Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0020500 (hyperoxaluria)
 912 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

We prospectively studied 15 infants who, before 3 months of age, underwent resection of the small intestine-proximal in 3 infants, mid in 6, and distal in 6. Two died before one year of age. Many required prolonged parenteral nutrition, but by one year, 12 of the 13 survivors were on oral feedings only, and seven were above the third percentile for height and weight. Developmental delay occurred in the early postoperative period but diminished with time. There was compensatory adaptation of the remaining gut, shown by improving fat and B12 absorption and duodenal bile-salt concentrations. Bacterial contamination complicating end-to-side anastomoses occurred in two cases (P), gastric hyperacidity in four of 12 (1P, 3M), and hyperoxaluria in eight of 14 (1P, 5M, 2D). Studies of immune competence revealed normal cellular immune function (11/11), transient hypogammaglobulinemia (3/14), hypocomplementemia (1/12), and serum autoantibodies (3/10). Thus, massive resection of the small intestine did not preclude spontaneous improvement in absorptive function, growth, and development.
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PMID:A clinical study of young infants after small intestinal resection. 10 3

The effect of calcium concentration (0-10 mmol 1(-1)) on oxalate uptake and transport was investigated in vitro using everted gut segments and sacs. Increase in calcium concentration in the incubation medium led to an increase in the amounts of precipitated oxalate on the intestine; however, the net oxalate flux to the serosal side decreased. The ions, i.e. Ca2+, Ox2-, H2PO4-, HPO4(2-), present in the incubation medium favoured formation of hydroxyapatite and calcium oxalate crystals, as evidenced by Equil II analysis and free energy of the system. The nature of precipitates was confirmed by elemental analysis, X-ray diffraction spectrometry and electron microscopy. Oxalate precipitated on the intestine following incubation with calcium could be released into a calcium- and oxalate-free medium. Animals fed oxalate in the absence and presence of calcium revealed that, during 1 h in the absence of calcium, oxalate moved down the intestinal tract as a distinct peak of greater than 50% (70-90 cm in the intestine), leaving less than 10% in the stomach and first 50 cm of the intestine. In the case of animals fed calcium along with oxalate, 35% of the oxalate was still present in the stomach, and the amounts of oxalate in the intestinal segments gradually increased from 4.5% to 21.7% (0-90 cm) and dropped to 2.1% in the next 20 cm. Since oxalaemia and oxaluria appear to be influenced by intestinal oxalate absorption, the present observations may help to improve understanding of the pathophysiology of disorders exhibiting altered oxalate metabolism.
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PMID:Effect of calcium on oxalate uptake and transport by the rat intestine. 133 82

The study was conducted to investigate the effect of vitamin A, B1 and B6 deficiency on oxalate metabolism in rats. A significant hyperoxaluria was the common observation in all the three vitamin deficiencies (vitamin B6 greater than vitamin A greater than vitamin B1). The activities of hepatic glycolate oxidase and glycolate dehydrogenase were markedly enhanced in vitamin-A- and vitamin-B6-deficient rats. However, lactate dehydrogenase levels remained unaltered in these deficiencies as compared to their respective pair-fed controls. Vitamin B1 deficiency of 4 weeks' duration could augment the activity of glycolate oxidase only, with no alterations in the glycolate dehydrogenase and lactate dehydrogenase levels. Intestinal oxalate uptake studies revealed increased bio-availability of oxalate from the gut in vitamin-A- and vitamin-B6-deficient rats. Thus, the results suggest the relative contribution of both exogenous as well as endogenous oxalate in the process of calculogenesis under various nutritional stress conditions in rat.
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PMID:Comparative studies on the effect of vitamin A, B1 and B6 deficiency on oxalate metabolism in male rats. 236 74

An investigation of variables important to calcium stone formation in urine indicated significantly increased daily excretion of calcium and oxalate and decreased excretion of ascorbate and citrate by recurrent calcium stone formers. In addition, urine volume, sodium, mucopolysaccharide, and protein were also significantly increased. We compared the uptake of citrate and ascorbate from the gut into the blood in normal controls and stone formers. These studies indicated significantly depressed absorption of both these hydroxycarboxylic acids in recurrent calcium stone formers. We also found that concurrent administration of citrate inhibited ascorbate absorption and increased urinary oxalate excretion after an ascorbate load in normal subjects and stone formers. These findings suggest a mechanism that explains hyperoxaluria in stone patients on the basis of a malabsorption of citrate, ascorbate, and possibly other hydroxycarboxylic acids.
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PMID:Chemical factors important to calcium nephrolithiasis: evidence for impaired hydroxycarboxylic acid absorption causing hyperoxaluria. 380 7

The relationships between urinary oxalate, calcium and magnesium were investigated in 81 patients with idiopathic calcium oxalate urolithiasis on their regular diets. A significant relationship was established between calcium and oxalate excretion in the analysis of recurrent stone-formers (n = 44, P less than 0.01), though there was no significant difference between the two in the analysis of the patients overall or in single stone-formers. This suggests that recurrent stone-formers may have some abnormality of oxalate absorption in relation to calcium absorption. The role of calcium-oxalate interaction in the gut as a cause of mild hyperoxaluria is discussed.
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PMID:Comparison of urinary oxalate excretion in urolithiasis patients with and without hypercalciuria. 406 29

