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Biomedical subjects

Y Bujanover

Publications and source records attributed to Y Bujanover.

At least 37 records · Page 2Linked to original sources

Protein-restricted diet alters concentration of plasma membrane glycoproteins in rat liver.

Malnutrition is known to have adverse effects on the physiology and morphology of the liver. The aim of this investigation was to examine the effect of protein restriction on the content of plasma membrane proteins residing in the sinusoidal and bile canalicular domains of rat liver. Post-weanling rats maintained on low protein isocaloric diets showed marked growth retardation concomitant with reduced liver protein concentration compared to control animals. The content of leucine aminopeptidase, a bile canalicular enzyme, and asialoglycoprotein receptor, a sinusoidal receptor, in livers of protein-restricted rats was 66% and 50%, respectively, of control livers. In contrast, the relative concentrations of dipeptidyl peptidase IV and a cell adhesion molecule (GP 110), both canalicular proteins, were 160% and 121%, respectively, in rat livers upon protein restriction. After a 4-week rehabilitation period, the concentrations of all canalicular membrane proteins were similar to those in control livers, while the sinusoidal receptor was only 68% of control values. Protein restriction was found to adversely affect the concentrations of protein constituents, but not their localization in the hepatocyte plasma membrane. In general, altered concentrations of hepatocyte membrane proteins were reversed on the administration of a normal protein diet.

Animals↗

Helicobacter pylori and peptic disease in the pediatric patient.

The data accumulated on Helicobacter pylori infection in children suggests an important causative role of the organism in gastritis and peptic ulcer disease in this age group. The importance of eradication of H pylori in asymptomatic children in relation to its role in peptic disease and cancer in adults is debatable. This article describes the current data on bacteriologic features, pathologic spectrum, clinical significance, epidemiology, methods of diagnosis, and treatment of H pylori infection in children. Further studies will provide the information on the pathogenicity, mode of transfer, and optimal treatment of H pylori infection.

Adolescent↗

One week triple therapy with omeprazole, clarithromycin and tinidazole for Helicobacter pylori: differing efficacy in previously treated and untreated patients.

BACKGROUND: Triple therapy with omeprazole, clarithromycin, and tinidazole (OCT) has been found to be highly effective against Helicobacter pylori infection. However, its efficacy as a second line regimen for patients who failed metronidazole-based triple therapy has not been evaluated. AIM: The aim of this study was to evaluate the efficacy of low-dose, short-term OCT therapy in an Israeli population, and to compare results obtained in previously treated and untreated patients. METHODS: Patients with duodenal or gastric ulcers and chronic antral gastritis with H. pylori infection as assessed by rapid urease test and/or 14C urea breath test (14C-UBT), were studied. All patients received omeprazole 20 mg b.d., clarithromycin 250 mg b.d. and tinidazole 500 mg b.d. for 7 days. Eradication was assessed by 14C-UBT 4 weeks after treatment. RESULTS: One hundred and fourty-four patients (M/F = 81/63) were enrolled (mean age 48.1 years, range 12-78). Eradication of H. pylori was significantly different between patients who were initially treated with this regimen (90/94, 96%) and patients who had previously failed to eradicate H. pylori with standard triple therapy (27/50, 54%). Moreover, the eradication rate was significantly decreased in patients with more than one previous failure (9/22, 41%) compared to that in patients with only one failure (18/29, 62%). No other differences such as age, gastric pathology, ethnic origin, smoking habits, or pre-treatment urease activity were found to influence the eradication rate. CONCLUSIONS: One-week low-dose triple therapy with OCT is highly effective as an initial therapy in eradicating H. pylori infection. The efficacy is significantly lower when given as a second line treatment in patients who have previously failed to eradicate H. pylori with bismuth-based standard triple therapy.

Adolescent↗

Characteristics of gallbladder bile of infants and children.

In the past, biliary lipids of infants and children were studied in duodenal aspirates. This study was performed on original bile aspirated from the gallbladder. The analysis of lipids in bile demonstrated a significantly lower total lipid content in the bile of infants than in children (3.3 g/dl vs. 9.1 g/dl). The most prominent difference was demonstrated in the bile salt concentration (43.2 mM vs. 126.7 mM) and thereafter in the phospholipid content. Infants had a shorter nucleation time and a higher cholesterol saturation index than did children. These results may explain the increased tendency of infants to produce sludge and gallstones during total parenteral nutrition.

