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V Palicka

Publications and source records attributed to V Palicka.

At least 19 recordsLinked to original sources

Colon submucosal microdialysis: a novel in vivo approach in barrier function assessment - a pilot study in rats.

During shock, prognosis of a patient depends largely on intestinal barrier function. The potency of gut epithelium to represent an obstacle to toxins is determined by the blood supply. All established methods of mucosal function determination necessitate the functional involvement of bloodstream. Microdialysis allows monitoring of extracellular substances in the gut submucosa, but its potential use for gut barrier integrity assessment is unknown. Twelve rats underwent perfusion of the descending colon either with 20 % ethanol or control medium (vehicle). Both media contained equal amounts of a radioactive tracer substance ((51)Cr-EDTA). Mucosal permeability for (51)Cr-EDTA was assessed by microdialysate to luminal perfusate activity ratios. Sampling was performed using the colon submucosal microdialysis technique. The group subjected to ethanol treatment had profound macro- and microscopical alterations in perfused colonic segment associated with a significant increase in tracer permeability during ethanol exposure (2.354+/-0.298 % for ethanol as opposed to 0.209+/-0.102 % for control group, p 0.01), which remained elevated for 60 min after cessation of ethanol administration (3.352+/-0.188 % for ethanol compared to 0.140+/-0.0838 % for the control group, p 0.001). Submucosal microdialysis with radioactive tracer substance can be considered a feasible and advantageous alternative of gut barrier function estimation. Parallel monitoring of local tissue chemistry with this method remains a challenge in the future.

Animals↗

Differential effects of statins and alendronate on cholinesterases in serum and brain of rats.

Acetylcholinesterase (AChE) inhibitors represent standard treatment of Alzheimer's disease. Cholesterol plays an important role in Alzheimer's disease development. Because cholesterol synthesis may be inhibited by statins or bisphosphonates, we hypothesized that these drugs might possibly have an influence on cholinesterases. Moreover, we also evaluated if the cholesterol-lowering agents that cross the blood-brain barrier (e.g. simvastatin) should be more effective than those which do not (e.g. atorvastatin). Four groups of rats were orally administered simvastatin, atorvastatin, alendronate or vehicle for seven days. Thereafter, blood samples were taken and the basal ganglia, septum, frontal cortex, and hippocampus were isolated from brains for measurement of acetylcholinesterase activity. In the blood, activities of neither acetyl- nor butyrylcholinesterase were influenced by any of the applied drugs. In the brain, no significant changes in AChE activity were observed after administration of atorvastatin. Both simvastatin and alendronate significantly suppressed the activity of AChE in the frontal cortex. In conclusion, our results confirmed the hypothesis that cholesterol-modifying drugs modulate AChE activity and it is more reasonable to use a blood-brain barrier penetrating drug.

Alendronate↗

International Staging System required standardization of biochemical laboratory testing in multiple myeloma.

The standardization of biochemical measurement procedures in multiple myeloma is necessary for reliable prognostic stratification of patients in multicentric trials. The new prognostic index International Staging System for multiple myeloma uses only two laboratory markers, albumin and beta-2 microglobulin. Our study compared results of albumin, beta-2 microglobulin and monoclonal immunoglobulin measurements from six centers which provide treatment for multiple myeloma in the Czech Republic and attempted to standardize the analytic procedures. We have found that the measurement of albumin is well standardized and the results from all laboratories were comparable. The measurement of beta-2 microglobulin achieved comparability only after a partial unification of analytical methods. The determination of monoclonal immunoglobulin concentration provided comparable results for concentrations higher than 20 g/l with higher variability for lower values.

Antibodies, Monoclonal↗

Evaluation of in vitro effects of natural substances of plant origin using a model of protein glycoxidation.

