摘要:

Background:Parenteral administration of iron is a matter of controversy because it is feared that it could contribute to oxidative reactions. The aim of this study was to verify if iron-dextran participates in the redox reactions occurring in total parenteral nutrition (TPN) solutions.Methods:Irondextran was compared with different forms of iron in the interaction with peroxides. Hydroperoxide levels were measured by a colorimetric technique in TPN solutions, in presence of varying sources (FeCl2, FeSO4, irondextran, iron sorbitol) and concentrations (0-0.8 mM) of iron. The consumption and inhibition of peroxide generation were tested by analyzing the effect of iron on different sources of peroxides (H2O2, tert-butyl and cumen hydroperoxide). The free radicals produced under conditions of a Fenton-like reaction were measured by the oxidation of scopoletin. And the proportion of Fe3+freed by both bound-iron sources was counted by measuring the masking effect on the thiol function of cysteine.Results:Free-iron admixture to parenteral nutrition induces the formation of free radicals, whereas sources of bound-iron inhibit the generation of peroxides in parenteral nutrition without implying a Fenton-like reaction.Conclusion:For patients requiring iron supplementation, bound-iron should be added during the preparation of TPN solutions, because it protects against the spontaneous generation of peroxides.

ISSN:0277-2116    

出版商:OVID    

年代:1997

数据来源: OVID

摘要:

Background:The present study was conducted to determine the effects of age and diet (breast milk, milk formula, weaning diet) on the activities of some bacterial enzymes in fecal samples collected from 3- to 24-month-old infants. These bacterial enzymes may generate toxic, mutagenic, or carcinogenic metabolites from plant glycosides (β-glucuronidase, β-glucosidase) or from urea (urease).Methods:The subjects were 68 healthy children ages 3 (n = 20), 6 (n = 20), 12 (n = 17), and 24 (n = 11) months. None of the children had been given any antibiotics during 4 weeks before collection of the fecal samples. Health status, bowel habits, and food consumption of the children were determined by interview of one of the parents using a structured questionnaire. A spot fecal sample from each child was collected.Results:The activities of β-glucuronidase and β-glucosidase increased from 0.52 and 1.17 nmol/min × mg protein (at 3 months) to 1.41 and 2.38 nmol/min × mg protein (at 2 years), respectively. However, at 2 years of age, the children had not yet reached the levels reported in earlier studies on adult populations. Urease activity increased from 4.18 nmol/min × mg protein (at 3 months) to 19.0 nmol/min × mg protein (at 2 years), reaching by 12 months of age the level observed in adults. Breast feeding as such had no consistent effect on fecal bacterial enzyme activities. β-Glucuronidase and β-glucosidase were higher in those 6- and 12-month-old children who consumed more meat, fish, sausages, or eggs.Conclusions:It can be concluded that the fecal enzyme activities in the gastrointestinal tract increase and that their profile changes with age and adoption of adult-type diet. It remains open, however, whether these changes are caused by the normal physiological aging process or by stepwise introduction of new foods to the diet.

ISSN:0277-2116    

出版商:OVID    

年代:1997

数据来源: OVID

ISSN:0277-2116    

出版商:OVID    

年代:1997

数据来源: OVID

摘要:

Background:In 1994, first published reports described cystic fibrosis patients who experienced a then unknown complication-ileocecal and colonic stenoses with submucosal proliferation requiring surgical intervention. To investigate a suspected correlation between increased intestinal wall diameter and high doses of pancreatic enzymes, we carried out a prospective study in our CF-outpatient clinic.Methods:By ultrasound analysis we measured the intestinal wall diameter in 201 patients. One hundred ninety-three patients treated with pancreatic enzymes had pancreatic insufficiency. Eight patients showed normal pancreatic function, seven of them had never been treated with pancreatic enzymes. The control group included 12 healthy children. Measuring points were the distal ileum, cecum, ascending, and descending colon. Measurements were made by the longitudinal and cross sectional cut. The following aspects of the patients' history were recorded (a) current type of pancreatic enzyme medication; (b) total dosage per day (with reference to lipase units); (c) duration of therapy with standard-strength pancreatic enzyme (SSPE) preparations (≤10,000 lipase units per capsule) and HSPE preparations (≥20,000 lipase units per capsule); (d) gastrointestinal complication (distal intestinal obstruction syndrome, meconium ileus, abdominal surgery, intussusception), diabetes mellitus, and hepatobiliary complications.Results:The intestinal wall diamater in patients receiving HSPE therapy was greater (with prominent submucosal layer) than that in patients receiving SSPE therapy or in patients with pancreatic sufficiency. Healthy subjects had the smallest intestinal wall diameter. There was no correlation between patient history and increased intestinal wall thickness.Conclusions:Ultrasound detects characteristic ileocoecal wall lesions in the majority of cystic fibrosis patients on pancreatic enzymes. These lesions may lead to significantly increased ileocoecal wall thickness, which is correlated but not restricted to HSPE.

