Interleukin-4 Gene Intron 3 VNTR Polymorphism in Type 2 Diabetes Patients with Peripheral Neuropathy.

OBJECTIVE: Diabetic peripheral neuropathy (DPN) is one of late complications of diabetes mellitus. The aim of this study was to evaluate the association between variable number tandem repeat (VNTR) polymorphism in intron 3 of interleukin-4 gene and risk of DPN. METHODS: We examined 926 T2DM patients and 420 healthy controls. In the patient group, 44% had DPN. Genomic DNA was isolated from all subjects and genotyped for the IL-4 VNTR polymorphism by polymerase chain reaction (PCR). RESULTS: No significant difference was observed in the frequency of minor P1 allele between T2DM patients and controls (OR 1.00, 95% CI 0.81-1.23, p = 0.988). The distribution of IL-4 VNTR polymorphism was compared between patients with DPN and those without it. The polymorphism was not significantly associated with DPN in studied subjects. In comparison of 406 T2DM patients with DPN and 520 patients without it, the OR (95% CI) for P1 allele was 0.82 (0.65-1.04), p = 0.10 and for P1P1 genotype 1.00 (0.53-1.89), p = 0.991. When two subgroups of patients with DPN, those with cardiovascular disease (CVD) and without CVD, were compared, subgroup with coexisting CVD had significantly higher frequency of P1 allele than patients without CVD, with odds ratio for the P1 allele 3.27 (95% CI 1.83-5.83), p = 0.0001. CONCLUSION: Our results demonstrated that VNTR polymorphism in the IL-4 gene is associated with DPN in type 2 diabetes patients with coexisting CVD.

Cholesteryl Ester Transfer Protein Gene Polymorphism (I405V) and Risk of Ischemic Stroke.

BACKGROUND: Cholesteryl ester transfer protein (CETP) plays a major role in the metabolism of high-density lipoprotein. Polymorphisms in the CEPT gene can affect susceptibility to atherosclerosis and cardiovascular disease. The aim of this study was to evaluate the association of the CETP I405V polymorphism with ischemic stroke. METHODS: Five hundred eighty stroke patients and 505 healthy controls were involved in a study. Genomic DNA from all subjects was genotyped for the I405V polymorphism by polymerase chain reaction and restriction analysis. RESULTS: The comparison of stroke and control groups showed a significant increase of V allele and VV genotype in stroke patients (OR 1.61, 95% CI 1.34-1.93 and 2.83, 95% CI 1.78-4.51, respectively). The distribution of alleles and genotypes was also compared between stroke patients with type 2 diabetes mellitus (T2DM) and patients without it. No statistically significant differences were observed between two subgroups. The OR for V allele was 1.15, 95% CI .91-1.46 and for VV genotype 1.25, 95% CI .73-2.15. In comparison of these subgroups separately with controls, the results were similar to obtained for entire STR group. When the distribution of I405V polymorphism in relation to T2DM was analyzed in subgroups of men (n = 296) and women (n = 284) no statistically significant differences were observed. CONCLUSION: Our results demonstrate that the I405V polymorphism in the CETP gene is strongly associated with ischemic stroke. The presence of T2DM did not affect this association. To our knowledge this is the first such association documented in Caucasian population.

Mechanical thrombectomy in acute stroke - Five years of experience in Poland.