In an in vitro model with purified porcine aspartate aminotransferase (AST, EC 2.6.1.1) as the protein, the effects of phenolic antioxidants of plant origin (arbutin, methylarbutin, ferulic and isoferulic acids, o-coumaric and p-coumaric acids, quinic acid), flavonoids (baicalin and baicalein), and of hydroxycitric acid (HCA) at 0.5-50 mM concentration on the enzyme activities and on its glycation by 50 mM D-fructose as the glycating agent were studied. During incubation with AST at 37 degrees C up to 24 days, fructose alone decreased AST activities as a result of protein glycation. In the absence of fructose, 50 mM phenolic compounds gradually decreased AST activity, while no or a weak effect of individual compounds was found at 3 mM concentration. A direct negative effect on AST was pronounced with ferulic acid. On the other hand, beneficial influences of phenolic compounds on glycation of AST by fructose were found mostly at 3 mM concentration. Effects on glycation were vague at 50 mM concentration, probably due to a combination of direct negative influences and antiglycation effects of individual compounds. No effect, neither positive nor negative, on AST activity and protein glycation, was found with quinic acid. The flavonoid baicalin and its aglycon baicalein rapidly decreased the in vitro activity of the enzyme in all concentrations used (0.5-3 mM), and no beneficial effects of the compounds on glycation of the enzyme by fructose were found. The influence of HCA on glycation was concentration-depended, ranging from beneficial inhibition of glycation at 2.5 mM concentration to a strong decrease in AST activity at 10 mM HCA. Both the beneficial and undesirable effects of natural antioxidants should be considered in case they are used as antiglycation factors. The results obtained can contribute to the evaluation of quality of various generally recommended antioxidants.

Animals↗

Comparison of different protocols for 13C-urea breath test for the diagnosis of Helicobacter pylori infection in healthy volunteers.

OBJECTIVE: The (13)C-urea breath test ((13)C-UBT) is the most accurate non-invasive method for diagnosis of Helicobacter pylori infection. However, several methodological issues have not been resolved yet. The aim of this study was to test different protocols of (13)C-UBT to find the optimal test drink and sampling interval. MATERIAL AND METHODS: (13)C-UBT was performed at 3-day intervals in 27 healthy volunteers using citric acid (test A), orange juice (B) and still water (C) as test drinks. Breath samples were collected from time 5 to 60 min. A total number of 2106 breath samples were analysed by isotope ratio mass spectrometry (cut-off value 3.5). RESULTS: Differences in delta values were greater than would be expected by chance (A versus B and A versus C at times 20, 25, 30, 35 and 40 min, p<0.05, Dunnett's method). There were no grey zone- or false-negative results among H. pylori-positive persons in test A at any time, but some were found in tests B and C. Optimal intervals for breath sampling are at times 20 or 25 min after (13)C-urea ingestion. CONCLUSIONS: Citric acid solution as a test drink and 20- or 25-min breath sampling intervals are optimal for the (13)C-UBT in healthy volunteers.

Adult↗

[Shared pathogenesis of infectious and cardiovascular diseases--year 2005's view].

Entry of microorganisms into the blood stream provokes a decline in the contractile function of the cardiac muscle. Lipopolysaccharide of Gram-negative bacteria sets off production of pro-inflammatory cytokines including bactericidal concentrations of nitric oxide which set up the first defence line against bacteremia. At the same time, however, the performance of the cardiovascular system is negatively affected. The immediate menace resides in the occurrence of septic shock, while chronic infectious diseases that are accompanied by low-grade inflammation have been suspected to take an active part in the initiation and progression of atherosclerosis. This hypothesis, as attractive as it may appear, has not yet been accepted unequivocally. The article offers an up-to-date review of the signalling cascades which permit activation by lipopolysaccharide of the target cells. The same holds true for cellular activation by non-infectious stimuli. An emerging paradigm seems plausible that the same biologic events which serve to combat acute infection might be in the long run involved in the pathogenesis of atherosclerosis.

Atherosclerosis↗

[Examination of gastric emptying rate by means of 13C-octanoic acid breath test. Methods of the test for adults and results of the investigation of healthy volunteers].

