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T Klupa

Publications and source records attributed to T Klupa.

14 recordsLinked to original sources
PubMed2006

Clinical risk factors and the role of VDR gene polymorphisms in diabetic retinopathy in Polish type 2 diabetes patients.

Evidence exists that some clinical, metabolic and genetic risk factors are associated with the development of diabetic retinopathy (DR). The aim of the study was: (1) to define the prevalence of DR in the examined group of 267 patients with type 2 diabetes mellitus (T2DM) from a Polish population; (2) to identify in cross-sectional analysis, the clinical features associated with DR in the study group; and (3) to search for the association of 4 markers of vitamin D receptor (VDR), a candidate gene for vascular complications in diabetes, with DR. The examined group consisted of 146 female and 121 male T2DM patients (mean age at examination: 61.3+/-9.4 years; age at T2DM diagnosis: 50.0+/-9.2; T2DM duration: 11.3+/-7.8 years; body mass index (BMI): 30.5+/-5.5 kg/m(2); HbA1c: 7.8+/-1.5%). In all patients, the clinical and metabolic profile was determined. Diagnosis of DR was determined by a trained ophthalmologist by ophthalmoscopy after pupillary dilatation. Colour photographic documentation was made. The examined T2DM patients were genotyped for FokI, ApaI, BsmI and TaqI frequent VDR polymorphisms based on the restriction fragment length polymorphism method. The statistical analysis was performed using univariate and multivariate logistic regression (SAS) and haplotype analysis (Haplostat). DR was detected in 85 (31.8%) patients with T2DM. The multivariate analysis revealed that significant predictors of this complication were: never-smoking status (odds ratio 2.2, 95% confidence interval 1.2-4), urea serum level (1.3, 1.1-1.5), HbA1c level (1.4, 1.1-1.8) and insulin treatment (2.7, 1.4-5.1). Other features such as age of T2DM diagnosis, T2DM duration prior to ophthalmic exam, obesity (BMI>30), serum creatinine level, albumin/creatinine ratio and arterial hypertension were univariate predictors of DR, however they lost significance as independent predictors in multivariate analysis. Similarly, the alleles, genotypes, haplotype and haplotype combination of VDR were not associated with the examined complication. However, there was a suggestion of a possible slight association between the fbaT haplotype and DR (p=0.11). In conclusion, our study showed that DR in T2DM patients remains a frequent complication in Polish T2DM patients. We were able to confirm the role of some clinical risk factors, surprisingly including not-smoking status, as was previously shown in the UK Prospective Diabetes Study (UKPDS). VDR gene polymorphisms did not constitute a risk factor for this size of study group.

Body Mass Index↗
PubMed2006

Polymorphisms in the gene encoding hepatocyte nuclear factor-4alpha and susceptibility to type 2 diabetes in a Polish population.

Recently, several association studies of type 2 diabetes mellitus (T2DM) and the hepatocyte nuclear factor (HNF)-4alpha gene were reported with conflicting results. Our aim was to search for association between two polymorphisms of HNF-4alpha and T2DM in Polish Caucasians. The study groups comprised of 461 T2DM cases and 366 controls. Genotype-quantitative trait analyses were based on the oral glucose tolerance test (OGTT), glucose and insulin results, and comprised 310 glucose-tolerant subjects. All individuals were genotyped for two HNF-4alpha polymorphisms. The frequencies of the minor alleles were as follows: 19.2% in T2DM vs. 17.6% in controls for rs2144908; and 20.6% vs. 20.1% for rs4810424, respectively. The distributions of alleles, genotypes, and haplotypes of the HNF-4alpha polymorphisms did not differ between the study groups (lowest P = 0.41). None of the examined SNPs showed an association in control subjects with quantitative traits of fasting plasma glucose, fasting insulin, as well as plasma glucose and insulin 2 hours after glucose load in OGTT. We conclude that both examined polymorphisms in HNF-4alpha are not associated with T2DM and prediabetic phenotypes in Polish Caucasian study groups of this size.

Blood Glucose↗
PubMed2003

The Ala45Thr polymorphism of BETA2/NeuroD1 gene and susceptibility to type 2 diabetes mellitus in a Polish population.

