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J Bures

Publications and source records attributed to J Bures.

At least 19 recordsLinked to original sources

Intraoperative enteroscopy: ten years' experience at a single tertiary center.

BACKGROUND AND METHODS: Intraoperative enteroscopy is an invasive technique for small bowel investigation. It enables us to investigate the entire small intestine and to treat pathological findings by endoscopic or surgical means at the same time. The investigation is invasive and that is why the proper indication is mandatory. RESULTS: Forty-one intraoperative enteroscopies were performed at our center within a 10-year period. The procedure was diagnostic in 37/41 patients (90.2%); in 3 patients no pathology was found, and in 1 patient we found only previously diagnosed celiac disease. The investigation was therapeutic in 35/41 (85.4%) patients; 2 patients with small bowel ulcers did not require any intraoperative therapy. The pathological findings were arteriovenous malformations (found in 12 patients), small bowel NSAID-induced or Crohn's ulcers (8 patients)--ulcerations and arteriovenous malformations were simultaneously found in three patients; carcinoid of the small intestine (5 patients); Peutz-Jeghers syndrome (5 patients); bleeding polyps (2 gastrointestinal stromal tumors, 1 paraganglioma, and 1 lipoma--in 4 patients); Rendu-Osler-Weber disease (2 patients); multiple cavernous hemangiomas in blue rubber bleb nevus syndrome (1 patient); Henoch-Schönlein purpura (1 patient); aortoenteral fistula (1 patient); and retrograde intussusception of Meckel's diverticulum (1 patient). In five patients with Peutz-Jeghers syndrome, 6-22 hamartomas (median of 18 per session) were removed by means of endoscopic polypectomy during intraoperative enteroscopy. There were no major procedure-related complications in our series. CONCLUSIONS: Intraoperative enteroscopy is accepted as the ultimate diagnostic procedure for complete investigation of the small bowel. Despite the introduction of double-balloon enteroscopy into clinical practice, intraoperative enteroscopy will be reserved for those cases where double-balloon enteroscopy cannot be performed or fails to investigate the entire small intestine, especially to prevent excessive bowel resection.

Adolescent↗

[Mean platelet volume (MPV) in Crohn's disease patients].

BACKGROUND: Platelets are involved in the pathogenesis of chronic inflammation. Thrombocyte count and platelet volume are considered as a useful activity marker of inflammatory bowel disease. The aim of the study was to compare the yield of mean platelet volume with clinical and other laboratory markers of activity in Crohn's disease (CD). METHODS AND RESULTS: A total of 56 patients with CD were investigated at time of evident clinical relapse and remission (29 males and 27 females, aged 19-68 years, mean 34.5, median 31.5 years). Complete blood count, C- reactive proteins were measured. Disease activity was assed by the Crohn's Disease Activity Index (CDAI). Patients were checked at least twice (120 analyses were carried out in total). Thrombocytosis (above 350xl09/L) was found in 32/61 (52 %) patients with clinical relapse and in 7/59 (12 %) patients with clinical remission (mean 400.7x10(9)/1; 95%CI: 361.1-440.3x10(9)/1; or as the case may be mean 278.6xl0(9)/1; 95% CI: 256.8-300.4x10(9)/1). The mean platelet volume decreased (under 7.8 fL) in 19/61 (31 %) patients with clinical relapse and in 8/59 (13.5 %) with clinical remission (mean 8.333 fl; 95% CI: 7.935-8.731 fl; or as the case may be mean 9.200 fl; 95% CI: 8.824-9.576 fl). Total platelet count, CDAI and C- reactive protein were significantly increased (p<0.0001) and mean platelet volume was statistically significantly reduced (p=0.003) during clinical relapse compared with clinical remission. CONCLUSIONS: Decreased mean platelet corpuscular volume is an independent laboratory marker of clinical disease activity. However, on the basis of our study, its predictive value is inferior compared to the total platelet count, serum concentration of C- reactive protein and Crohn's disease activity index.

