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Biomedical subjects

R Reifen

Publications and source records attributed to R Reifen.

At least 19 recordsLinked to original sources
PubMed1998

Impaired responses to sweet taste in vitamin A-deficient rats.

In brief-exposure, two-choice preference tests (sucrose solution v water), vitamin A-deficient (VAD) rats exhibited a decreased preference for sucrose relative to control rats. There was no difference in total fluid intake from both choices between the two groups, nor was any significant difference found in circumvallate taste papilla keratin size. It is concluded that the impaired preference for sucrose in VAD rats is due to a specific impairment in taste sensation rather than general malaise.

Animals↗
PubMed1998

Excessive dietary protein and suboptimal caloric intake have a negative effect on the growth of children with chronic renal disease before and during growth hormone therapy.

Although diet and nutrition are an integral part of the management of individuals with chronic renal failure (CRF), little has been written on the effect of nutrition on the growth response to growth hormone (GH) in CRF. We studied the GH axis and nutritional status of 31 prepubertal children aged 8.7 +/- 0.5 years with a height standard deviation score (SDS) of -3.2 +/- 0.2 (mean +/- SEM) with CRF. Sixteen CRF patients on hemodialysis and 15 on peritoneal dialysis were studied. Forty-four age-matched normal short children without GH deficiency served as controls. Spontaneous 12-hour GH and stimulated GH values were significantly higher and GH binding protein (GHBP) was significantly lower in the CRF patients than in the normal short children. Both before the initiation of GH therapy and after the first year of treatment, the growth velocity (SDS) was inversely correlated with dietary protein intake and positively correlated with caloric intake. GH was administered at a dosage of 28 and 21 IU/m2/wk to the CRF group and the normal short children, respectively, divided into seven daily doses. The growth response of the normal short children was significantly greater than that of the CRF patients. GH therapy induced a smaller increment in GHBP and IGF-I in the CRF patients versus the normal short children (8.8 +/- 2.2 and 10.2 +/- 2.7 v 24.8 +/- 1.3 and 27.6 +/- 2.5 nmol/L, respectively, P < .01). The 1-year growth velocity of the CRF children was most closely correlated with dietary protein and caloric intake. The nutritional status of CRF patients is concluded to be a major factor in growth both before and during GH therapy.

Alkaline Phosphatase↗
PubMed1998

Dietary polyunsaturated fatty acids decrease anti-dsDNA and anti-cardiolipin antibodies production in idiotype induced mouse model of systemic lupus erythematosus.

OBJECTIVE: To examine the effect of diets with different polyunsaturated fatty acid contents, including linseed oil which contains 70% omega-3 fatty acids, on autoantibody production in idiotype induced mouse model of systemic lupus erythematosus (SLE). METHODS: Five different fats were fed to mice with induced SLE and antibody titers to anti-DNA and anti-cardiolipin were determined and histological examination of kidneys were carried out. RESULTS: SLE mice fed linseed oil showed lower titers of antibodies to DNA and to cardiolipin and less severe kidney damage than mice fed other diets, including fish oil. CONCLUSION: Use of linseed oil may attenuate the severity of SLE and this diet may be recommended for other auto-immune diseases as well.

Animals↗
PubMed1998

Intestinal and hepatic cell kinetics and mucous changes in vitamin-A-deficient rats.

Changes in tissue histopathology, cell morphology and kinetics and the number of mucus secreting cells were evaluated in the duodenum and colon of normal and vitamin-A-deficient rats. A lower number of goblet cells was detected both in the colon and in the duodenum of vitamin-A-deficient rats in comparison with control rats (p<0.05). vitamin-A deficiency was found to increase the proliferate rate of mucous cells in the duodenum significantly. No significant difference was noted in the proliferate index in the colon specimens in either control group of experimental rats. We suggest that the higher number of proliferating cells in the duodenal crypt and villi in the vitamin-A-deficient animals indicates that vitamin-A deficiency affects the cell proliferation and therefore could be of some importance in understanding the potency of retinoids in differentiation and their association with formation of epithelial metaplasia.

