Biomedical subjects

B Krahulec

Publications and source records attributed to B Krahulec.

At least 19 recordsLinked to original sources

PubMed2004

Effect of vitamin E supplementation on microalbuminuria, lipid peroxidation and blood prostaglandins in diabetic patients.

BACKGROUND: Oxidative stress is an important pathogenic factor in the development of diabetic vascular complications. AIMS: To study the effect of vitamin E supplementation on microalbuminuria, plasma levels of malondialdehyde (MLD) and metabolites of prostaglandins TXA2 (TXB2) and PGI2 (6-keto-PGF1alpha) and to evaluate the relation between plasma MLD and thromboxane B2 (TXB2) in diabetic patients. PATIENTS AND METHODS: Diabetic microalbuminuric patients were supplemented with vitamin E 1200 IU daily (EVIT, Rodisma, Germany) and measurements of microalbuminuria, MLD, TXB2 and 6-ketoPGF1alpha were repeated after 4 months of treatment. RESULTS: Vitamin E supplementation lowered microalbuminuria (93.8 +/- 45.6 vs 67.95 +/- 28.4 microg/min, p < 0.05), MLD (0.55 +/- 0.26 vs 0.32 +/- 0.16 micromol/l, p < 0.001) and also TXB2 level (115.14 +/- 22.7 vs 15.32 +/- 14.7 ng/l, p < 0.001) in diabetic microalbuminuric patients. The changes of 6-keto-PGF1alpha after treatment were not significant. CONCLUSIONS: Our results did not show any significant relationship between levels of MLD and TXB2. Vitamin E supplementation significantly lowered microalbuminuria, MLD and TXB2. (Tab. 2, Fig. 2, Ref. 35).

Albuminuria↗

PubMed2003

[Effect of vitamin E therapy on progression of diabetic nephropathy].

Pathogenesis of diabetic nephropathy, which belongs to most serious microangiopathic complications of diabetes, is still not completely clear. Thromboxan A2 and increased oxidation stress are new factors apparently associated with pathogenesis of diabetic nephropathy. It was the aim of the contribution to verify the participation of thromboxan A2 and oxidation stress in the pathogenesis of diabetic nephropathy, as well as to follow the effects of treatment with vitamin E on its progression. In 19 diabetic subjects with microalbuminemia (MA) (age 55.2 +/- 7.6 years), 10 diabetic subjects with normoalbuminemia (NA) (age 54.4 +/- 6.1 years) and in 10 healthy subjects (age 53.6 +/- 9.4) the authors examined the level of malondialdehyde (MLDA) in serum, metabolites of thromboxan A2 (thromboxan B2-TXB2) and prostacyclin PGI2 (6-keto-PGF1 alpha) in urine by means of an RIA method (Isotop, Hungary). The diabetic patients with microalbuminemia were subsequently administered natural vitamin E (EVIT, Rodisna, FRG) at the daily dose of 1200 IU for the period of four months. After two and four months, respectively, MA, MLDA, TXB2 and 6-keto-PGF1 alpha) were examined. The age of the subjects in the two groups was not significantly different. In diabetic subjects with MA, the authors observed significantly higher MLDA levels in serum than in the control individuals (0.55 +/- 0.26 vs. 0.22 +/- 0.02 mumol/l, P < 0.001) and a significant difference occurred also in TBX2 in urine (134.7 +/- 113.8 vs. 27.7 +/- 10.1 ng/12 h, P < 0.001). Increased levels of TXB2 in urine were already present in diabetic subjects with NA as compared with healthy individuals (69.1 +/- 38.8 vs. 27.7 +/- 10.1 ng/12 h, P < 0.05). The treatment with vitamin E caused a significant decrease of MA (93.8 +/- 45.6 vs. 67.95 +/- 28.4 micrograms/min, P < 0.05), MLDA in serum (0.55 +/- 0.26 vs. 0.32 +/- 0.16 mumol/l, P < 0.001). On the basis of our results it is possible to suppose the role of oxidation stress and increased level of thromboxan A2 in the pathogenesis of diabetic nephropathy. The authors also confirmed that the treatment with vitamin E favorably decreases microalbuminemia, while the nephroprotective effect is apparently mediated not only by the antioxidant action, but also the decrease of thromboxan A2 production.

