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M Tichý

Publications and source records attributed to M Tichý.

At least 19 recordsLinked to original sources
PubMed2002

Recombination of D3+ ions in the afterglow of a He-Ar- D2 plasma.

We report measurements of the rate coefficient alpha for recombination of D3+ with electrons in a He-Ar-D2 plasma. The observed rate coefficient is dependent on the deuterium number density indicating that third-body assisted recombination is efficient and significantly contributes to recombination. When the deuterium number density is decreased to 7x10(10) cm(-3), the rate coefficient also decreases to alpha approximately 6x10(-9) cm3 x s(-1). These data indicate that the binary dissociative recombination of D3+ is very slow with alphaDR<6x10(-9) cm3 x s(-1). The observation of a deionization process proceeding via formation of D5+ is also reported.

Journal Article↗
PubMed2001

[Occurrence of celiac disease in siblings and offspring of patients with celiac disease].

BACKGROUND: Incidence of the coeliac disease in our population is 0.3 to 0.5%, however, in direct relatives of patients with coeliac disease incidence rises up to 5-15%. Though the disease in not always clinically manifested, it can be identified by serologic screening. METHODS AND RESULTS: 96 patients treated for active coeliac disease and their 130 siblings were examined. In four of 130 siblings the disease clinically manifested and was confirmed with finding of enteropathy of jejunal mucosa. In 14 out of 126 asymptomatic siblings endomysial antibodies were identified and in 11 of them enteropathy was diagnosed. Coeliac disease was diagnosed in 15 (11.5%) persons from 130 siblings. Also 74 offsprings of 43 parent patients were examined. In four of them the coeliac disease manifested clinically and was later confirmed with finding of enteropathy. Antiglidin antibodies were tested in 45 asymptomatic offsprings with 6 positive results. Endomysial antibodies were tested in 25 asymptomatic offsprings with one positive result. Villous atrophy of jejunal mucosa was found in four asymptomatic offsprings. Coeliac disease was diagnosed in 8 (11.5%) persons from 74 offsprings. CONCLUSIONS: Coeliac disease represent a major risk for the patient's direct relatives. Goal-directed examination and the early diagnosis of the disease in childhood may help to prevent impairments in the development of the child and possible complications later.

Adolescent↗
PubMed2001

Toxic effects of sarin in rats at three months following single or repeated low-level inhalation exposure.

Male albino Wistar rats were once or repeatedly exposed to three various low concentrations of sarin for 60 min. in the inhalation chamber. The clinical status of control as well as sarin-poisoned rats was tested 3 months after exposure to sarin using biochemical, haematological, neurophysiological, behavioural and immunotoxicological methods. While biochemical and haematological parameters, including the activities of cholinesterases in erythrocytes, plasma and various organs (brain, diaphragm), did not differ from the control values regardless of the sarin concentration used, few signs of sarin-induced neurotoxicity and immunotoxicity in sarin-poisoned rats were demonstrated. This was especially true when the single exposure of rats to non-convulsive symptomatic concentration and repeated exposure of rats to clinically asymptomatic concentration of sarin was used. In rats repeatedly poisoned with clinically asymptomatic concentrations of sarin, the alteration of the gait characterized by ataxia, the increase in the stereotyped behaviour, the increase in the excitability of the central nervous system following the administration of the convulsive drug pentamethylenetetrazol were observed. In rats poisoned with non-convulsive symptomatic concentration of sarin, the subtle supression of spontaneous, as well as lipopolysaccharides-stimulated, proliferation of spleen lymphocytes and the bactericidal activity of peritoneal macrophages was primarily observed besides the signs of neurotoxicity. Our findings confirm that both non-convulsive symptomatic and clinically asymptomatic concentrations of sarin can only cause very few, subtle long-term signs of neurotoxicity and immunotoxicity in sarin-poisoned rats when the rats were exposed to asymptomatic sarin concentrations repeatedly.

Administration, Inhalation↗
PubMed2001

Leucine and protein metabolism in rats with chronic renal insufficiency.

