PubMed Health⌕ Search

Biomedical subjects

V Simko

Publications and source records attributed to V Simko.

At least 19 recordsLinked to original sources
PubMed1997

Increased risk in esophageal obstruction with slow-release medications.

Although medication-induced (pill) esophagitis has been recognized for a long time, little data are available on the risk of recently introduced slow-release medications. These formulations may have an obstructive capability (undissolved medication blocking an obstructed lumen) or may cause tissue irritation (continuous leakage from a slowly disintegrating pill). We observed a patient with esophageal carcinoma who developed complete obstruction when three Procardia XL (nifedipine) extended-release tablets blocked the narrowed lumen. An intact Procardia XL tablet and a washed shell as a control were implanted subcutaneously in a rat. The intact pill produced a large inflammatory mass: in contrast, no inflammatory response was noted at the control site implanted with a washed shell. In vitro testing of seven different slow-release medications revealed a wide difference in their solubility at a neutral pH and in gastric juice of pH 1.8 (simulation of esophageal or gastric environment). Theolair-SR (anhydrous theophylline, sustained-release) tablets had the highest obstructive, but no irritating potential. Cardizem SR (diltiazem hydrochloride) sustained-release capsules dissolved promptly without obstructive potential. Adalat CC (nifedipine) extended-release tablets also dissolved early at both pH values. Cardizem CD (diltiazem hydrochloride) extended-release capsules and Calan SR (verapamil hydrochloride) sustained-release oral caplets disintegrated into granules that had a low obstructive potential, but their prolonged presence increased the risk of tissue irritation. Ecotrin (enteric-coated aspirin) tablets had a high obstructive and no irritating potential in the first 24 hours, after which they disintegrated and directly contacted the tissue. Procardia XL extended-release tablets had an insoluble shell that continued to leak a tissue-irritating content even after 48 hours, generating a prolonged obstructive and irritating condition. In conclusion, slow-release medications greatly increase the risk of esophageal injury. Their obstructive and tissue-irritating potentials differ widely. Slow-release formulations should be contraindicated in patients who have obstructive esophageal and gastric disorders.

Aged↗
PubMed1994

Effect of ursodeoxycholic acid on in vivo and in vitro toxic liver injury in rats.

BACKGROUND: Benefits of ursodeoxycholic acid (UDCA) in cholestatic disorders have been well documented. However, the therapeutic potential of UDCA in parenchymal liver disease is unclear. METHODS: We tested UDCA in rat models of hepatotoxicity: (a) in subacute liver injury induced by repetitive CCl4 and dietary ethyl alcohol (ETH) over seven weeks while receiving oral UDCA; and, (b) in liver slides incubated with CCl4, ETH or p-acetaminophen (APAP) when UDCA was added to the incubating solution. RESULTS: Experiment 1: CCl4 combined with ETH reduced the body weights and resulted in 43% mortality. There was a significant rise in serum ALT, alkaline phosphatase, lipoperoxides (LPO) and in hepatic weight, triglycerides, LPO and histological scores of liver injury. Experiment 2: When liver slides were incubated with hepatotoxins there was an increased transfer of AST and LPO from the tissue into the incubate and a reduction in the valine and thymidine incorporation into the liver proteins or DNA. In none of these situations, whether the liver damage was severe or mild, in vivo or in vitro, UDCA did abolish these hepatotoxic effects. CONCLUSION: In contrast to clinical cholestatic disorders where the reported benefits of UDCA depend on replacement of the accumulated hydrophobic bile acids, these bile acids have a less prominent role in toxic liver injury and UDCA is ineffective.

Acetaminophen↗
PubMed1994

Ursodeoxycholic therapy in chronic liver disease: a meta-analysis in primary biliary cirrhosis and in chronic hepatitis.

