Impact of glycemic control on survival of diabetic patients on chronic regular hemodialysis: a 7-year observational study.
Explore the source record for details and available documents.
Biomedical subjects
Publications and source records attributed to Ewa Zukowska-Szczechowska.
Explore the source record for details and available documents.
Explore the source record for details and available documents.
BACKGROUND: Excessive flux through the polyol pathway has long been thought to be involved in the pathogenesis of diabetic microvascular complications. Aldose reductase (AR) is the first and rate-limiting enzyme in the pathway that catalyses the reduction of glucose to sorbitol. A frequent C-106T polymorphism in the promoter of the AR gene has been described, which may change the expression of the gene. The aim of the study was to examine if the C-106T polymorphism was associated with diabetic nephropathy. MATERIAL AND METHODS: We collected 444 patients with type 2 diabetes and divided them into three groups according to the renal status: 162 patients with normoalbuminuria, 153 with microalbuminuria and 129 with persistent proteinuria. Each subject was genotyped for the C-106 polymorphism using the PCR-based RFLP protocol. RESULTS: When the whole study population was analysed, no distortion in the genotype frequency among the study groups was observed. When we stratified the study population by HbA1c we found that in patients with HbA1c > or =9% (median) the CT and TT genotypes were more frequent in patients with diabetic nephropathy (proteinuria and microalbuminuria) than those with normoalbuminuria (OR 2.04, 95% CI 1.12-3.74). CONCLUSION: The C-106T polymorphism in the AR gene is a risk factor for development of diabetic nephropathy in type 2 diabetes in patients with poor glycaemic control.
UNLABELLED: BACKGROUND/AIMS;Higher blood pressure (BP) in winter has been documented in healthy and hypertensive adults. It may potentially contribute to the observed excess winter cardiovascular mortality in the general population. The aim of the study was to assess whether BP varies similarly among patients with chronic renal failure on haemodialysis treatment, who present an increased risk of cardiovascular death. METHODS: We retrospectively analysed values of pre-dialysis BP and parameters of fluid retention--pre-dialysis body weight and inter-dialytic weight gain measured in 49 patients (23 male, 26 female; aged 46.0+/-13.5 years) from 1995 to 1998. For each patient we calculated deviations of monthly mean values of systolic BP, diastolic BP, pre-dialysis body weight and inter-dialytic weight gain from the lowest monthly means of these parameters in a given year. Monthly means of these deviations for the whole study group (dSBP, dDBP, dBW, dWG, respectively) were subsequently computed. Monthly means of air temperature (T), air relative humidity (H) and atmospheric pressure (AP) were provided by the local Institute of Meteorology. The Wilcoxon paired test was applied to compare mean values of BPs and parameters of fluid retention of every patient in three warmest and three coldest months of each year. Spearman rank correlation analysis was employed to evaluate relationships between dSBP, dDBP and climatic variables, dBW or dWG. RESULTS: Systolic BP was higher in summer than in winter (146.6+/-20.5 vs 143.4+/-18.9 mmHg; p<0.00001). Diastolic BP was also higher in summer than in winter (82.6+/-8.5 vs 79.6+/-7.3 mmHg; p<10(-9)). Pre-dialysis body weight and inter-dialytic weight gain did not differ between summer and winter (66.0+/-13.2 vs 66.0+/-13.2 kg; p=0.98 and 2.27+/-0.6 vs 2.29+/-0.5 kg; p=0.53). There was a positive correlation between dSBP and T (RS=0.424, p<0.003), as well as dDBP and T (RS=0.591, p<0.00001) and an inverse correlation between dSBP and H (RS=-0.372, p<0.01), as well as dDBP and H (RS=-0.408, p<0.004). There were no significant associations between BPs and AP, dBW or dWG. CONCLUSIONS: In haemodialysed patients from southern Poland, BP is higher in summer than in winter. Changes in BP are related to seasonal changes in climatic variables--air temperature and air relative humidity. Seasonal variation in BP is not associated with variation in fluid retention. Possible alteration of cardiovascular reactivity to changes in climatic environment in haemodialysed chronic renal failure patients may be one of the potential explanations of these observations.
Explore the source record for details and available documents.
Explore the source record for details and available documents.