Animals↗
PubMed1998

Transthyretin: a marker for celiac disease activity.

Transthyretin (TTR), a well-established nutritional marker, was measured in patients with active and inactive celiac disease (CD) in order to assess its value as a marker of disease activity. CD activity was assessed by intestinal biopsy to determine intestinal atrophy histologically and by measuring the level of antiendomysial antibody titer. TTR was measured in 26 CD patients fed a diet containing gluten and 22 CD patients fed a gluten-free diet. The control group was composed of 65 healthy sex- and age-matched children. We compared the TTR levels to the two established markers of CD activity. TTR levels were lowest among the celiac patients fed a diet containing gluten and differed significantly from those of the other two groups (r = 0.7, p < 0.002). The TTR levels correlated inversely with both the degree of mucosal atrophy (r = 0.6, p < 0.005) and with anti-endomysial antibody titers (p < 0.005). TTR levels appear to be correlated with morphologic and serologic markers of activity in celiac patients. TTR can be used as a systemic parameter in assessing celiac patients. It can contribute information to the evaluation of children in whom celiac disease is suspected, and it can monitor patients' diet compliance.

Adolescent↗
PubMed1998

Effect of vitamin A on small intestinal brush border enzymes in a rat.

Weanling male rats fed a vitamin A deficient (VAD) diet were compared with rats fed the same diet supplemented with vitamin A. Half of the VAD group was repleted with vitamin A at the age of 70 days. There was a decline in weight in the VAD group after 45 days. Serum and liver retinol concentrations were negligible in the VAD groups at 70 days of age. These levels returned to normal in the repleted group within 20 days of supplementation. Histological observations in the intestinal tissues of the experimental animals exhibited reduced villus height (p < 0.05) compared with the vitamin A supplemented group (VAS), reduced number of mucous secreting goblet cells and total enterocytes. In addition, a significantly higher number of proliferating cells was found along the crypt. Disaccharidases (sucrase and maltase), peptidases (gamma GT) and alkaline phosphatase activities were markedly lower along the brush border (p < 0.05) in the VAD group compared to the VAS group. We also determined the total DNA, RNA and protein in the jejunal tissues per 0.1 mg/tissue in both groups. The RNA production per cell in the VAD groups was notably lower than that of the controls (p < 0.05). Our observation indicates that brush border enzyme levels are altered in animals with vitamin A deficiency, and that phenomenon is augmented when calculated per single cell. This change may be attributed to direct effects of vitamin A on the rate of proliferation and differentiation of the epithelial tissue along the jejunum rather than to gross structural changes along the small intestine.

Alkaline Phosphatase↗
PubMed1998

Vitamin A deficiency induces morphometric changes and decreased functionality in chicken small intestine.

The effect of vitamin A on chicken intestinal mucosal morphology and functionality was tested in relation to severe and mild vitamin A deficiency and vitamin A repletion. Compared with rats and mice, chickens have a very quick response to a deficient dietary intake. Severe vitamin A deficiency altered the small intestine of chickens at both the biochemical and the morphological levels. It caused the loss of mucosal protein, reduced villus height and crypt depth and diminished activities of disaccharidases, transpeptidase and alkaline phosphate (EC 3.1.3.1). The ratios RNA:DNA, RNA:protein and protein:DNA, and the DNA concentrations in 1 g intestinal tissue, together with morphological measurements, provided knowledge about the pattern of lesion. The results indicated that (1) lack of vitamin A influenced cellular hyperplasia as it caused an increase in DNA content and in the number of enterocytes per villus; (2) lack of vitamin A influenced cellular hypertrophy as it decreased the protein:DNA ratio. There was no difference in mucosal enzyme activity between the two deficient groups. The repletion group exhibited a remarkable increase in mucosal enzyme activity only 4 d after switching to the control diet. The evidence presented in our paper suggests that the low vitamin A supply interferes with the normal activity of chicken intestinal mucosa as it influences the processes of proliferation and maturation of enterocytes.

Animals↗
PubMed1997

Serum prolactin in coeliac disease: a marker for disease activity.