OBJECTIVES: to determine whether ursodeoxycholic acid (UDCA) is effective in improving primary biliary cirrhosis (PBC) or chronic hepatitis (CH). METHODS: Meta-analysis (MA) was performed on nine papers and three abstracts describing PBC and on nine papers and two abstracts with CH that were published between 1985 and 1992 and were identified through MEDLINE. Studies were included if they fulfilled established quality criteria and the patients had at least liver histology at the start and two to three relevant laboratory tests repeated after UDCA. A total of 800 patients with PBC were treated for 6-48 months. In CH, 285 patients were treated for 1-21 months. RESULTS: In PBC, an average daily UDCA of 13 mg/kg.day improved the liver tests AST, ALT, ALP, and GGT (all p < 0.001). The effect on serum bilirubin was too heterogeneous to evaluate. When evaluated individually, the studies showed an indeterminate effect on histologic progression and treatment failure. When pooled in MA, UDCA improved the liver histology (p < 0.001) and prevented treatment failure (p < 0.04). In CH, UDCA at an average of 11 mg/kg.day improved AST, ALT, GGT, and total bilirubin (all p < 0.001) and also ALP (p = 0.014). There was no effect on histology of CH and no data on treatment failure. CONCLUSIONS: MA confirmed a beneficial effect of UDCA in PBC on liver tests, histology, and treatment failure. In CH, there was an improvement in liver tests, but the evidence for histologic effect was sparse and insignificant. Future studies in PBC must explore the disease after UDCA is discontinued. Trials in CH should distinguish between the diagnostic subgroups, document patient compliance with UDCA, and include histology and treatment failure as end points.

Hepatitis, Alcoholic↗
PubMed1993

Enteroenteric fistula of the duodenum in a patient with AIDS and Mycobacterium avium-intracellulare infection.

Upper gastrointestinal endoscopy revealed a double lumen in the second portion of the duodenum in a 39-year-old man with advanced acquired immunodeficiency syndrome (AIDS). The lesion was not lined with an epithelium and improved with antituberculous therapy. These findings, as well as both an extensive transmural inflammation with foamy macrophages laden with acid-fast microorganisms and the destruction of the bowel wall, were consistent with Mycobacterium avium-intracellulare infection, but not with congenital duplication. An upper gastrointestinal series was falsely negative. Deep, penetrating lesions and double-barreled lumen are not infrequent in AIDS-related esophageal disease. We propose that similar lesions related to M avium-intracellulare occur in the bowel, especially when immune impairment and mycobacterial infection are severe. Awareness of mycobacterial infections of the gut is important in the era of AIDS.

AIDS-Related Opportunistic Infections↗
PubMed1992

Protective effect of oral acetylcysteine against the hepatorenal toxicity of carbon tetrachloride potentiated by ethyl alcohol.

Considering the well-documented protection of acetylcysteine (AC) in hepatotoxicity related to acetaminophen, we studied the preventive potential of AC against mild hepatotoxicity of CCl4, potentiated with ethyl alcohol (ETH) and the role of tissue glutathione. Rats fed a liquid diet with 30% of energy from ETH, had-intraperitoneal CCl4 administered in three injections, at 7-day intervals. AC was ingested at the level for acetaminophen overdose. ETH markedly potentiated the injury induced by CCl4, as evidenced by higher values of serum alanine aminotransferase (ALT), urinary bile acids (BA), serum creatinine, histological score of liver cell necrosis, mortality and by lower body weights and lower liver glutathione, when compared with CCl4 alone. Protective effect of AC consisted of a lesser hepatocytic necrosis, better body weights and higher liver glutathione. We conclude, that AC favorably modifies liver damage induced by CCl4 and potentiated with ETH. There is a preventive role for AC in subjects who combine ETH overuse with exposure to hepatotoxic xenobiotics, whose toxicity is modified by tissue glutathione.

Acetylcysteine↗
PubMed1991

Endoscopic thermometry in healthy controls and in gastroesophageal malignancy.

