Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: UMLS:C0451641 (urolithiasis)
 3,973 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

24-hour urinary citrate excretion was measured in 176 calcium oxalate stone formers and 100 normal controls. A statistically significant difference (p less than 0.03) could be found between the two groups. When stone formers were divided into a group of 69 patients with recurrent calcium urolithiasis (RCU) and a group of 106 patients with a single stone episode, the latter did not differ from the control group, while in RCU a significantly lower citrate excretion compared with controls (p less than 0.005) could be found. Thus, patients with RCU could benefit from alkali citrate prophylaxis. A female-male difference in citrate excretion could not be found in either the control group or stone formers. Recurrent stone formers presented a significantly higher calcium/citrate ratio compared with controls, which would indicate an increased risk for stone formation. The value of routine citrate analysis is limited, however, by the great, variability of citrate levels in stone formers and controls.
 ...
PMID:Value of routine citrate analysis and calcium/citrate ratio in calcium urolithiasis. 202 21

The effects of urinary pH and acid-base balance on the calcium oxalate stone formation was investigated by two experiments. 24-hr urine samples were collected from 15 recurrent CaOx stone formers, 9 single stone formers and 6 age-matched controls. Inhibitory effect of 1% urine in various pH (4.0-9.0) were calculated by a seed crystal method. In the seed crystal system, there were no significant differences in the inhibitory activity of aggregation (Ia) and in the inhibitory activity of size (Is) for each pH of metastable solution between the stone former group and the control group. However, the value of Ia and Is showed a tendency of rise in proportion to a rise in pH. Rats model for calcium oxalate urolithiasis were fed with three different diets (1% NH4Cl, 5% NaHCO3 and 8% NaHCO3 diet) for three weeks. On the fourth week, 24-hr urine samples were collected. In the animal experiment, calcium oxalate stone formations were predominantly recognized in the kidney of the 1% NH4Cl diet group. The biochemical data showed an increase of urinary calcium and oxalate, and a decrease of urinary citrate. These results suggest that low urinary pH and metabolic acidosis are promoters of the calcium oxalate stone formation.
 ...
PMID:[Effects of urinary pH and acid-base balance on the formation of calcium oxalate stone]. 204 98

The low incidence of atherosclerosis and other degenerative diseases including stone disease in the Greenland Eskimo has been attributed to their high consumption of oily fish with its high concentration of eicosapentaenoic acid (EPA). Man cannot synthesis EPA from the precursor essential fatty acid, linolenic acid, and can only assimilate preformed EPA present in fish and fish oil, to bring about a change in the pathway of eicosanoid metabolism from the n-6 to the n-3 series. With a westernised diet the oxygenated products of renal prostaglandin synthesis are metabolites of the n-6 series and these are known to play an important role in several pathophysiological states including stone disease. Our previous studies have shown a relationship between prostaglandin activity and urinary calcium excretion and it would seem that the initiating factor/s for stone formation trigger the mechanisms for prostaglandin synthesis resulting in the biochemical abnormalities associated with stone disease. The Eskimo may be protected from these events by possession of an eicosanoid metabolism that follows an n-3 pathway. To test this hypothesis experiments were performed using an animal model of nephrocalcinosis. The animals were divided into three groups; one group was given an intra-peritoneal injection of 10% calcium gluconate daily for 10 days to induce nephrocalcinosis; a second group was fed MaxEPA fish oil before and during the calcium gluconate injections and a third group only received an intra-peritoneal injection of N saline. A group of 12 recurrent, hypercalciuric/hyperoxaluric stone-formers were treated with fish oil for eight weeks to study the effects on solute excretion. Nephrocalcinosis, which was readily produced in the control animals, was prevented in the experimental animals by pre-treatment with fish oil and urine calcium excretion was significantly reduced. The urinary calcium and oxalate excretion in the recurrent, hypercalciuric stone-formers was significantly reduced with fish oil treatment over an eight week period. There were no untoward side-effects. These studies indicate that the incorporation of EPA in the diet as a substitute metabolic pathway could be a unique way of correcting the biochemical abnormalities of idiopathic urolithiasis.
 ...
PMID:The protective role of eicosapentaenoic acid [EPA] in the pathogenesis of nephrolithiasis. 205 89

