Performance of different screening methods for the determination of urinary glycosaminoclycans

BACKGROUND

The study aim was to compare the performance of three different methods used for determining urinary glycosaminoglycans (GAG) levels in spot and 24-h urine samples.

METHODS

Performance characteristics were studied for cetylpyridinium chloride (CPC), and manual and automated dimethylmethylene blue (DMB) methods.

RESULTS

For automated DMB method, within-run precisions were 9.10% and 1.98%, and between-day precisions were 13.0% and 5.81% in low- and high-urine pools, respectively. The method was linear up to 100 mg/L of GAG concentration. The detection limit of the method was 0.71 mg/L. Mean recovery was 95.7%.

CONCLUSIONS

The automated DMB method was found to give better performance characteristics than cetylpyridinium chloride (CPC) and manual DMB methods. It is a fast, cheap, simple and reliable method and can be applied in many diseases in which GAG is used as a screening test.

Cardiovascular risk factors in hemodialysis and peritoneal dialysis patients

BACKGROUND

Cardiovascular disease (CVD) is the major cause of mortality and morbidity of hemodialysis (HD) and peritoneal dialysis (CAPD) patients. We aimed to investigate the cardiovascular risk factors and their correlation with CVD in groups of HD and CAPD patients.

METHODS

Thirty HD patients, 30 CAPD patients and 30 healthy controls were included in the study. Apolipoprotein A-l (apo A-l), apolipoprotein B (apo B), apolipoprotein(a) [Lp(a)] and high-sensitivity CRP (hs-CRP) were measured with a Beckman Coulter nephelometer, and homocysteine (Hcy) was determined with an Agilent HPLC analyzer. Lipid profile was determined with a Synchron LX 20 Pro analyzer.

RESULTS

Hcy levels were 41.9+/-19.4, 41.8+/-38.5 and 9.3+/-3.5 micromol/L; Lp(a) levels were 325+/-315, 431+/-367 and 130+/-97 mg/L; hs-CRP levels were 3.78+/-3.21, 4.34+/-3.39 and 2.07+/-1.67 mg/L; apo A1/apo B ratios were 1.46+/-0.6, 1.36+/-0.5 and 1.80+/-0.59; total cholesterol levels were 3.56+/-0.7, 4.84+/-1.1 and 4.39+/-0.5 mmol/L; triglycerides were 1.44+/-0.5, 1.60+/-0.8 and 0.85+/-0.5 mmol/L in the HD, CAPD and control groups, respectively.

CONCLUSION

HD and CAPD patients had higher Hcy, hs-CRP and Lp(a) levels and lower apo A/B ratios than controls. There was no significant difference between the HD and CAPD groups. Hypertension, age and hs-CRP showed a positive correlation with CVD.

Prevention of selenite-induced cataractogenesis by N-acetylcysteine in rats

PURPOSE

To evaluate the effect of N-acetylcysteine on selenite-induced cataract formation in a rat model.

MATERIALS AND METHODS

Thirty-four Sprague-Dawley rat pups were divided into three groups. Eight pups received only selenite on postpartum day 10 (group 1), 14 pups received selenite on day 10 and additional acetylcysteine on postnatal days 9 to 15 (group 2), and 12 pups received only saline (group 3, control). All pups were daily examined for the presence of cataract under the microscope, starting from the day their eyes opened. Glutathione and malondialdehyde levels were evaluated in both serum and lenticular samples while protein carbonyl level was studied only in lenticular samples.

RESULTS

In group 1, 50% of the rats developed dense nuclear opacities and 50% developed slight nuclear opacities, while in group 2 only 14.3% developed dense nuclear opacities and 21.4% developed slight nuclear opacities (p < 0.05). None of the rats in group 3 developed any lens opacity. In lenticular samples, mean glutathione level was statistically lower in group 1 compared to groups 2 and 3 (p < 0.05), while malondialdehyde and protein carbonyl levels were both statistically higher in group 1 compared to groups 2 and 3 (p < 0.05). Serum level of glutathione was statistically lower in group 1 compared to groups 2 and 3 (p < 0.05), while serum malondialdehyde level was statistically lower in group 3 compared to groups 1 and 2.

CONCLUSIONS

N-acetylcysteine appears to inhibit selenite-induced cataractogenesis in the rat model, and this seems to be caused by the prevention of oxidative damage.

Association between nitric oxide and oxidative stress in continuous ambulatory peritoneal dialysis patients with peritonitis

BACKGROUND

Peritonitis is a major complication in continuous ambulatory peritoneal dialysis (CAPD) patients, and the mechanisms involved in the pathology are important if the success rate of treatment strategies is to increase.

MATERIAL AND METHODS

A total of 50 CAPD patients (25 with 25 episodes of peritonitis and 25 with no clinical or laboratory signs of infection) were included in the study. Malondialdehyde (MDA) and nitric oxide (NO) metabolites in serum and dialysate effluents were determined.

RESULTS

The dialysate/serum (D/S) ratio of the NO metabolites and serum NO metabolite concentrations were significantly higher in the peritonitis group. Serum and dialysate MDA concentrations were also significantly higher in the peritonitis group. The D/S ratio of MDA was significantly higher in the control group.

CONCLUSIONS

Local peritoneal NO production and oxidative stress seem to increase in CAPD patients during the peritonitis attack.