A thermocouple passed through the biopsy channel of an upper gastrointestinal fiberscope was used to measure mucosal temperature in health and disease. We documented significant mucosal temperature differences at nine sites in 32 normal controls. Duodenal bulb, stomach and the esophagus were warmer than the sublingual site. Mid-esophagus was warmer than the distal esophagus. Next, patients with 50 histologically benign gastric ulcers (GU) were compared with 18 malignant GU containing adeno-div carcinoma. In benign GU there was a marked temperature gradient between a normal reference site (lesser curvature) and a warmer edge (+0.47 degrees C, p less than 0.01) and the crater (+0.73 degrees C, p less than 0.001) of the ulcer. Malignant GU showed no difference to the reference site. In thirteen patients with esophageal cancer, the tumor and also the adjacent mucosa proximal and distal to the tumor were cooler than the corresponding sites in normal controls. Upper GI malignancy appears to have a cooler mucosa. This pattern differs from normal and from non-malignant inflammation. These results support the need for further evaluation of the diagnostic potential of mucosal thermometry, especially of infrared videoendoscopy. (Fig. 1, Tab. 3, Ref. 10).

Aged↗
PubMed1989

Absorptive capacity for dietary fat in elderly patients with debilitating disorders.

To determine the effectiveness of vigorous realimentation with dietary fat, 17 subjects aged 64.0 +/- 2.1 years (mean +/- 1 SEM) were pump-fed via a nasogastric tube for an average of 22 days. The diet was liquid and nutritionally complete, high in unsaturated fat (67% of energy) and in the caloric density (12.6 kJ/mL or 3 Kcal/mL) [corrected]. Advanced malnutrition was manifested by 74% of the ideal body weight, subnormal anthropometric measurements, and low serum protein levels. At an intake of 17,986 +/- 945 kJ (4068 +/- 225 Kcal [corrected]) and 344 +/- 18 g of fat per day, the rate of nutrient absorption was 93% for energy and fat and 88% for protein. An increase in the daily fecal fat to 23 +/- 6 g was not associated with diarrhea. While serum triglyceride levels remained unchanged, the total cholesterol level decreased, with a relative increase in the high-density lipoprotein level. Effective utilization of nutrients resulted in a positive nitrogen balance and increases in body weight, triceps skinfold, the midarm muscle circumference, total iron binding capacity, and serum urea nitrogen level.

Aged↗
PubMed1988

Intestinal absorption of dietary fat from a liquid diet perfused in rats at a submaximum level.

The small intestine of rats was perfused in vivo for 2 h with a nutritionally complete liquid diet (68% calories from fat as corn oil). As the perfusion increased from 106 mg/2 h, the intestinal disappearance of the 14C-triolein marker remained proportional to the load up to 2,359 mg fat/2 h. Despite a decrease in absorption from 70 to 17%, this represents a very large fat intake. Fat absorption improved when medium-chain triglycerides or octanoic acid replaced corn oil (both p less than 0.01). Linoleic acid was absorbed from the diet less than corn oil (p less than 0.01). Dry ox bile reduced fat absorption (p less than 0.05); lipase and an antacid had no effect. Corn oil perfused alone was absorbed better than from the diet (p less than 0.01). Data with 14C-triolein was confirmed by dry-weight disappearance of the diet and by net intestinal water balance. Usual feeding underutilizes a large reserve for fat absorption. This reserve should be considered in therapeutic nutrition.

Animals↗
PubMed1988

Cytomegalovirus associated with acalculous cholecystitis in a patient with acquired immune deficiency syndrome.

Cytomegalovirus (CMV) is an opportunistic organism known to cause significant gastrointestinal pathology in patients with the acquired immune deficiency syndrome (AIDS). Hepatobiliary involvement has previously been documented. In this report, we discuss the rare entity of acalculous cholecystitis associated with CMV intranuclear inclusion bodies in an AIDS patient. The issue of whether CMV is pathogenic, or an associated bystander, is also addressed.

Acquired Immunodeficiency Syndrome↗
PubMed1988

Random urine bile acids in prediction of liver abnormality in asymptomatic alcoholics.