The BETA2/NeuroD1 gene product is a transcription factor, a member of a helix-loop-helix (HLH) family that is specifically expressed in the endocrine pancreas. HLH and homeobox proteins are involved in the development and function of pancreatic islets cells. Mice homozygous for a targeted disruption of BETA2/NeuroD1 showed abnormal pancreatic islet morphogenesis and developed overt diabetes. Mutations in the NeuroD/BETA2 gene were linked to the development of type 2 diabetes (T2DM). The aims of the study were to determine the allele and genotype frequency of Ala45Thr polymorphism of BETA2/NeuroD1 in a Polish population and to examine the role of this amino acid variant in the genetic susceptibility to T2DM. We included 394 individuals into this study: 223 T2DM patients with the age at diagnosis above 35 years and 171 controls without a family history of T2DM. The fragment of the gene, corresponding to the Ala45Thr amino acid variant, was amplified by polymerase chain reaction. Alleles and genotypes were determined based on electrophoresis of the specific restriction enzyme EcoI57 DNA digestion products. Differences in distribution between the groups were examined by chi(2) test. The frequencies of the Ala and Thr alleles in T2DM patients (62% and 37.9%) were similar to those in the controls (65.5% and 34.5%; p=0.32). Similarly, there was no difference between the groups when we analyzed the genotype distribution (p=0.24). The stratification analysis based on family history of T2DM, obesity, and age of diagnosis did not show any difference between the groups. In conclusion, the frequency of Ala45Thr polymorphism in this studied Polish population is similar to its frequency in other Caucasians. We did not find evidence that the Ala45Thr polymorphism of BETA2/NeuroD1 played a role in the risk of T2DM in the examined Polish population.

Adult↗
PubMed2003

Association study of the vitamin D: 1alpha-hydroxylase (CYP1alpha) gene and type 2 diabetes mellitus in a Polish population.

OBJECTIVES: Type 2 diabetes mellitus (T2DM) is a complex disease. Genetic and environmental factors cooperate together to form its clinical picture. Polymorphisms in genes involved in the metabolism of vitamin D may influence susceptibility to T2DM. One of them is the vitamin D 1alpha-hydroxylase (CYP1alpha) gene. In this study we searched for the association of two markers, one in its intron 6 and the another one located upstream from the 5' end of CYP1alpha gene, with T2DM in a Polish population. METHODS: Overall 522 individuals were included in this study: 291 T2DM patients and 231 controls. The sequences, which contain both examined variants, were amplified by polymerase chain reaction (PCR). The T-->C polymorphism in intron 6 was assessed by the dot-blotting method using P(32). Genotyping of the other variant in the 5' end of CYP1alpha gene was carried out by restriction fragment length polymorphism (RFLP) method. Since variants of both SNPs were in very strong linkage disequilibrium, haplotypes could be assigned to phase-unknown individuals. The distribution of alleles, genotypes, haplotypes and haplotype combinations was compared between the groups by chi(2) test. RESULTS: The frequency of T/C alleles of the 5'end variant was 81.7%/18.3% in T2DM patients and 82.8%/17.2% in the controls (chi(2)=0.2, 1.d.f., p=0.65). For a T-->C polymorphism in intron 6 the frequency of alleles was 65.1%/34.9% and 67.5%/32.5% in T2DM patients and controls, respectively (chi(2)=0.413, 1.d.f., p=0.669). Distribution of genotypes, haplotypes and haplotype combinations were similar in both groups. In stratified analysis, we observed that the T-C/T-T heterozygous haplotype combination was more prevalent in the subgroup of obese T2DM patients (BMI >=30) than in the controls (41.5% vs 28.6%, p=0.01). CONCLUSIONS: Vitamin D 1alpha-hydroxylase is not a major gene for T2DM in a Polish population. However, this gene may be associated with T2DM in subjects with obesity. Thus, to definitely determine the role of this gene in T2DM further studies are necessary in other populations using larger sample size.

Cytosine↗
PubMed2003

The Ala45Thr polymorphism of BETA2/NeuroD1 gene and susceptibility to type 1 diabetes mellitus in caucasians.