OBJECTIVES: Mechanical thrombectomy (MT) is not reimbursed by the Polish public health system. We present a description of 5 years of experience with MT in acute stroke in Comprehensive Stroke Centers (CSCs) in Poland. METHODS AND RESULTS: We retrospectively analyzed the results of a structured questionnaire from 23 out of 25 identified CSCs and 22 data sets that include 61 clinical, radiological and outcome measures. RESULTS: Most of the CSCs (74%) were founded at University Hospitals and most (65.2%) work round the clock. In 78.3% of them, the working teams are composed of neurologists and neuro-radiologists. All CSCs perform CT and angio-CT before MT. In total 586 patients were subjected to MT and data from 531 of them were analyzed. Mean time laps from stroke onset to groin puncture was 250±99min. 90.3% of the studied patients had MT within 6h from stroke onset; 59.3% of them were treated with IV rt-PA prior to MT; 15.1% had IA rt-PA during MT and 4.7% - emergent stenting of a large vessel. M1 of MCA was occluded in 47.8% of cases. The Solitaire device was used in 53% of cases. Successful recanalization (TICI2b-TICI3) was achieved in 64.6% of cases and 53.4% of patients did not experience hemorrhagic transformation. Clinical improvement on discharge was noticed in 53.7% of cases, futile recanalization - in 30.7%, mRS of 0-2 - in 31.4% and mRS of 6 in 22% of cases. CONCLUSION: Our results can help harmonize standards for MT in Poland according to international guidelines.

Predictors of intracranial cerebral artery stenosis in patients before cardiac surgery and its impact on perioperative and long-term stroke risk.

BACKGROUND: The aim of this prospective study was to determine the prevalence of stenosis within intracranial and extracranial arteries in patients before coronary artery bypass surgery (CABG), to evaluate the influence of intracranial artery stenosis on neurological outcome and to identify preoperative risk factors for these patients. METHODS: One hundred and seventy-five patients (71% males, mean age=66.1) scheduled for CABG were enrolled for extracranial Doppler duplex sonography, transcranial color-coded duplex sonography (TCCS) and transcranial Doppler (TCD) examination. RESULTS: Twenty-six patients (14.7%) had extracranial stenosis or occlusion and 13 patients (7.3%) intracranial vascular disease. Six patients (3.5%) had both extra- and intracranial artery disease. The presence of peripheral artery disease and diabetes mellitus was a strong risk factor for extracranial artery stenosis but not for intracranial artery stenosis, which occurred independently also of typical atherosclerotic risk factors like age >70, male sex, hypertension, hyperlipidemia, hyperhomocysteinemia, smoking habit, obesity (BMI>30) and waist to hip ratio >1. Functional neurological outcome of the patients with intracranial arterial disease evaluated 7 days after CABG was the same as the patients without extra- and intracranial stenosis. However, 12-months neurological follow-up revealed significantly more ischemic strokes in patients with intracranial artery stenosis compared to patients without intracranial stenosis (p=0.015). CONCLUSION: The occurrence of intracranial artery stenosis in CABG patients cannot be predicted by well-known atherosclerotic risk factors and seems not to be associated with perioperative stroke.

Heat-shock protein gene polymorphisms and the risk of nephropathy in patients with Type 2 diabetes.

HSPs (heat-shock proteins) are molecular chaperones synthesized under stress conditions, and are involved in renal cell survival and matrix remodelling in acute and chronic renal diseases. In the present study, we investigated whether the HSP70 gene polymorphisms affect susceptibility to DN (diabetic nephropathy) in patients with T2DM (Type 2 diabetes mellitus). The study group consisted of 452 patients with nephropathy. Two control subgroups involved 340 healthy individuals and 132 patients with T2DM lasting > or =10 years who were free of nephropathy. Subjects were genotyped for the HSP70-1 +190 G/C and -110 A/C, HSP70-2 +1267 A/G and HSP70-hom +2437 T/C polymorphisms by PCR, followed by digestion with restriction endonucleases. There were no statistically significant differences in genotype distribution between patients with T2DM with DN and controls for the HSP70-hom polymorphism. Significant differences were observed for HSP70-1 and HSP70-2 polymorphisms. CC homozygotes of the -110 and +190 HSP70-1 polymorphisms were more frequent in patients with T2DM with DN compared with healthy controls (22 compared with 6% and 15 compared with 6.5% respectively; P<0.01). The OR (odds ratio) for the risk allele was 2.17 [95% CI (confidence interval), 1.73-2.72] for the -110 A/C and 1.74 (95% CI, 1.40-2.15) for +190 G/C polymorphisms. A strong association with DN was found for the +1267 HSP70-2 polymorphism. The GG genotype and the G allele were associated with DN, with the OR for the G allele being 4.77 (95% CI, 3.81-5.96). All GG homozygotes in the patient group had higher LDL (low-density lipoprotein)-cholesterol levels than AA homozygotes (P<0.01), suggesting that the observed effect might be associated with this cardiovascular risk factor. These patients progressed faster to end-stage renal failure than those with other genotypes. In conclusion, our results indicate that the HSP70-1 and HSP70-2 polymorphisms are associated with renal complications in T2DM and may be useful in identifying patients with increased risk of DN.

