Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: UMLS:C0020438 (hypercalciuria)
 2,502 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Oxalic acid seems to play a far greater role in the formation of calcium oxalate stone than calcium. Three grams of calcium lactate and 3 g of sodium potassium citrate were administered to 46 urolithiasis patients, whose stones were mainly composed of calcium oxalate. Urinary oxalate level was reduced significantly without raising urinary calcium level by the administration of the two drugs for two weeks. The reduction of urinary oxalic acid was particularly remarkable in patients without hypercalciuria. The mechanism of action of these drugs was discussed.
 ...
PMID:Reduction of urinary oxalate by combined calcium and citrate administration without increase in urinary calcium oxalate stone formers. 154 Oct 59

The synergistic interaction of fructose and magnesium (Mg) deficiency on kidney calcification was compared in male and female rats. Male and female weanling rats were divided into four dietary groups: fructose or starch, with or without Mg. Rats were fed their respective diets for 9 weeks, and 24 h urine was collected to measure urinary output, pH, Mg, calcium (Ca), and oxalic acid. Rats were fasted overnight. After decapitation, blood was collected immediately, and kidneys were removed to determine their Mg and Ca content. Dietary fructose significantly increased kidney Ca in female rats fed deficient or adequate Mg diet and in male rats fed Mg-deficient diet only; the greatest kidney calcification occurred in female rats fed Mg-deficient diet (P less than 0.0001). Even in starch groups female rats fed the Mg-deficient diet showed some kidney Ca accumulation. The synergistic interaction of fructose and magnesium deficiency on nephrocalcinosis was significantly greater in female than in male rats. Low urinary output, optimal pH 6.8 for calcium phosphate precipitation, hypercalcaemia, hypercalciuria, hypomagnesuria, and low ratio of urinary Mg to Ca may independently or multifactorially contribute to nephrocalcinosis. The possible mechanism of this interaction is discussed.
 ...
PMID:Dietary fructose produces greater nephrocalcinosis in female than in male magnesium-deficient rats. 191 Oct 97

With the development of extracorporeal shock wave lithotripsy treatment, the duration of hospitalization for stone patients fortunately has become shorter. However, a detailed analysis of lithogenesis is not possible during such patients' short hospital stays. We prepared a standard diet to be eaten at home for investigation of lithogenesis at the out-patient clinic. This diet was nutritionally well-balanced and contained the following: energy: 2000 Kcal, total protein: 70-75 g, animal protein: 30-35 g, carbohydrate: 510 g, fat and oil: 50-60 g, calcium: 600-630 mg and magnesium: 320 mg. The urine of 24 male patients with stones on a free diet and the same patients after 3 days on the standard diet was analyzed for urea-nitrogen, uric acid, sodium, calcium, phosphorus, magnesium, citric acid and oxalic acid. The results were compared with those in 17 healthy male subjects who were eating the standard diet (controls). It was found that 66% of hypercalciuria (greater than = 300 mg/day) on a free diet became normocalciuria on the standard diet. The hypercalciuria was therefore thought to be of dietary origin. Moreover, urinary excretion of urea nitrogen, uric acid, sodium and phosphorus by patients remarkably decreased after 3 days on the standard diet, which was not different from that of controls. These results suggest that the standard diet at home is useful in the screening of hypercalciuria and also quite adequate for patients with stones.
 ...
PMID:[Preparation of a standard diet for out-patients in the study of lithogenesis]. 207 1

Oxalic acid seems to be more important for the formation of calcium oxalate stone than calcium. Three grams of calcium lactate and 3 g of uraly U were administered to 35 urolithiasis patients, whose stones were mainly composed of calcium oxalate. Urinary oxalate level was reduced significantly without raising urinary calcium level by the administration of the two drugs for two weeks. The reduction of oxalic acid was particularly remarkable in patients without hypercalciuria. The mechanism of action of these drugs and the relation to dietary management were discussed.
 ...
PMID:[Reduction of urinary oxalate excretion by administration of calcium and citrate]. 260 Dec 15

Twenty-four-hour urinary excretion of calcium, oxalic acid, inorganic phosphorus, magnesium and citric acid was examined in fifty-nine stone formers with bladder stones. Hypercalciuria and hyperoxaluria were present in 18.6% and 44.1%, respectively, while 11.9% of patients had both abnormalities. Hypomagnesuria and hypocitraturia were present in 67.8% and 69.5%, respectively, while 45.7% had both of these abnormalities. Normal urine chemistry in respect of parameters studied was observed only in 1.7% of cases. In 15.2% one risk factor was present, while 83.1% had two or more risk factors. "Path" analysis of the urinary parameters directly related to calcium lithiasis showed that magnesium and oxalic acid have substantial influence on calcium excretion, whereas citric acid had none. The influence of phosphorus did not provide any consistent trend.
 ...
PMID:Interdependence of urinary factors in calcareous bladder stone patients. 274 86

In the present study Farnolith (a granular powder consisting of different dietary fibres) was given to normals (n = 6), patients suffering from absorptive hypercalciuria type I (n = 6) and to one patient suffering from renal hypercalciuria. Farnolith binds calcium and reduces the calcium absorption from the intestine. In normals the urine- and serum parameters of calcium metabolism (total- and ionised calcium, parathyroid hormone and vitamin-D-metabolites) remained unchanged. In patients suffering from absorptive hypercalciuria type I a significant reduction of hypercalciuria was found; oxalic acid excretion had decreased as well. Lowered parathyroid hormone values returned to normal, vitamin-D-metabolites remained unaffected. In one patient suffering from renal hypercalciuria parathyroid hormone and 1,25-dihydroxy-vitamin D values increased, calcium excretion had not decreased, though. Our investigation shows that Farnolith is suitable for the treatment of absorptive hypercalciuria. Calcium homoeostasis is returned to normal by Farnolith, at the same time it does not produce secondary hyperoxaluria (as e.g. sodium cellulose phosphate). Patients with primary renal calcium loss should not be treated by Farnolith.
 ...
PMID:Calcium metabolism in normal and in hypercalciuric patients on Farnolith, a dietary fibre preparation. 285 67