Beta2-adrenergic receptor gene and neuropeptide Y gene may potentially influence lipid metabolism and overall energy balance. Therefore, we examined associations of these genes with lipid fractions and obesity-related phenotypes in hypertensive subjects. A total of 638 white individuals from 212 Polish families with clustering of essential hypertension were phenotyped for cardiovascular risk determinants. Each subject was genotyped for functional polymorphisms of beta2-adrenergic receptor gene (Arg16Gly and Gln27Glu) and neuropeptide Y (Leu7Pro). Of 3 common haplotypes of beta2-adrenergic receptor gene, Arg16Gln27 was overtransmitted to offspring with elevated levels of total cholesterol (Z=2.2; P=0.026) and LDL-cholesterol (Z=3.2; P=0.002). Individually, Leu7Pro was not associated with any of the metabolic phenotypes in family-based tests or case-control analyses. However, in the presence of Arg allele of Arg16Gly and Gln allele of Gln27Glu, homozygosity for Leu variant of the Leu7Pro polymorphism was associated with 2.1-increased odds ratio (confidence interval, 1.10 to 3.81; P=0.024) of elevated LDL in hypertensive subjects, independent of age, gender, body mass index, adjusted blood pressures, antihypertensive therapy, and use of nonselective beta-blockers and diuretics. Consistently, there was a significant multilocus association among variants of Arg16Gly, Gln27Glu, and Leu7Pro in hypertensive probands with elevated LDL (cases; P=0.028) but not in hypertensive subjects with normal LDL (controls). This study revealed an association of LDL-cholesterol with beta2-adrenergic receptor gene haplotype and provided evidence for epistatic interaction between beta2-adrenergic receptor gene and neuropeptide Y gene in determination of LDL-cholesterol in patients with essential hypertension.
OBJECTIVE: Males are at higher risk of cardiovascular diseases than females. The aim of the study was to test whether the potential of the Y chromosome to affect cardiovascular risk could be attributed to its influence on lipids. METHODS AND RESULTS: 1288 Polish men (1157 subjects from young healthy cohort and 131 individuals from middle-aged hypertensive population) were phenotyped for determinants of cardiovascular risk including BMI, blood pressures, lipids, and testosterone. Each subject was genotyped for the HindIII(+/-) polymorphism within the nonrecombining region of the Y chromosome. Men with the HindIII(-) variant exhibited significantly higher total cholesterol (TC) and low-density lipoprotein cholesterol (LDL) levels than subjects with the HindIII(+) genotype in both populations. The differences between the genotypes were 0.15 mmol/L (P=0.0107) and 0.45 mmol/L (P=0.0377) in TC and 0.15 mmol/L (P=0.0059) and 0.41 mmol/L (P=0.0432) in LDL among young apparently healthy men and middle-aged hypertensive men, respectively. The HindIII(+) was associated with a significant increase in blood pressure of the middle-aged men. Testosterone serum concentrations correlated positively with HDL-cholesterol levels, and this association was independent of the Y chromosome. CONCLUSIONS: The results indicate that a locus/loci on the Y chromosome may influence LDL levels, independent of testosterone levels.
OBJECTIVE: This study was undertaken to evaluate to what extent C-reactive protein (CRP) can be reduced by exercise by examining its circulating concentrations in male ultramarathon runners and to determine if low leptin as a robust circulating marker of fat mass could account for low CRP in such men. METHODS AND RESULTS: Sixty-seven male ultramarathon runners and 63 sedentary male controls of similar age and body mass index were recruited. CRP and leptin were measured by ELISA and radioimmunoassay, respectively. Median CRP concentration in lean (body mass index <25 kg/m2) marathon runners was less than half control median (0.4 [0.2 to 0.9] mg/L versus 0.9 [0.5 to 2.7] mg/L, P=0.0013) and, more strikingly, in nonlean runners was approximately 26% of control median (0.4 [0.3 to 0.8] mg/L versus 1.5 [0.9 to 2.5] mg/L, P=0.0002). Circulating leptin levels were also substantially lower in lean (45% less) and nonlean (63% less, both P<0.0001) ultramarathon runners. However, interleukin-6 levels were not different. Furthermore, leptin adjustment only minimally attenuated the case-control difference in CRP, suggesting that mechanisms other than fat mass reduction contribute to low concentrations of CRP in marathon runners. CONCLUSIONS: This study suggests that circulating CRP concentrations can be markedly suppressed, independently of total adiposity or indeed fat mass, by intense regular physical exercise.