Monocyte chemoattractant protein-1 (MCP-1) gene polymorphism as a potential risk factor for cardiovascular disease in hemodialyzed patients.

AIM: Polymorphism in the monocyte chemoattractant protein-1 (MCP-1) gene (A-2518G) has been associated with functional effects. The aim of the present study was to assess the effect of this polymorphism on end-stage renal disease (ESRD) and cardiovascular disease (CVD) in hemodialyzed patients. METHODS: A total of 720 patients with ESRD treated with hemodialysis (450 patients with CVD) and 325 healthy control subjects were genotyped for the MCP-1 -2518 polymorphism by the polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) procedure. RESULTS: There was a significant difference in genotype frequencies between entire group of hemodialyzed patients and controls (p<0.01). The odds ratio for the risk allele was 1.85, 95% CI 1.49-2.32 (p<0.01). Hemodialyzed patients were divided into subgroups with CVD (n=450) and without CVD (n=270). The G allele carriers occurred with significantly higher frequency in patients with CVD (62% vs. 38% in patients without CVD and 36% in controls). The odds ratio for the risk allele for patients with CVD vs. those without CVD was 2.17, 95% CI 1.71-2.79. There was no statistically significant difference in the distribution of MCP-1 genotypes between ESRD patients without CVD and healthy controls. CONCLUSION: Our results demonstrate for the first time an association between the polymorphism in the regulatory region of the MCP-1 gene and susceptibility to CVD in hemodialyzed patients.

Pro198Leu Polymorphism in the Glutathione Peroxidase 1 Gene Contributes to Diabetic Peripheral Neuropathy in Type 2 Diabetes Patients.

Glutathione peroxidase 1 (Gpx1) is an endogenous antioxidant enzyme. The T allele of the Pro198Leu polymorphism in the Gpx1 (rs1050450, 198C > T) gene is associated with reduced enzyme activity. The aim of this study was to evaluate the association between Pro198Leu polymorphism and risk of diabetic peripheral neuropathy (DPN). We examined 1244 T2DM patients and 730 healthy controls. In the patient group, 33 % had diabetic peripheral neuropathy. All subjects were genotyped for the Gpx1 Pro198Leu polymorphism by polymerase chain reaction and restriction analysis. A significant increase in the T allele and TT genotype frequencies was observed in DPN patients compared to those without DPN (OR 1.55, 95 % CI 1.30-1.85 and 1.89, 95 % CI 1.30-2.74, respectively). The association remained significant after correction for age, disease duration, HbA1c and BMI. When distribution of T allele was compared between DPN+ and DPN- subgroups and controls, OR was 1.54 for DPN+ and 1.00 for DPN- patients. In conclusion, our findings suggest that Gpx1 Pro198Leu genotypes are significantly associated with the risk of diabetic peripheral neuropathy in patients with T2DM. The study provides new clinically relevant information regarding genetic determinants of susceptibility to diabetic neuropathy.

Receptor for advanced glycation end products (RAGE) gene polymorphism and cardiovascular disease in end-stage renal disease patients.