The aim of this study was to evaluate the effect of chronic uremia induced by 5/6 nephrectomy (5/6NX) on changes in protein and branched-chain amino acid (BCAA; valine, leucine and isoleucine) metabolism. The control group consisted of sham operated rats. Twenty eight weeks after surgery the parameters of protein and amino acid metabolism were evaluated using a primed constant intravenous infusion of L-[1-(14)C]leucine. A drop in BCAA levels and a significant increase in urea, creatinine and cholesterol were observed in plasma of all 5/6NX rats. However, severe uremia with acidosis developed only in one third of rats with 5/6NX. In 5/6NX rats with acidosis significant increases in proteolysis, leucine oxidation, leucine oxidized fraction, and leucine clearance were observed in comparison with the control group and rats with 5/6NX without acidosis. In addition, in 5/6NX rats with acidosis a significant decrease in valine concentration in gastrocnemius muscle was found. We conclude that marked activation of proteolysis occurs in severe chronic renal failure and is probably caused by metabolic changes related to acidosis development.

Acidosis↗
PubMed2001

[The founding and beginnings of the Institute of Physiology at the Medical School of Comenius University in Bratislava (1924-1939)].

The article deals with the history of foundation and beginnings of the Institute of Physiology of the Medical Faculty of Comenius University in Bratislava. In the school year 1924/25, after the Czechoslovak state university had been founded, the Physiological Institute began its work. The first director was prof. MUDr. Antonín Hanák. Under his leadership the basis of pedagogical and scientific activities in the Institute was established. In the school year 1926/27, Institute moved into the newly built rooms in Sasinková street No 2, where it has been located ever since. Professor Hanák had been working in Bratislava since 1924 till 1930. After his walk-off to Praha, professor MUDr. Vilém Hons became the head of the Institute. In the school year 1936/37 he was elected the dean of the Medical Faculty of Comenius University. He worked in Bratislava till 1939, when he was suspended from the service in the Slovak schools. Both Czech professors founded firm basis of physiology as a subject matter and as a scientific discipline in Slovakia.

Academies and Institutes↗
PubMed2001

The effect of trimetazidine on C-reactive protein, cytokines and adhesion molecules in the course of acute myocardial infarction.

The aim of this randomised, double-blind, placebo controlled, parallel group study was to assess the effect of trimetazidine (TMZ), a potent antiischaemic drug, on plasma C-reactive protein (C-RP), cytokine and adhesion molecule levels. The study population consists of 18 patients (16 males, 2 females, average age 56.45 +/- 10.97 years) with acute myocardial infarction admitted within 6 hours after onset of symptoms and treated with streptokinase. Blood samples were taken at 3-hour intervals during the time of treatment. All patients were randomised blindly using a centralised randomisation process, between trimetazidine (40 mg bolus i.v. then 60 mg per day for 48 hours intravenously in glucose infusion) or placebo group. Plasma C-RP level was significantly lower in TMZ group (39.5 mg/ml +/- 9.7 mg/ml) as compared to placebo (75.7 +/- 29.4 mg/ml, p < or = 0.001) and peaked 28 hours later in TMZ group. Plasma interleukin 6 (IL 6) level showed a sharp peak 9 hours after the onset of the symptoms in TMZ group (116.9 +/- 180.2 pg/ml vs. 45.4 +/- 37.9 pg/ml) and was increased up to 30 hours after the onset of the symptoms. Plasma interleukin 1 beta (IL 1 beta) was also higher in TMZ group notably 21 hours after the onset of symptoms (26.4 +/- 9.3 pg/ml vs. 16.2 +/- 2.4 pg/ml). TMZ group showed lower plasma E-selectin levels. Plasma IL 8, TNF alpha and ICAM 1 levels were without statistical significant differences. The present study demonstrates a significant reduction of plasma C-reactive protein level in the course of acute myocardial infarction treated with streptokinase and intravenous trimetazidine infusion compared with the group of patients without trimetazidine treatment.

C-Reactive Protein↗
PubMed2001

Inflammatory response to acute myocardial infarction complicated by cardiogenic shock.

We report a case of a 60-year-old man with acute myocardial infarction (AMI) treated using thrombolysis, and complicated by cardiogenic shock (CS). Plasma interleukin (IL) 1 beta, IL 6, IL 8, tumor necrosis factor alpha (TNF alpha), and soluble adhesion molecule (sICAM 1, sE-selectin) levels were measured at 3-h intervals. This observation showed the effect of AMI and CS on the plasma interleukin levels. Remarkable changes were found in the plasma TNF alpha level, which reached two significant peaks. The peak of the first elevation caused by AMI (80.11 pg/ml, vs. normal value 4.35 pg/ml, SD 21.3 pg/ml) was seen 6 h after the onset of the symptoms. After the period of significant decrease, TNF alpha level was increasing until the end of the observation period because of CS (the last TNF alpha level was 204.1 pg/ml). The plasma IL 1 beta level was continually increased during the period of observation (maximal IL 1 beta level 32.1 pg/ml, normal value < 10 pg/ml). The plasma IL 6 level reached the first peak caused by AMI nine hours after the onset of the symptoms (362.85 pg/ml, normal value (10 pg/ml). Because of CS, after the short period of decrease, the plasma IL 6 level was increasing until the end of the observation period (the last IL 6 level was 859.61 pg/ml). The plasma IL 8 level was also elevated throughout the time of observation (max. value 1652 pg/ml, vs. normal value < 30 pg/ml). The soluble adhesion molecule levels (sE-selectin and sICAM 1) were elevated throughout the period of observation without any significant peak.