Albuminuria↗

PubMed2003

Does diabetic autonomic neuropathy influence the clinical manifestations of reflux esophagitis?

Diabetic autonomic neuropathy is a common complication of diabetes mellitus and affects every segment of the gastrointestinal tract. Gastrointestinal problems tend to be more common and severe in diabetics compared with the nondiabetic population. In the literature, the prevalence of reflux esophagitis is not known. The aim of this study was to analyze esophagoscopic findings, compare them with esophageal symptoms, and evaluate reflux esophagitis in relationship with autonomic neuropathy. We examined 54 diabetics (15 type 1, 39 type II), 28 males and 26 females, average age 55.4 (95% confidence intervals 52.1-58.8), with duration of diabetes more than 5 (average 15.0; 12.4-17.6) years. All patients completed a structured questionnaire. After overnight fasting, gastroesophageal endoscopy was performed in the morning to establish the presence of reflux esophagitis, using the Los Angeles classification. Cardiovascular autonomic neuropathy was diagnosed with the help of cardiovascular autonomic reflexes (deep breathing, active orthostasis, Valsalva's maneuver) and spectral analysis of heart rate variation. Endoscopic esophagitis was present in 22 (40.7%) diabetics and 10 of them (45 %) also complained of reflux symptoms. Sensitivity of symptoms was 45.5% and specificity was 72%. We found the presence of symptoms of reflux esophagitis in 21 (38.9%) diabetics, but of this group only 10 (47.6%) had endoscopic changes. Autonomic neuropathy was present in 29 patients, 16 (55%) of them had reflux esophagitis and 18 (62%) were positive for reflux symptoms. In the diabetics without autonomic neuropathy, esophagitis was noted in 6 (24%), which reflects a significant difference (p < 0.05). Reflux symptoms were present in 10 (40%) diabetics without autonomic neuropathy, and in comparison with patients who had autonomic neuropathy, the difference was not statistically significant. Thus, reflux eosophagitis is common in diabetic patients, with a prevalence of 40.7%. Reflux symptoms do not have a great diagnostic value in establishing reflux esophagitis. We confirmed a relationship between autonomic neuropathy and the clinical manifestations of reflux esophagitis, but no association with accompanying reflux symptoms. (Tab. 2, Ref. 27.)

Autonomic Nervous System Diseases↗

PubMed2002

The effect of cardiovascular autonomic neuropathy on resting ECG in type 1 diabetic patients.

BACKGROUND: Cardiovascular autonomic neuropathy (CAN) is a common complication of diabetes mellitus. AIM: To assess the manifestations of CAN on ECG at rest. SUBJECTS AND METHODS: 100 type I diabetic patients, mean age 36.5 (range 17-62) years, mean duration of diabetes 14.6 (range 0-49) years were examined. The control group consisted of 88 healthy subjects, mean age 37 (range 15-65) years. Cardiovascular reflexes (respiration sinus arrhythmia, orthostatic test and Valsalva's maneuvre) were examined, and ECG at rest was analysed. RESULTS: In 35 (35%) diabetics CAN was established. In comparison to diabetic patients without neuropathy, patients with CAN had a higher heart rate (94, 89-99 vs. 79, 75-82 heart beats.min-1, p < 0.001), higher P wave voltage (0.13, 0.12-0.15 vs 0.11, 0.09-0.12 mV, p < 0.001), as well as QTc interval length (422, 410-433 vs 396, 388-404 ms, p < 0.001), but they had a lower voltage of R wave (0.83, 0.72-0.94 vs. 1.0, 0.91-1.09 mV, p < 0.05) and lower T wave voltage (0.18, 0.15-0.21 vs 0.23, 0.19-0.27 mV, p < 0.05). CONCLUSIONS: The higher voltage of P wave, lower voltage of T wave, shorter PQ interval and prolonged QTc interval with tachycardia may be the manifestation of relative sympatheticotonia. Lower R wave voltage and the prolonged QRS complex are the possible signs of cardiomyopathy. (Tab. 4, Ref. 31.)