It has recently been shown that mutations in BETA2/NeuroD1 are responsible for the development of type 2 diabetes mellitus (T2DM) in Caucasians. This gene is located near the IDDM7 region and one of its amino acid polymorphisms, Ala45Thr, has been associated with type 1 diabetes (T1DM) in Japanese and Danish populations. The aim of our study is to examine Ala45Thr for its role in T1DM in Caucasians. We used both population-based case-control analysis and family-based transmission/disequilibrium testing (TDT). Genotyping was carried out by the dot-blotting method using P32. Study subjects comprised 202 type 1 diabetes cases (mean age at diagnosis: 11.1 years, mean age at examination: 36.4 years) and 139 controls with normal fasting glucose. For the TDT study, allelic transmission was evaluated in 209 case family trios. The frequency of the Ala45 allele was 70.3 % in cases and 62.9 % in controls (p=0.04), and 47.5 % of cases were Ala45 homozygotes compared to 36.0 % of controls (p=0.03). The TDT component of the study did not achieve statistical significance. However, given the high frequency of this variant even among controls, exceptionally large data sets are needed to provide adequate power for this approach. Our case-control study suggests that the Ala45 variant of BETA2/NeuroD1 may be associated with T1DM in Caucasians (or in linkage disequilibrium with a causative variant). However, this finding should be confirmed by a much larger family-based study.

Adult↗
PubMed2003

Vitamin D receptor gene polymorphisms and association with type 2 diabetes mellitus in a Polish population.

Vitamin D plays an important role in insulin secretion. There is also evidence that this steroid may influence the insulin sensitivity. Thus genes involved in its metabolic pathway have been regarded as good candidates for type 2 diabetes mellitus (T2DM). One of them is vitamin D receptor gene (VDR). Its multiple polymorphisms have been examined for the association with T2DM in several populations. Those studies did not provide clear answers about the role of VDR in this disease. The aim of the study was to search for the association of FokI, ApaI, BsmI, and TaqI polymorphisms of VDR gene with T2DM in a Polish population using a case-control study design. Overall, 548 individuals were examined: 308 T2DM patients and 240 control individuals. The study groups were genotyped for VDR FokI, ApaI, BsmI, and TaqI variants using the restriction fragment length polymorphism (RFLP) method. Since variants of ApaI, BsmI, and TaqI polymorphisms were in very strong linkage disequilibrium, three loci haplotypes could be assigned to phase-unknown individuals with a high degree of confidence. Differences in allele, genotype, haplotype, and haplotype combination distribution between the groups were examined by chi2 test. The VDR allele frequencies for T2DM patients and controls were as follows: FokI-F/f - 53.4 %/46.6 % vs. 55.2 %/44.8 %, BsmI-B/b - 34.4 %/65.6 % vs. 37.5 %/62.5 %, ApaI-A/a - 47.9 %/52.1 % vs 50.9 %/49.1 %, TaqI-T/t - 67.6 %/32.4 % vs. 62.7 %/37.3 %, respectively. There was no difference between the groups in allele frequency. Similarly, distribution of genotypes, three locus BsmI/ApaI/TaqI haplotypes and their combinations were similar in the groups. In conclusion, our study did not provide evidence for the association of four examined VDR polymorphisms with T2DM in a Polish population. We postulate that to fully determine whether the sequence differences in VDR gene are susceptibility variants for T2DM, additional studies in different populations are required in a large study group.

Adult↗
PubMed2001

Identification of a new mutation in the hepatocyte nuclear factor-1alpha gene in a Polish family with early-onset type 2 diabetes mellitus.

Recently, several genes associated with early-onset, autosomal dominant Type 2 diabetes (MODY) have been identified. Mutations in the hepatocyte nuclear factor (HNF)-1alpha gene seem to account for a substantial proportion of this type of diabetes in several populations. However, it is still of interest to estimate the frequency of HNF-1alpha mutations in various ethnic groups. The aim of our study was to determine the contribution of the HNF-1alpha gene to the development of MODY in a Polish population. We selected 15 families with MODY for this project. The 10 exons and promoter region of the gene were screened for sequence differences by direct sequencing of probands DNA. We detected 7 previously described polymorphisms that were not associated with diabetes. However, one sequence difference, a deletion of a cytosine in codon 225 in exon 3 (designated S225fdelC), was a new mutation resulting in a frame shift and synthesis of a nonsense peptide from amino acid 225 to 232 followed by the stop codon. Thus, the S225fdelC mutation effectively caused the loss of a part of the DNA binding domain and the entire transactivation domain. This mutation was present in 4 affected members of the family. They developed diabetes at an early age (mean age at diagnosis 23 yr) and were characterized by severely impaired insulin secretion. In addition, one family member who was not a carrier of the S225fdelC mutation was diagnosed with diabetes. Thus, he represents an example of phenocopy. In conclusion, we have identified a new HNF-1alpha variant that represents the first MODY mutation described in a Polish population. MODY3 mutations, including those in the exon 4 "hot spot", do not appear to be a very common cause of MODY in the Polish population.

Adolescent↗
PubMed2000

Further evidence for a susceptibility locus for type 2 diabetes on chromosome 20q13.1-q13.2.