Prolactin, a polypeptide hormone of anterior pituitary origin, has pronounced physiological effects on growth, reproduction, and osmoregulation. Increasing evidence indicates that prolactin also has an immunomodulatory influence on the immune system. The status of prolactin in patients with coeliac disease was investigated by obtaining serum samples from 48 patients with active and non-active coeliac disease. These were compared with samples from 20 children with familial Mediterranean fever and 65 normal controls. Serum prolactin in patients with active coeliac disease was significantly higher than in the other groups studied and reference values. Serum prolactin correlated well with the degree of mucosal atrophy and with the serum concentration of antiendomysial antibodies. Prolactin may play a part in immune modulation in the intestinal damage of coeliac disease and serve as a potential marker for disease activity.

Acute Disease↗
PubMed1997

Infection with HIV, syphilis and hepatitis B in Ethiopia: a survey in blood donors.

Sera of all male donors appearing at the blood bank of a regional hospital in Northwest Ethiopia in 1994 (n = 1022) and 1995 (n = 1164), were screened for the presence of human immunodeficiency virus (HIV-1) and treponemal antibodies. Additionally, screening for hepatitis B surface antigen (HBsAg) was carried out on 549 consecutive sera. In 1995, the crude seroprevalence of HIV-1 infection and syphilis was 16.7% and 12.8%. Seroprevalence of HBsAg was 14.4%. HIV and syphilis seroprevalence was highest in soldiers (30.6% and 20.9%) and daily workers (18.8% and 13.5%), and lowest in farmers (8% and 6.7%). However, farmers had the highest rate of HBsAg (18.8%). HIV-positive donors had an increased risk for being positive for syphilis antibodies (OR = 3.69, 95% CI = 2.69-4.96), but not for HBsAg (OR = 0.79, 95% CI = 0.36-1.67). The data indicate that (i) the HIV epidemic has not yet reached a plateau phase in Ethiopia, and (ii) the transmission and epidemiology of HBsAg in Ethiopia is different from that of HIV and syphilis.

Adult↗
PubMed1997

Outcome of hepatobiliary scanning in neonatal hepatitis syndrome.

UNLABELLED: To evaluate the diagnostic information gained from hepatobiliary scanning in infants, we reviewed 86 consecutive infants who were < or = 4 mo old and were treated for conjugated hyperbilirubinemia at the Hospital for Sick Children in Toronto between 1985 and 1993 and who had technetium iminodiacetic hepatobiliary scanning and a percutaneous liver biopsy performed in close temporal proximity. METHODS: Retrospective reviews of hospital charts and blinded reviews of hepatobiliary scans were performed. RESULTS: There were 58 male and 28 female infants (age range, 2-124 days; mean = 65 days). Hepatobiliary scanning failed to show biliary excretion into the gastrointestinal tract in 53 of 86 patients. Forty of these 53 had extrahepatic biliary atresia. The remaining 33 patients demonstrated biliary excretion into the gastrointestinal tract; 24 of 33 had neonatal hepatitis. Among 13 of the 53 patients who had no evidence of biliary excretion and who also did not have extrahepatic biliary atresia, 8 had idiopathic neonatal hepatitis, 4 had interlobular bile duct paucity and 1 had total parenteral nutrition-associated cholestasis. In this large series, no patient with extrahepatic biliary atresia showed bile drainage on hepatobiliary scanning. Fifty percent of patients with interlobular bile duct paucity but no extrahepatic obstruction failed to show biliary excretion of radionuclide. Twenty-five percent of patients (8 of 32) with idiopathic neonatal hepatitis demonstrated no biliary excretion. Hepatocellular extraction was examined by semiquantitative analysis in the nondraining, nonbiliary atresia patients (12 of 53). Four of these 12 patients demonstrated poor liver extraction. Three patients had idiopathic neonatal hepatitis, and one had bile duct paucity. Therefore, four of eight neonatal hepatitis patients had normal extraction, suggesting that poor versus good liver hepatocyte clearance cannot accurately identify neonatal hepatitis. CONCLUSION: Hepatobiliary scanning requires cautious interpretation. Nondraining scans may indicate severe neonatal hepatitis or the presence of interlobular bile duct paucity.