BACKGROUND/OBJECTIVES: Receptor for advanced glycation end products (RAGE) contributes to the pathogenesis of vascular and inflammatory diseases. We investigated whether the functional polymorphism in the promoter region of the RAGE gene (-374 T/A) influences development of cardiovascular disease in the end-stage renal disease (ESRD) patients. METHODS: The cohorts of 1866 ESRD patients and 1143 healthy subjects were genotyped by polymerase chain reaction (PCR) for the RAGE variant rs1800624. RESULTS: The genotype and allele frequencies did not differ significantly between ESRD patients and controls. There was no significant difference in the genotype distribution when patients with CVD were compared to those without it (p for A allele = 0.62). After stratifying CVD patients according to CVD clinical phenotype, the ESRD patients with stroke had a lower frequency of A allele than patients without CVD (0.12 vs. 0.21, p = 0.027). To confirm this finding, we genotyped 163 patients with ischemic stroke but without renal disease. In this group, the AA/TA genotypes were also significantly associated with lower risk of stroke (OR 0.46, p = 0.0002). CONCLUSION: Our data suggest that the presence of the A allele of -374 T/A polymorphism in the RAGE gene has a protective effect against stroke.

Matrix Metalloproteinase-9 (MMP-9) Gene Polymorphism in Stroke Patients.

Matrix metalloproteinases (MMPs), endopeptidases degrading extracellular matrix, play an important role in the pathogenesis of atherosclerosis and vascular disease. The aim of this study was to evaluate the association between the C(-1562)T functional polymorphism in the MMP-9 gene and risk of stroke. We examined 322 patients with stroke and 410 controls. In the patient group, 52 % had type 2 diabetes. All subjects were genotyped for the C(-1562)T polymorphism by polymerase chain reaction and restriction analysis. A significant increase in T allele and CT + TT genotype frequencies was observed in patients compared with controls (OR 1.73, 95 % CI 1.34-2.23 and 1.89, 95 % CI 1.39-2.56, respectively). The T allele carriers were younger at the onset of stroke (63.5 ± 11.7 years) than patients with CC genotype (71 ± 14.1 years) (p = 0.0002). The comparison between patients with T2DM and without it showed that the T allele and CT + TT genotype were more frequent in T2DM patients (OR 1.48, 95 % CI 1.03-2.12 for T allele and 1.44, 95 % CI 1.93-2.24 for CT + TT genotype). In conclusion, our findings suggest that MMP-9 C(-1562)T polymorphism is significantly associated with risk of stroke in patients with and without T2DM.

Matrix metalloproteinase-2 (MMP-2) gene polymorphism and cardiovascular comorbidity in type 2 diabetes patients.

OBJECTIVE: Matrix metalloproteinases (MMPs) play an important role in pathogenesis of atherosclerosis and vascular disease. We hypothesized that MMP-2 might be a susceptibility gene for cardiovascular disease (CVD) in diabetes. The aim of this study was to evaluate the association between C(-1306)T functional polymorphism in the MMP-2 gene and risk of CVD in type 2 diabetes patients. METHODS: We examined 1090 patients with T2DM and 612 controls. All subjects were genotyped for the C(-1306)T polymorphism by polymerase chain reaction (PCR) and restriction analysis. RESULTS: A significant decrease of T allele frequency was observed in patients with CVD versus those with no CVD (OR 0.44, 95% CI 0.36-0.52, p<0.0001). In contrast, OR for CC genotype was 2.19 (1.79-2.68, p<0.0001), conferring 2-fold greater odds for CVD. When the distribution of C(-1306)T was compared in subgroups with different clinical phenotypes of CVD, patients with stroke had the lowest frequency of T allele (6% vs. 11%), compared to entire CVD+ group (p<0.05). CONCLUSIONS: T2DM patients carrying the T allele of MMP-2 C(-1306)T polymorphism have a significantly reduced risk of CVD. The C(-1306)T polymorphism is associated with susceptibility to stroke in T2DM patients.

Polymorphisms of tumor necrosis factor and myeloperoxidase genes in patients with chronic renal failure on peritoneal dialysis.