We previously reported suggestive linkage between type 2 diabetes and markers in a region on chromosome 20q using data from a collection of 29 Caucasian families in which type 2 diabetes with middle-age-onset was segregated as an autosomal-dominant disorder. To map more precisely the susceptibility locus (or loci) within this broad region, we increased the family collection and genotyped all families for additional markers, both within the critical region and spaced over the rest of chromosome 20. Altogether 526 individuals (including 241 with diabetes) from the total collection of 43 families were included in the study. All individuals were genotyped for 23 highly polymorphic markers. Positive evidence for linkage was found for a 10-cM region on the long arm of chromosome 20q13.1-q13.2 between markers D20S119 and D20S428. The strongest evidence in two-point as well as multipoint linkage analysis (P = 1.8 x 10(-5)) occurred at the position corresponding to marker D20S196. The individuals with diabetes in the seven most strongly linked families had high serum insulin levels during fasting and 2-h post-glucose load periods. We did not find any evidence for linkage between type 2 diabetes and any other region on chromosome 20. In conclusion, our larger and more comprehensive study showed very strong evidence for a susceptibility gene for insulin-resistant type 2 diabetes located on the long arm of chromosome 20 around marker D20S196.

Aged↗
PubMed1999

Amino acid variants of the vitamin D-binding protein and risk of diabetes in white Americans of European origin.

BACKGROUND: Genetic variants of vitamin D-binding protein (DBP) have been reported to be associated, not only with diabetes, but also with prediabetic traits, in several populations. There are two known polymorphisms in exon 11 of the DBP gene that result in amino acid variants: at codons 416 GAT-->GAG (Asp-->Glu) and 420 ACG-->AAG (Thr-->Lys). OBJECTIVE: To examine the association of these polymorphisms with diabetes in white Americans of European origin. METHODS: We studied unrelated individuals: 181 with type 1 diabetes, 215 with type 2 diabetes, and 163 healthy controls. Exon 11 was amplified using polymerase chain reaction and the two alleles were determined by digestion with specific endonucleases: HaeIII and StyI, respectively. RESULTS: At codon 416, Asp/Glu allele frequencies were 45%/55% in patients with type 1 diabetes, 43%/57% in patients with type 2 diabetes, and 46%/54% in controls (chi(2)=0.69, 2 d.f., P<0.71). At codon 420, corresponding Lys/Thr frequencies were 27%/73%, 30%/70%, and 30%/70% (chi(2)=1.25, 2 d.f., P=0.53). Distributions of genotypes at both loci, and the haplotypes defined by the two loci, were also very similar in all groups. CONCLUSION: DNA polymorphisms in the DBP gene are not associated with diabetes in white Americans of European origin.

Adult↗
PubMed1998

[Apoptosis--from theory to practice].

Apoptosis-programmed cell death--is a process which has long been neglected in clinical thinking. Now we realize that it offers an understanding of a number of pathological conditions which otherwise cannot be explained. Moreover the analysis of the highly specific mechanisms of programmed cell death might aid in the development of new treatment strategies. In this paper we give the examples of the importance of apoptosis in the selected fields of clinical medicine. The knowledge of apoptosis in oncology, cardiology, endocrine diseases and others has achieved the level which enables its practical use. This is why we believe that apoptosis should attract attention of clinical practitioners.

Animals↗
PubMed1996

[Reactive gastritis in patients with diabetics with dyspeptic symptoms].