BACKGROUND: Methylenetetrahydrofolate reductase (MTHFR) is a regulatory enzyme of homocysteine metabolism. The C677T polymorphism of the MTHFR gene has been reported to be associated with elevated plasma homocysteine in patients with low folic acid intake. A recently reported second common polymorphism, A1298C, may increase homocysteine, but only in individuals carrying the T677 allele. This study aimed to investigate the influence of the C677T and A1298C polymorphisms of the MTHFR gene on the development of diabetic nephropathy in Caucasian patients with type 2 diabetes. METHODS: We genotyped 429 type 2 diabetic patients for the C677T and A1298C polymorphisms using standard PCR-based protocols, and divided them into three groups based on renal status: 159 patients with normoalbuminuria, 149 with microalbuminuria, and 121 with persistent proteinuria and chronic renal failure (CRF). The C677T and A1298C genotype frequencies were compared among the three groups. RESULTS: Although the frequencies of the CT and TT genotypes of the C677T polymorphism tended to increase with each stage of diabetic nephropathy (53, 56 and 63% in normoalbuminuria, microalbuminuria and proteinuria/CRF, respectively), these differences were not significant. When male and female patients were analysed separately, the effect was seen only in males. The CT + TT genotype was present in 46% of male patients with normoalbuminuria, in 57% with microalbuminuria and in 68% with proteinuria/CRF (OR = 2.46; 95% CI 1.13-5.38). There were no differ-ences in the A1298C polymorphism among the three groups. CONCLUSIONS: These findings indicate that the C677T polymorphism is a risk factor for diabetic nephrop-athy in male patients with type 2 diabetes.
Explore the source record for details and available documents.
This paper presents the role of erythropoietin application in diabetic patients with accompanying renal failure. The main cause of anemia in diabetics are: nephropathy, structural lesions of erythrocyte membrane and blood loss connected with diagnostic and therapeutic actions. There are publications which demonstrate that in patients with diabetes type 1 or 2 with accompanying nephropathy, anemia appears more frequently than in the group of patients with chronic renal failure caused by other factors. It is supposed, that the impaired erythropoietin synthesis in diabetics can be caused by autonomic neuropathy. Erythropoietin administration in case of diabetic nephropathy has a beneficial influence on fat metabolism, immune response and reduction of insuline resistance. Erythropoietin because of reduction of vascular endothelial growth factor synthesis blocks the development of diabetic retinopathy and macroangiopathy. Erythropoietin reduces the risk of the left-ventricular hypertrophy caused by anemia. Very important is that the erythropoietin resistance is lower in diabetics. Scientists who are adverse to erythropoietin administration in patients with diabetic nephropathy maintain, that it can lead to vascular complications and the deterioration of glycemia control.
The results of many studies performed on animals and humans strongly suggest that genetic factors lead to the development of hypertension (HT). Syndromes in which mutations in single genes are sufficient to result in large changes of blood pressure are rare. Nevertheless, it is anticipated that their understanding will lead to new insights into forms of hypertension occurring more often, including essential hypertension. At least 9 monogenic forms of HT including Liddle syndrome, type I familial hyperaldosteronism (GRA) and type II familial hyperladosteronism, Gordon syndrome, apparent mineralocorticoid excess syndrome (AME), hypertension associated with type E brachydactyly, glucocorticoid receptor mutations, type IV congenital adrenal hyperplasia (CAH) (11 beta-hydroxylase deficiency), and type V CAH (17 alpha-hydroxylase deficiency) have been described so far.
Advanced glycosylation end products (AGEs) are involved in the patho-genesis of diabetes mellitus, end stage renal failure, hypertension and its complications. The influence of AGEs on hypertension is exerted by oxidative stress, vascular remodelling, impaired nitric oxide metabolism, and immunological disturbances. The investigations aiming to explain the reasons of disturbed metabolism of AGEs in hypertension will implicate therapeutic interventions.
