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J Chudek

Publications and source records attributed to J Chudek.

At least 37 records · Page 2Linked to original sources
PubMed1998

Does the vitamin D receptor genotype predict bone mineral loss in haemodialysed patients?

BACKGROUND: It has been suggested that the vitamin D receptor (VDR) gene BsmI-polymorphism is a genetic determinant of bone metabolism. DESIGN: To test this hypothesis, the relationship between VDR genotypes, bone mineral density (baseline and after 18 months) and parameters of calcium metabolism and bone turnover were investigated prospectively in 88 haemodialysed patients not receiving active vitamin D metabolites. METHODS: Whole body, lumbar spine and femoral neck bone mineral density (BMD) were assessed by dual energy X-ray absorptiometry (DEXA). In addition calcium, phosphorus, 25(OH)D3, 1,25(OH)2D3, osteocalcin serum concentrations, alkaline phosphatase activity and intact 1,84 PTH levels were measured. RESULTS: VDR genotype BB, Bb and bb were found in 27, 49 and 24% of patients. Initial BMD (g/cm2) of whole body, lumbar spine and femoral neck did not differ between genotypes (whole body: BB 1.055 +/- 0.120, Bb 1.082 +/- 0.102, bb 1.128 +/- 0.120; lumbar spine: BB 1.075 +/- 0.199, Bb 1.079 +/- 0.185, bb 1.099 +/- 0.170; femoral neck: BB 0.808 +/- 0.160, Bb 0.862 +/- 0.127, bb 0.842 +/- 0.125; mean +/- SD), but the decrease of whole body and femoral neck BMD during 18 months was significantly (P < 0.02) different between the genotype groups (whole body: BB -0.048 +/- 0.028, Bb -0.031 +/- 0.029, bb -0.024 +/- 0.023; femoral neck BB -0.044 +/- 0.069, Bb -0.032 +/- 0.081, bb -0.012 +/- 0.029 g/cm2). CONCLUSION: This preliminary study suggests faster mineral loss in BB genotype of VDR in haemodialysed patients.

Adolescent↗
PubMed1998

The genetics of renal tumors in end-stage renal failure differs from those occurring in the general population.

The genetics of renal cell tumors (RCT), which occur at a high frequency in patients with end-stage renal failure (ESRF), is not yet known. Using a fluorescence microsatellite assay and comparative genomic hybridization, 18 renal tumors obtained from nine patients with ESRF were analyzed for genetic alterations, which are known to be characteristic of common nonpapillary and papillary RCT in the general population. Deletion of chromosome 3p was detected in six nonpapillary tumors, whereas trisomies of 7 and 17 or 3, 8, and 16 were seen in four of 18 tumors. No alterations were found in four tumors, and another four tumors had unspecific changes. The fragile histidine triad (FHIT) gene is localized at the most common fragile site at chromosome 3p14.2. The FHIT and the p53 tumor suppressor gene are targets of different environmental agents. Because both toxic effect and genomic instability are implicated in the development of renal cysts in ESRF, the alteration of both genes in tumor cells was analyzed. No abnormal expression of the FHIT gene or mutation of the p53 gene were found. This study suggests that the genetics and also the morphology of some of the ESRF RCT differ from those known for RCT in the general population.

Acid Anhydride Hydrolases↗
PubMed1998

[Vitamin D receptor gene polymorphism and the rate of bone loss of the femur neck and lumbar spine in hemodialized patients with chronic renal failure].

It has been suggested that the vitamin D receptor (VDR) gene Bsml-polymorphism is a genetic determinant of bone metabolism. To test this hypothesis, the relationship between VDR genotypes, bone mineral density (baseline and after 18 months) and parameters of calcium metabolism and bone turnover were investigated prospectively in 136 haemodialyzed patients. Lumbar spine and femoral neck bone mineral density (BMD) were assessed by dual energy X-ray absorptiometry (DEXA). In addition calcium, phosphorus, 25(OH)D3, 1.25(OH)2D3, osteocalcin serum concentrations, bone alkaline phosphatase activity and intact 1, 84-PTH levels were measured. VDR genotype BB, Bb and bb were found in 24%, 46% and 30% of patients respectively. Initial BMD (g/cm2) of lumbar spine and femoral neck did not differ between genotypes, however the decrease of femoral neck BMD during 18 months of observation differ significantly (p < 0.02) between the particular genotype groups (femoral neck: BB -0.031 +/- 0.029; Bb -0.027 +/- 0.017; bb -0.017 +/- 0.019 g/cm2). Significantly lower serum level of 25OHD3 was found in patients with the BB genotype before and after 18 months of observation in comparison to the respective values obtained in bb genotype patients, (respectively, 21.0 +/- 16.8 ng/ml vs 30.8 +/- 17.9 ng/ml; p < 0.01 and 24.0 +/- 10.8 ng/ml vs 32.4 +/- 16.0 ng/ml; p < 0.02). BB genotype patients were also characterised by significantly lower serum level of 1.25(OH)2D3 both initially and after 18 month of the study (respectively in BB and bb patients 25.9 +/- 9.7 pg/ml vs 30.7 +/- 10.0 pg/ml; p < 0.02 and 18.4 +/- 12.3 pg/ml vs 24.3 +/- 13.0 pg/ml; p < 0.01). No significant differences were found in Ca, P, osteocalcin, iPTH serum concentrations and bone fraction of alkaline phosphatase activity between particular genotypes. Results from this study suggest that faster bone mineral loss and more exaggerated disturbances of vitamin D metabolism are present in haemodialyzed uraemic patients with BB than bb genotype of VDR.