Bile↗

Immune response to hepatitis B virus vaccine in 1-year-old preterm and term infants.

The recent mass immigration to Israel from the former U.S.S.R. and Ethiopia has significantly increased the hepatitis B virus (HBV) carrier rate. Since January 1992, all newborns in Israel have been routinely immunized against HBV. The same routine of vaccination has been used for premature and term newborns. The aim of the present study was to investigate the immune status against HBV in term and preterm infants at the age of 1 year. All infants were vaccinated at day 1 and at 1 and 6 months with Engerix. Hepatitis B antigen antibody (Ab) serum titers were determined at the age of 1 year. All infants had detectable Ab titers (responders); 92.5% had protective titers (> 10 mlU/ml), out of which 26.5% were low responders (< 100 mlU/ml) and 65% were high responders (> 100 mlU/ml). There was no significant difference in immune responses between term and preterm infants.

Female↗

Increased leukocyte adhesiveness/aggregation is the single best biochemical indicator of disease activity in adolescent patients with inflammatory bowel disease.

We determined the relative utility of inflammatory markers in evaluating disease activity in adolescent patients with inflammatory bowel disease (IBD). Sixty-one adolescent patients and 50 age and sex matched volunteers who served as controls were evaluated prospectively. The erythrocyte sedimentation rate (ESR), C-reactive protein (CRP), white blood cell count (WBCC), and the leukocyte adhesiveness/aggregation (LAA) test were determined in each patient. There were 28 subjects in remission and 33 in relapse. Their percentage of aggregated white blood cells in the peripheral blood was 7 +/- 5 and 16 +/- 8, respectively, when compared with the control group (5 +/- 3) (p < 0.0001). Moreover, the LAA test was the only one which could effectively classify patients with IBD into their correct diagnostic categories of remission, mild-moderate, or moderate-severe disease activity. The LAA test is superior to other acute phase reactants used in daily practice to detect the presence of inflammation as well as for the assessment of its severity in adolescent patients with IBD. In addition, our findings may have biological relevance to the disease process and its potential manipulation by anti-adhesive agents.

Adolescent↗

Diurnal variation in serum bilirubin concentrations in infants with neonatal jaundice.

We investigated whether there are independent intradaily changes in bilirubin levels in neonates. Healthy term newborn infants (n = 124) with neonatal jaundice bilirubin >/t171 mmol/L (10mg/dl) were studied for at least 3 consecutive days. Starting from the second day of life, consistent intradaily changes were observed in bilirubin levels (morning levels were greater than evening levels; p < 0.001), and body weight steadily increased. This diurnal variation in bilirubin levels should be considered in the follow-up and treatment of neonatal jaundice.

Bilirubin↗

Portal vein thrombosis caused by protein C and protein S deficiency associated with cytomegalovirus infection.

A 4-month-old girl who was examined because of splenomegaly had portal vein thrombosis, which apparently resulted from a combination of cytomegalovirus infection and deficiency of both protein S and protein C. The cytomegalovirus infection, by damaging endothelial cells, may have triggered a cascade of events that was ultimately expressed as portal vein thrombosis resulting from deficiency of proteins S and C.

Blood Protein Disorders↗

A controlled double blind multicenter study of the effectiveness of 5-aminosalicylic acid in patients with Crohn's disease in remission.

We evaluated the efficacy of an oral formulation of 5-amino-salicylic acid in lowering the relapse rate after remission of Crohn's disease. Included were 59 patients who had proven Crohn's disease of at least 1 year's duration, and who had been in continuous remission for at least 6 months, while taking only 5-aminosalicylic acid or no therapy at all. Remission was defined as a Harvey Bradshaw index score (Softley-Clamp modification) of < 4. Patients were given coded mesalzaine 250 mg or placebo tablets (2 x 2 day). They were seen at 0, 1, and 2 months, and then every 2 months until the end of the study. Trial endpoints were 1 year of follow-up, or clinical relapse results. After randomization, 31 patients were included in the placebo arm, and 28 in the treatment arm. There were no significant differences between the two groups at entry. Ten patients were withdrawn from the trial because of noncompliance, loss of follow-up, or headache. There were more clinical relapses in the placebo arm (15 patients, 55%) than in the treatment arm (6 patients, 27%) (p < 0.05). Mesalazine had a significant advantage over placebo (p < 0.05) only in the subgroups of patients with ileal Crohn's disease and in those older than 30 years. We conclude that mesalazine has a moderate but significant benefit in preventing relapse in Crohn's disease in remission; this occurred only in patients with small-bowel involvement or in those older than 30 years.

