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M Samánek

Publications and source records attributed to M Samánek.

At least 19 recordsLinked to original sources
PubMed2002

[Consumption of white wine retards development of atherosclerosis and affects anticoagulation].

BACKGROUND: An inverse relationship between moderate alcohol use and coronary heart disease was found in various countries. Aims of the study were to find out whether drinking of moravian white wine will have the same effect on lipoproteins and fibrinogen as described in foreign wines. Blood pressure, body mass, blood glucose and a hepatic enzyme were also measured before and after drinking. METHODS AND RESULTS: Drinking of the Moravian white wine (vintage 1999; alcohol 11.48 vol %) was studied in 50 men aged 44.4 (SD 9.25) years. Drinking of 350 ml (40.2 g of alcohol) every evening for four weeks without any change of dietary factors followed in 45 men by statistically significant increase in HDL cholesterol from 1.17 to 1.25 mmol/l (p < 0.001) and free HDL cholesterol from 0.17 to 0.20 mmol/l (p < 0.0001) and highly significant (p < 0.00001) decrease in plasma fibrinogen level from 3.77 to 3.35 g/l. Nor triglycerides, or blood glucose and BMI were changed after increasing source of carbohydrates in wine. Mean systolic blood pressure of 123.4 mmHg did not change and diastolic blood pressure decreased insignificantly from 78.0 to 76.7 mmHg. Minimal decrease of ALT from 0.60 to 0.59 mukat/l disproved any hepatic disturbance. CONCLUSIONS: Everynight moderate drinking of Moravian white wine has similar beneficial effect as consumption of foreign alcohol drinks.

Adult↗
PubMed2001

Ontogenetic development of energy-supplying enzymes in rat and guinea-pig heart.

The purpose of the present study was to compare the ontogenetic development of the activity of myocardial energy-supplying enzymes in two mammalian species, differing significantly in their level of maturation at birth. The animals were investigated during the late prenatal period and 2, 7, 14, 21, 25, 30, 63, 120 and 730 days after birth in the rat and 2, 21, 84 and 175 days in the guinea-pig. The following enzymes were assayed in the right and left ventricular myocardium: lactate dehydrogenase (LDH, lactate uptake and/or formation), triose phosphate dehydrogenase (TPDH, carbohydrate metabolism), glycerol phosphate dehydrogenase (GPDH, glycerol-P shuttle)), hexokinase (HK, glucose phosphorylation), malate dehydrogenase (MDH, tricarboxylic cycle), citrate synthase (CS, tricarboxylic cycle) and hydroxyacyl-CoA dehydrogenase (HOADH, fatty acid breakdown). The rat heart, highly immature at birth, exhibits three different developmental patterns of energy-supplying enzymes, identical in both ventricles: (i) two mitochondrial enzymes of aerobic metabolism (CS, HOADH) and GPDH have a relatively low activity at the end of prenatal life; thereafter their activity steadily increases, approaching the adult levels between the 3rd and 4th postnatal weeks. A significant decrease was observed between the 4th and 24th months. (ii) MDH and LDH: prenatal values were significantly higher as compared with the 2nd postnatal day; after this period the activities increased up to adulthood (4 months) and decreased during senescence. (iii) The activities of HK and TPDH are characterized by only moderate changes during development. HK differs from all other enzymes by the highest prenatal values, which exceed even adult values. In contradiction to the rat heart, the developmental differences in more mature guinea-pig heart were significantly less pronounced. The only ontogenetic differences observed were the lower activities of enzymes connected with aerobic metabolism at the end of the prenatal period. Our results point to possible differences in the development of adaptive metabolic pathways in animals with different levels of maturation at birth.

3-Hydroxyacyl CoA Dehydrogenases↗
PubMed2000

[Does moderate alcohol drinking decrease the incidence and mortality rate in ischemic heart disease?].