Adolescent↗

PubMed2002

[Incidence of risk factors and vascular complications in patients with newly diagnosed type 2 diabetes mellitus].

UNLABELLED: The objective of the investigation was early detection of risk factors of diabetes and/or atherosclerosis and the prevalence of vascular complications of diabetes in newly diagnosed patients with type 2 diabetes in the Slovak Republic. PATIENTS AND METHODS: In the Slovak detection programme of vascular complications participated 40 diabetological out-patient departments. In the course of one year (from the beginning of June 1999 to the end of May 2000) in a total of 3424 newly diagnosed patients with type 2 diabetes, aged under 70 years the case-history was recorded, focused on risk factors of diabetes and atherosclerosis, on the patients' lifestyle, on vascular complications of diabetes and their treatment. Moreover a detailed clinical and laboratory examination was made. The authors made in addition to assessment of the blood sugar level also biochemical examinations focused on indicators of the lipid metabolism and microalbuminuria. All patients had an ophthalmological examination, and the electrocardiogram was recorded. RESULTS: As to risk factors of diabetes as many as 3259 patients (95.2%) reported a low physical activity (exercise lasting less than the minimum of 3 x 30 minutes per week) and 3001 (87.6%) had an elevated body weight, whereby 43.9% patients had a BMI of 25 to 30 kg/m2 and 43.8% were obese (BMI > 30 kg/m2). Diabetes mellitus in a first grade relative was reported by 1521 patients (44.7%). As to risk factors of atherosclerosis, the most frequent finding was hyprcholesterolaemia (values > 5.2 mmol/l) in 2262 patients (67.3%), and hypertriglyceridaemia (values > 1.7 mmol/l) in 2194 patients (66.5%). Arterial hypertension (values of systolic and/or diastolic pressure > 140/90 Hg) were recorded in 2326 (67.9%) patients. The most frequent microvascular complication of diabetes was microalbuminuria was in 20.5% patients. Ischaemic heart disease was recorded in 22.80 diabetics. Risk factors of atherosclerosis and vascular complications in newly diagnosed type 2 diabetics are closely related to the patients' body weight. CONCLUSION: The authors provided evidence of a high incidence of risk factors of diabetes and atheroscleosis in newly diagnosed patients with type 2 diabetes mellitus, and in practically every fifth patient the presence of ischaemic heart disease. Obesity is a significant adverse metabolic and vascular factor.

Adolescent↗

PubMed2000

[Effect of vitamin C and E on nonenzymatic glycation and physico- chemical properties of isolated erythrocyte membranes in diabetic patients].

Non-enzymatic glycation, accompanied by the formation of free radicals, represents a serious problem in diabetes mellitus. It is supposed to be the cause of the development of long-term diabetic complications. The aim of this work was to estimate the effect of treatment with vitamin C (1 g per day) and E (600 mg per day) on selected biochemical parameters as well as to determine the physicochemical state of erythrocyte membranes in diabetics. The paper also compares the physicochemical state of diabetic and control erythrocyte membranes. The changes in the values of glycaemia, glycated haemoglobin, and fructosamine were insignificant after three months of treatment. This points out that the doses used could be low or that the patient compliance was poor. An anionic fluorescent probe merocyanine 540 (MC540) was used to monitor possible changes in the physicochemical properties of isolated diabetic erythrocyte membranes. Significantly higher affinity of MC540 monomers to the membrane in diabetics treated with vitamin E was observed, which can be the result of the antioxidative effect of the vitamin (p < 0.02). A comparison of absorption spectra of MC540 in diabetic and control membranes revealed significant changes in the position of the bands and in their absorbances (p < 0.01 and less). They result from substantial alterations in the structure, surface charge, and the fluidity of erythrocyte membranes in diabetes mellitus. (Tab. 2, Fig. 3, Ref. 22.)

Antioxidants↗

PubMed2000

[Diabetic neuropathy].

Author in his article shortly describe pathogenetic mechanisms, clinical manifestations, diagnostic procedures and screening possibilities (which are very easy to perform), and also therapeutic methods of diabetic neuropathy.