BACKGROUND: 13C-octanoic acid breath test (13C-OABT) is a simple, safe and non-invasive technique for measuring gastric emptying. However, the method has not been standardized yet. Aim of the study was to work up, introduce and evaluate our own method of the 13C-OABT for adults. METHODS AND RESULTS: Ten healthy volunteers entered the study (5 men, 5 women, mean age 32 years, 50 % Helicobacter pylori positive). Standard test meals (with 100 mg 13C-sodium octanoate) were used three times within 3 weeks. The same solid meal (1,178 kJ) for Tests 1 and 2 contained scrambled egg (+ 3 g oil), white bread (40 g), butter (10 g) and distilled water (200 ml). Semi-solid meal (1,020 kJ) for Test 3 contained milk pudding (200 g) and distilled water (200 ml). Duplicate breath samples were obtained before and every 15 minutes after eating the test meal during 255 minutes. Altogether 1,080 breath samples were analysed twice (isotope ratio mass spectrometry, AP2003 Analytical Precision, UK). To assess the half-life of elimination (t1/2 E), we modelled the process of elimination with the incomplete gamma-function, which has a convenient form for the empiric plotting of breath test data. Mean t1/2E was 136+/-10 minutes (Test 1), 134+/-14 (Test 2) and 123+/-16 minutes (Test 3). Clinical reproducibility of 13C-OABT in particular persons was 98.2% (18 breath samples series), 90.8 % (15 samples) and 87.1% (9 breath samples series). There was a significant correlation between Test 1 and Test 2 results (r=0.887, p<0.0001). Mean difference of duplicate breath sample analysis was 1.460 % (in 540 pairs), mean baseline one-day analysis difference was 0.0982 (99.9274% accuracy). In healthy volunteers, normal range of t1/2E is 110-160 minutes for solids and 91-155 minutes for semisolid test meal. Using our own computed mean time of intermediate metabolism of 13C-octanoic acid (76.5+/-7.5 minutes), gastric emptying half-time is 33.5-83.5 minutes for solids and 14.5-78.5 minutes for semisolid test meal in healthy volunteers. CONCLUSIONS: The 13C-OABT is accurate non-invasive method for gastric emptying measurement.

Adult↗

Changes in metabolism and blood flow in peripheral tissue (skeletal muscle) during cardiac surgery with cardiopulmonary bypass: the biochemical microdialysis study.

The aim of this study was to monitor the metabolism and blood flow in the interstitium of the skeletal muscle during cardiac surgery with cardiopulmonary bypass (CPB) and in the early postoperative period by means of microdialysis and to compare metabolic changes during CPB at normothermia (NT) and hypothermia (HT). Surgical revascularization using CPB was performed in 50 patients, 25 patients (group HT) were operated using hypothermic CPB, 25 (group NT) using normothermic CPB. Interstitial microdialysis was performed by two CMA 60 probes (CMA Microdialysis AB, Solna, Sweden) inserted into the patient's deltoid muscle. Constituents analysed in the obtained dialysates, collected at intervals, were glucose, urea, glycerol and lactate. Tissue blood flow was monitored by dynamic microdialysis with gentamicin as a marker. In both groups, NT versus HT, similar dynamics of concentrations were found. Low initial concentrations were followed by gradual increases during CPB and in the following phase of the operation. Concentrations were higher in the NT group. Immediately after the operation, the decrease in values continued, with a gradual increase in the succeeding postoperative period in both groups. Similar dynamic changes in the lactate concentration were found in both groups. The gentamicin concentrations were lower in the NT group (versus the HT group). The results showed dynamic changes in the interstitial concentrations of glucose, urea, glycerol and lactate, which depend on the phase of the surgery in the CPB and early postoperative phase in the both groups of patients. Higher tissue perfusion of the skeletal muscle was noted in those patients operated on in normothermia. The dynamics of the concentration changes of these substances in the interstitium of the skeletal muscle has been proven to be caused by both the metabolic activity of the tissue and by the blood flow through the interstitium of the muscle.