A retrospective study of childhood urolithiasis was performed from July 1978 to December 1989 in the National Taiwan University Hospital. During the eleven years, fourteen patients aged from 1 to 16 years were enrolled. The male to female ratio was 10:4, but no sex predilection was found in seven children with bladder stone(s) (M:F = 4:3), Hematuria and pyuria were the commonest symptoms and signs. Bladder stone was the most frequently encountered stone while renal stone was the second. The underlying factors included urinary tract anomalies, and surgical intervention of the urinary tract and trauma. Proteus species was the most common bacterium isolated from the urine of stone patients. However, half of the patients' urine specimens were sterile. Calcium oxalate and struvite were the two main components of the stones irrespective of renal, ureteral, or bladder stone origin. Lithotomy, endourological removal, and extracorporeal shock wave lithotripsy were the major therapeutic procedures, but the last procedure might replace the others.
 ...
PMID:Urolithiasis in children. 206 81

To determine the current status of urolithiasis in 1988, in comparison with that in 1985, we analyzed the 1937 patients of urolithiasis at 17 departments of urology in Mie Prefecture and 2 departments of urology in Wakayama Prefecture. The ratio of male to female patients was 2.6 to 1.0. Geographically, the number of urolithiasis patients was most frequently distributed in Matsusaka City. The frequency of urolithiasis in the urban area was almost the same as that in the rural area. Most of the stones (96.3%) were in the upper urinary tract. The frequency of lower urinary tract calculi tended to be high in southern Mie Prefecture. The ratio of the upper urinary tract calculi to the lower urinary tract calculi in the urban area was higher than in the rural area. The age distribution in males was in the forties, while that in females was in the fifties. The average age was 46.4 years old. The surgical treatment was performed in 671 patients (34.6%) and the extracorporeal shock wave lithotripsy (ESWL) was the most frequent mode of treatment (85.0%), followed by cysto-lithotripsy (4.2%) and percutaneous nephro-uretero-lithotripsy (2.4%). The most frequent component of the urinary tract calculi was calcium oxalate and/or calcium phosphate (81.7%). The stone patient increased in the number during the summer season (July, August and September). In conclusion, in 1988 when the ESWL treatment started in Mie Prefecture, the epidemiologic features of urolithiasis was characterized as follows: the number of patients increased and the broad application of the ESWL treatment resulted in the decreased number of patients with spontaneous discharge and the increased number of patients with recurrent stones and with bilateral or multiple complex stones.
 ...
PMID:[Epidemiologic study on urolithiasis in Mie prefecture. 2. Present status in 1988]. 206 3

It can be difficult to distinguish between primary hyperoxaluria at end-stage renal failure and secondary oxalosis, all the more as primary hyperoxaluria can be latent for a long time and occur at a late stage. A 57 year-old woman, without family nor personal history of urolithiasis, receives regular hemodialysis for a renal failure discovered at end-stage. Eighteen months later, calcium oxalate deposits appear in the skin, bone marrow and both kidneys, suggesting secondary oxalosis. An other 57 year-old woman presents a chronic renal failure due to bilateral urolithiasis, whose surgery has caused a dramatic decrease of renal function requiring regular hemodialysis. Because of apparition of severe bone alterations, a parathyroidectomy is realized, and because of calcium oxalate deposition in the skin and bone marrow, primary hyperoxaluria is suspected. In both observations, the enzyme activity determination in a liver biopsy gives the diagnosis of primary hyperoxaluria.
 ...
PMID:[Adult type I primary hyperoxaluria: 2 cases confirmed by liver biopsy at end-stage renal insufficiency]. 207 21