Diabetic Neuropathies↗

PubMed2000

Decreased fluidity of isolated erythrocyte membranes in type 1 and type 2 diabetes. The effect of resorcylidene aminoguanidine.

Changes in the physico-chemical properties of erythrocyte membranes induced by nonenzymatic glycation as well as the possible prevention of their rise were studied. Using the fluorescent probe 1,6-diphenyl-1,3,5-hexatriene (DPH), fluorescence anisotropy values were determined in erythrocyte membranes isolated from type 1 and type 2 diabetic patients with and without complications. The mean anisotropy values for the groups of diabetic patients were significantly higher than those for the control group (p < 0.01). This indicated pathologically decreased fluidity in cell membranes in the diabetics regardless of the type of diabetes or the presence of complications. The fluorescence anisotropy positively correlated (p < 0.01) with clinical parameters, such as glycohaemoglobin and plasma cholesterol content, which are important for the monitoring of the compensation status of the diabetic patient. Our results support the suggestion that protein crosslinking and oxidative stress induced by nonenzymatic glycation contribute to changes in the physico-chemical properties of erythrocyte membranes. In vitro testing of a new potential drug resorcylidene aminoguanidine (RAG) showed its ability to increase significantly (p < 0.001), to various extent (p < 0.01), the fluidity of both diabetic and control erythrocyte membranes. Upon the administration of RAG, reduced fluorescence anisotropy values for the groups of diabetic patients approached the normal values obtained for the controls. This may play an important role in the improvement of impaired cell functions found in diabetes that are controlled by the cell membrane.

Adult↗

PubMed1999

Inhibition of nonenzymatic protein glycation and lipid peroxidation by drugs with antioxidant activity.

We studied the effects of aminoguanidine (AG), beta-resorcylidene aminoguanidine (RAG), DL-penicillamine (PNCA) and captopril on early and advanced glycation of human serum albumin (HSA). We also assessed inhibition of lipid peroxidation by AG and RAG in erythrocytes. Incubation of HSA with D-glucose (20 mM, 37 degrees C for 21 days) led to the formation of Amadori products and fluorescent advanced glycation end-products (AGE). Only PNCA markedly reduced the formation of Amadori products, while all tested compounds markedly reduced the formation of AGE. AG and RAG also inhibited malondialdehyde formation in erythrocytes incubated with hydrogen peroxide. Addition of AG at concentrations from 1 microM to 1 mM caused a 10-80% inhibition of lipid peroxidation. Thus, AG and RAG inhibit toxic oxidative processes and may have therapeutic potential in a number of human diseases.

Aged↗

PubMed1996

[Comparison of insulin loss in treatment of diabetics using the classical syringe or the insulin pen (Novopen II)].

The aim of the study was to investigate changes in insulin wastage when transferring patients from vial insulin to Actraphane HM Penfills and NovoPen II. Twenty four diabetic patients, were treated with Actraphane HM 40 IU/ml vial for 3 months, then transferred to Actraphane HM Penfill and NovoPen II for further 3 months. Wastage 1 (difference between insulin consumption and the total prescribed dose) was higher in vials than in Penfills (268.7 +/- 69.4 IU/3 months/patients vs. -7.6 +/- 30.2 IU/3 months/patient, p < 0.001 mean +/- SEM). Wastage 2 (insulin remaining in the container when discharged) was higher in the Penfills than in vials (214.1 +/- 22.04 IU/3 months/patient vs 45.2 +/- 11.2 IU/3 months/patient). Total wastage was 313.9 +/- 67.8 IU/3 months/patient (3.96 IU/day/patient) when using vials and 206.5 +/- 31.2 IU/3 months/patient (2.52 IU/day/patient) when using Penfills (NS). Higher wastage in vials may relate to a larger volume used for "airshot", and to a larger imprecision in the measured and injected dose when using vials. The latter may also be reflected in a significantly higher average incidence of weighted hypogiycemias in the vial period (15 +/- 4.28/3 months/patient) compared to the Penfill period (5.1 +/- 1.2/3 months/patient, p < 0.01). Total wastage was seen to be 29% smaller by using NovoPen II and therefore saving of insulin seems to be possible (approximately 1.44 IU/day/patient).