Aged↗

[Monoclonal gammopathies in a series of 1683 plasma donors].

BACKGROUND: Monoclonal gammopathies are very heterogenic groups of disorders characterized by the proliferation of a single clone of plasma cells producing a monoclonal immunoglobulin (paraprotein). Monoclonal gammopathies (Kyle) are classified as malignant monoclonal gammopathies and monoclonal gammopathy of the undetermined significance. The prevalence of paraproteinemias is about 1% in people up to the age of 60 and about 10% in persons older than 80 years of age. METHODS AND RESULTS: We examined blood serum from 1683 plasma donors (18-60 years) by electrophoretic analysis during the period 1999-2003. We determined monoclonal immunoglobulins in 10 of them (0.6%). The presence of monoclonal gammopathies of undetermined significance was the most frequent (6x), one case was a transient monoclonal gammopathy, two patients were not examined and one patient (46 years old man) had the diagnosis of multiple myeloma. The immunoglobulin class of six paraproteins IgG were observed (4x kappa, 2x lambda), paraprotein IgA was found in two patients (1x kappa, 1x lambda), paraproteinemia IgM-kappa in one patient and double paraproteinemia IgG-kappa + IgA-kappa was proved in another one. M-gradient was determined in nine cases by screening electrophoretic analysis on the agarose gel (SEBIA, France). One M-protein (IgA-lambda) was hidden in beta-globulin region and the diagnosis of multiple myeloma was determined after clinical manifestation this disease. CONCLUSIONS: Our study shows, that electrophoretic analysis of serum is necessary to do in all types of blood donors (plasma, blood, thrombocytes). Reliable proof of monoclonal immunoglobulins in blood serum or urine is given only by immunofixation electrophoresis.

Adolescent↗

[Characteristics of patients with osteopenia treated with glucocorticoids at the Osteoporosis Clinic of the Medical Faculty Hospital in Hradec Kralove].

One-hundred-ninety-seven osteopenic or osteoporotic patients registered at the University hospital osteology outpatient clinic during 1995-1999 and exposed to glucocorticoids were included in the cohort. Prevalence of glucocorticoid treatment (of all patients) was 12.4%. The patients diagnosed with rheumatoid arthritis showed the greatest reduction in bone density (average T-score = -2.70), fractures were most frequently recorded in patients suffering from asthma or lupus erythematodes.

Adolescent↗

[Interstitial microdialysis study of changes in metabolism and blood flow in skeletal muscles during cardiac surgery with normothermic and hypothermic extracorporeal circulation].

