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J Borovicka

Publications and source records attributed to J Borovicka.

At least 19 recordsLinked to original sources
PubMed2006

[Helicobacter pylori 2006: how to test, when to treat].

The role of Helicobacter pylori in peptic-disease, gastric adeno-carcinoma and the MALT- lymphoma is established. The H. pylori diagnostics and the eradication therapy are highly disputed in patients with dyspepsia. An endoscopy is recommended to patients older than 45 who have dyspeptic disorders. Non-invasive testing and treatment is an adequate option to those patients younger than 45, if no alarm symptoms exist. The H.pylori serology, the 13C- breath test and the stool-antigen test have proven to be the best in laboratory testing. The therapeutic regimen of H. pylori eradication consists of a proton pump inhibitor (PPI) and two antibiotics, though it isn't always successful. After a second treatment failure, a H. pylori culture is indicated to asses the antibiotic resistances.

Adenocarcinoma↗
PubMed2006

Autofluorescence endoscopy in surveillance of Barrett's esophagus: a multicenter randomized trial on diagnostic efficacy.

BACKGROUND AND STUDY AIMS: The reference surveillance method in patients with Barrett's esophagus is careful endoscopic observation, with targeted as well as random four-quadrant biopsies. Autofluorescence endoscopy (AFE) may make it easier to locate neoplasia. The aim of this study was to elucidate the diagnostic accuracy of surveillance with AFE-guided plus four-quadrant biopsies in comparison with the conventional approach. PATIENTS AND METHODS: A total of 187 of 200 consecutive Barrett's esophagus patients who were initially enrolled (73 % male, mean age 67 years, mean Barrett's segment length 4.6 cm), who underwent endoscopy for Barrett's esophagus in four study centers, were randomly assigned to undergo either AFE-targeted biopsy followed by four-quadrant biopsies or conventional endoscopic surveillance, also including four-quadrant biopsies (study phase 1). After exclusion of patients with early cancer or high-grade dysplasia, who underwent endoscopic or surgical treatment, as well as those who declined to participate in phase 2 of the study, 130 patients remained. These patients were examined again with the alternative method after a mean of 10 weeks, using the same methods described. The main study parameter was the detection of early cancer/adenocarcinoma or high-grade dysplasia (HGD), comparing both approaches in study phase 1; the secondary study aim in phase 2 was to assess the additional value of the AFE-guided approach after conventional surveillance, and vice versa. Test accuracy measures were derived from study phase 1. RESULTS: In study phase 1, the AFE and conventional approaches yielded adenocarcinoma/HGD rates of 12 % and 5.3 %, respectively, on a per-patient basis. With AFE, four previously unrecognized adenocarcinoma/HGD lesions were identified (4.3 % of the patients); with the conventional approach, one new lesion (1.1 %) was identified. Of the 19 adenocarcinoma/HGD lesions detected during AFE endoscopy in study phase 1, eight were visualized, while 11 were only detected using untargeted four-quadrant biopsies (sensitivity 42 %). Of the 766 biopsies classified at histology as being nonneoplastic, 58 appeared suspicious (specificity 92 %, positive predictive value 12 %, negative predictive value 98.5 %). In study phase 2, AFE detected two further lesions in addition to the initial alternative approach in 3.2 % of cases, in comparison with one lesion with conventional endoscopy (1.7 %). CONCLUSIONS: In this referral Barrett's esophagus population with a higher prevalence of neoplastic lesions, the AFE-guided approach improved the diagnostic yield for neoplasia in comparison with the conventional approach using four-quadrant biopsies. However, AFE alone was not suitable for replacing the standard four-quadrant biopsy protocol.

Adenocarcinoma↗
PubMed2006

Comparison of two PEG-interferon alpha-2b doses (1.0 or 1.5 microg/kg) combined with ribavirin in interferon-naïve patients with chronic hepatitis C and up to moderate fibrosis.