UNLABELLED: There is very few data on the prevalence of reactive gastritis (RG) in diabetes mellitus (DM). The typical histological findings in RG are foveolar hyperplasia, oedema with apparent diminution in glands, telangiectasia of lamina propria, a paucity of inflammatory cells. RG has been connected so far with a long term use of non-steroidal anti-inflammatory drugs (NSAIDs) or bile reflux, which is particularly frequent after cholecystectomy. RG is regarded as less frequently associated with the Helicobacter pylori (Hp) infection. The aim of the study was to define: 1. The prevalence of RG in diabetics with dyspeptic symptoms as compared with the non-diabetic group. 2. The prevalence of Hp infection in RG as compared with chronic active gastritis (CAG) in DM. 3. The association of these types of gastritis with autonomic neuropathy (AN). STUDY DESIGN: Gastroscopy was performed in 152 patients with symptoms related to upper alimentary tract disorders-52 with DM (13 with IDDM and 39 with NIDDM) and 100 without DM. The presence of RG, CAG and Hp infection was analysed in 3 biopsies. AN was evaluated in 35 diabetics in 4 cardiovascular tests using ProSciCard. RESULTS: RG was significantly more frequent in DM than in control group (10/52, 19.2% vs. 3/100, 3%, respectively, p < 0.01). This difference was preserved after excluding all patients with NSAIDs use or being after cholecystectomy (8/36, 22.2% vs. 2/81, 2.5%, respectively, p < 0.001). Hp infection in diabetics with RG was significantly lower than diabetics with CAG (2/10, 20% vs. 16/23, 69.5%, respectively, p < 0.05). AN was more frequent in diabetics with RG than with CAG (7/10, 70% vs. 6/15, 40%, respectively, p < 0.001). Hp infection in diabetics with RG was significantly lower than diabetics with CAG (2/10, 20% vs. 16/23, 69.5%, respectively, p < 0.05). AN was more frequent in diabetics with RG than with CAG (7/10, 70% vs. 6/15, 40%, respectively), the difference was not significant with this sample size. CONCLUSIONS: 1. RG seems to be more frequent in DM than in general population. 2. Hp infection is less frequent in RG than in CAG in DM. 3. The higher prevalence of RG in DM may result from impaired motility and reflux of bile caused by AN.

Adolescent↗
PubMed1995

[Corrected QT interval and diabetic neuropathy of the cardiovascular system].

UNLABELLED: Our objective was the analysis of the utility of the corrected QT interval (QTc) for the assessment of severity of cardiac autonomic neuropathy. Fourty nine patients with insulin-dependent diabetes mellitus/IDDM/were enrolled in the study. Their ages ranged between 16 and 58 years, and the duration of IDDM ranged between 1 and 38 years. Patients were tested for cardiac autonomic neuropathy using ProSciCard system. We carried out four tests: resting pulse deep breathing pulse Ewing test Valsalva maneuver Our results showed the relationship between the QTc interval lengthening and the occurance of cardiac autonomic neuropathy. No correlation was found between the QTc interval and the extend of cardiac autonomic neuropathy. CONCLUSIONS: The QTc interval measurement is a good routine test for the diagnosis of cardiac autonomic neuropathy. The corrected QT interval is not a reliable indicator of the extend of cardiac autonomic neuropathy.

Adolescent↗
PubMedDate not supplied

Search for mitochondrial A3243G tRNA(Leu) mutation in Polish patients with type 2 diabetes mellitus.

BACKGROUND: The influences of genetic and environmental factors form a clinical picture of type 2 diabetes mellitus. Genetic studies of type 2 diabetes mellitus become increasingly important. The knowledge of the molecular background of type 2 diabetes has been growing rapidly over recent years. One of the forms of the disease defined on the molecular level is maternally inherited type 2 diabetes mellitus. This diabetes, which is frequently accompanied by hearing impairment of deafness (maternally inherited diabetes with deafness-MIDD), was linked with sequence differences in mitochondrial DNA. The most frequent cause of MIDD is A3243G substitution in a mitochondrial tRNA(Leu) gene. While this mutation was identified in different races in several populations, it is still important and valuable to evaluate its prevalence in various ethnic groups. The aim of the project was to determine the prevalence of A3243G substitution in a mitochondrial tRNA(Leu) gene among Polish diabetic subjects. MATERIAL AND METHODS: In total 129 individuals, with type 2 diabetes and 12 with gestational diabetes were selected for this study. Two techniques based on restriction fragment length polymorphism (RFLP) method were used to screen for A3243G mutation. In the first approach, non-radioactive PCR reactions of mitochondrial DNA region of interest were performed using DNA of the study participants. This was followed by Apa I restriction enzyme digestion of the PCR product. Subsequently an electrophoretic separation was done on 2% agarose gel with ethidium bromide staining. In the second, more sensitive, modification of RFLP, [alpha 32P]dCTP was used for internal primer labeling and the electrophoresis was done on acrylamide gel. A positive sample was used to control the quality of the genotyping. RESULTS: In both approaches none of the samples, except for the positive control, showed the evidence of the G variant. CONCLUSIONS: In summary, the A3243G mutation in mitochondrial tRNA(Leu) gene is not a frequent cause of diabetes in the Polish population. Further screening of enlarging study group is necessary to fully determine the prevalence of this mutation in our population. This, together with the search for other mitochondrial mutations, should allow to fully determine the prevalence of MIDD and its specific molecular background in the Polish population.

Adult↗