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Z Marecek

Publications and source records attributed to Z Marecek.

At least 37 records · Page 2Linked to original sources
PubMed1998

Lipid-protein complexes as cholesterol pronucleating agents in human bile.

Among the various substances which accelerate the formation of cholesterol crystals in cholesterol supersaturated bile are proteins obtained from the bile by affinity chromatography on con A-Sepharose. Several such con A binding proteins have been identified and shown to mediate acceleration of cholesterol crystal formation in vitro. However, the major protein fraction, which does not bind con A, has been studied rarely. Investigation of the effect of this latter bile protein fraction on cholesterol crystallization is the aim of this study. Contrary to results published to date, the con A nonbinding protein fraction exerted a higher cholesterol crystallization promoting activity than the con A binding fraction. Delipidation as well as proteolytic degradation sharply decreased the activity of both fractions. Albumin was identified as the main component of the con A nonbinding fraction. A lipid-protein complex formed from the lipid and albumin possessed a very high cholesterol crystallization promoting activity whereas albumin or the lipid alone showed much lower activity. Bivalent ions, especially Mn2+ and Ca2+, increased the promoting activity of the lipid-protein complex. Thus, albumin and other bile protein can bind noncovalently biliary lipid material and such lipid-protein complexes may act as the main cholesterol crystallization promoter in the human bile.

Albumins↗
PubMed1997

[Hypercalcemia as the first manifestation of bone marrow T-cell lymphoma].

The authors describe the case of a 20-year-old patient where the first leading symptom was hypercalcaemia. A similar case was not published so far in the Czech literature. The disease took a fulminant course and proved fatal nine days after the first symptoms of the disease. The correct diagnosis was established only by necropsy. The adverse course of the disease could not be influenced by repeated haemodialysis nor by the administration of disodium pamidronate (Aredia) and calcitonin. The authors discuss differential diagnostic problems of hypercalcaemias and the pathogenesis of hypercalcaemia in malignant diseases of the haematopoietic system.

Adult↗
PubMed1997

[Tumor markers in the diagnosis of tumors of the liver and biliary tract].

Tumour markers are a valuable contribution to the diagnosis and monitoring of tumours processes in the liver. They are used for early diagnosis as well as for monitoring of treatment. In particular monitoring of the dynamic of changes is important. A dominating place is still held by alpha fetoprotein. The importance of CEA is in differentiation of metastatic processes. In the diagnosis of neoplastic processes in the biliary pathways antigen CA 19-9 is most important. An important finding is also than non-specific increases of tumours markers occur in some chronic processes of the liver and biliary pathways. Despite the large number of tumour markers they are useful only in conjunction with other clinical and imaging methods.

Antigens, Tumor-Associated, Carbohydrate↗
PubMed1997

[Survival after accidental poisoning with a triple lethal dose of paraquat (Gramoxon)].

A case of a 22-year old man who accidentally poisoned himself with a triple lethal dose of organophosphate paraquat (commercially produced as Gramoxon). Owing to the quantity consumed and belated medical treatment, toxicologists initially considered the condition incurable but a complex therapy during a 52-day hospitalization eventually saved the patients's life. Following is an analysis of the case a treatment survey and a discussion of mechanisms that possibly led to the successful result.

Adult↗
PubMed1996

[Treatment of chronic viral hepatitis B with interferon alfa. Experience of the last 3 years].

BACKGROUND: interferon alpha is nowadays the drug of choice in the treatment of chronic viral hepatitis. The objective of the present work was to assess the effectiveness of interferon alpha in the treatment of chronic active hepatitis B in our population and to test whether the known "prognostic factors" of successful treatment are applicable in our patients. METHODS AND RESULTS: In 1991-1994 a total of 25 patients were treated (15 men, 10 women, mean age 46.1 years, range 18-69 years) suffering from chronic active hepatitis B (HBsAg and HBeAG positive) with interferon alpha 2b (Intron A, Schering-Plough International ). Seroconversion to anti-HBe and the drop of serum aminotransferase activity was achieved in 15 patients (60%). Only in one patient within one year after termination of treatment a relapse developed. In the group of successfully treated patients the activity of serum aminotransferases before treatment was significantly higher. The mean duration of the disease was surprisingly longer than in the group where treatment failed (106 vs. 62 months), but this difference was not statistically significant. Only in two successfully treated patients during the second and third month of treatment acute exacerbation of the inflammation occurred and manifestations of hepatic insufficiency with subsequent slow improvement developed. In the remainder the activities of serum aminotransferases declined slowly to normal values.