We evaluated bile acids for prediction of abnormal serum liver profile in a random sample of urine (URNBA). Seventy-four subjects with excessive alcohol intake, self-referred for outpatient detoxification, had no history or physical findings of liver disease. Surprisingly, in 49% (36/74) of alcoholics, two or more of these were elevated: serum bile acids, aspartate aminotransferase (AST), alanine aminotransferase, alkaline phosphatase (ALP), and/or total bilirubin. All subjects were subdivided into 39 URNBA normal and 35 URNBA abnormal, using 2.6 mumol/g of creatinine as a dividing value. Serum tests confirmed the subgrouping made with URNBA. Compared with alanine aminotransferase, URNBA had better sensitivity, specificity, and overall diagnostic accuracy predicting abnormal serum bile acids, AST, and alkaline phosphatase values. A predictive potential for a multivariate discriminant function of laboratory tests, known to best identify biopsy-documented mild liver disease, was only mildly inferior for URNBA when compared with AST. Multiple abnormalities of liver test results are unexpectedly frequent in asymptomatic alcoholics. The URNBA are helpful in the detection of liver abnormality in its clinically latent phase, because of the convenience of testing a spot sample of urine.

Adult↗
PubMed1988

Prolapse of gastrostomy tube resulting in entero-enteric fistula and intussusception.

A case is reported in which a surgical gastrostomy tube migrated into the duodenum and eroded through the jejunal wall into an adjacent loop of jejunum. This resulted in an entero-enteric fistula, small bowel obstruction and intussusception. Since the number of gastrostomy tubes being placed endoscopically and surgically is increasing, gastroenterologists and surgeons should be alerted to these and other potential complications.

Aged↗
PubMed1986

Hormonal responses to complete or hydrolyzed protein diets in patients after upper gastrointestinal surgery.

Six gastrointestinal hormones were measured in the plasma of six healthy controls and long-term changes were evaluated in six patients 2-20 years after upper gastrointestinal surgery. In a metabolic unit study we determined fasting hormonal levels, the time to peak hormonal response, and a 135-minute hormonal response to the meal. Test meals were isocaloric, 500 kcal, and isonitrogenous, consisting either of natural breakfast components or of complete liquid diets with intact protein (Ensure) or hydrolyzed protein (Vital). Postsurgical subjects were in good health and had no postcibal complaints. Nevertheless, their hemoglobin and serum albumin were significantly lower than in controls. Postsurgical subjects had higher fasting gastrin (121.3 +/- 11.6 vs 65.4 +/- 6.6 pg/ml, P less than .01) and motilin (148.7 +/- 32.9 vs 70.4 +/- 13.1 pg/ml, P less than .05) than controls. In postsurgical patients the peak gastrin and pancreatic glucagon responses to meals were obtained in significantly shorter time. Their total response to motilin and secretin to meals was significantly lower than in controls. Fasting glucose and the meal-induced responses of insulin and vasoactive intestinal polypeptide were not different from controls. The nature of dietary protein did not significantly affect hormonal responses to feeding. We conclude that gastrointestinal hormonal changes persist many years after surgery. These changes are probably related to faster transit of meals with a generally weaker total hormonal response to feeding. Although these differences from normal may be nutritionally well compensated, they may become important in periods of metabolic stress.

Adult↗
PubMed1986

Bile acid levels in diagnosing mild liver disease. Fasting and postcholecystokinetic values.

In ten healthy controls and in ten patients with biopsy-proved mild liver disease, we studied fasting and postcholecystokinetic bile acid levels to assess their diagnostic value compared with standard liver tests. Cholecystokinetic bile acid elevation was standardized by evacuating the gallbladder with intramuscular ceruletide diethylamine (cholecystokinin decapeptide) in a double-blind, randomized, placebo-controlled crossover design. Radioimmunoassay of primary conjugated bile acids was adequately sensitive to separate controls from patients even on the basis of fasting serum bile acid levels. In both controls and patients, the 180-minute postcholecystokinetic bile acid time curve was significantly higher after ceruletide than after placebo. Nevertheless, neither this response nor any of the 30-minute postcholecystokinetic interval bile acid levels separated controls from patients better than the fasting bile acid values, which discriminated better than standard liver tests or the indocyanine green clearance at 20 minutes. Alanine aminotransferase separated the two groups with a sensitivity equal to fasting bile acid levels.

Bile Acids and Salts↗