BACKGROUND: Analyzing the molecular variants of immunological system genes helps to develop our understanding of the pathogenesis of several diseases. The tumor necrosis factor (TNF) is an important cytokine of cellular response and inflammation. The TNF gene is located within the MHC region on chromosome 6p21.3. Single nucleotide polymorphisms in the TNF gene, such as the one at a position -308, probably have a direct influence on TNF production. Myeloperoxidase, a heme enzyme, participates in micro-organism killing. The myeloperoxidase (MPO) gene is located on chromosome 17. In the promoter region, at position -463, G to A transition has been found, which causes decreased gene expression. AIM: The aim of our study was to analyze the genetic polymorphisms of the TNF and MPO genes in patients with chronic renal failure. METHODS: The study included 95 patients with chronic renal failure and 115 healthy individuals. All participants were genotyped for TNF-308 and MPO promoter region polymorphisms by PCR, followed by digestion and gel electrophoresis. Genotype distribution was compared between patients and controls. For statistical analysis the Statistica PL 6.0 program was used. The Kruskal-Wallis and median test were employed; to evaluate relationship between quantitative data chi-square test was used. RESULTS: There were no significant differences in genotype distribution of TNF or MPO polymorphisms between patients and controls. Some differences may be associated with gender because the TNF1/TNF1 genotype was significantly more common in healthy women in comparison with women with chronic renal failure (p < 0.05). In men, no such differences were found. For MPO polymorphism, in men with renal failure the GG genotype was significantly more frequent than in healthy men (p < 0.05). Comparing the MPO genotype distribution in diabetic nephropathy patients and nondiabetic patients, we found a statistically significant difference: GG and AA genotypes were more frequent in diabetic nephropathy than in other renal diseases (73 versus 60% and 10.8 versus 1.7%, respectively; p < 0.05). The genotype distribution in patients with other renal diseases was similar to the control group. There was a correlation between the TNF genotype and the age of onset of glomerulonephritis. For myeloperoxidase, there was a significant association between genotype and the age of onset of renal disease. There was no relationship between the TNF and MPO genotypes and time to end-stage renal disease. CONCLUSION: Our studies show that the TNF and MPO genes may play a role in chronic renal failure. The relationship observed between polymorphisms of the TNF and MPO genes and chronic renal failure may depend on the pathophysiological changes in different diseases underlying renal failure.

Association of the human bradykinin B2 receptor gene with chronic renal failure.

INTRODUCTION: The kallikrein-kinin system plays an important role in blood pressure homeostasis and renal sodium regulation, and some studies have reported that the kinins have a protective effect against hypertension and the development of renal disease. The B2-bradykinin receptor (B2R) mediates the majority of physiological actions of bradykinin. We investigated the effect of the C181-->T polymorphism in exon 2 of the B2R gene in patients with end-stage renal disease (ESRD). METHODS: This study involved 790 patients with ESRD and 510 healthy controls. All participants were genotyped for the B2R C181-->T polymorphism by PCR followed by digestion of a PCR product with TaqI restriction endonuclease. DNA fragments were separated by agarose gel electrophoresis. Genotype and allele frequencies were compared between the groups. All calculations were performed using SPSS 5.0 for Windows. RESULTS: B2R genotype distribution in patients and controls was in accordance with Hardy-Weinberg equilibrium. The frequency of the T allele was higher in ESRD patients than in controls. The significant difference was observed in the age at onset of renal disease; for patients with the T allele the mean age at onset was 36.8 years, compared with 52.4 years for those carrying only the C allele (p<0.001). The frequencies of the T allele and carrier genotypes were not associated with gender, presence of hypertension, or underlying kidney disease. CONCLUSION: Our results suggest that the B2R polymorphism has a potential role in the earlier development of chronic renal failure in susceptible individuals. We did not confirm the previously published reports that the B2R gene polymorphism has a protective role in the development of ESRD.

