 0.0001) and average RNFL thickness (r = -0.46, p < 0.0001) and positively with CDR (rs = 0.50, p < 0.0001). The mean IOP measured by GAT differed statistically significantly between eyes with glaucoma (n = 71, POAG and NTG) and eyes without damage (n = 59; OHT, GS, and healthy) (p < 0.0001), whereas the mean IOP by DCT did not (p = 0.935). The mean ΔIOP values were also statistically significantly higher in the glaucomatous group, with and without correction for CCT (p < 0.001). OPA and glaucoma diagnoses statistically significantly predicted ΔIOP (R(2) = 0.41, F2.127 = 47.46, p < 0.0001). CONCLUSION: Greater underestimation of IOP by GAT was observed in the glaucomatous eyes with thin corneas. Performing DCT on patients with thin corneas might be advantageous in establishing the need for more aggressive treatment.
Subject(s)
Cornea/physiopathology , Glaucoma/diagnosis , Glaucoma/physiopathology , Intraocular Pressure , Aged , Cornea/pathology , Female , Glaucoma/pathology , Humans , Male , Middle Aged , Reproducibility of Results , Sensitivity and Specificity , Tonometry, OcularABSTRACT
BACKGROUND: Prostate specific antigen (PSA) is the most important biochemical marker in the diagnosis and follow-up of patients with prostate cancer. In recent years, a relationship between PSA levels and cardiovascular conditions has been described. However, no study has investigated the PSA levels after coronary stenting. AIM: To investigate the impact of coronary stent implantation on serum total PSA (tPSA) and free PSA (fPSA) levels. METHODS: This study involved 60 men who underwent coronary angiography for suspected coronary artery disease. Of these, 25 were diagnosed as having angiographically normal coronary arteries (Group 1) and 35 underwent coronary stent implantation (Group 2). Serum tPSA and fPSA levels and f/tPSA ratios were determined in all patients immediately before the intervention and 24 hours and 30 days after the procedure. RESULTS: In Group 1, there was no statistically significant change in the values of tPSA, fPSA and f/tPSA ratio before and after coronary angiography (p >0.05). In Group 2, tPSA and fPSA values 24 hours after stent implantation were significantly higher than the values at the baseline (p <0.01), whereas f/tPSA ratio did not change (p >0.05). Compared with the baseline, there was no statistically significantly difference in the PSA values 30 days after stent implantation (p >0.05). CONCLUSIONS: This study demonstrated that serum tPSA and fPSA levels are increased after coronary stent implantation, but f/tPSA ratio is not affected. The findings suggest that serum tPSA and fPSA levels should not be used for the diagnosis of prostate cancer during the first 30 days after coronary stenting.