AIM: Hypoperfusion of peripheral tissues and splanchnic organs during cardiac surgery in extracorporeal circulation may lead to the origin of serious complications. The aim of the study was to monitor metabolism and blood pressure in interstital peripheral tissue, skeletal muscle, during the operation on the patient with extracorporeal circulation (ECC) in an early post-operation period by means of microdialysis. METHODS: The interstitial microdialysis is a minimally invasive method for the biochemical monitoring of metabolic changes and blood pressure in extracellular space of tissue. The substances in interstitium pass across a semipermeable membrane of the inserted microdialysis probe and may be analyzed. Microdialysis in this study was performed by means of two microdialysis probes CMA (CMA Microdialysis AB, Sweden) inserted into the deltoid muscle of the surgically treated patient. The probes were perfused by the Ringer solution at the rate of 0.3 ml/hour. The dialysates were sampled in the following intervals: beginning of the operation, beginning of ECC, end of ECC, end of the operation, two hours during the post-operation period. Standard biochemical methods were to evaluate, in the dialysates, glucose, urea, glycerol and lactate. The blood flow in the interstitium was monitored by means of dynamic microdialysis of gentamycine as a marker. Microdialysis was performed in 40 patients with ischemic heart disease, operated on in the extracorporeal circulation. In 20 patients the ECC was performed in normothermia (NT), while in the other 20 patients it was made in hypothermia (HT). RESULTS: In both groups, NT versus HT, a similar dynamism of interstitial concentration of the observed substances in relation to the operation phase and in early post-operation period. Low initial concentrations were gradually increasing during the extracorporeal circulation and increased further after the end of extracorporeal circulation and also in the subsequent phase of the operation. The concentration values of the analytes under observation were higher in the groups operated on under normothermia, apparently due to normal cellular activity during normothermia (versus values in hypothermia). Immediately after the operation the observed values decreased in the both groups and subsequently gradually increased in the post-operation period in the both groups. The trend of dynamic changes of the observed analytes, selected as compounds indicating metabolic activity of skeletal muscles during hypothermia documents a lower metabolic activity of the cells during hypothermia and its marked increase (against NT) in the phase of subsequent normalization of the tissue temperature. Analysis of the concentrations of lactate, as a compounds mapping anaerobic metabolism of skeletal muscle, revealed similar dynamic changes in the both groups (NT vs. HT). There were no significant differences, related to the phase of the operation or the phase of immediate post-operation course when the both groups were compared. The analysis of gentamycine concentrations as a flow marker revealed lower gentamycine concentrations in dialysate during the operation, ECC and the early post-operation course in the group operated on in normotheramia (vs. HT), indicating a higher tissue flow in skeletal muscle against the group of patients operated on under hypothermia. CONCLUSION: The results of the microdialysis study demonstrated dynamic changes in interstitial concentrations of the observed compounds (glucose, urea, glycerol and lactate) related to the phase of operation on the heart in extracorporeal circulation and in early post-operation period. A higher perfusion of skeletal muscle was documented in patients operated on under normothermia. It became obvious that the dynamism in the changes of the compounds observed in the interstitium of skeletal muscle was determined by metabolic activity of the tissue as well as by blood flow in the muscle interstitium.

Aged↗

Influence of P-glycoprotein on the transplacental passage of cyclosporine.

The transfer kinetics of cyclosporine across the dually perfused rat placenta in the maternal to fetal direction and a possible involvement of P-glycoprotein were investigated. The transplacental clearance of cyclosporine in the materno-fetal direction was found to be dependent on the maternal inflow concentration of cyclosporine. Coadministration of cyclosporine with an excess of quinidine or chlorpromazine into the maternal compartment revealed 1.7- and 1.9-fold increase in cyclosporine concentration in the fetal compartment. In the experiments where quinidine was present both in the maternal and fetal compartments, cyclosporine appeared in the fetal compartment significantly faster, and its amount was three times higher when compared with controls. Conversely, quinidine or chlorpromazine did not affect the transplacental passage of L-[(3)H]-glucose. The interference of quinidine with the metabolism of cyclosporine in the placenta was excluded because only traces of M-1 and M-17 metabolites were found in the fetal solutions. Sodium azide, a mitochondrial respiratory inhibitor, was found to double the rate of cyclosporine, but not L-[(3)H]-glucose, passage across the placenta. Our findings indicate that P-glycoprotein pumps cyclosporine out of the trophoblast cells of the rat placenta in the ATP-dependent manner and restricts the passage of cyclosporine across the placental barrier.

ATP Binding Cassette Transporter, Subfamily B, Mem↗

Biochemical profile and survival in nonagenarians.