An assay system for the measurement of the rate of Calcium Oxalate Monohydrate (COM) seed crystal growth in a metastable solution of calcium chloride and sodium oxalate containing traces of 14C-oxalic acid was used to assess the inhibitory activity of pyrophosphate (10(-5) M-10(-4) M), citrate (10(-4) M-10(-3) M) and urines of normal and pyridoxine deficient rats. Both pyrophosphate and citrate were strong inhibitors of COM crystal growth and caused a 50% decrease in crystal growth rate at 1.50 X 10(-5) M and 2.85 X 10(-4) M respectively. Normal rat urine strongly inhibited the COM crystal growth, while pyridoxine deficient animals showed a significant (p less than 0.01) decrease in mean inhibitory activity as compared to pair-fed controls. A lowered urinary inhibitory potential accompanied with hyperoxaluria and hypercalciuria, which is known to be associated with pyridoxine deficiency, may be a contributory risk of calcium oxalate crystallization and stone formation.
 ...
PMID:Inhibition of calcium oxalate monohydrate (COM) crystal growth by pyrophosphate, citrate and rat urine. 302 39

Cocoa is a strong carrier of oxalic acid (average: 400 mg per 100 g). In three calcium oxalate stone formers clinical observation had been suggestive of excessive intake of cocoa products contributing to calculus formation. We studied the effect on renal oxalate excretion of an oral cocoa load (30 g per m2 body surface given on 2 consecutive days) in 12 former stone formers (group 1), 14 children with isolated microscopic haematuria (group 2), 13 healthy boys (group 3), and 12 healthy girls (group 4). A new enzymatic method was used to measure oxalic acid in cocoa products as well as in urine samples by a two step reaction: 1. Oxalate decarboxylase, 2. formiate dehydrogenase with photometry of NADH. In addition, the daily excretion of the following substances was measured: Citrate, magnesium, and calcium. There was a significant increase of urinary oxalate excretion from an average of 14.5 mg/24 hours before to an average of 22.2 mg/24 hours after the load in healthy children, and a similar increase in stone formers, but not in children with microscopic haematuria. The excretion of citrate and magnesium did not change following cocoa intake. The calcium excretion was higher in stone formers than in the other groups, but the difference was significant only compared to group 2. It is concluded that the risk of calculus formation may increase following continuous and excessive intake of cocoa products in children with a tendency toward hypercalciuria. Counselling of the stone formers resulted in a marked drop of the daily oxalate excretion, and there was no recurrence of calculus formation over a period of 6 years.(ABSTRACT TRUNCATED AT 250 WORDS)
 ...
PMID:[Effect of cocoa on excretion of oxalate, citrate, magnesium and calcium in the urine of children]. 406 17

Calcium and oxalate were studied in daily, fasting and postprandial urine specimens from healthy subjects and patients with idiopathic renal calcium stones in response to a test meal free of oxalate, and supplemented with calcium and 14carbon-oxalic acid. The data showed that the amount of oxalate in fasting urine of patients with stones did not differ from that in controls. Generally, patients with stones had considerable postprandial hyperoxaluria in terms of excretion and concentration, associated with a significantly higher degree of supersaturation with regard to calcium oxalate compared to controls. These findings were paralleled by decreased intestinal absorption of 14carbon-oxalate and by unchanged 24-hour urinary oxalate. Although the source of increased postprandial oxalate in patients with stones is not clear the possibility of enhanced de novo synthesis from oxalate precursors is discussed. In patients with different types of calciuria the 2 main risk factors (hyperoxaluria and hypercalciuria) for the process of stone formation are recognizable more readily in the postprandial urine specimens than in fasting or daily urine specimens.
 ...
PMID:Postprandial hyperoxaluria and intestinal oxalate absorption in idiopathic renal stone disease. 647 Dec 6

Clinical and biochemical data were obtained from 50 patients in whom stones form and 20 controls to set up and test a screening procedure for detecting metabolic abnormalities related to the formation of urinary calculi and to provide a preliminary estimate of the frequency of these disorders in our area. A comparison between patients in whom stones form and controls in terms of the quantitative biochemical parameters evaluated (serum calcium, uric acid and inorganic phosphate, and urine calcium, uric acid, inorganic phosphate, oxalic acid, xanthine and alpha-amino-nitrogen) showed a significant difference only with respect to excretion of urinary oxalate by adults, which was higher in patients in whom stones form. Metabolic disorders were detected in 15 adult patients with stones. Of these patients 9 had isolated hyperoxaluria, 3 had incomplete renal tubular acidosis, 1 had idiopathic hypercalciuria, 1 had heterozygous cystinuria and 1 had idiopathic hypercalciuria associated with heterozygous cystinuria. These results suggest a high frequency of metabolic abnormalities in patients in whom stones form in our area, so that the wider use of the screening used here may benefit a large number of patients with preventive and therapeutic measures.
 ...
PMID:Metabolic factors in urolithiasis: a study in Brazil. 742 May 93


1 2 Next >>