The intercellular adhesion molecule-1 (ICAM-1) gene polymorphism K469E in end-stage renal disease patients with cardiovascular disease.

The intercellular adhesion molecule-1 (ICAM-1) mediates interaction of activated endothelial cells with leukocytes. It plays an important role in the pathogenesis of atherosclerosis. A functionally important polymorphism of the ICAM-1 gene, K469E, has been described. We investigated whether this polymorphism influences the risk of CVD in end-stage renal disease (ESRD) patients. The groups of 1016 ESRD patients and 824 healthy individuals were genotyped by PCR and allele specific oligonucleotide technique. The T allele of the K469E polymorphism was significantly more frequent in ESRD CVD+ patients than CVD- and controls (OR 2.26, 95% CI 1.87-2.72 and 1.82, 95% CI 1.55-2.11, respectively). The TT genotype was also more frequent in CVD+ patients (OR 9.90, 95% CI 6.17-15.88 vs. CVD- subgroup). When patients were stratified according to clinical outcome of CVD, there was a tendency towards higher frequencies of the T allele and TT genotype in patients with myocardial infarction (OR for T allele 1, 57, 95% CI 1.12-2.18 vs. patients without MI). In the multivariate regression analysis the carrier status of T allele of K469E was an independent risk factor of susceptibility to CVD. Our data suggest that the ICAM-1 K469E polymorphism is associated with CVD in ESRD patients.

Renalase gene polymorphisms in patients with type 2 diabetes, hypertension and stroke.

Renalase is a novel, recently identified, flavin adenine dinucleotide-dependent amine oxidase. It is secreted by the kidney and metabolizes circulating catecholamines. Renalase has significant hemodynamic effects, therefore it is likely to participate in the regulation of cardiovascular function.The aim of our study was to investigate the involvement of renalase gene polymorphisms in hypertension in type 2 diabetes patients. A total of 892 patients and 400 controls were genotyped with three SNPs in the renalase gene. The C allele of rs2296545 SNP was associated with hypertension (P < 0.01). For rs2576178 SNP, frequencies in hypertensive patients differed from controls, but not from normotensive patients. For rs10887800 SNP, the differences in the G allele frequencies were observed in hypertensive patients with stroke, with 66% of patients being GG homozygotes. To confirm observed association we later genotyped 130 stroke patients without diabetes. The OR for risk allele was 1.79 (95% CI 1.33-2.41). In conclusion, the renalase gene polymorphism was associated with hypertension in type 2 diabetes patients. The most interesting result is a strong association of the rs10887800 polymorphism with stroke in patients with and without diabetes. The G allele of this polymorphism might thus be useful in identifying diabetes patients at increased risk of stroke.

Monocyte chemoattractant protein (MCP-1) A-2518G gene polymorphism in stroke patients with different comorbidities.

OBJECTIVES: The aim of our study was to assess the effect of A-2518G polymorphism in the monocyte chemoattractant protein-1 gene on development of stroke. DESIGN AND METHODS: A total of 194 patients with stroke and 320 healthy controls were genotyped for the MCP-1 gene -2518 polymorphism. RESULTS: There was a significant difference in genotype frequencies between ischemic stroke patients and controls (p=0.01). Stroke patients were subdivided according to gender, presence of renal disease, small-vessel disease, diabetes, atherosclerosis and hyperlipidemia. There were differences in genotype frequencies between stroke patients with atherosclerosis and controls (p=0.03), and in allele frequencies between diabetic patients and controls (p=0.04). In hyperlipidemia, the OR 2.33 for the GG genotype may be due to stroke, because it was found only vs. controls and not vs. group without hyperlipidemia. CONCLUSIONS: Our results demonstrate an association between the polymorphism in the regulatory region of MCP-1 gene and susceptibility to ischemic stroke.

Tumor necrosis factor-alpha gene polymorphism correlates with cardiovascular disease in patients with end-stage renal disease.