Adult↗
PubMed1998

Genetic abnormalities in parathyroid nodules of uremic patients.

The molecular pathway of autonomous growth of the parathyroid glands in uremic patients is poorly understood. We have analyzed 71 parathyroid lesions from 24 patients with refractory hyperparathyroidism for allelic loss at chromosomes 1, 3, 6, 9, 11, 12, 13, 15, and 17 and at the X chromosome. Microsatellite analysis was performed using 24 highly polymorphic markers. Deletions at chromosomes 1, 3, 6, 11, 12, and 13 and at the X chromosome were detected in only 10 of 67 nodules (15%). No allelic loss of the p16 and p53 tumor suppressor genes or the extracellular calcium receptor gene was found. The X-chromosome inactivation assay revealed a monoclonal pattern in 58% of hyperplastic nodules in females. Our results indicate monoclonal growth in the majority of hyperplastic nodules and suggest that some of these lesions might be considered precursors for adenoma development.

Female↗
PubMed1998

[Serum erythropoietin concentration in women with uterine or ovarian tumors].

Patients with uterine or ovarian tumors frequently develop anaemia. Causes of anaemia in these patients are still not fully understood. We assessed serum erythropoietin (EPO) concentration in 70 women with benign or malignant uterine or ovarian tumors and in 43 control women. Thirteen women out of 50 with benign and 7 out of 20 with malignant tumors (26% and 35% respectively) were anaemic. In patients with benign tumors serum EPO concentrations did not differ from that in control subjects. In patients with malignant tumors plasma EPO was inappropriately low with respect to the haemoglobin concentration. From results obtained in this study it seems, that uterine or ovarian malignancy exerts a suppressive effect on EPO secretion. Inappropriately low EPO plasma concentration may account for the anaemia frequently occurring in these women.

Adult↗
PubMed1997

Detailed microsatellite analysis of chromosome 3p region in non-papillary renal cell carcinomas.

Multiple hemi- and homozygous interstitial deletions at chromosome 3p have been found in different types of cancer, including non-papillary renal cell carcinoma (RCC). To determine the frequency and size of deletions, we have analyzed paired normal and tumor DNA obtained from short-term cultures of 104 non-papillary RCCs with 29 microsatellite markers covering the entire chromosome 3p region. Deletion mapping provided evidence for terminal deletion, with the most distal breakpoint between loci D3S1606 and D3S3666 in 94 cases, whereas constitutional heterozygosity was retained at all loci in 4 RCCs. In 6 cases, interstitial deletions were detected. Deletion mapping detected the smallest overlapping region between loci D3S3666 and D3S1560, which corresponds to an approx. 55 cM genetic distance.

Carcinoma, Renal Cell↗
PubMed1997

Loss of heterozygosity at chromosomes 8p, 9p, and 14q is associated with stage and grade of non-papillary renal cell carcinomas.

In this study, 105 non-papillary renal cell carcinomas (RCCs) have been examined for allelic loss at the chromosome 8p12-21.1, 9p21, and 14q24.2-qter regions, each by two highly polymorphic microsatellites. Loss of heterozygosity (LOH) was detected at both chromosome 8p and 9p in 33 per cent of the cases and at chromosome 14q in 45 per cent of the tumours. A correlation of variables such as size, grade, and stage of tumours with these specific genetic alterations showed that loss of chromosomes 8p and 9p, and especially loss of chromosome 14q regions, is significantly associated with a higher grade of tumour and the combined LOH at these chromosomal sites with advanced tumour stage. These genetic alterations did not show any correlation with the size of non-papillary RCCs. This study suggests that genetic markers at the above-mentioned chromosomal sites can predict the clinical outcome of non-papillary RCCs.

Carcinoma, Renal Cell↗
PubMed1997

Influence of water immersion on plasma erythropoietin concentration in patients with essential hypertension.

UNLABELLED: Water immersion (WI) is followed by hypoxemia and hemodilution, and induces alterations in renal hemodynamics (increase in tubular sodium load). These facts justified the performance of studies which aimed to assess the influence of WI on erythropoietin (EPO) secretion. Serum EPO and atrial natriuretic peptide (ANP) concentrations as well as plasma renin activity (PRA) were estimated in 18 patients with essential hypertension (EH) and in 9 healthy subjects (HS): before, after 2 h of WI and 2 h after discontinued WI. WI was followed by a significant increase in plasma volume and decrease in PRA, which were of similar magnitude in both examined groups. Patients with EH showed significantly higher basal levels of serum EPO (66.7+/-11.4 mU/ml in EH vs. 20.0+/-3.4 mU/ml in HS) and ANP (110.6+/-15.4 pg/ml in EH vs. 75.6+/-8.2 pg/ml in HS). WI was followed by a significant increase in both EPO (by 34.0+/-8.9 mU/ml in EH and 17.0+/-5.4 mU/ml in HS) and ANP (by 106.9+/-19.2 pg/ml in EH and 149.4+/-16.9 pg/ml in HS). Only in EH, a significant correlation was found between serum EPO level and mean arterial pressure post WI and natriuresis during WI, respectively. CONCLUSIONS: (1) water immersion induced increase in plasma EPO both in healthy subjects and patients with essential hypertension. (2) Patients with EH are characterized by elevated basal plasma levels of ANP and EPO. (3) Participation of the renin-angiotensin system and ANP in the regulation of EPO secretion could not be proven both in normotensive subjects and hypertensive patients.