OBJECTIVES: Old age is associated with an increase in frequency of disorders involving virtually all organ systems, resulting in a rise of mortality. The aim of the project was to study the relationship between biochemical markers and all-cause mortality in a defined age group. DESIGN AND METHODS: Thirty-eight nonagenarians, aged 92 +/- 2 (range 90-100) years entered the study. At the start of the study, a sample of peripheral blood and urine were obtained for analysis of 50 basic biochemical, hematologic and biologic parameters. The assessment was then repeated in 6 to 12 months intervals. The significance of difference between surviving subjects and those who died was examined by Mann-Whitney U test and the correlation between the variables was studied by Spearman rank correlation coefficient. RESULTS: During the observation period, 21 of the studied subjects died leaving 17 persons still alive at the end of the study. The mean time from the first measurement to the death was 12 +/- 10 (range 0-33) months. The mean follow-up time in surviving subjects was 31 +/- 12 (range 4-45) months. Serum vitamin E and calcium were significantly higher, and serum alanine aminotransferase (ALT) and urinary neopterin were significantly lower in survivors compared to the subjects who died. No other parameters were significantly different in survivors and in persons who died. Urinary neopterin exhibited a significant negative correlation with serum sodium concentration (RS = -0.50, p < 0.01), but the other parameters did not correlate significantly. CONCLUSION: In conclusion, among the parameters studied, differences between survivors and nonsurvivors were observed only for serum vitamin E, calcium, ALT and urinary neopterin. These findings may form a basis for prospective interventional trials in this group of patients.

Aged↗

Inhibitory effect of glycation on catalytic activity of alanine aminotransferase.

Non-enzymatic glycation is a common post-translational modification of tissue and plasma proteins which can impair their functions in living organisms. In this study, the authors have demonstrated for the first time an inhibitory effect of in vitro glycation on the catalytic activity of alanine aminotransferase (ALT, EC 2.6.1.2), a pyridoxal phosphate enzyme with several lysine residues in the molecule. The porcine heart enzyme was incubated with 50 mmol/l D-fructose, D-glucose, D,L-glyceraldehyde, or D-ribose in 0.1 mol/l phosphate buffer (pH 7.4) at 25 degrees C for up to 20 days. The strongest glycation effect was shown by D,L-glyceraldehyde, which caused complete enzyme inhibition within 6 days. After 20 days of incubation, the ALT activity in samples with D-fructose and D-ribose was less than 7% of the initial enzyme activity. A statistically significant effect of D-glucose on the enzymatic activity of ALT was not found. Incubation of ALT with D-fructose, D,L-glyceraldehyde and D-ribose minimized its catalytic activity both in the glycated and non-glycated fractions of the samples. Markedly higher activity was found in the glycated fraction with glucose. The inhibitory effect of glycation of ALT with D-fructose and D-ribose was found to be more intensive in the presence of L-alanine and weaker in the presence of 2-oxoglutarate. The findings suggest that glycation of the epsilon-amino group of Lys313 as a crucial part of the catalytic site of ALT may contribute to ALT inactivation in the presence of glycating sugars. Nevertheless, glycation of lysine residues outside the active center of ALT seems to be primary.

Alanine↗

Comparison of different immunoassays for CA 19-9.

We compared six routinely employed immunoassay kits: Architect i2000 and AxSYM, Abbott Laboratories; Elecsys 2010, Roche Diagnostics; ELSA, CIS-BioInternational; Immulite 1, Diagnostic Products Corporation; and IRMA-mat, Byk-Sangtec Diagnostica. Using all analytical systems, we measured identical groups of clinical samples completed with selected control samples. The repeatability of measurements (coefficient of variation) ranged from 2.1% (Elecsys 2010) to 6.7% (ELSA). The parameters of Passing-Bablok regression show significant systematic differences among analytical systems. Data from a Bland-Altman diagram suggest that these differences project onto other, still more significant individual differences among individual samples. Though the cut-off values differ between various systems, no similar clinical efficacy appears to be attained. The behavior of individual systems is quite different for identical control materials and does not necessarily duplicate the calibration for biological samples. The results of determining CA 19-9 cannot be extrapolated from one analytical technique to another, even in cases where the same monoclonal antibody is used. Standardization of CA 19-9 measurement systems is necessary to allow use of the results for the purposes of evidence-based medicine.

CA-19-9 Antigen↗