Nephrolithiasis and endemic renal distal tubular acidosis are common in northeastern Thailand. The etiology is still unknown. It is generally accepted that urine electrolytes influence the capacity of urine to inhibit or promote renal and also bladder stones. The purpose of this study was to analyse the composition of the urine in the indigenous population in the northeast area and compare their values with data obtained from a group of age matched adults, living in Bangkok. Twenty-four hour urine samples from 23 normal adult villagers from six villages within the province of Khon Kaen and 34 normal adults living in Bangkok were collected, and the daily excretion of creatinine, uric acid, calcium and inorganic phosphate, sodium, potassium, chloride, magnesium and oxalate were assayed. Daily urinary sodium, potassium, chloride and phosphate of the villagers were significantly lower than those of Bangkokians. No difference in the urinary excretion of calcium, magnesium, uric acid, oxalate and creatinine was found. The Na/Ca, and Ca/PO4 ratios of villagers were significantly lower than those of the Bangkok subjects. The villagers excreted significantly lower amounts of Na in the face of relatively higher urinary Ca. The above data, combined with our previous study showing the low values of urinary citrate in the villagers in the same areas, strongly indicate that the indigeneous population is at high risk in developing urolithiasis. The causes for these electrolyte abnormalities are still unknown. Low contents of the major electrolytes in their diets might play an important role. Low phosphate output indicates low protein diets.(ABSTRACT TRUNCATED AT 250 WORDS)
 ...
PMID:Urinary constituents in an endemic area of stones and renal tubular acidosis in northeastern Thailand. 207 84

Approximately 70% of patients who form metabolic stones have the idiopathic calcium oxalate urolithiasis syndrome, which is diagnosed by exclusion of other identifiable metabolic abnormalities. This article reviews the classification, risk factors, and treatment options for those patients with this syndrome.
 ...
PMID:Idiopathic calcium oxalate urolithiasis. 208 20

Attachment of microcrystals to cellular membranes may be an important component in the pathophysiology of urolithiasis. This study characterizes the concentration-dependent binding of uric acid crystals to rat renal inner medullary collecting duct cells in primary culture. Collecting duct cell cultures grew as monolayers with interspersed aggregates of rounded cells. Cultures were incubated with 14C-uric acid crystals, and the crystals that bound were quantitated by adherent radioactivity. Uric acid crystal adherence demonstrated concentration dependent saturation with a 1/alpha value (maximum micrograms of crystals adhering to 1 cm2 of binding area) of 645 micrograms/cm2. The beta values (fraction of cross-sectional area which bound crystals) of uric acid (mean = 0.15) and calcium oxalate monohydrate (mean = 0.13) crystals did not differ significantly. Uric acid crystal binding was inhibited by pre-bound calcium oxalate monohydrate crystals in a concentration dependent manner. These data suggest that uric acid and calcium oxalate crystals exhibit similar binding patterns to rat renal inner medullary collecting duct cells in primary culture.
 ...
PMID:Uric acid crystal binding to renal inner medullary collecting duct cells in primary culture. 210 62

The authors studied the features of urolithiasis in three different geographical regions: Moscow, the Kirghiz SSR, and Berlin from the findings of examination of the composition and structure of uroliths removed by operation or passed spontaneously, (602 concrements from Moscow, 10,000 from Berlin, and 127 from Kirghizia). X-ray diffraction measurement, infrared spectrophotometry, and polarizing microscopy were conducted to analyze the composition and structure of the stones. Complex biochemical examination was carried out in patients from Moscow and Kirghizia. According to the results of the study, the following features of urolithiasis are common in the studied regions: (1) prevalence of oxalate lithiasis on the whole, which points to the principal role of metabolic factors in lithogenesis; (2) approximately similar amounts of apatite carbonate crystals in the uroliths; (3) certain similarity in composition of concrements from Berlin and Kirghizia. The most essential differences are: (1) the frequency of renal oxalate stones is highest in Berlin and lowest in Moscow. The prevalent types of calcium oxalate stones are: whewellite of concentric structure (linked with hyperuricemia) in Kirghizia; whewellite of small randomly orientated crystals (linked with hypercalciuria) and stones with signs of transformation of weddellite to whewellite in Moscow; (2) lesser distribution of phosphate lithiasis in Berlin than in Kirghizia and particularly in Moscow. Prevalence of struvite crystals in stones from Moscow, the formation of which is linked with the vital activity of Proteus and E. coli; (3) higher distribution of urate lithiasis in Moscow and particularly in Kirghizia where significant metabolic risk factors of lithogenesis were revealed.
 ...
PMID:[The characteristics of the chemical composition and structure of urinary stones and their prevalence in the cities of Moscow, Berlin and of the Kirghiz SSR]. 214 36


<< Previous 1 2 3 4 5 6 7 8 9 10 Next >>