Adult↗
PubMed1997

Significance of chromosome arm 14q loss in nonpapillary renal cell carcinomas.

We examined 88 nonpapillary renal cell carcinomas for allelic loss at chromosome arm 14q and correlated the results to size, grade, and stage of these tumors. Fourteen highly polymorphic microsatellite markers on the long arm of chromosome 14 were used for deletion mapping. Loss of heterozygosity (LOH) at the smallest overlapping segment of 14q24.2-qter was seen in 42 of 88 tumors. There was no significant correlation between frequency of 14q LOH and size of tumors (P = 0.11). LOH was frequently seen in grade 2 and 3 tumors (55% and 73%, respectively) and in stage III and IV tumors (53% and 80%, respectively). We found a significant correlation between chromosome arm 14q LOH and nuclear grade (P < 0.001) and stage (P < 0.001) of tumors. These observations indicate the presence of a tumor-suppressor gene at chromosome segment 14q24.2-qter and demonstrate the usefulness of microsatellite analysis for assessing the possible clinical outcome of nonpapillary renal cell carcinomas.

Adult↗
PubMed1997

[Distal tubular acidosis in a patient with insulin dependent diabetes mellitus--selected pathophysiologic, diagnostic and therapeutic aspects].

This case report describes a 42 years old male patients with distal tubular renal acidosis in whom the symptomatology of this disorder was markedly changed by the presence of concomitant endocrine and exocrine insufficiency of the pancreas. Pathophysiological, diagnostic and therapeutic aspects of coexistence of these two type of pathology are stressed.

Acidosis, Renal Tubular↗
PubMed1997

[Adrenomedullin].

Explore the source record for details and available documents.

Adrenomedullin↗
PubMed1996

[The influence of water immersion on serum erythropoietin concentration in patients with essential arterial hypertension].

UNLABELLED: Water immersion (WI) is followed by hypoxemia and haemodilution, and induces alterations in renal haemodynamics (increase of tubular sodium load). These facts justified the performance of studies which aimed to assess the influence of WI on EPO secretion. Serum EPO and atrial natriuretic peptide (ANP) concentration and plasma renin activity (PRA) were estimated in 18 patients with essential hypertension (EH) and in 9 healthy subjects (HS) before, after two hours of WI and two hours after discontinued WI. WI was followed by a significant increase of plasma volume and decrease of PRA which were of similar magnitude in both examined groups. Patients with EH showed significantly higher basal levels of serum EPO (66.7 +/- 11.4 mU/ml in EH vs 20.0 +/- 3.4 mU/ml in HS) and ANP (110.6 +/- 15.4 pg/ml in EH vs 75.6 +/- 8.2 pg/ml in HS). WI was followed by significant increase of both EPO (by 34.0 +/- 8.9 mU/ml in EH and 17.0 +/- 5.4 mU/ml in HS) and ANP (by 106.9 +/- 19.2 pg/ml in EH and 149.4 +/- 16.9 pg/ml in HS). Only in EH a significant correlation was found between serum EPO level and MAP and post-WI natriuresis respectively. CONCLUSIONS: 1. Patients with EH are characterized by elevated basal serum levels of ANP and EPO. 2. Participation of the renin-angiotensin system and ANP in the regulation of EPO secretion could not be proven both in normotensive and hypertensive patients. 3. Involvement of EPO in the pathogenesis of EH seems to be likely.

Adult↗
PubMed1995

[Imidazol receptor agonists--new possibilities for treating hypertension].

Adrenergic alpha 2-receptors mediate important regulatory functions in both the brain and the periphery. Activation of these receptors lowers blood pressure through a decrease in sympathetic and vasomotor nerve activity. Agonists of the alpha 2-adrenoceptors are often used in the treatment of arterial hypertension. As recently discovered, their chemical structure includes so called "imidazoline ring" and compounds with such chemical structure bind to nonadrenergic sites known as imidazoline receptors. These receptors are localized in midportions of the brain but they are also present in other organs such as lungs, heart, adrenal medulla, liver and kidneys. Their selective activation lowers blood pressure without inducing sedation typical for alpha 2-agonists. Several substances binding with high selectivity to imidazoline receptors have recently been synthesized. Some of them as rilmenidine and moxonidine have successfully been introduced to the treatment of arterial hypertension in humans.

Adrenergic alpha-Agonists↗