Adolescent↗

High Helicobacter pylori numbers are associated with low eradication rate after triple therapy.

This study tested the influence of pretreatment bacterial density on the eradication rate of Helicobacter pylori with triple therapy. One hundred and thirty two patients with endoscopically confirmed H pylori positive, duodenal ulcer or antral gastritis were treated with triple therapy (colloidal bismuth/metronidazole/amoxicillin) for two weeks. Pretreatment urease activity was assessed by the 14C-urea breath test (UBT) in all patients. The mean (SD) pretreatment UBT concentration was similar in patients with duodenal ulcers (318.4 (175.0)) and patients with antral gastritis (288.9 (165.5)). Overall eradication of H pylori was achieved in 85 of 132 patients (64.4%), but was significantly different between patients with high, intermediate, or low pretreatment urease activity (37.5%, 69.5%, and 87.8% respectively). The mean post-treatment UBT value of patients in whom eradication failed was in direct correlation with the pretreatment UBT values. In conclusion, bacterial density, as assessed by urease activity, is an important factor in predicting H pylori eradication. It is suggested that the pretreatment UBT has the potential to identify patients who require modification of the standard therapeutic regimen.

Amoxicillin↗

Increased leucocyte adhesiveness/aggregation is a most useful indicator of disease activity in patients with inflammatory bowel disease.

The aim of the study was to determine the comparative usefulness of inflammatory markers, in evaluating disease activity in patients with inflammatory bowel disease. Disease activity was assessed by the Mayo Clinic score for ulcerative colitis, and Harvey-Bradshaw score for Crohn's disease. Five hundred normal blood donors who had no underlying inflammatory condition served as controls. The erythrocyte sedimentation rate, platelet and white blood cell count, C reactive protein, and the leucocyte adhesiveness/aggregation test (LAAT) were determined in each patient. One hundred and twenty four patients with inflammatory bowel disease were tested while in remission and 128 in relapse. Their mean (SD) per cent of aggregated white blood cells in the peripheral blood was 8 (5) and 17 (10) respectively compared with controls 6 (4) (p < 0.0001). Moreover, the LAAT could effectively discriminate between various grades of disease activity, the values in patients with active disease being 13 (6)% in mild, 17 (10)% in moderate, and 26 (10)% in severe disease (p < 0.0001). Other acute phase reactants including the erythrocyte sedimentation rate, the white blood cell count, the platelet count, neutrophil count, as well as, the C reactive protein concentration did not differentiate as well between the various groups. Using logistic regression analysis to differentiate between inflammatory bowel disease patients in remission or relapse, the LAAT was the single best indicator. The addition of any other test did not contribute to the discrimination. Among the different laboratory variables tested only the LAAT significantly discriminated between the five different subgroups of controls, remission and mild, moderate or severe disease activity.

Adolescent↗

Seasonal variation in the frequency of Helicobacter pylori infection: a possible cause of the seasonal occurrence of peptic ulcer disease.

OBJECTIVES: The seasonal variation of duodenal ulcer disease and its complications have been repeatedly demonstrated in Israel by several independent studies. The aim of this study was to determine possible seasonal variations in the occurrence of H. pylori infection among dyspeptic patients in Israel. METHODS: All 14C-urea breath tests performed in dyspeptic patients at the gastroenterology department in the Tel Aviv Medical Center from January 1991 to December 1992 were reviewed. The monthly variation in the proportion of patients with H. pylori infection was determined, and compared with that of an unrelated 14C-cholyl-glycine breath test. RESULTS: Altogether, 702 patients were examined, and 371 (52.8%) of them were found to be infected with H. pylori. During summer months (July-September), a significant decrease in the percentage of patients infected with H. pylori was found, compared with winter months (December-January, 42.3% vs. 60.9%, p < 0.007). No seasonal variation was found in the results of 14C-cholyl-glycine test. The fluctuations in H. pylori infection were highly correlated with the seasonal occurrence of peptic ulcer disease in Israel. CONCLUSIONS: The frequency of H. pylori infection in dyspeptic patients in Israel is significantly increased during the winter months and decreased in the summer. This seasonal variation is identical to that found in duodenal ulcer disease. Thus, the seasonal variation of peptic ulcer disease could be explained by H. pylori infection, as seen in other communicable infectious diseases.