The intestinal permeation and 6-hour urinary recovery of small, multisized tracers, polyethyleneglycol 400 (PEG 400), was used to characterize gut permeability in nine patients after bypass surgery for morbid obesity and in ten healthy volunteers. In the patients, who also had hyperoxaluria, the urinary recovery of ingested PEG 400 was lower than in the healthy persons (10.9 and 24.7%). The patients also showed stronger intestinal exclusion of the larger polymers within the PEG 400.
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PMID:Reduced intestinal permeability to low-molecular-weight polyethyleneglycols (PEG 400) in patients with jejunoileal bypass. 651 79

Because of their amphiphilic properties, bile acids have important physiological functions. However, they can also be pathogenetically active. Some recent findings on the biochemistry and enterohepatic circulation of bile acids are presented. In contrast to the adult liver where the only primary bile acids formed are cholic- and chenodeoxycholic acid, the foetal liver is able to synthesise a variety of "atypical" bile acids. Under certain circumstances, a retrograde differentiation is possible in the adult. The very effective transport systems in gut and in the sinusoidal and canalicular membrane of the liver cell limit the bile acids almost exclusively to the enterohepatic circulation. During transport in blood, through biomembranes and in the liver cytosol, bile acids are bound to carrier proteins. The carrier has been detected using photoaffinity labelling. Following biotransformation (sulphation and glucuronidation) pathogenetically active bile acids can be converted into derivatives which can be rapidly eliminated. Disturbances of these mechanisms result in functional defects and diseases. The pathological significance of bile acids in hepato-biliary diseases is represented with regard to the cholestatic and proliferative effect of individual bile acids. The significance of bile acids in chologenic diarrhea, steatorrhea and enteral hyperoxaluria are presented as examples of the pathogenetic effects of bile acids on the gut. In these diseases it is possible to recognise the specific effects of certain bile acids on the colon mucosa. Recent studies have demonstrated that bile acids are possibly of pathogenetic significance in the case of epidemiologically proven relationship between colon carcinoma and high fat, high cholesterol and low fibre diets.
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PMID:[Pathogenic significance of bile acids (author's transl)]. 725 34

Enteric hyperoxaluria complicates extensive disease or resection of the small intestine in the presence of an intact colon, and is associated with calcium oxalate nephrolithiasis. In addition to hyperoxaluria these patients have a low urine volume, low urinary ionic strength and hypocitraturia. Many forms of treatment have been recommended, but none has been subjected to a prospective clinical trial. Mild idiopathic hyperoxaluria is reported in 8-50% of idiopathic calcium oxalate stoneformers. Several pathophysiological mechanisms have been proposed, including low dietary calcium and possible oxalate transport defects in the gut and/or the kidney. Mild hyperoxaluria, or a high oxalate:calcium ratio in the urine, may be particularly important risk factors for calcium oxalate stone formation; an approach to the correction of these abnormalities is proposed.
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PMID:Enteric and mild hyperoxaluria. 778 97

Homeostasis of oxalic acid appears to be regulated, in part, by the gut-associated bacterium Oxalobacter formigenes. The loss of this bacterium from the gut flora is associated with an increased susceptibility to hyperoxaluria, a condition which can lead to the formation of calcium oxalate crystalluria and kidney stones. In order to identify and quantify the presence of O. formigenes in clinical specimens, a quantitative-PCR-based assay system utilizing a competitive DNA template as an internal standard was developed. This quantitative competitive-template PCR test allows for the rapid, highly specific, and reproducible quantification of O. formigenes in fecal samples and provides a prototype for development of DNA-based quantitative assays for enteric bacteria.
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PMID:Direct quantification of the enteric bacterium Oxalobacter formigenes in human fecal samples by quantitative competitive-template PCR. 1020 13

Background: Oxalobacter formigenes is a recently discovered anaerobic bacterium residing in the gastrointestinal tracts of most vertebrates, including humans. Evidence suggests that this bacterium plays an important symbiotic relationship with its hosts by regulating oxalic acid homeostasis. Oxalic acid is a ubiquitous toxic by-product of metabolism associated with numerous pathologic conditions, including hyperoxaluia, cardiac myopathy and conductance disorders, kidney stones, and even death. Despite the potential importance of O. formigenes in several major health disorders, the difficulty in culturing, isolating, and identifying this fastidious anaerobe has limited research of its disease associations. Because O. formigenes must use two unique enzymes to catabolize oxalic acid, this bacterium appeared to be a suitable model for DNA-based identification, thereby circumventing the labor-intensive procedures currently used. Methods and Results: In this study, genus- and group-specific oligonucleotide sequences were designed corresponding to homologous regions residing in the oxc gene that enodes for oxalyl-coenzyme A decarboxylase. A polymerase chain reaction (PCR)-based amplification of the 5'end of this gene directly from genomic DNA isolated from various strains of O. formigenes was used to show that the genus- and group-specific oligonucleotide probes could identify and subgroup the bacterium. Field testing of this PCR-based detection system with 100 fecal cultures collected from children aged 0-12 years demonstrated the ease and efficacy with which O. formigenes can now be identified. Furthermore, these latter data provide a profile for the natural colonization of a human population with this intestinal bacterium. Conclusions: Development and use of this PCR-based detection system permit the rapid identification and classification of the gut-associated bacterium O. formigenes, thereby circumventing the need for the more labor-intensive and lengthy method currently used. The first field test of this detection system indicates that humans apparently do not become colonized with O. formigenes until they begin crawling about in the environment. Furthermore, studies investigating the association between several disorders (eg, kidney stones, irritable bowel syndrome, and hyperoxaluria) and the absence of the bacterium from the gut will now prove far easier.
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PMID:Evaluating Children in the Ukraine for Colonization With the Intestinal Bacterium Oxalobacter formigenes, Using a Polymerase Chain Reaction-based Detection System. 1046 96


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