Cell Adhesion Molecules↗
PubMed2000

Effect of hyperammonemia on leucine and protein metabolism in rats.

The cause of muscle wasting and decreased plasma levels of branched chain amino acids (BCAA), valine, leucine, and isoleucine in liver cirrhosis is obscure. Here we have evaluated the effect of hyperammonemia. Rats were infused with either an ammonium acetate/bicarbonate mixture, a sodium acetate/bicarbonate mixture, or saline for 320 minutes. The parameters of leucine and protein metabolism were evaluated in the whole body and in several tissues using a primed constant intravenous infusion of L-[1-14C]leucine. Ammonium infusion caused an increase in ammonia and glutamine levels in plasma, a decrease in BCAA and alanine in plasma and skeletal muscle, a significant decrease in whole-body proteolysis and protein synthesis, and an increase in leucine oxidized fraction. A significant decrease in protein synthesis after ammonium infusion was observed in skeletal muscle while a nonsignificant effect was observed in liver, gut, heart, spleen, and kidneys. We conclude that the decrease in plasma BCAA after ammonia infusion is associated with decreased proteolysis and increased leucine oxidized fraction.

Amino Acids, Branched-Chain↗
PubMed2000

Causes and treatment of residual urine volume after orthotopic bladder replacement in women.

OBJECTIVES: Intact innervation of the female urethra is conditional for normal urination. In the past, urethrectomy was performed as part of cystectomy. After intense anatomical studies of the female pelvis, urethral-function-sparing cystectomy was developed. METHODS: Our clinical group consists of 41 female patients who were operated from 1993 to 1998 for bladder cancer, utilizing cystectomy with orthotopic bladder replacement. RESULTS: In 28 patients, complete daytime continence was restored and in 13 patients, daytime continence was socially satisfactory (1-2 pads were used due to mild stress incontinence). The drawback of orthotopic replacements in females is the frequent development of serious residual volume, which was seen in one third of the 41 patients. The functional results of orthotopic neobladders and therapy of residual urine volume were documented using urodynamic studies. CONCLUSIONS: Postvoiding residual volume may be caused by isolated dysfunction of the urethra and can be treated with clean intermittent self-catheterization or with alpha-blockers, which improve evacuation of the neobladder.

Adult↗
PubMed2000

Gene aberrations in childhood brain tumors.

We present the results of the examination of prognostic markers in 40 children suffering from brain tumors. Prognostic markers such as amplification of the N-myc and c-myc, deletion of the 17p, and DNA ploidy are indispensable factors for the determination of diagnosis. An increased number of c-myc gene copies was found in malignant brain tumors, especially embryonal, more often than reported in the literature. N-myc amplification occurs in our group seldom, but it seems to be a sign of worse prognosis in glial and embryonal brain tumors. DNA aneuploidy was not found very frequently, but in high-grade tumors only.

Adolescent↗
PubMed2000

Electrophoretic characterization of a gamma-1-heavy chain disease.

This report describes a new case of gamma-1-heavy chain disease found in a woman with malignant lymphoproliferative disease. The patient's serum and urine containing gamma-1-heavy chains were analyzed using different electrophoretic approaches, especially two-dimensional electrophoresis and immunoblotting analysis. In a serum sample, five sets of gamma-1-heavy chain spots differing in molecular weight with acidic pI values and one set of more basic gamma-1-heavy chain spots were found. The major group of spots exhibited molecular weight in the range from 29 to 39 kDa. Examination of urine sample proved the presence of the more basic set of gamma-1-heavy chain spots and two acidic groups, including 29 to 39 kDa set.

Aged↗
PubMed2000

Expression of Bcl-2 in dysplastic and neoplastic cervical lesions in relation to cell proliferation and HPV infection.