Adult↗

PubMed1995

[A 2-month period of physical training in insulin-dependent diabetics].

Twenty type 1 diabetics participated after previous individual instructions in a 8-week physical training programme. The latter comprised three training units per week. One training unit started by 10-minute warming up exercise, then the patients pedalled on a bicycle ergometer 2 x 10 minutes with a 5-minute break with a load amounting to 80% of the oxygen consumption during the maximum tolerated load. The final part was formed by swimming in a swimming pool, covering a distance of at least 200 m. After the termination of the programme the authors did not observe significant changes in the carbohydrate and lipid metabolism nor in physical performance, however, the maximal oxygen consumption increased as a result of training by 17% and the maximum achieved load by 25 W (i.e. one step). Throughout the investigation period the authors did not record any serious complications. The patients enjoyed the physical activity and reported improvement of the quality of life. Therefore the authors recommend physical training in the treatment of insulin-dependent diabetic patients.

Adult↗

PubMed1995

[Patient education in the metabolic syndrome].

In the treatment of the metabolic syndrome which comprises the most serious risk factors of atherosclerosis education is a basic prerequisite of treatment and prevention of complications. In the submitted review the authors analyze basic procedures of education from the general aspect as well as in individual disorders and diseases which characterize the metabolic syndrome (dyslipoproteinaemia, obesity, diabetes mellitus and impaired glucose tolerance, hypertension). They emphasize that a comprehensive change of the patient's life style and the life style of his whole family is necessary. This cannot be achieved within a short time and therefore motivation of the patient as well as of the health professionals engaged in the educational work is essential.

Arteriosclerosis↗

PubMed1991

[The importance of albuminuria in the detection of diabetic nephropathy and its relation to the development of retinopathy and autonomic neuropathy in type I diabetes].

A series of 72 type I diabetics was grouped according to the mean value of 24-h albuminuria (AU) determined from three 24-h urine collections: group A (n = 49, normoalbuminuria, AU less than or equal to 26 mg/24 h), group B (n = 16, microalbuminuria, AU less than or equal to 26 mg/24 h), group C (n = 7, clinically significant proteinuria, AU greater than 260 mg/24 h). Glycosylated hemoglobin (GHb) was examined five times in three-month intervals. Systolic and diastolic blood pressure (BPs and BPD) were determined from four values taken in the course of one year. Glomerular filtration (GF) was established a single examination of 24-h creatinine clearance. Fluorescent angiography was used to examine the fundus of the eye. The function of the cardiovascular autonomic nervous system was assessed on the basis of three tests: variation of heart rate during deep respiration, response of heart rate to upright position, Valsalva's maneuver. Group C had the longest duration of diabetes, the highest GHb, the lowest GF, and the highest BPS and BPD values. The number of diabetics with different findings on the fundus of the eye (normal finding/simple retinopathy/preproliferative and proliferative retinopathy) was as follows: group A--15/31/3, group B--9/6/1, group C--0/3/4. Group C exhibited the most pronounced derangement of the cardiovascular autonomic nervous system, whose extent depended on the length of diabetes duration and on the quality of metabolic compensation. Between the groups A and B no significant differences were found in any of the parameters studied.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗

PubMed1989

[Prolonged Q-T interval on the ECG at rest in type I diabetics with autonomic neuropathy].

86 type I diabetics and 60 healthy persons were examined. The diabetics were divided into two groups: patients with and without autonomous neuropathy. An analysis was made of heart rate, Q-T interval from 12-lead ECG at rest as well as of systolic pressure in each group of the patients. The diabetics with autonomous neuropathy had both systolic pressure and heart rate significantly higher and resting ECG Q-T interval longer than those of diabetics without autonomous neuropathy or than those found in healthy persons. These manifestations are most probably due to relative sympathicotonia in these patients. It results in increased left ventricular work and in a potential increase in arrhythmias which probably worsen the prognosis in diabetics with autonomous neuropathy.

Adult↗

PubMed1988