Moderate drinking of alcohol decreases the progress of atherosclerosis, cardiovascular morbidity and mortality rate and total mortality. The mechanisms of action have not been clarified yet, but changes of lipid metabolism, antioxidative effect and changes in hemostasis are accused to play the major role. Moderate drinking leads to the increase of HDL cholesterol and decrease of LDL cholesterol. Antioxidants are distributed throughout the skin of grapes and therefore are present in higher concentration in red wine. Alcohol decreases the fibrinogen level and increases tPA, inhibits platelet aggregation and reduces factor VIIc. It positively influences stress, fear, anxiety and depression. Optimal daily consumption should be 20 to 40 g in men and half of it in women. Everyday drinking is important. There is no big difference between drinking beer, wine or drinks. The most crucial is to keep the moderate level of consumption.

Alcohol Drinking↗
PubMed1998

[What was not included in the recommendations for the diagnosis and therapy of hyperlipoproteinemia in childhood].

Screening and treatment of hyperlipidaemia should be the concern of paediatricians. This is suggested by the finding of fatty streaks and other atheromatic changes in children. The authors prefer selective to nationwide screening in children who have close relatives with coronary heart disease or cerebral haemorrhage before the age of 55 years in men and 65 years in women or elevated total cholesterol levels. In case of repeated total cholesterol levels of 4.4-5.2 mmol/l the authors recommend annual, in case of levels above 5.2 mmol/l 3-6 month intervals between examinations. The authors found values above 5.2 mmol/l in one quarter of otherwise healthy children. In addition to the hyperlipidaemic theory there is the infectious theory of development of atherosclerosis and the theory of programming of coronary heart disease during pregnancy. By dietary and lifestyle provisions it is possible to reduce hyperlipidaemia in the great majority of children. In boys above 10 years and girls above 20 years resins are indicated if the total cholesterol level is above 8 mmol/l.

Adolescent↗
PubMed1998

High-density lipoprotein subclasses and esterification rate of cholesterol in children: effect of gender and age.

Since the development of coronary heart disease (CAD) is affected by a specific pattern of plasma high density lipoprotein (HDL) effects it may be useful to know whether this occurs already in childhood. In this study we evaluated particle size distribution of HDL by gradient gel electrophoresis and the determination of cholesterol esterification rate (FER(HDL)) in plasma depleted of apo B lipoproteins in 221 children (108 boys and 113 girls) aged 4 months to 20 years. Total plasma- (TC), low-density lipoprotein- (LDL-C) and HDL- (HDL-C) cholesterol, HDL unesterified cholesterol (HDL-UC) and plasma triglycerides (TG) were also measured. There were no significant gender and age differences with respect to the plasma TC, LDL-TC and TG but concentration of HDL-TC increased with age. Post-pubertal girls had significantly higher relative concentrations of HDL2b compared to boys (30.4% vs 17.2%), while HDL3b,c was lower in post-pubertal girls (8.7% vs. 16.5%). FER(HDL) correlated inversely with HDL2b and positively with HDL3b,c particles and was significantly higher in boys of the post-pubertal group compared to girls (16.9%/h vs 12.5%/h). While in girls there was a positive correlation between age and HDL-C, HDL-UC and the relative concentration of HDL2b no significant correlation were observed in boys. In girls the increase in TC showed a significant correlation with a simultaneous increase in HDL-C, HDL-UC and HDL2b. In boys TC correlated significantly with changes in TG only. When HDL2b and HDL3b,c cholesterol levels are calculated from HDL-C concentration and per cent distribution the differences between males and females are further emphasized. These data indicate that HDL particle size distribution is age- and gender-dependent.

Adolescent↗
PubMed1998

Pulmonary function in children with atrial septal defect before and after heart surgery.

