Sialic acid content in erythrocyte membranes of patients on chronic hemodialysis.

INTRODUCTION: Sialic acids (SA) located in erythrocyte membranes (EM) play an important role in the survival of circulating red blood cells. OBJECTIVES: The aim of the present study was to evaluate the SA content in EM obtained from patients on chronic hemodialysis (HD) and to examine the relationships between SA and hematological parameters. Moreover, the effects of HD, treatment with human recombinant erythropoetin (epoetin), and some biochemical and hematological parameters were analyzed. PATIENTS AND METHODS: The total protein (TP) and total sialic acids (TSA), together with SA bound with proteins (PBSA) and lipids (LBSA), were determined in EM of 72 HD patients and compared with the control group of healthy individuals (CG; n=25). The adequacy of HD, weekly epoetin doses, mean arterial pressure (MAP), comorbidity score, serum levels of albumin, intact parathyroid hormone (iPTH), low-density lipoprotein cholesterol (LDL-cholesterol) were estimated in patients. RESULTS: Compared to the CG, HD patients had higher levels of TSA (p < 0.001), PBSA (p < 0.001), LBSA (p <0.001) and decreased TP levels (p < 0.001). The TP (p < 0.045) and PBSA (p < 0.05) levels were higher in patients with diabetic nephropathy than in non-diabetic HD patients. In HD patients there were correlations between TSA, PBSA in EM and some hematologial parameters. There were no relationships between the TSA, PB content in EM and variables such as HD, epoetin treatment, MAP comorbidity score, albumin, iPTH, and LDL-cholesterol. CONCLUSIONS: The results of the current study demonstrated there are significantly higher levels of TSA, PBSA, LBSA and lower TP levels in EM obtained from HD patients compared to healthy subjects. Comorbidity score, epoetin and HD treatment, MAP, iPTH, albumin and LDL cholesterol had no influence on SA levels in EM of patients.

The level of alpha-antitrypsin and ceruloplasmin in the subretinal fluid of patients with rhegmatogenous retinal detachment.

UNLABELLED: The aim of the study was to determine alpha-antitrypsin (AAT) and ceruloplasmin (CER) level in the subretinal fluid of patients with rhegmatogenous retinal detachment (RRD). Investigation was performed in 41 patients (22 women, 19 men) operated on for RRD at the age from 24 to 81. The group of patients was divided with regard to the extent and duration of RRD. In 24 patients detachment involved 1 or 2 quadrants and in 17 patients--3 or 4 quadrants. In 16 subjects RRD lasted shorter than 2 weeks, in 6 patients--about one month and in 19 patients--from 1 to 3 months. The subretinal fluid was collected during operation. The levels of the examined substances were determined with the radial diffusion method on Nor-Partigen plates by Behring. The results were as follows: mean AAT concentration in the subretinal fluid of all the patients operated on for RRD was 0.739 +/- 0.475 g/l and CER was 0.186 +/- 0.122 g/l. Mean AAT concentrations did not differ statistically significantly between the group with bigger and smaller retinal detachments while CER level was higher in the group with a bigger RRD. Mean AAT and the CER concentration was statistically significantly higher in the group with RRD lasting from 1 to 3 months compared with the group with RRD lasting shorter than one month. CONCLUSIONS: the fact of finding acute phase proteins in subretinal fluid suggests that they may play a part in the pathogenesis of RRD by affecting the intensity of local inflammatory reaction.

The level of total sialic acid, alfa-antitrypsin, ceruloplasmin in the serum of patients with choroidal melanoma.

Melanoma of the choroid is a fatal disease because of its metastases. The quest is ongoing for more reliable serum markers for detecting and staging ocular melanoma. Total serum sialic acid and acute phase proteins are valuable adjuncts in the management of malignancies, including melanoma. The aim of the paper was to asses the level of total sialic acid (TSA), total sialic acid to total protein (TP) ratio (TSA/TP) and the level of alfa-antitrypsin (AAT) and ceruloplasmin (CER) in patients with choroidal melanoma. The concentrations of TSA, TP, AAT and CER were evaluated in 61 patients with choroidal melanoma and 84 healthy controls. 36 patients had larger tumors and 25 patients had smaller melanomas. 36 patients were treated with brachytherapy. The mean concentration of TSA in all intraocular melanoma patients was 84.86 +/- 19.37 mg/dl and was significantly higher than in control group 53.63 +/- 8.47 mg/dl (p < 0.001). TSA level was significantly higher in patients with large tumors than in those with smaller choroidal melanomas. There were not differences between groups of patients treated with brachy-therapy and those not treated. TSA/TP in melanoma patients was 11.88 +/- 2.97 and it was higher than in control group 7.32 +/- 1.21 (p < 0.001). AAT level was 236.56 +/- 141.53 mg/dl in the group of melanoma patients and in the control group was 226.42 +/- 46.74 mg/dl but the differences were not statistically significant. The concentration of CER in the study group was 28.25 +/- 11.01 mg/dl and in the control group it was 29.56 + 6.33 mg/dl but the differences were not statistically significant. The assessment of TSA in blood serum may be useful in evaluation of patients with choroidal melanoma.