Adolescent↗
PubMed1995

[Treatment of pancreatic stones with extracorporeal lithotripsy with sonographic localization].

BACKGROUND: Pancreatic stones may be treated by endoscopic extraction or by surgery. Extracorporeal shock wave lithotripsy increased possibility of noninvasive steps to their elimination. The aim of this study was to describe our first experience with this method. METHOD AND RESULTS: 10 patients (6 men and 4 women) in average age 47 years (between 19 to 72 years) were treated. The lithotriptor MEDILIT with sonographic targeting was used for fragmentation of pancreatic stones. Fragmentation was achieved in 8 patients, in 4 cases we observed spontaneous disappearnace, in 3 cases an endoscopic extraction of fragments was necessary. In one case good fragmentation was observed at control ECRP, but the repeated Wirsungography showed a big pseudocyst which had not been diagnosed at the first examination and surgery was necessary. In 2 cases no fragmentation was achieved and in these cases surgery was also indicated. No serious side effects were observed, nor elevation of amylase values compared with the situation before the shock wave treatment. CONCLUSIONS: Extracorporeal shock wave lithotripsy of pancreatic stones revealed good fragmentation and disappearance stone from ductus Wirsungi without serious side effects on clinical course and surrounding soft tissues.

Adult↗
PubMed1995

[Tumors of the biliary tract: possibilities of multimodality therapy].

BACKGROUND: Tumours of the biliary system (NBS) account for as many as 16% of all tumours of the GIT. Early diagnosis is difficult, contemporary treatment is not satisfactory and the prognosis is poor. It seems that one of the few therapeutic perspectives is multimodal treatment. The objective of the present work is to assemble experience with multimodal treatment of NBS. METHODS AND RESULTS: From January 1987 to December 1993 347 patients with NBS were treated, using bilioduodenal endoprostheses (BDE). In 26 patients treatment was supplemented by regional chemotherapy, in 10 by intraluminal radiotherapy, using lr 192. Average periods of survival:BDE 230 days, BDE+regional chemotherapy 662 days. Endoprostheses+intraluminal radiotherapy-survival period 96-293 days. The investigation has not yet been completed, as the majority of patients still survives. CONCLUSIONS: Implantation of BDE combined with regional chemotherapy significantly prolongs the life of patients with NBS. It seems that similar results will be obtained also by a combination of BDE and intraluminal radiotherapy. Multimodal treatment of NBS can be nowadays considered the method of choice in the treatment of tumours in this region.

Adult↗
PubMed1995

[Biliary-duodenal prosthesis in the palliative treatment of tumors in the subhepatic region].

In the group of 347 patients (pts) with biliary cancer (218 females and 129 males, age range 42-88 years), the large size bilio-duodenal endoprostheses (BDE) were inserted. The success rate in BDE implantation varied from 68 to 92% according to the localisation of the common bile duct stenosis and its anatomy. The BDE introduction was followed by step-by-step normalisation in laboratory markers of biliary obstruction in 76% of pts, the full functional capacity of BDE varied from 26 to 311 days (median 168 days). In pts treated by BDE the survival median was 210 days. Early complications did not exceed 2.2%, late complications were observed in 8% out of cases. The 30-day mortality was 1.7%.

Adult↗
PubMed1995

[Therapy of chronic cholestasis].

Therapy of chronic intrahepatic cholestasis is either symptomatic or causal. Symptomatic treatment is focused above all on treatment of pruritus - in the treatment an important place is held by the administration of cholestyramine and Rifadine; administration of opiate antagonists is very promising. In the causal treatment administration of ursodeoxycholic acid predominates. Its favourable effect was proved in several controlled studies. It is useful in primary biliary cirrhosis and primary sclerotizing cholangoitis, however, also in other types of cholestasis. In advanced cases it is a useful starting point for transplantation of the liver.

Cholestasis, Intrahepatic↗
PubMed1994

[Renal resistance to atrial natriuretic factor as a cause of the escape failure phenomenon in patients with non-ascitic liver cirrhosis].