Alagille Syndrome↗
PubMed1996

Incidence of gastroesophageal reflux with whey- and casein-based formulas in infants and in children with severe neurological impairment.

Ten exclusively gastrostomy-fed, neurologically impaired children (4.5-14.5 years old) with gastroesophageal reflux were randomly assigned to receive feedings with either a casein- or a whey-based formula for 48 h each and then crossed over to the other formula. One 24-h pH probe study each was performed while being fed casein- and whey-based formula, respectively. There was a significant reduction in episodes and duration of gastroesophageal reflux while consuming the whey-based formula (p < 0.05). Whey-based feedings should be considered an additional tool in conjunction with other antireflux measures to treat gastroesophageal reflux more effectively in children with severe neurological impairment. A similar study was also conducted involving 14 infants (3-12 months old) with documented gastroesophageal reflux using 24-h pH probe monitoring while consuming a casein-based formula. The formula was changed to a whey-based formula and the pH probe study repeated within 3-5 days. Four infants showed improvement and the rest showed either deterioration (1/14) or comparable results (9/14). The reduction in the mean number of episodes or duration of gastroesophageal reflux with the whey-formula was not significantly different from that with the casein-based formula (p > 0.05). Based on these findings, generalized recommendations for the use of whey-based formula in infants with gastroesophageal reflux cannot be made.

Adolescent↗
PubMed1994

Helicobacter pylori infection in children. Is there specific symptomatology?

Helicobacter pylori is an established cause of chronic-active gastritis in both adults and children. However, it is unclear whether H. pylori causes specific clinical symptoms. Therefore, the spectrum of clinical symptoms associated with H. pylori infection was studied in consecutive symptomatic children undergoing diagnostic endoscopy at two pediatric centers, using a structured questionnaire. In Toronto, Canada, 86 of 97 eligible children were enrolled into the study and in Limerick, Ireland, 24 of 29 were enrolled. The frequency of biopsy-confirmed H. pylori infection in Limerick, 16 of 24 (67%), was fivefold higher than in Toronto, 11 of 86 (13%, P = 0.0001). The two study populations were comparable in clinical presentation and duration of symptomatology and did not differ in age (11.9 +/- 3.5 and 11.6 +/- 2.0 years, respectively). Within both study populations H. pylori infection was not associated with specific clinical symptomatology, including duration of abdominal pain, location of pain, and history of melena or vomiting. H. pylori was positively associated with hematemesis in the Limerick group. These findings demonstrate that H. pylori infection in children is not associated with specific clinical symptomatology across varying geographical locations.

Adolescent↗
PubMed1992

Detection of albumin binding abnormalities in sera of patients with familial dysalbuminaemic hyperthyroxinaemia using isoelectric focusing.

Definitive diagnosis of familial dysalbuminaemic hyperthyroxinaemia (FDH) requires finding a high concentration of [125I]T4 bound to albumin. We used isoelectric focusing (IEF) in agarose gels to study the sera of three members of a family with FDH and compared the distribution of [125I]T4 obtained by IEF with that obtained by conventional agarose gel electrophoresis (AGE). Both IEF and AGE confirmed the diagnoses of FDH. In case #1, the % [125I]T4 bound to albumin was 15.2 and 20.0, with IEF and AGE, respectively, in case #2 23.6 and 26.5, and in case #3, 22.1 and 23.0, compared to normal controls of 5.9 and 7.4, respectively. IEF has not previously been used to diagnose FDH, to our knowledge. IEF has the advantage of eliminating TBG interference with albumin migration, which can potentially complicate the diagnosis of FDH when the AGE method is used. To date, reverse flow electrophoresis, a more cumbersome method with poorer resolution than IEF, has been utilized to eliminate TBG interference. IEF, in agarose gels, is a relatively simple and accurate method to diagnose FDH, and avoids artifacts which may be encountered with AGE.

Adult↗