Health regulatory approval of the 1.5 microg/kg body weight dose of pegylated interferon (PEG-I) alpha-2b in combination with ribavirin for the treatment of chronic hepatitis C was based on a study using PEG-I alpha-2b at doses of only 0.5 and 1.5 microg/kg body weight (BW), in spite of the previously shown flat dose-response curve at doses of > or =1.0 microg/kg. Our aim was to compare PEG-I alpha-2b 1.0 microg/kg with 1.5 microg/kg, both in combination with ribavirin. Open-label, randomized study in 227 patients with biopsy-proven chronic hepatitis C (Metavir < or =F2), receiving oral ribavirin (400 mg, twice daily) in combination with subcutaneous PEG-I alpha-2b (1.0 or 1.5 microg/kg, once weekly) for 24 weeks (genotype 2 or 3), or 48 weeks (other genotypes), followed by a 24-week drug-free period. Virologic response rates did not differ between the two doses of PEG-I alpha-2b: in patients infected with hepatitis C virus (HCV) genotype 1 or 4 treated with PEG-I 1.0 microg/kg BW, 38% (22/58) had a sustained virologic response compared with 39% (27/70) in the PEG-I 1.5 microg/kg BW dose group (P = ns). The corresponding values in patients infected with HCV genotype 2 or 3 were 71% (39/55) and 81% (29/36) respectively (P = ns). Adverse events led to transient or permanent dose reductions in fewer patients in the 1.0 microg/kg BW dose group (48/113 patients; 42%) than in the 1.5 microg/kg BW dose group (63/106 patients; 59%, P = 0.015). Furthermore, 89% of patients treated for 24 weeks but only 58% of patients treated for 48 weeks (P < 0.001) tolerated the treatment without relevant dose reduction or premature termination. In combination with ribavirin, PEG-I alpha-2b 1.0 microg/kg was as effective as 1.5 microg/kg but was better tolerated in patients with chronic hepatitis C and up to moderate fibrosis.

Adolescent↗
PubMed2006

HCV-related advanced fibrosis/cirrhosis: randomized controlled trial of pegylated interferon alpha-2a and ribavirin.

In patients with hepatitis C virus (HCV)-related advanced fibrosis/cirrhosis, 30% of sustained HCV clearance has been reported with pegylated interferon alpha-2a (PEG-IFN) alone, but the efficacy and tolerability of the PEG-IFN/ribavirin (RBV) combination remain poorly defined. A total of 124 treatment-naïve patients with biopsy proved HCV-related advanced fibrosis/cirrhosis (Ishak score F4-F6, Child-Pugh score < or =7) were randomized to 48 weeks of PEG-IFN (180 microg sc weekly) and standard dose of RBV (1000/1200 mg po daily, STD) or PEG-IFN (180 microg sc weekly) and low-dose of RBV (600/800 mg po daily, LOW). Sustained virologic response (SVR) rates with PEG-IFN/STD RBV (52%) were higher--albeit not significantly--than that with PEG-IFN/LOW RBV (38%, P = 0.153). In multivariate analysis, genotype 2/3 and a baseline platelet count > or =150 x 10(9)/L were independently associated with SVR. The likelihood of SVR was < 7% if viraemia had not declined by > or =2 log or to undetectable levels after 12 weeks. Nine adverse events in the STD RBV and 15 in the LOW RBV group were classified as severe (including two deaths); dose reductions for intolerance were required in 78% and 57% (P = 0.013), and treatment was terminated early in 23% and 27% of patients (P = n.s.). The benefit/risk ratio of treating compensated HCV-cirrhotics with STD PEG-IFN/RBV is favourable.

Adult↗
PubMed2003

[Levels of psilocybin and psilocin in various types of mushrooms].

Psilocin and psilocybin are psychoactive components of mushrooms of the genus Psilocybe and many others (Panaeolus, Inocybe, Pluteus etc.). In our republic, several species of Psilocybe with a high content of these components can be found. In the present study, we give a semiquantitative content of psilocin and psilocybin in some of our mushrooms in dry substance (Psilocybe semilanceata, Psilocybe bohemica, Psilocybe arcana, Psilocybe cyanescens, Panaeolus acuminatus sensu Ricken, Inocybe haemacta and Pluteus salicinus). For quantification, the GC/MS instrumentation was applied. Psilocin and psilocybin were silylated by the derivatization agent N-methyl-N-trimet-hylsilyltrifluoroacetamide. As an internal standard, 5-methoxytryptamin was used. The results of this study prove the presence of at least three species of Psilocybe with a high content of psychoactive components growing in our republic: Psilocybe semilanceata, Psilocybe bohemica and Psilocybe arcana.

Agaricales↗
PubMed2001

[Pre- and postoperative transaminase changes within the scope of gastric banding in morbid obesity].