OBJECTIVE: To test the effect of heart disease and heart surgery on lung function. DESIGN: A pulmonary function study of children undergoing surgery for atrial septal defect (ASD). SETTINGS: University hospital. PATIENTS: 26 children tested before surgery (at mean (SD) age 11.8 (3.8) years) and 24 patients tested 1.8 (0.2) years after surgical correction. METHODS: Lung volumes, lung elasticity, and airway patency indices were measured using standard techniques. RESULTS: Before surgery: pulmonary function test abnormalities were found in 18 of the 26 patients. Stiff lung was found in 12, lung hyperinflation in five, and indices of decreased airway patency in four. Total lung capacity decreased in only two patients. After surgery: pulmonary function test abnormalities were found in 12 of the 24 patients (informed consent not given for two patients). Stiff lung was detected in nine and indices of peripheral airway obstruction in four. Mean values of specific airway conductance and peak expiratory flow were all normal. Lung hyperinflation was found only in one of 24 patients. No correlation between perioperative events and pulmonary function test data was found. CONCLUSIONS: Pulmonary function test abnormalities persist in half the patients almost two years after surgery for ASD. A decrease in the total frequency of pulmonary function test abnormalities (in 19% of the patients), with a decrease in stiff lung in 8% and lung hyperinflation in 15%, was not significant. Impairment of lung function related to ASD is associated with the disease itself rather than the surgical procedure.

Adolescent↗
PubMed1997

[Cholesterol and triglyceride levels and their development from 2 to 17 years of age].

BACKGROUND: High blood cholesterol levels is important risk factor of an early atherosclerosis and ischemic heart disease. Information on cholesterol level in children in essential for grading the risk and following its trends in the Czech population and for starting an effective prevention already in childhood. METHODS AND RESULTS: Fasting venous cholesterol and triglyceride levels were measured in 1378 children and adolescents, 707 boys and 671 girls aged 1-17 years. Children with familiar hypercholesterolemia or with another illness influencing the measured data were excluded. The mean total cholesterol (TC) level was 4.46 +/- 0.92 mmol/l. It increased from the youngest age, culminated at the age of 13 and decreased afterwards. Mean HDL cholesterol value was 1.23 mmol/l. The lowest value was measured in the youngest age group. The highest values were reached at the age of 11 years and later. TC/HDL ratio was higher than 4.0 only between the age of 3 and 5. LDL cholesterol mean value was 2.70 +/- 0.92 mmol/l. The lowest values were found between 1 and 3 and 13 to 17 years. Triglyceride mean value was 1.22 +/- 0.79 mmol/l. It ranged from 1.53 mmol/l in the youngest age group to 1.03 mmol/l at the age of 7 to 9 years. The values in boys did not differ from those in girls. TC was higher in children with an increased body mass than in children with normal body weight. We did not prove any regional difference in the measured values. CONCLUSIONS: The desired TC value (< 4.41 mmol/l) was found in only 52% of children. In total 18% of all probands, but 26% of school age children belong into high risk category with TC above 5.20 mmol/l.

Adolescent↗
PubMed1997

Good exercise tolerance and impaired lung function after atrial repair of transposition.

OBJECTIVE: Evaluation of long-term results of atrial correction of transposition of the great arteries (TGA), focusing on the relationship between pulmonary function and exercise tolerance. METHODS: A prospective population-based study-56 out of 60 survivors of Mustard/Senning repair, born in Bohemia in 1980-1984 (median age at surgery 0.85 years) were followed up over 13.4 +/- 1.2 years and studied by complete lung function and bicycle exercise testing. RESULTS: Maximum heart rate on exercise reached 181 +/- 14 bpm (Z-score: -1.06 +/- 1.66, range -6.7 to +1.6); VO2max: 40.6 +/- 6.7 ml/kg per min (Z-score: -0.97 +/- 1.4, range -5 to +1.8). A total of 73.6% had abnormal lung function, most frequently features of stiff lung (39.6%) and lung restriction (32.1%). Static recoil pressure of the lungs measured at 100, 90 and 60% of total lung capacity reached 137, 126 and 130%, respectively (Z-score: 1.93 +/- 2.33, 1.64 +/- 1.96, and 1.14 +/- 1.95, respectively). There was an inverse relationship between static recoil pressure of the lungs and VO2max (r = -0.306, P = 0.043), indicating the impact of lung function abnormalities on exercise tolerance. Comparison with lung function study of the group of 'pioneer' Mustard patients operated at the mean age of 4.4 years revealed a similar pattern and frequency (73.6% in current series vs. 88%, NS). CONCLUSIONS: Long-term follow-up has shown good exercise tolerance in the majority of patients after atrial correction of TGA performed in infancy. Many of them, however, have impaired lung function, especially stiff lung, although less frequently than original patients operated at a later age. The stiff lung can impair the exercise tolerance.