BACKGROUND: Chronic administration of synthetic mineralocorticoids leads in healthy subjects only to temporary fluid retention with subsequent restoration of sodium balance, i.e. the so-called mineralocorticoid escape phenomenon. There is a failure of mineralocorticoid escape in patients with ascitic liver cirrhosis with progressive fluid retention. The aim of this study was to contribute to the elucidation of the mechanisms of the escape phenomenon in patients with preascitic liver cirrhosis. METHODS AND RESULTS: Synthetic mineralocorticoid, fludrocortisone, was administered for 7 days to 8 patients with non-ascitic liver cirrhosis (LC) and 6 controls (CO) on a high sodium diet. CI seemed to have some central volume expansion before fludrocortisone administration, as assessed from a higher left atrial diameter and lower plasma aldosterone. Fludrocortisone administration in CI led to a comparable increase of ANF and suppression of plasma aldosterone as in CO with a higher diameter of the left atrium and lower PRA than in controls. Despite a comparable increase of ANF after fludrocortisone administration cGMP excretion was significantly higher in CO than in CI (434.5 + 247.1 vs. 824.6 + 317.3 pmol/min, p < 0.05). Natriuresis of CI seemed to depend on urinary cGMP excretion before fludrocortisone administration. The natriuretic response of these CI to a high sodium diet was exaggerated (290.0 + 53.9 vs. 160.0 + 18.3, p < 0.05), but they were unable to escape completely from the retaining effect of fludrocortisone. CONCLUSIONS: Failure of mineralocorticoid escape in patients with preascitic liver cirrhosis may be due to the renal resistance to ANF with insufficient increase of urinary cGMP excretion.

Adult↗
PubMed1993

[Initial experience with the transjugular renal biopsy].

Transjugular renal biopsy is a new diagnostic method used for collection of tissue specimens for morphological examination in some indicated cases where the use of the standard percutaneous technique involves risk. The method has not been used so far in Czechoslovakia.

Biopsy, Needle↗
PubMed1991

[The effect of diltiazem on hemodynamic parameters in patients with liver cirrhosis].

Previous investigations of authors abroad provided evidence of a reduction of portal pressure by blockers of slow calcium channels group II by verapamil. We decided to investigate the effect of a quite new preparation dilthiazem on the portal haemodynamics in patients with compensated cirrhosis of the liver and oesophageal varices. Doppler examinations of the width, rate of blood flow and flow through the trunk of the portal vein did not prove a statistically significant effect of dilthiazem on the investigated parameters. After the preparation a significant decline of the median pressure in the pulmonary artery was recorded at the 5% level of significance. The significantly elevated pressure values in the wedged position in the hepatic vein (WHVP) as well as of the portohepatic gradient (P-H) rose further after administration of the preparation (WHVP by 12.3%, p P-H by 15%). Even maximum doses of dilthiazem did not influence the portal flow in patients and did not lead to a reduction of the portohepatic gradient. From the results it is apparent that dilthiazem is not suitable for the treatment of portal hypertension.

Diltiazem↗
PubMed1991

[Bile acids in the treatment of cholestatic lesions of the liver].

The authors give an account of their own experience with one-year treatment of primary biliary cirrhosis with ursodeoxycholic acid (Ursofalk). From the investigation ensues: 1. Treatment must be started as soon as possible, best in the first or second stage of PBC (without cirrhotic transformation). In later stages a favourable reaction is rather exceptional and an adverse effect on portal hypertension cannot be ruled out. 2. It is better to start treatment with low doses (250 mg/day) and increase the dose gradually, depending on tolerance. A dose of 500 mg/day usually proves sufficient, but the dose can be raised even to 750 mg/day. 3. During treatment not only clinical improvement is achieved but also a favourable effect on laboratory findings, i.e. cholestatic (ALP and GMT) as well as on the activity of the disease (aminotransferases) is recorded. 4. After discontinuation of the drug and after its prolonged administration and marked improvement a relatively brisk deterioration of clinical and laboratory findings occurs. Therefore treatment must be prolonged. In primary sclerotizing cholangitis hitherto assembled experience is very favourable, but the investigation is too short so far (months). Also proper evaluation of treatment requires a longer follow up period, treatment with ursodeoxycholic acid in the initial stages of primary biliary cirrhosis and in sclerotizing cholangitis is promising. This is important among others because other therapeutic possibilities are so far lacking in this disease.

Female↗
PubMed1991

[The effect of glucagon on portal hemodynamics in patients with liver cirrhosis].

