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

Between 1984 and 1986 nineteen patients (20 renal units) were admitted with obstructing uric acid calculi. Seventy-eight percent of all patients with urolithiasis were treated endourologically: 8 kidneys were infected, 8 kidneys were non-functioning and 3 kidneys caused a status colicus. Sodium bicarbonate was used for percutaneous irrigation and all 20 kidneys were cleared within 4 to 18 days. The technique is a valuable adjunct to the ESWL.
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PMID:[Local chemolysis of occluding uric acid calculi]. 323 75

Urease (urea amidohydrolase; EC 3.5.1.5) catalyzes the hydrolysis of urea to yield ammonia and carbamate. The latter compound spontaneously decomposes to yield another molecule of ammonia and carbonic acid. The urease phenotype is widely distributed across the bacterial kingdom, and the gene clusters encoding this enzyme have been cloned from numerous bacterial species. The complete nucleotide sequence, ranging from 5.15 to 6.45 kb, has been determined for five species including Bacillus sp. strain TB-90, Klebsiella aerogenes, Proteus mirabilis, Helicobacter pylori, and Yersinia enterocolitica. Sequences for selected genes have been determined for at least 10 other bacterial species and the jack bean enzyme. Urease synthesis can be nitrogen regulated, urea inducible, or constitutive. The crystal structure of the K. aerogenes enzyme has been determined. When combined with chemical modification studies, biophysical and spectroscopic analyses, site-directed mutagenesis results, and kinetic inhibition experiments, the structure provides important insight into the mechanism of catalysis. Synthesis of active enzyme requires incorporation of both carbon dioxide and nickel ions into the protein. Accessory genes have been shown to be required for activation of urease apoprotein, and roles for the accessory proteins in metallocenter assembly have been proposed. Urease is central to the virulence of P. mirabilis and H. pylori. Urea hydrolysis by P. mirabilis in the urinary tract leads directly to urolithiasis (stone formation) and contributes to the development of acute pyelonephritis. The urease of H. pylori is necessary for colonization of the gastric mucosa in experimental animal models of gastritis and serves as the major antigen and diagnostic marker for gastritis and peptic ulcer disease in humans. In addition, the urease of Y. enterocolitica has been implicated as an arthritogenic factor in the development of infection-induced reactive arthritis. The significant progress in our understanding of the molecular biology of microbial ureases is reviewed.
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PMID:Molecular biology of microbial ureases. 756 14

The aim of the study was to compare the renal citrate excretion and the degree of urine saturation with calcium oxalate in patients with active calcium oxalate urolithiasis and in healthy subjects under basal conditions and after alkalization. There were 20 women before menopause with calcium stone disease aged 33.5 +/- 7.1 in the first group and 20 healthy women aged 32.3 +/- 7.6 in the second one. Sodium bicarbonate was administrated intravenously in a dose 16.8 g during 2 h. 24h excretion of calcium, magnesium and citrate, the degree of urine saturation with calcium oxalate and pH of urine before and after alkalization were evaluated. Hypocitraturia occurred in 45% of patients under basal conditions. The degree of urine saturation with calcium oxalate was significantly higher in women with nephrolithiasis (p < 0.01). A significant increase of citrate excretion (p < 0.001) and a decrease of calcium excretion (p < 0.05) after alkalization took place in both groups. The degree of urine saturation with calcium oxalate decreased significantly in patients with urolithiasis and in healthy subjects. During acute alkalosis, induced by sodium bicarbonate, increase of citrate excretion was observed in patients with urolithiasis in spite of hypocitraturia under basal conditions. This indicates that kidney function following alkalization is normal in "stone kidney". Significantly decreased saturation of urine with calcium oxalate was due to the decrease of calcium excretion and the increase of citrate excretion. In conclusion, the results show that the use of alkalizing factors in prevention of recurrent calcium urolithiasis is justifiable.
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PMID:[Effect of urine alkalization on excretion of renal citrate and degree of urine saturation with calcium oxalate in patients with calcium-oxalate urolithiasis and in healthy subjects]. 800 19

We report a case of bilateral renal calculi in a 1-year-old female with adenine phosphoribosyl transferase (APRT) partial deficiency. She initially visited another institution with high fever as the major complaint. Computed tomography revealed a bilateral renal stone and left hydro nephrosis. In the urine, there were 2, 8-dihydroxyadenine (DHA) crystals. An analysis of the APRT gene revealed the APRT deficiency and the genotype to be APRT*J/APRT*Q0. We performed extracorporeal shock wave lithotripsy (ESWL) under general anesthesia, and as dissolution therapy we administered Meylon through the nephrostomy and citric acid orally. The stone disappeared from her kidney. The analysis of the stone fragments revealed 2,8- dihydroxyadenine (DHA) urolithiasis.
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PMID:[A case of bilateral renal calculi in a 1-year-old female with adenine phosphoribosyl transferase partial deficiency]. 2208 52