UNLABELLED: 20-30% of obese patients without concomitant liver disease show elevated liver tests (ALAT, ASAT, GGT) which are known to normalize after weight reduction. Little is known about the impact of gastric banding on elevated liver enzymes. We investigated the role of gastric banding on weight reduction and liver enzymes in a cohort of patients with morbid obesity. 198 obese patients (166 female, 32 male: median age 37 [19-65] years) with BMI 46 kg/m2 were assessed prior to gastric banding and 6/12 months postoperative for BMI, ALAT, ASAT, GGT respectively. Specific liver diseases were excluded. 37 patients (18.7%) had elevated liver enzymes (ALAT 14.1%, ASAT 9.6%, GGT 6.6%) preoperatively. ALAT and ASAT returned to normal in all patients postoperatively (p < 0.01). In 14 patients with significant ALAT-elevation (i.e. > 10% above normal) we found a correlation between postoperative fall of ALAT and reduction of BMI within 12 month (r = 0.4998; p < 0.05). CONCLUSION: 18.7% of morbid obese patients (BMI 46 kg/m2) have elevated liver enzymes prior to laparoscopic gastric banding. The normalisation of elevated liver enzymes correlates to the extent of weight reduction after gastric banding. Our data show reversible liver enzyme abnormalities, correlating to the degree of obesity.

Adult↗
PubMed2000

Role of lipase in the regulation of postprandial gastric acid secretion and emptying of fat in humans: a study with orlistat, a highly specific lipase inhibitor.

BACKGROUND AND AIMS: To investigate the importance of lipase on gastric functions, we studied the effects of orlistat, a potent and specific inhibitor of lipase, on postprandial gastric acidity and gastric emptying of fat. METHODS: Fourteen healthy volunteers participated in a double blind, placebo controlled, randomised study. In a two way cross over study with two test periods of five days, separated by at least 14 days, orlistat 120 mg three times daily or placebo was given with standardised daily meals. In previous experiments we found that this dose almost completely inhibited postprandial duodenal lipase activity. Subjects underwent 28 hour intragastric pH-metry on day 4, and a gastric emptying study with a mixed meal (800 kcal) labelled with (999m)Tc sulphur colloid (solids) and (111In)thiocyanate (fat) on day 5. Gastric pH data were analysed for three postprandial hours and the interdigestive periods. RESULTS: Orlistat inhibited almost completely (by 75%) lipase activity and accelerated gastric emptying of both the solid (by 52%) and fat (by 44%) phases of the mixed meal (p<0.03). Orlistat increased postprandial gastric acidity (from a median pH of 3.3 to 2.7; p<0.01). Postprandial cholecystokinin release was lower with orlistat (p<0.03). CONCLUSION: Lipase has an important role in the regulation of postprandial gastric acid secretion and fat emptying in humans. These effects might be explained by lipolysis induced release of cholecystokinin.

Adult↗
PubMed2000

Cytomegalovirus-induced transient protein-losing hypertrophic gastropathy in an immunocompetent adult.

Transient protein-losing hypertrophic gastropathy with similarity to Ménétrier's disease is described. Acute infection with cytomegalovirus (CMV) could be shown to play a causative role. Immunodeficiency was ruled out. The 34-year-old patient had complete resolution of the disease without antiviral treatment. To our knowledge the present report is the first case of CMV-associated protein-losing hypertrophic gastropathy in an immunocompetent adult. To date, a similar disorder has only been described in children. CMV infection should be considered in patients with acute and symptomatic protein loss of gastrointestinal origin.

Adult↗
PubMed1999

Evaluation of gastric emptying and motility in diabetic gastroparesis with magnetic resonance imaging: effects of cisapride.

OBJECTIVE: The motor mechanisms that underlie both slow gastric emptying in diabetic gastroparesis and its acceleration by cisapride are poorly understood. We have recently shown that magnetic resonance imaging (MRI) allows concurrent evaluation of both gastric emptying and regional gastric motility. METHODS: Emptying and motility were measured in eight diabetic patients with previously demonstrated delayed gastric emptying using a rapid MRI technique during oral administration of cisapride and placebo. Studies were performed in a double blind fashion and each patient acted as his own control. Subjects were studied supine for 120 min in a 1.5 Tesla MRI scanner after ingestion of 500 ml of 10% Intralipid. Gastric emptying corrected for the volume of secretions was determined every 15 min using transaxial scans. Each transaxial scan was followed by 120 coronal scans at 1 s intervals. Coronal scans were angled to provide simultaneous imaging of the proximal and distal stomach. MRI studies were also performed in seven diabetic patients with normal emptying who served as disease controls. RESULTS: Emptying was slower in the gastroparetic patients (t(1/2): 124 +/- 10 min) compared to patients with normal emptying (81 +/- 9 min, p < 0.05). Cisapride accelerated gastric emptying (74 +/- 5 vs 124 +/- 10 min) in patients with gastroparesis. The contraction amplitudes in the proximal stomach of gastroparetic patients were increased during cisapride treatment (17.2% +/- 1.8% vs 13.2% +/- 0.6%; p < 0.02), whereas antral contraction frequency, amplitude, and velocity were unchanged. CONCLUSIONS: We conclude that cisapride-induced acceleration of liquid gastric emptying in diabetic gastroparesis does not appear to result from changes in antral contractility, but may be related to changes in proximal gastric tone or gastric outlet resistance.