Adult↗

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↗

[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↗

From spreading depression to spatial cognition.

The Laboratory of Neurophysiology of Memory started its existence in 1954 by systematic research into spreading depression of EEG activity of laboratory rodents and by the use of this remarkable phenomenon as a functional ablation method in behavioral research. Its main contributions were in the study of memory formation and consolidation, interhemispheric transfer, motor learning, conditioned taste aversion and spatial orientation and navigation. In the last five years it concentrated on navigation of rats in multiple reference frames, on electrophysiological evidence for the role of hippocampal place cells support of behavior in such dissociated frames, on the analysis of idiothetic and allothetic forms of navigation and on the mathematical methods allowing assessment of the contribution of goal directed locomotion to place cell activity. The methods used in spatial memory research in rats were used for examination of human subjects in a laboratory equipped with a tracking system for humans in the hospital Homolka. Animal models of Alzheimer disease were studied in transgenic mice with the human gene for the beta amyloid precursor protein.

Animals↗

[Dysmotility disorders of the stomach and possible methods of diagnosis].

Gastric dysmotility disorders are markedly heterogeneous group of gastrointestinal tract disorders and their etiology vary substantially. Some clinical manifestations of gastric dyspepsia can be present but they could be clinically silent, too. The authors give an overview of recent possibilities of dysmotility disorders diagnostics and of their relation to diabetes mellitus.

Diabetes Complications↗

[Clinical importance of Helicobacter pylori infection in patients with diabetes mellitus].

This paper provides a review of current literature on Helicobacter pylori infection in diabetes mellitus. According to majority of studies there is no difference of Helicobacter pylori infection prevalence between diabetes mellitus and general population. There is no role of Helicobacter pylori in etiopathogenesis of diabetes. The only finding of Helicobacter pylori itself has not been an indication for eradication therapy in diabetes. In case of anti-helicobacter therapy (due to another indication) eradication rate is lower in diabetics (compared to non-diabetics) and there is a higher risk of re-infection (compared to general population). Several issues (especially dysmotility disorders of the stomach and influence of Helicobacter pylori eradication for the control of diabetes) remain controversial.

Diabetes Mellitus↗

Veterinary autogenous vaccines.

Autogenous vaccines remain a regulatory issue. They are demanded by practising veterinarians and by animal owners and they are quite widely used, mainly in Central European Countries, the Czech Republic, Hungary and Slovak Republic having probably the longest tradition with these products in Central Europe. The scope given in Article 3, Para. 2 (and/or Article 4 for some countries) of Directive 2001/82/EC applies to these products in the Acceding Countries. As these products are exempt from the harmonised regulation at the EU level, they are regulated by individual countries, the regulation varying from practically no regulatory measures in certain countries to a quite complex and demanding regulation in the other countries. Both risks and benefits are related to these products and they shall be taken into account when regulatory measures are considered. The major risks related to veterinary autogenous vaccines relate to possibility of transmission of TSE agents or other viral, bacterial and/or fungal contaminants. As appropriate and well balanced regulation of these products is deemed necessary, considering the risks related to these products, and based on the fact that national regulatory measures could be considered as a trade barrier under certain circumstances, harmonisation of the key issues or legal admission of the nationally based regulatory measures, including movement of these products from the other Member States, shall be laid down in the EU legislation. The veterinary autogenous vaccines complying with basic quality and safety requirements are thus a very useful tool in the animal health and welfare management but their use should be restricted to situations where there is no authorised veterinary medicinal product available and veterinary autogenous vaccines must not be allowed to replace good farming or veterinary practices.

Animals↗

[Gastric and duodenal ulcers--etiopathogenesis, diagnosis and therapy at the milestone of the 20th century].