Analysis of Variance↗
PubMed1997

Long-term ventricular performance after intra-atrial correction of transposition: left ventricular filling is the major limitation.

OBJECTIVE: To establish the incidence of systolic and diastolic dysfunction of the right and left ventricle in a large cohort of patients after Mustard or Senning operations and to assess changes in the incidence on long term follow up. DESIGN: Postoperative case-control study using radionuclide ventriculography. Ejection fractions, peak filling rates, rapid filling periods and fractions, slow filling periods and fractions, and atrial contraction periods and fractions were studied. SETTING: Tertiary care centre, ambulatory and hospital inpatient care. PATIENTS: A convenience sample of 153 patients studied at median age of 6.9 years (median 4.4 years after surgery). In 99 cases another study was available at a median age of 15.3 years (median 13 years after surgery and 8.8 years after the first study). RESULTS: Respective incidences of dysfunction in the first and the second study were as follows: ejection fraction-right ventricle 7.8% and 8.1%, left ventricle 7.2% and 10.1%: peak filling rate-right ventricle 0% and 4.2%, left ventricle 14.3% and 29.5% (p < 0.05); rapid filling period-right ventricle 18.3% and 11.6%, left ventricle 30.2% and 30.5%; slow filling period-right ventricle 4.8% and 3.2%; left ventricle 11.9% and 23.2%; atrial contraction period-right ventricle 0.8% and 4.2%, left ventricle 15.1% and 26.3%; rapid filling fraction-right ventricle both 0%, left ventricle 82.5% and 79.0%; slow filling fraction-right ventricle 0.8% and 4.2%, left ventricle 37.3% and 30.5%; atrial contraction fraction-right ventricle both 0%, left ventricle 79.4% and 71.6%. CONCLUSIONS: The incidence of systolic ventricular dysfunction is 8% (right ventricle) and 10% (left ventricle) 13 years after surgery, without a significant increase over the eight year follow up. Diastolic filling is abnormal in up to 80% of patients and left ventricular peak filling rate deteriorates with time.

Adolescent↗
PubMed1995

Seven-year experience of noninvasive preoperative diagnostics in children with congenital heart defects: comprehensive analysis of 2,788 consecutive patients.

The spectrum of patients operated on without preoperative catheterization and angiography, the accuracy of echocardiographic diagnosis and its impact on the results of surgical treatment were prospectively assessed in 2,788 children consecutively operated for congenital heart defects (CHD) between 1986 and 1992. The overall percentage of surgery based solely on noninvasive preoperative examination increased from 63% in 1986 to 81% in 1990 and decreased to 72% in 1992. There were no differences in the preoperative diagnostic approach between groups of newborn, infants and children. A high percentage of patients with patent ductus arteriosus (96.5%), atrial septal defect (94%), incomplete atrioventricular septal defect (88.6%), ventricular septal defect (86.3%), coarctation of the aorta (80.2%) and total anomalous pulmonary venous connection (79.3%) was referred for surgery without prior invasive examination, while a lower percentage was found in univentricular heart (48.4%), pulmonary atresia (34.6%) and double outlet right ventricle (27.7%). More patients with pulmonary and tricuspid atresia were catheterized before complete repair compared to those who underwent palliative surgery (p < 0.01 and p < 0.0001, respectively). The echocardiographic diagnosis was correct in 96% of patients. Two patients of those with incomplete preoperative diagnosis died early postoperatively, both with missed apical ventricular septal defect. One with tetralogy of Fallot died after reoperation, the other with persistent truncus arteriosus due to sepsis. When the echocardiographic findings are in full agreement with the clinical status, physical examination, ECG and chest X-ray, we recommend cardiac surgery without prior catheterization in many patients with CHD.