Adult↗
PubMed1998

Effect of lintitript, a new CCK-A receptor antagonist, on gastric emptying of a solid-liquid meal in humans.

The role of cholecystokinin (CCK) in the regulation of gastric emptying of physiological meals containing solids and liquids in humans remains controversial. We studied the role of endogenous CCK in the emptying of a solid/liquid meal administering the new, highly specific and potent CCK-A receptor antagonist lintitript. Gastric emptying was assessed in nine healthy male volunteers using a randomized, double blind, two-period crossover design with oral lintitript (15 mg 1 h prior to meal intake) or placebo on two different days. After ingestion of a pancake (570 kcal) labelled with 500 microCi of 99mTc-sulfur colloid and 500 ml 10% dextrose containing 80 microCi. 111In-DTPA, subjects were studied in a sitting position, using a dual-headed gamma camera. Plasma CCK and pancreatic polypeptide (PP) were measured by a specific RIA. Lintitript distinctly accelerated gastric emptying of solids, while gastric emptying of liquids was not significantly altered. The lag period was shortened by 20% (P<0.05), AUC and half emptying time of solid emptying were lowered by 12% and 13%, respectively (P<0.03). Lintitript markedly increased postprandial plasma CCK release (P<0.001) while distinctly reducing postprandial PP levels (P<0.01) as compared to placebo. These data provide further evidence for a significant role of CCK in the regulation of gastric emptying of solids. The study demonstrates for the first time the marked gastrokinetic properties of the new CCK-A receptor antagonist lintitript in humans.

Adult↗
PubMed1998

Gastric emptying and motility: assessment with MR imaging--preliminary observations.

PURPOSE: To evaluate a magnetic resonance (MR) imaging method for simultaneous assessment of gastric emptying and motility. MATERIALS AND METHODS: Gastric emptying and motility were measured in nine volunteers after ingestion of a liquid meal. A specially designed MR imaging protocol was used that allowed simultaneous assessment of gastric emptying (spatial resolution, 1.5 mm; corrected for gastric secretion volume) and gastric motility (temporal resolution, 1.2 seconds; spatial resolution, 3.1 mm). To evaluate the ability to detect small changes in gastric motor activity with findings from this method, the influence of a prokinetic agent (loxiglumide) on gastric emptying and motility was tested in five volunteers. RESULTS: Each contraction could be individually visualized at MR imaging. Administration of loxiglumide resulted in decreased gastric half-emptying time (mean +/- 1 standard error of the mean, 88.1 minutes +/- 6.3 for the placebo and 39.1 minutes +/- 6.7 for loxiglumide) and increased gastric motility (contraction frequency, 2.26 contractions per minute +/- 0.15 for the placebo and 3.04 per minute +/- 0.04 for loxiglumide). CONCLUSION: MR imaging makes it feasible to study gastric emptying and gastric motility and to determine the influence of drugs on gastric motor activity.

Adult↗
PubMed1997

Role of cholecystokinin in the regulation of liquid gastric emptying and gastric motility in humans: studies with the CCK antagonist loxiglumide.

BACKGROUND: Exogenous cholecystokinin (CCK) inhibits antral motility and slows gastric emptying (GE) but the effect of endogenous CCK on the gastric motor mechanisms responsible for GE remains unclear. METHODS: The effect of the CCK-A antagonist loxiglumide (LOX) on GE and motility was studied using magnetic resonance imaging in six healthy volunteers after ingestion of 500 ml Intralipid 10% (550 kcal). Subjects were studied in the supine position on two occasions during intravenous infusion of LOX (66 mumol/kg/h for 10 min followed by 22 mumol/kg/h) or placebo. GE was determined every 15 minutes using transaxial abdominal scans and motility was studied by means of 120 coronal scans, 1.2 seconds apart. For each coronal image the proximal and distal (antral) diameters were measured at a fixed point in the stomach to determine contraction frequency (ACF) and amplitude (AMP). RESULTS: GE was faster during LOX infusion than placebo (t1/2 31 (22) versus 115 (67) minutes, p < 0.03). There was little variation in the diameter of the proximal stomach with either LOX or placebo. In the distal stomach marked contractile activity was observed during LOX (ACF 2.9 (0.2) versus 1.5 (2.9) during placebo, p < 0.01). AMP also increased during LOX compared with placebo (56 (22)% versus 27 (16)%, p < 0.001). CONCLUSION: The increases in antral motility are likely to contribute to the acceleration of GE and suggest that CCK may regulate GE by acting on the distal stomach although an effect on the proximal stomach cannot be excluded.