BACKGROUND AND OBJECTIVE: Tumor necrosis factor-alpha (TNFalpha) is a potent proinflammatory cytokine. Through its effects on lipid metabolism and endothelial function, TNFalpha is involved in cardiovascular disease (CVD). We have studied two polymorphisms in the promoter region of the TNFalpha gene (TNF -308G/A and TNF -238G/A) in end-stage renal disease (ESRD) patients with and without CVD. The aim was to assess the association of these polymorphisms with ESRD and cardiovascular comorbidity in hemodialyzed patients. METHODS: A total of 603 patients with ESRD treated with hemodialysis (382 patients with CVD) and 325 healthy control subjects were genotyped for the TNF -308G/A and TNF -238G/A ploymorphisms by the polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) procedure. RESULTS: The A allele of the TNF -308 polymorphism was more frequent in the ESRD group than in control individuals. The odds ratio (OR) for the risk allele was 2.05 (95% CI 1.48, 2.84). In the subgroup of ESRD patients with CVD, the OR was 5.76 (95% CI 3.67, 9.03) relative to ESRD patients without CVD. There was no association observed between the TNF -238 polymorphism and renal failure or CVD in ESRD patients. CONCLUSION: Our results demonstrate for the first time that the A allele of the TNF -308 polymorphism is associated with CVD in hemodialyzed ESRD patients. If confirmed in prospective studies, it may be a predictor of increased susceptibility to CVD in these patients.

Norepinephrine transporter gene (NET) polymorphism in patients with type 2 diabetes.

BACKGROUND: Norepinephrine transporter (NET) is involved in the regulation of norepinephrine (NE) turnover and metabolism. Neuronal NE reuptake may be impaired in individuals with renal disease and/or hypertension due to dysfunction of the NE transporter. A silent G1287A nucleotide substitution in exon 9 of the NET gene was studied in human conditions involving hypertension. We investigated its effect in patients with type 2 diabetes. METHODS: The study involved 215 type 2 diabetes patients with nephropathy, 95 patients with diabetes duration > or =10 years, free of nephropathy, and 360 healthy subjects. All individuals were genotyped for the NET-8 gene polymorphism with the PCR-RFLP method. Genotype and allele frequencies were compared between the groups. NE was measured by high-performance liquid chromatography and electrochemical detection. RESULTS: We genotyped 310 patients and 360 controls for the NET gene polymorphism. Genotype distribution in both groups was in accordance with the Hardy-Weinberg equilibrium. There were no significant differences in the frequency of genotypes and alleles between patients and controls (p = 0.43). The frequencies were also similar for patients with nephropathy and those without. After dividing the patient group into hypertensive (n = 208) and normotensive (n = 102) subjects, there was a significant increase in the frequency of the AA genotype in patients with hypertension compared to normotensives (19 vs. 10%, p < 0.05). CONCLUSION: No association was found between G1287A polymorphism in the NET gene and diabetes. Our results suggest that this polymorphism has a possible role in increased susceptibility to hypertension in patients with type 2 diabetes.

Genetic determination of TNF and myeloperoxidase production in dialyzed patients with diabetic nephropathy.