Adolescent↗
PubMed1993

[The effect of therapy with adrenergic beta receptor blockers on myocardial beta adrenergic receptors in children with tetralogy of Fallot].

Seventeen children with tetralogy of Fallot undergoing cardiac surgery were investigated for alteration in myocardial beta-adrenergic receptors (BAR) in dependence on the previous chronic administration with the beta-adrenergic blocker metipranolol. Binding parameters, Bmax (maximal binding capacity) and Kd (dissociation constant), in right ventricular tissue were assessed in direct saturation binding studies using 125I-pindolol. It can be concluded that a) chronic administration of metipranolol to nine patients in usual doses did not change either Bmax or Kd of BAR in the samples of right ventricle, and b) twelve hours interval between last dose of metipranolol and removal of tissue samples is sufficiently long to enable normalization of possible changes in the sensitivity of BAR. This finding is supported by the pot-operative course and the response to dopamine which did not differ in patients treated and untreated with metipranolol in the preoperative period. Thus, our results suggest that there is no apprehension of chronic application of beta-blockers in patients with tetralogy of Fallot which would negatively influence the response to dopamine during the operation and in the postoperative period.

Child, Preschool↗
PubMed1993

Protein profiling of human atrial and ventricular musculature: the effect of normoxaemia and hypoxaemia in congenital heart diseases.

Samples of myocardial tissue were obtained during surgical intervention from children operated for different types of congenital heart disease (tetralogy of Fallot, ventricular and atrial septal defect). Sarcoplasmic, contractile and collagenous proteins were isolated by stepwise extraction from the both right ventricular and atrial musculature. It has been found that: a) the concentration of contractile proteins is significantly higher in the ventricles, b) the concentration of collagenous proteins is significantly higher in the atrium, c) the concentration of sarcoplasmic proteins was not different, d) in children with chronic hypoxia the above atrio-ventricular differences persisted. Moreover, the proportion of the soluble collagenous fraction in the atria was significantly increased.

Adolescent↗
PubMed1993

Differences between atrial and ventricular energy-supplying enzymes in five mammalian species.

The purpose of this study was to compare a pattern of 7 enzymes of energy-supplying metabolism in atrial and ventricular myocardium in some mammalian species. Tissue samples of right and left atria and ventricles were obtained from adult male rats, guinea-pigs, rabbits, dogs and pigs. The results clearly demonstrate significant differences in enzyme activities between the atria and ventricles in all these species. In the atria the activity of enzymes connected with aerobic and lactate metabolism (hydroxyacyl-CoA-dehydrogenase, citrate synthase, malate dehydrogenase and lactate dehydrogenase) was markedly lower than in ventricles. On the other hand, in rats, dogs and pigs glucose phosphorylation capacity (hexokinase) was approximately the same in atrial tissue as in ventricles. Right-to-left metabolic differences were much less expressed; conspicuous was only the higher activity of hydroxyacyl-CoA-dehydrogenase in the left atria and ventricles of guinea-pigs and rabbits indicating higher fatty acid utilization capacity in the left heart.

Animals↗
PubMed1992

Children with congenital heart disease: probability of natural survival.