The authors assessed in 12 patients with compensated cirrhosis of the liver, portal hypertension and oesophageal varices, using a Doppler flowmeter Toshiba SAL 50A/SDL 01 under basal conditions, changes in the width, rate of blood flow and blood flow though the trunk of the portal vein before and after intravenous administration of 1 mg glucagon. The width of the trunk of the portal vein did not change significantly during assessment. A statistically significantly increased flow through the portal vein was recorded starting during the 5th minute, and it correlated with the increased velocity of the blood flow. The increased flow persisted to the 20th minute after glucagon administration. The drop of pressure in a wedged position assessed in the hepatic veins after administration of the drug was not significant, the pressure in the free hepatic vein increased insignificantly. On the whole the portohepatic gradient declined by 10.5%, the drop was not significant. Glucagon in pharmacological doses has an early onset of action even in cirrhotic subjects whereby the increased flow through the portal vein does not lead to a rise of the portohepatic gradient. Glucagon administration thus does not increase the risk of haemorrhage from oesophageal varices during acute fibroscopy of the oesophagus and stomach in patients with portal hypertension.

Blood Flow Velocity↗
PubMed1991

[Distal renal tubular acidosis in patients with Wilson's disease].

Renal affection is part of the clinical picture of developed Wilson's disease. The most frequent sign of affection of the distal nephron is distal tubular acidosis (DRTA), more frequently its latent form with a normal systemic pH, but inability to reduce the urinary pH below 5.5 after an acid load. More detailed assessment of the type of this disorder was not made so far. To elucidate in greater detail the pathogenesis of DRTA in Wilson's disease the authors examined renal acidification in 13 patients with bioptically verified Wilson's disease, using three acidification tests: 1) the test involving oral administration of calcium chloride (CaCl2), 2) the test involving infusion of sodium sulphate (Na2SO4) and 3) the test using an infusion of NaHCO3. In none of the examined patients with Wilson's disease manifest (complete) DRTA was found with systemic acidosis, however, in five patients latent (incomplete) DRTA was revealed, i.e. after administration of CaCl2 the pH of urine did not decline below 5.5. Patients with Wilson's disease and DRTA differed from patients with Wilson's disease and normal renal acidification by the age at the time of assessment of the diagnosis (30.4 +/- 3.6 vs. 20.75 +/- 2.14 years, p less than 0.02) and the duration of the disease (i.e. the time from assessment of the diagnosis to the acidification examination: 4.6 +/- 4.86 vs. 15.38 +/- 2.40 years, p less than 0.01). In three of four patients with Wilson's disease and DRTA who were given Na2SO4, after its administration the pH of urine did not decline below 5.2.(ABSTRACT TRUNCATED AT 250 WORDS)

Acidosis, Renal Tubular↗
PubMed1991

[Hypertension in patients with polycystic kidneys--the effect of volume expansion].

Arterial hypertension is found in as many as 75% patients with autosomal dominant polycystic kidneys with normal renal function, its pathogenesis is however not quite clear so far. The authors examined 16 patients with polycystic kidneys with normal or only slightly reduced renal function (plasma creatinine lower than 140 umol/l), 8 of these patients were normotonic (N) and 8 hypertonic (H). In all examined subjects right-sided cardiac catheterization was performed with assessment of the minute cardiac volume by thermodilution. To all patients in the course of one hour 1500 ml saline per 70 kg body weight were administered and the haemodynamic examinations were repeated after termination of the infusion. In all subjects before and after expansion the plasma renin activity was assessed (PRA), as well as plasma aldosterone (PA), plasma catecholamines (PC) and the atrial natriuretic factor (ANF), the renal blood flow and glomerular filtration by means of clearance and extraction of PAH and inulin clearance. The authors did not find differences in plasma concentrations, cardiac output and splanchnic and renal ANF extraction in groups N and H, nor in PRA, PA and PC. Volume expansion led in both groups to a comparable rise of ANF and suppression of PRA and PA. Group H did not differ from group N in any of the investigated haemodynamic and renal parameters except for systemic vascular resistance. In hypertensive patients before expansion a close correlation was found between pressure in the pulmonary artery in a wedged position and diuresis (r = 0.935, p less than 0.01) and natriuresis (r = 0.895, p less than 0.01). The volume expansion was in both groups associated with a comparable rise of diuresis, the haemodynamic response of patients N and H was however quite different. While in patients of group N a decline of the systemic vascular resistance occurred as well as an increase of the minute volume without a change of the renal flow and glomerular filtration, in hypertonic patients the systemic vascular resistance and minute volume did not change but there was a significant rise of the renal flow and glomerular filtration. The relationship of diuresis and natriuresis of hypertensive patients with polycystic kidneys to volume parameters and the rise of the renal perfusion pressure during volume expansion indicates the importance of pressure natriuresis for ensuring the sodium and volume homeostasis in these patients.

Humans↗