Breath Tests↗

D-xylose absorption test. Urine or blood?

The D-xylose absorption test has been used during the last four decades for evaluation of malabsorption in the small intestine. However, some disagreement still exists about the recommended method of performing this test: the 1-hr blood test, the 5-hr urine test, or both. We evaluated the test by performing 125 combined blood and urine tests in 111 patients. Normal xylose absorption was recorded in both blood and urine in 71 tests (group A, 56.8%). Abnormal test results in both blood and urine were recorded in 29 patients (group B, 23.2%). Only one patient had a pathological blood value and normal xylose excretion in the urine. Twenty-four patients (group D, 19.2%) had normal 1-hr blood xylose (greater than 25 mg/100 ml) with abnormal 5-hr urine xylose (less than 4.5 g/5 hr). Fat and/or bile salt malabsorption were documented in 21 patients (87.5%) of this group using stool fat analysis and the [14C]cholylglycine breath test. These data suggest that in adults the 5-hr urine collection more accurately reflects intestinal absorption in comparison with the 1-hr blood value.

Adolescent↗

Levels of Cu-Zn and Mn superoxide dismutases in rat liver during development.

Superoxide dismutase is the main scavenger of superoxide radicals in the mammalian body. The liver has high levels of two types of superoxide dismutase enzymes, cytosolic Cu-Zn and mitochondrial Mn enzymes. The aim of the present study was to investigate the content of two distinct superoxide dismutases in liver during the perinatal transition from a hypoxic to a hyperoxic environment. Both isozymes were purified to homogeneity and used as immunogens in rabbits. Antisera raised were found to recognize only polypeptides of molecular weight 16,900 or 23,400, which correspond to Cu-Zn and Mn superoxide dismutases, respectively. It was found that the level of Cu-Zn superoxide dismutase enzymatic activity and protein as assessed by immunoquantitation increased 10-fold during the postnatal period, reaching adult levels by 3 weeks. In contrast, the amount of Mn superoxide dismutase content increased only twofold to adult levels during the first week of life. Neither of the superoxide dismutases showed an alteration in specific activity or apparent molecular weight in rat livers during ontogeny. These results show that the levels of two intracellular superoxide dismutases are differentially elevated during the perinatal period. It is suggested that each dismutase plays a different physiological role for superoxide scavenging in liver as a function of the hypoxic/hyperoxic environment at birth.

Animals↗

Reduced levels of galactose-terminated glycoproteins in rat serum during perinatal development.

Asialoglycoprotein receptor is an abundant protein localized in the sinusoidal domain of the hepatocyte plasma membrane. Its principle function is the clearance of serum glycoproteins which include several acute phase reactant proteins that have lost their terminal sialic acid residue. It has been reported that asialoglycoprotein receptor is nearly absent in mammalian fetal liver but rises to adult levels during the early postpartum period. The hypothesis to be tested was to determine whether defective glycoproteins, those lacking terminal sialic acid residues, are accumulated in fetal serum as a result of reduced receptor content. It was found that low levels of asialoglycoprotein receptor in 18-day-old fetal liver correlated to a threefold higher level of total asialoglycoproteins in fetal serum than adult serum as determined by a modified Western blot protocol employing radioiodinated ricinus communis agglutinin, a galactose-binding lectin. As hepatic asialoglycoprotein receptor accumulated at the time of birth, the elevated level of serum asialoglycoproteins decreased to adult values in an opposite manner. This study indicates that the hepatic asialoglycoprotein receptor plays an important role in reducing the amount of circulating defective glycoproteins at the time of birth.

Animals↗