BACKGROUND: It has been recently suggested that the presence of the methylenetetrahydrofolate reductase gene 677TT genotype is associated with younger age at initiation of dialysis, thus raising a hypothesis that younger renal patients carrying the TT genotype are at higher risk to develop end-stage renal disease. The aim of this study was to test the association between the C677T polymorphism and the presence of end-stage renal disease using a family-based study design. MATERIAL AND METHOD: C677T polymorphism was genotyped in a group of 247 family trios (offspring affected with end-stage renal disease, dialysed or conservatively treated, and both parents). Transmission/disequilibrium test (TDT) was used to evaluate allele transmission from heterozygous parents to affected offspring. RESULTS: The TDT analysis revealed no significant deviation in the transmission of the MTHFR C677T alleles to CRF patients (51 vs. 49% for the C allele and T allele transmission, respectively). We observed a significant relationship between MTHFR genotypes and total plasma homocysteine (tHcy), as well as folate concentration. Also, plasma tHcy and folate were negatively correlated. CONCLUSION: Our results did not show any association between the MTHFR reductase C677T polymorphism and the increased risk of the development of end-stage renal disease. Whether this polymorphism contributes to the faster rate of decline of renal function in renal patients, must be evaluated further.
A region on human chromosome 5 (5q31.1-qter) contains several genes that encode important blood pressure regulators and thus is a good candidate for analysis of linkage and association with hypertension. We recruited 638 individuals from 212 Polish pedigrees with clustering of essential hypertension. These subjects were genotyped for 11 microsatellite markers that span this region to test for linkage to essential hypertension and systolic and diastolic blood pressures. The segment of this region of approximately 7 cM delineated by D5S1480 and D5S500 markers was linked to blood pressures in multipoint analysis. In 2-point analysis, D5S1480--the marker in close proximity to beta2-adrenergic receptor gene--reached the maximal linkage to essential hypertension and adjusted systolic and diastolic blood pressures, implicating this gene as a positional candidate for further association studies. Arg16Gly, Gln27Glu, and Thr164Ile--3 functional single nucleotide polymorphisms within the beta2-adrenergic receptor gene--were tested for association with essential hypertension. None of these polymorphisms showed a significant association with essential hypertension, separately or in the haplotype analysis. This study provided evidence of linkage of 5q31.1-5qter region to essential hypertension in the European population. Moreover, it implicated the chromosomal segment in close proximity to D5S1480 and D5S500. The detailed analysis of 3 single nucleotide polymorphisms does not support the role of the beta2-adrenergic receptor gene as a major causative gene for the detected linkage.
Higher blood pressure (BP) in males compared with females is well documented and is thought to be influenced in part by the Y chromosome. To examine whether there is an association between BP and a polymorphic HindIII biallelic marker in the nonrecombining region of the Y chromosome, we genotyped 155 males from a Polish study group and 762 males from a Scottish study group. We also tested for possible interaction between the Y chromosome and a mutation in the steroidogenic factor binding site of the aldosterone synthase gene by genotyping the same group from Scotland. There was no significant difference in age or body mass index between 2 Y chromosome genotypes in both study groups. Men with the HindIII(+) genotype had significantly higher systolic and diastolic pressures than those with the HindIII(-) genotype in both the Polish and Scottish studies. This difference between the genotypes was 5.27 mm Hg (P=0.0014) and 3.14 mm Hg (P=0.0005) for adjusted systolic BP and 2.6 mm Hg (P=0.0045) and 1.44 mm Hg (P=0.0084) for adjusted diastolic BP in the Polish and the Scottish studied, respectively. On binary logistic regression analysis, males with the HindIII(+)/TT SF1 genotype combination had an odds ratio for elevated BP of 3.92 (CI 1.21 to 12.68, P=0.023). Our results indicate that the Y chromosome harbors a locus or loci that contribute to BP variation in hypertensive and normotensive men. The polymorphism in the aldosterone synthase gene may interact with the Y chromosome to increase the odds of an individual's developing higher BP.
Apoptosis (genetically programmed cell death) plays a key role in human physiology and pathogenesis of various diseases, including cancer. A suicide of cell can be initiated by many different factors, but activation of caspases, which are a special class of proteolytic enzymes, is always involved in this process. Activation of caspases may be achieved by several molecular pathways: the best known stimuli triggering caspase cascade are stimulation of Fas or TNF receptors, release of cytochrome c from the cellular mitochondria and exposure to granzymes, which are secreted by cytotoxic T cells. Activated caspases digest many cellular proteins responsible for cell cycle regulation (e.g. RB, MDM2), DNA damage recognition and repair (e.g. DNA-PK, P53, PARP), and regulation of the cellular structure (e.g. actin and lamins). All these functional and structural protein modifications lead directly to apoptosis. Further research on the mechanisms controlling caspase activity and the modes of action will provide better insight into pathogenesis of cancer and other disorders. It may be even the first step to design new and more efficient methods of conventional tumor treatment or gene therapy.