Adult↗
PubMed1997

Regulation of gastric and pancreatic lipase secretion by CCK and cholinergic mechanisms in humans.

Gastric lipase (HGL) contributes significantly to fat digestion. However, little is known about its neurohormonal regulation in humans. We studied the role of CCK and cholinergic mechanisms in the postprandial regulation of HGL and pancreatic lipase (HPL) secretion in six healthy subjects. Gastric emptying of a mixed meal and outputs of HGL, pepsin, acid, and HPL were determined with a double-indicator technique. Three experiments were performed in random order: intravenous infusion of 1) placebo, 2) low-dose atropine (5 micrograms.kg-.h-1), and 3) the CCK-A receptor antagonist loxiglumide (22 mumol.kg-.h-1). Atropine decreased postprandial outputs of HGL, pepsin, gastric acid, and HPL (P < 0.03) while slowing gastric emptying (P < 0.05). Loxiglumide markedly increased the secretion of HGL, pepsin, and acid while distinctly reducing HPL outputs and accelerating gastric emptying (P < 0.03). Plasma CCK and gastrin levels increased during loxiglumide infusion (P < 0.03). Atropine enhanced gastrin but not CCK release. Postprandial HGL, pepsin, and acid secretion are under positive cholinergic but negative CCK control, whereas HPL is stimulated by cholinergic and CCK mechanisms. We conclude that CCK and cholinergic mechanisms have an important role in the coordination of HGL and HPL secretion to optimize digestion of dietary lipids in humans.

Adult↗
PubMed1997

Role of lipase in the regulation of upper gastrointestinal function in humans.

The role of lipase in the regulation of upper gastrointestinal function is poorly understood. We studied the effect of orlistat, a new, potent, and highly specific lipase inhibitor, on gastric emptying, cholecystokinin (CCK) release, and pancreaticobiliary secretion. Three groups of studies were performed in nine healthy volunteers, using the double-indicator technique with a triple-lumen duodenal tube, polyethylene glycol 4000 as a duodenal perfusion marker, and 99mTc-diethylenetriamine pentaacetic acid as a meal marker. Gastric emptying, pancreaticobiliary output, and postprandial plasma CCK levels were measured after ingestion of the following isocaloric 500-ml liquid meals with or without 200 mg orlistat: 1) a pure fat meal (10% Intralipid), 2) a meal containing free fatty acids, or 3) an albumin-glucose meal. All experiments were performed in a randomized, placebo-controlled, crossover design. Orlistat markedly inhibited lipase activity in all three experiments. Orlistat given with the fat meal reduced CCK release and output of lipase, trypsin, and bilirubin and accelerated the rate of gastric emptying (P < 0.05). After ingestion of the free fatty acid or albumin-glucose meal, orlistat had no significant effect on any of these parameters. We conclude that lipase plays an important, nutrient-specific role in the regulation of gastric emptying and pancreaticobiliary secretion after ingestion of fatty meals in humans.

Adult↗
PubMed1997

Effects of a specific CCK-A antagonist, Loxiglumide, on postprandial mood and sleepiness.

Previous studies have demonstrated that feelings of sleepiness increase after ingestion of a fat-rich meal. The aim of the study was to test the hypothesis that postprandial sleepiness is mediated by cholecystokinin (CCK) acting on CCK-A receptors. A double-blind crossover study was conducted. Twelve male volunteers ate a high-fat morning meal [54% energy fat, 41% energy carbohydrate (CHO)]. On one day they received an i.v. infusion of Loxiglumide, a CCK-A receptor antagonist (30 mg/kg/h for 10 min then 10 mg/kg/h for 3 h 10 min). On another day the protocol was repeated except a saline placebo infusion was given at similar rates as the Loxiglumide, starting 20 min before the meal. Subjects' mood and sleepiness were monitored throughout using questionnaires and performance tasks. The results indicate that ratings of vigour were significantly lower during the Loxiglumide infusion than during the saline infusion, [F(1,10) = 6.65; p = 0.027]. Subjects who were infused with Loxiglumide on their first test day felt significantly (p < 0.05) more fatigued, sleepy and tense and less vigorous, less efficient and had lower energetic arousal during the Loxiglumide infusion than during the saline infusion. In conclusion, the results suggest that the postprandial decline in feelings of alertness after a fat-rich meal is not mediated solely by CCK acting through CCK-A receptors.

Adult↗