INTRODUCTION: Diabetic nephropathy accounts for more than 20% of the cases of chronic renal failure. For many patients, the method of renal replacement therapy is chronic ambulatory peritoneal dialysis (CAPD). Diabetes, through glucose autooxidation and production of free radicals, causes protein glycation. Products of protein glycation increase the concentrations of proinflammatory cytokines. The tumor necrosis factor (TNF) is one of the most important cytokines of cellular response and inflammation. Its level is increased in chronic renal failure. Numerous polymorphisms have been identified within and around the TNF gene, which is located on chromosome 6. Single nucleotide polymorphisms, such as a polymorphism at a position -308, probably have a direct influence on the TNF production. Myeloperoxidase (MPD) is a heme enzyme, participating in oxygen mechanisms of microorganism killing by phagocytes. Chronic renal failure patients show a significant reduction in the intracellular myeloperoxidase level. In the promoter region of myeloperoxidase gene, at position -463, G to A transition has been found, which causes a decreased gene expression. The aim of the present study was an analysis of genetic basis of TNF and myeloperoxidase production in dialyzed patients with diabetic nephropathy. SUBJECTS AND METHODS: The study group consisted of 37 diabetic nephropathy patients treated with peritoneal dialysis. The control subjects were 58 dialyzed patients with other primary renal diseases and 115 healthy individuals. TNF and myeloperoxidase gene polymorphisms were detected by polymerase chain reaction (PCR) and amplification products were digested with the NcoI and AciI restriction enzymes respectively. ELISA determined the TNF and MPO levels in plasma. RESULTS: We haven't found significant differences in TNF genotype and allele frequencies between the groups; however, diabetic nephropathy patients seemed to have a lower frequency of TNF1/TNF1 genotype. In diabetic nephropathy patients, the median TNF plasma level was 43.8 pg/mL, and in other renal diseases it was 36.8 pg/ mL. The difference was significant (p<0.05). The differences in TNF levels between both groups and the control group (1.7 pg/mL) were highly significant (p<0.001). There was a statistically significant difference in MPO genotype frequencies between patients with diabetic nephropathy and patients with other renal diseases (p<0.05). GG and AA genotypes were significantly more common in patients with diabetic nephropathy. The genotype distribution in patients with other renal diseases was similar to the distribution in the control group. Median plasma MPO level in diabetic nephropathy patients was similar to patients with other renal diseases. A significantly lower level (p<0.05) was observed in the control group. In diabetic nephropathy, we have also observed a correlation between the MPO genotype and an earlier onset of the disease. For the TNF genotype, we haven't found such a relationship. There was also no relationship between the TNF and MPO genotypes and time to end-stage renal disease (ESRD). There were no differences in the frequency of peritonitis between patients with diabetic nephropathy and dialyzed patients with other renal diseases. DISCUSSION: In conclusion, we found that in diabetic nephropathy patients molecular variants of TNF are more frequent than in nondiabetic patients with chronic renal failure and these changes might be associated with altered ability to TNF synthesis. Analysis of the myeloperoxidase genotypes showed significant difference in genotype distribution in dialyzed patients with diabetic nephropathy. This, however, requires further studies to confirm the relationship with the disease.

Changes of surface tension of dialysate depending on its composition in continuous ambulatory peritoneal dialysis.

Surface phenomena resulting from interactions among molecules occur commonly in nature. Surfactants, substances with surface activity, have a big influence on surface tension. They reduce surface tension when added to the solution, even in minimal concentration. The behaviour of surface tension of the dialysate is difficult to properly assess, because of its complex composition. Dialysate is a mixture of organic and inorganic substances, both macro- and micromolecular. Among them are proteins, phospholipids, fatty acids. In the literature there are no publications showing the behaviour of surface tension of the dialysate. The aim of the study was the assessment of changes of dialysate surface tension in non-complicated continuous peritoneal dialysis (CAPD), depending on time of the presence of dialysis fluid in the peritoneal cavity and on the concentration of different substances in it. The study was performed on 39 dialysate samples obtained from 6 patients chronically treated with continuous ambulatory peritoneal dialysis (CAPD). During the study patients had no symptoms of peritonitis. Surface tension of the dialysate was determined, using the Wilhelmy's method. Ten measurements were performed in every sample of the dialysate and the mean values and standard deviation were calculated. Simultaneously the concentrations of sodium, glucose, urea, creatinine, total protein were measured in the dialysate. As a result of the study a significant negative correlation between dialysate protein concentration and surface tension was found. The significant negative correlation between surface tension and the dwell time was also found. There was no significant correlation between the value of surface tension of the dialysate and concentrations of glucose, urea, creatinine and sodium.