ISSN:0277-2116    

出版商:OVID    

年代:1997

数据来源: OVID

摘要:

Background:Inborn errors of bile acid synthesis are newly recognized disorders that may cause the phenotypic appearance of neonatal hepatitis or neonatal cholestasis.Methods:This is a clinicopathologic study of two sets of siblings with cholestatic neonatal liver failure.Results:In 3 of the infants, diagnostic evaluation, including analysis of urinary bile salts, revealed a predominance of 7α-hydroxy-3-oxo-4-cholenoic and 7α, 12α-dihydroxy-3-oxo-4-cholenoic acids, a pattern consistent with Δ4-3-oxosteroid 5β-reductase deficiency, which could be primary or secondary. The fourth infant died before such testing could be carried out. In addition, all 4 infants had histologically disseminated hemochromatosis and met diagnostic criteria for neonatal hemochromatosis. In the 3 infants studied, histologic examination of the liver disclosed giant cell hepatitis with extensive loss of hepatic parenchyma and rapid progression to cirrhosis. Early treatment with ursodeoxycholic acid and cholic acid, previously reported as effective therapy, was given to 2 siblings; it failed to reverse or halt the liver damage, and both infants died. One infant, with the original diagnosis of neonatal hemochromatosis, was treated with a variety of antioxidants and chelation therapy, as recently reported. No improvement was demonstrated, and he went on to liver transplantation.Conclusions:The presentation of Δ4-3-oxosteroid 5β-reductase deficiency as neonatal hemochromatosis may represent a distinct subset of this disorder with an accelerated course, no response to therapy and poor prognosis.

ISSN:0277-2116    

出版商:OVID    

年代:1997

数据来源: OVID

摘要:

Background:Certain nutrients and other trophic factors are highly sensitive stimulants of intestinal adaptation following short bowel syndrome. Growth hormone and glutamine in a modified diet have been shown to enhance nutrient absorption in patients with severe short bowel syndrome. However, neither growth hormone nor glutamine is capable of enhancing adaptation in an animal model. This study was conducted to determine if the combination of glutamine and growth hormone could enhance gut adaptation following massive small bowel resection in the rat.Methods:Thirty-four male rats received 70% jejunoileal resections. The first group received glycine and rat growth hormone, the second glutamine and rat growth hormone, and the third glycine but no growth hormone.Results:There was no evidence that the combination of glutamine and growth hormone could enhance mucosal mass, mucosal protein, or mucosal DNA levels relative to the other two control groups of animals. Likewise, sucrase activities were not enhanced by glutamine and growth hormone.Conclusion:It is unlikely that the combination of glutamine and growth hormone will be of benefit in the treatment of patients with short bowel syndrome. The results in previous human studies can be alternatively explained by the long-term nonspecific effect of enteral nutrition on gut adaptation.

ISSN:0277-2116    

出版商:OVID    

年代:1997

数据来源: OVID

摘要:

Background:In mice, immunological adaptation of the gut to microbial and nutritional antigens occurs at weaning in parallel with biochemical and morphological maturation. Because oral administration of spermine to neonatal rats has been shown to induce biochemical and morphological maturation, we investigated whether spermine also affects maturation of the mucosal immune system.Methods:Swiss mice 7, 12, and 27 days old were given spermine orally (0.5 μmol/g body weight) during 3 days. Intestinal length was measured, and lactase and sucrase activities were determined. The phenotype of intraepithelial and lamina propria lymphocytes was assessed by FACS analysis using markers for CD3, TCRαβ, TCRγδ, CD4, CD8α, CD8β, CD5, CD18, CD54, and CD49d.Results:Similar to what occurs during natural development, spermine treatment of neonatal mice increased intestinal length, decreased lactase activity, and increased sucrase activity. The percentage of intraepithelial lymphocytes expressing TCRαβ, CD4, CD5, and CD54, as well as the levels of expression of these antigens, increased after spermine treatment on day 12, similarly to natural maturation. The increase in expression of CD3, TCRγδ, CD18, and CD49d did not reach statistical significance. No effect was observed on CD8 expression. The phenotype of lamina propria lymphocytes was not affected. Spermine administration to 7- and 27-day-old mice had no effect on the phenotype of either intraepithelial or lamina propria lymphocytes.Conclusions:Oral spermine administration to neonatal mice induced, in parallel with biochemical maturation, precocious maturation of the murine intestinal immune system and particularly affected differentiation of the intraepithelial lymphocyte population.

ISSN:0277-2116    

出版商:OVID    

年代:1997

数据来源: OVID

ISSN:0277-2116    

出版商:OVID    

年代:1997

数据来源: OVID

ISSN:0277-2116    

出版商:OVID    

年代:1997

数据来源: OVID

ISSN:0277-2116    

出版商:OVID    

年代:1997

数据来源: OVID