Peptic ulcer disease has been still very actual topic as 10% of western population would fell ill during its life. Substantial changes in understanding of etiopathogenesis were achieved within last hundred years. The first milestone means development of gastric physiology (gastric secretion, histamine, gastrin, cyclo-oxygenase, H2-receptors, proton pump). There is no doubt peptic ulcer is a typically human disease with involvement of the cortico-visceral axis and psychosomatic traits. Others factors play their role in the etiopathogenesis (like genetic, ethnic, environmental and socio-economic factors). However, main etiologic factors are Helicobacter pylori (approximately 90% duodenal and 50% gastric ulcers) and non-steroidal anti-inflammatory drugs (approximately 30% gastric and 10% duodenal ulcers). Diagnostics were determined by technical progress most of all by the construction of flexible digestive endoscopes into clinical practice. Surgery has been step by step replaced by pharmacotherapy (H2-receptor antagonists, proton pump inhibitors, Helicobacter pylori eradication). In near future we can expect further decrease in prevalence of peptic ulcer disease and gastric cancer in developed countries and increase in gastro-oesophageal reflux disease. Let us hope that current controversies in indication of eradication therapy will be overcome by vaccination against Helicobacter pylori.

Helicobacter Infections↗

Operant behavior can be triggered by the position of the rat relative to objects rotating on an inaccessible platform.

The present study describes a task testing the ability of rats to trigger operant behavior by their relative spatial position to inaccessible rotating objects. Rats were placed in a Skinner box with a transparent front wall through which they could observe one or two adjacent objects fixed on a slowly rotating arena (d = 1 m) surrounded by an immobile black cylinder. The direction of arena rotation was alternated at a sequence of different time intervals. Rats were reinforced for the first bar-press that was emitted when a radius separating the two adjacent objects or dividing a single object into two halves (pointing radius) entered a 60 degrees sector of its circular trajectory defined with respect to the stationary Skinner box (reward sector). Well trained rats emitted 62.1 +/- 3.6% of responses in a 60 degrees sector preceding the reward sector and in the first 30 degrees of the reward sector. Response rate increased only when the pointing radius was approaching the reward sector, regardless of the time elapsed from the last reward. In the extinction session, when no reward was delivered, rats responded during the whole passage of the pointing radius through the former reward sector and spontaneously decreased responding after the pointing radius left this area. This finding suggests that rats perceived the reward sector as a continuous single region. The same results were obtained when the Skinner box with the rat was orbiting around the immobile scene. It is concluded that rats can recognize and anticipate their position relative to movable objects.

Animals↗

Treatment of patients with achalasia with botulinum toxin: a multicenter prospective cohort study.

Botulinum toxin (BT) injection is an alternative treatment of achalasia. The aim of the study was to examine outcomes of patients treated with BT in the Czech Republic. Since 1997, 49 patients with achalasia have been treated with BT. We prospectively evaluated the effect of BT injection on 41 patients during a median follow-up of 24 months (range 9-62). Esophageal manometry was performed before and at 3-5 months after the injection. In 16 patients, BT was injected from the antegrade angle only (subgroup A), in 15 patients, BT was injected from both retrograde and antegrade angles (subgroup B) and, in 10 patients, BT injection was combined with subsequent balloon dilatation (subgroup C). Immediate clinical response was achieved in 93% of patients. Clinical remission was sustained beyond 3 months in 83% of patients (responders). Fourteen responders (41%) did not experience a relapse during the median of 22 months. Twenty responders (59%) experienced symptomatic relapse approximately 8 months after the injection. Ten relapsers underwent BT reinjection, five (50%) of them were asymptomatic for another 14 months. The remaining five (50%) patients reported a second relapse approximately 6 months after the reinjection. Median duration of the symptom-free period was 11.5 months after the first BT injection, and 10.5 months after the second (P = 0.21). We did not find any significant predictor of a favorable outcome; responders tended to be older and to have a lower basal lower-esophageal-sphincter pressure. Patients in subgroup C were more likely to be in remission at 1 and 2 years as compared with patients in subgroup A. BT injection is an effective treatment of achalasia in the short term. However, almost 70% of patients experience a relapse within 2 years. BT injection should therefore be reserved for patients at risk for more invasive procedures or for patients who prefer this treatment.