Expression of the bcl-2 gene has been shown to effectively confer resistance to programmed cell death in a variety of tumors. The bcl-2 proto-oncogene is involved in the development of human follicular lymphomas and also in a number of solid tumors such as carcinomas of prostate, breast, lung and GIT. The present study was designed to analyze the role of Bcl-2 expression in cervical intraepithelial squamous neoplasias (CIN) and cervical invasive carcinomas. Special attention was given to the association of Bcl-2 expression with the grade of the lesion, proliferative activity (expression of nuclear antigen of proliferative cells - PCNA) and human papillomavirus (HPV) DNA positivity. We examined tissue samples obtained from 86 women with varying degrees of cervical disease. Bcl-2 and PCNA were investigated using immunohistochemical staining and detection of HPV DNA was performed by hybridization in situ. Increased Bcl-2 expression was observed in advanced degrees of dysplasia and in carcinomas. We found a strong association between the presence of Bcl-2 in pathological epithelium with both the degree of dysplasia and the proliferative activity. We also observed a significant correlation between the amount of Bcl-2 positive lymphocytes infiltrating the lesions and the degree of disease. We, therefore, suggest that Bcl-2 expression in these lymphocytes may influence the antiviral or antitumor immune response. On the other hand we did not detect any significant correlation between the Bcl-2 oncoprotein and the presence of HPV. These results indicate that Bcl-2 may play an important role in the development of cervical cancer.

Adolescent↗
PubMed2000

Leucine and protein metabolism after bilateral nephrectomy in rats: the role of hepatic tissue.

The aim of this study was to evaluate the effect of acute uremia on changes in leucine and protein metabolism in the whole body and in hepatic tissue. Acute renal insufficiency was induced by bilateral nephrectomy (BNX). Twenty-four hours later, parameters of protein and amino acid metabolism were evaluated in the whole body using primed constant intravenous infusion of L-[1-14C]leucine, and in isolated perfused liver (IPL) using cx-keto[1-14C]isocaproate. The control group consisted of sham-operated rats. BNX induced a marked decrease in proteolysis, protein synthesis, leucine oxidized fraction and leucine clearance. The decrease in protein synthesis was higher than in proteolysis. A significant drop in protein synthesis was observed in muscle, gut, heart and spleen. The study with IPL in BNX animals showed decreased oxidation of ketoisocaproic acid and higher concentrations of the branched-chain amino acids (BCAA) leucine, isoleucine and valine in perfusion solution. We conclude that the cause of rapid depletion of body proteins after BNX is a greater decrease in protein synthesis than in proteolysis associated with an increase in leucine oxidized fraction. The data obtained in the IPL model indicate that BNX causes metabolic changes that enable resynthesis of BCAA from corresponding branched-chain keto acids in liver.

Acute Disease↗
PubMed1999

Comparison of MR spectroscopy and MR imaging with contrast agent in children with cerebral astrocytomas.

We studied 33 patients with astrocytomas of different grades (68 examinations) by magnetic resonance imaging (MRI) and proton MR spectroscopy ((1)H-MRS). We found that in 80% of the spectra, the presence of signals in the area of 0.8-1.5 ppm, assigned to lipids/lactate in (1)H-MR spectra, correlated with signal enhancement after Gd-DTPA administration. We suggest that visibility of lipid/lactate signals could be due to blood-brain barrier damage, which is characterized by contrast agent enhancement.

Adolescent↗
PubMed1999

Cytokines and adhesion molecules in the course of acute myocardial infarction.

The plasma levels of interleukin 1 beta (IL 1beta), interleukin 6 (IL 6), interleukin 8 (IL 8), tumor necrosis factor alpha (TNF-alpha), E-selectin, ICAM 1 and C-reactive protein (CRP) have been studied in 24 patients with acute myocardial infarction in the course of 96 h. The plasma IL 1beta and IL 6 levels were continually elevated during the 96 h study period (the peak of plasma IL 1beta level was 22.2 pg/ml, S.D. 8.6, P < 0.001, normal values of IL 1beta are less than 10 pg/ml, the mean peak plasma concentration of IL 6 was 184.9 pg/ml, S.D. 134.7, vs. normal values of 15.57 pg/ml, S.D. 2.4, P < 0.001). The mean plasma IL 8 level was increased for the duration of the study, the mean plasma IL 8 level was 103.0 pg/ml, S.D. 23.4 (normal value was below 30 pg/l, S.D. 8.0) P < 0.001. The plasma TNF-alpha level was elevated throughout the time of observation without any significant peak. The mean plasma TNF-alpha concentration was 46.8 pg/ml, S.D. 2.13, vs. normal value 4.35 pg/ml, S.D. 1.23, P < 0.001. The plasma E-selectin level reached the mean level of 145.1 ng/ml, S.D. 75.4, vs. normal value 29.1-63.4 ng/ml, P < 0.001 at an interval of 15-42 h after the onset of the symptoms. The plasma ICAM 1 level showed only a slight significant increase during the first 36 h. The plasma CRP concentration increased later than IL 6, and reached a peak at 42 h after the onset of the symptoms (69.2 mg/l, S.D. 29.9, vs. 1.2 mg/l, S.D. 4.7, P < 0.0001). We conclude that cytokines and adhesion molecules can play an important role in the mechanisms of tissue injury in the process of ischemia and reperfusion.