The age distribution of death in all children with congenital heart disease (CHD), who died in a 27-year period in Central Bohemia (population of 1.2 million), and the data on the incidence of CHD in children born in Bohemia (population of 6.3 million) in 1980 were used to calculate the probability of survival of a child born with CHD. Eighty-six percent of these children survived to the first month of life--mostly those with pulmonary stenosis (PS, 99%), aortic stenosis (AS, 95%), ventricular septal defect (VSD, 92%), and atrioventricular septal defect (AVSD, 91%). Seventy-one percent of patients survived the first year of life--mostly those with PS (97%), AS (91%), atrial septal defect (ASD, 89%), VSD (80%), and persistent ductus arteriosus (PDA, 78%). In total, 67% of CHD patients can be expected to survive childhood. The highest survival rates were found in PS (94%), AS and ASD (84%), VSD and PDA (70-80%), and coarctation of the aorta (COA, 68%). The survival rate for the remaining forms of CHD was less than 50%. The highest mortality rate (10% of all children born with CHD) can be expected in the first postnatal week. The lowest survival in the first week was found among those with hypoplastic left heart (HLHS, 39%), double-outlet right ventricle (DORV, 50%), truncus arteriosus (TrA, 57%), pulmonary atresia (PA, 70%), and transposition of the great arteries (TGA, 83%). In addition, total anomalous pulmonary venous connection (TAPVC) and single ventricle had the highest risk of death in the first year of life.

Adolescent↗
PubMed1992

Lung function in atrial septal defect after heart surgery.

Lung volume, indices of lung elasticity and airway patency were measured in 74 patients, 9-21 yr old (15.0 +/- 2.5 yr) with atrial septal defect (secundum type) from 2-11 (5.1 +/- 2.5) yr after successful surgical correction. Clinical condition in all patients was classified as excellent. Heart surgery was performed at the age of 4-14.8 (9.9 +/- 3.0) yr. Lung function abnormalities were found in 35 (47.3%) patients. Lung recoil pressure was significantly increased in 24 (32.4%) patients. The mean value of lung recoil pressure at 100% of total lung capacity reached 123 +/- 31% of the predicted value (P < 0.0001). Specific static compliance was within normal limits. Specific airway conductance was significantly reduced in 13 (17.6%) patients. Maximum expiratory flow at 25% of vital capacity was significantly reduced in 4 (5.4%) patients. Static lung volumes did not differ from reference values. Since various abnormalities of lung function tests (most frequently the tests suggested increased lung stiffness and obstruction of larger airways) were revealed in almost half of the studied children and adolescents after successful surgery for atrial septal defect, we propose to carry out lung function tests routinely as another criterion of health conditions in these patients.

Adolescent↗
PubMed1992

Effect of prostaglandin E2 on the ductus arteriosus in the newborn rat. An ultrastructural study.

A patent ductus arteriosus (DA) was maintained in newborn rats (Wistar strain) by administering prostaglandin E2 (PG E2) in doses of 15 micrograms.kg-1 at 30 min intervals up to 300 min after birth. In the control animals, the DA was functionally closed 300 min after birth. The lumen was blocked by clustered endothelial cells at various stages of degeneration. Elastic membranes of the media had disintegrated into irregular fragments and the smooth muscle cells were contracted. Cytoplasm excrescences formed on their surface as a result of contraction protruded as hernias into adjacent muscle cells and into endothelial cells. The smooth muscle cells degenerated. The administration of PG E2 inhibited contraction of the smooth muscle cells and so also the development of degenerative changes; 300 min after birth the DA was fully patent, the elastic membranes were structurally intact, regularly organized and continuous. The smooth muscle cells had the character of synthesizing cells with richly developed granular endoplasmic reticulum. The intima and its endothelial lining were likewise free from structural changes. The ultrastructural image of the wall of the DA correspondent to the state 10 min after birth, when the DA was fully patent. The administration of PG E2 did not induce any ultrastructural changes indicative of injury to the wall of the DA.

Animals↗