Adolescent↗

[Intraoperative enteroscopy--personal experience from 1995 to 2002].

Authors present their experience with the intraoperative enteroscopy method--an invasive technique of small bowel examination. It is performed under narcosis at an operating theatre (i.e. in co-operation with surgeon and anaesthesiologist). The endoscopy-performing physician becomes one of the members of the operating team. The advantage of the method is the possibility to examine of the whole small intestine and to solve immediately the pathological findings by endoscopic or surgical intervention. The examination is invasive and the correct indication is mandatory. Authors report their results of 18 intraoperative panendoscopies of small intestine.

Adult↗

[Effects of nonsteroidal anti-inflammatory agents on the gastrointestinal tract].

Non-steroidal anti-inflammatory drugs (NSAID) belong to the most commonly used drugs worldwide. NSAIDs can cause serious side effects to the gastrointestinal tract. During NSAIDs treatment 10-12% patients suffer from dyspepsia. Up to 1% patients develop severe gastrointestinal complications (ulcer, bleeding, perforation). Any part of gastrointestinal tract could be affected. In oesophagus, NSAIDs can cause oesophagitis of fibrous stricture. NSAID gastropathy can be detected in 40% patients chronically treated with NSAIDs. NSAIDs toxic injury to small and large bowel is frequent but only seldom properly recognised. Serious hepatic lesions are rare. There is no fully reliable and sure prophylaxis or treatment of NSAIDs impairment of to the gastrointestinal tract. Rate of side effects can be reduced by reasonable prescriptions and by primary and secondary prophylaxis. Low rate of side effects is associated with the use of pro-drugs (compound is metabolised to an active substance after absorption from the gastrointestinal tract). New promising drugs were developed with dual action (5-lipoxygenase- and COX-inhibition) and NSAID releasing NO (nitronaproxen, nitrophenac). Specific COX-2 inhibitors (coxibes) provide comparable anti-inflammatory and analgesic effect but the risk of serious side effects to the gastrointestinal tract is significantly lower (when compared with non-specific NSAIDs). Beside harmful effects, NSAIDs are powerful tool in chemoprevention of colorectal cancer.

Anti-Inflammatory Agents, Non-Steroidal↗

[Epithelioid hemangiosarcoma of the thyroid gland].

Authors present a case of epithelioid haemangiosarcoma of the thyroid gland in a 54-year-old female with a history of eufunctional nodular goitre. The patient was treated by total thyroidectomy with extirpation of cervical lymph nodes and by subsequent chemotherapy. The tumour behaved highly aggressively with early generalization and unusual way of metastatic spread into the wall of the stomach and duodenum. The patient died 3 months after the surgery due to therapeutically unmanageable bleeding into the GIT. The clinico-pathological aspects of the case are discussed.

Female↗

Relative contribution of allothetic and idiothetic navigation to place avoidance on stable and rotating arenas in darkness.

In the absence of useful visual or other exteroceptive cues, rats can orient in their environment using idiothetic navigation, the process in which the information generated during self-motion is integrated to yield a homing vector leading the animal back to a point of departure. If perceivable exteroceptive cues in the visited environment are available, their spatial relationship is integrated with idiothetic information and stored in a cognitive map of the environment. Our previous experiments demonstrated that place navigation in rats is severely impaired after devaluation of the intramaze substratal information by shuffling, i.e. by its random displacement relative to the already traversed track. Several interpretative difficulties of the previous study have been eliminated in the present study by the use of an advanced version of the shuffling apparatus. The results show that shuffling-induced impairment of substratal idiothesis depends on the salience of intramaze cues, that on a stable featureless arena, idiothesis can be updated by non-visual allothetic cues, and that shuffling exposing the animal to sudden accelerations and decelerations interferes with idiothetic navigation by the inherent conflict between substratal and inertial idiothesis. It is concluded that pure substratal idiothesis not updated by extramaze and intramaze cues cannot provide reliable navigation over distances longer than 5 m.

Animals↗