Adult↗
PubMed1999

Effect of ethanol on the urinary excretion of cyclohexanol and cyclohexanediols, biomarkers of the exposure to cyclohexanone, cyclohexane and cyclohexanol in humans.

OBJECTIVES: This study explored the acute effect of ethanol (EtOH) on the urinary excretion of cyclohexanol (CH-ol), 1,2- and 1,4-cyclohexanediol (CH-diol), biomarkers of exposure to important solvents, and chemical intermediates cyclohexanone (CH-one), cyclohexane (CH) and cyclohexanol. METHODS: Volunteers (5-8 in each group) were exposed for 8 hours either to CH-one, CH or CH-ol vapor at concentrations of about 200, 1000, and 200 mg/m3, respectively, with concomitant ingestion of EtOH (4 14-g doses taken during the exposure). Urine was collected for 72 hours and analyzed for CH-ol and CH-diols using a procedure involving acidic hydrolysis and gas chromatographic determination. RESULTS: The metabolic yields of CH-ol, 1,2-, and 1,4-CH-diol, respectively, in the exposures with EtOH were as follows: 11.3%, 36%, 23% after the exposure to CH-one, 3.1%, 15%, 8% after the exposure to CH, and 6.6%, 24%, 18% after the exposure to CH-ol. [The corresponding values obtained previously in matching experiments without EtOH were as follows: 1.0%, 39%, 18% (CH-one); 0.5%, 23%, 11% (CH); and 1.1%, 19%, 8% (CH-ol).] The excretion curves of the metabolites in the exposures with EtOH were not delayed when compared with the corresponding curves of a comparison group. CONCLUSIONS: The urinary excretion of CH-diols is much less sensitive to EtOH than that of CH-ol. It is recommended to employ CH-diols as useful and more reliable biomarkers of exposure to CH-one, CH and CH-ol in field examinations.

Adult↗
PubMed1999

[Mantle cell lymphoma as a diagnostic and therapeutic problem].

The authors present the characteristics of a group of 23 patients with mantle cell lymphoma. In the group only a slight predominance of men over women was found (1.1:1), the median age was 63 years. Twenty-one (91%) of the patients were diagnosed in stage IV (Ann Arbor). In all these patients the bone marrow was affected. In 19 of them immunoflowcytometric analysis revealed the typical clone of B lymphocytes (CD5 positive)/CD 23 negative). The majority of patients had at the time of diagnosis a large tumourous mass with massive splenomegaly (61%), hepatomegaly (57%) and bulky disease (52%). The node was excised in 17 patients, but in four patients (24%) during the first session the diagnosis was not assessed correctly. In the laboratory findings an inclination to anaemia, thrombocytopenia, lymphocytosis and in particular to high levels of serological indicators of activity of the disease dominated--lactate dehydrogenase, beta-2-microglobulin and serum thymidine kinase. All patients were treated by chemotherapy. Complete remission was achieved by the date of evaluation in one patient (4%), partial remission in seven patients (30%) but 48% patients did not respond to first line treatment. Nine patients of the group died, their median of survival was 14 months (0-24), the median of the follow up of the remaining patients was 133 months (2-31). Two female patients had large-dose treatment with subsequent administration of autologous stem cells. The first one is after 370 days of treatment in complete remission, the second one developed a relapse 100 days after the procedure. From the results and analysis of the literature ensues that mantle cell lymphoma is one of the aggressive malignant B-lymphoproliferations with a very adverse prognosis and it deserves therefore special diagnostic and intense therapeutic attention.

Adult↗