Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: EC:6.3.4.6 (urease)
 7,490 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The development of a large vaginal stone in a 25-year-old female, correlated with vesicovaginal fistula, is presented. The stone, composited of struvite and carbonate apatite, formed around non-absorbable surgical suturing material in urine with urease producing (P. mirabilis) bacterial infection. The stone was removed by simple lithotripsy technique. Attention is taken for the importance of stone prevention.
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PMID:[Giant secondary vaginal calculus]. 259 61

A case report of vaginal calculus formation in a nine-year-old girl with myelodysplasia is presented. Etiologic factors in the formation of such calculi include fistulous communication between the vagina and the bladder, neuropathic urethrovesical dysfunction, anatomic conditions causing vaginal outlet obstruction, and/or vaginal pooling of urine and urease-producing bacterial infection. A correct preoperative diagnosis can be made by using oblique x-ray films and cystoscopy. Surgical treatment is simple and successful.
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PMID:Vaginal calculus in female with myelodysplasia. 635 34

Hydroxamic acid, a potent urease inhibitor, having a high urinary excretion rate is expected to be a therapeutic agent for urolithiasis caused by urea-splitting bacterial infection of the urinary tract. Twenty-one new derivatives of N-aliphatic-acylglycinohydroxamic acids (GHAs) were synthesized, and their inhibitory potencies against the urease activity of sword bean in a phosphate buffer and against the ureolytic activity of Proteus mirabilis in human urine, and their urinary excretion rates in rats were also measured for this purpose I50 values of most of GHAs against the urease activity of sword bean were about 1 to 10 microM and 2-ethyl-n-butyroyl GHA was the most potent inhibitor with the value of 0.79 microM. I50 values of most of the GHAs against the ureolytic activity of Proteus mirabilis were about 5 to 50 microM and n-nonaroyl GHA was the most potent inhibitor with the value of 3.6 microM. 2,2-Dimethylpropionyl GHA had the highest urinary excretion rate with the recovery of 11%. Routes of administration of 2,2-dimethylpropionyl GHA and sex of rats used did not affect the amount of urinary excretion at all. The results in this report suggest that DL 2-methyl-n-butyroyl, 2-ethyl-n-butyroyl and 2,2-dimethylpropionyl GHA are the most hopeful therapeutic agents for urolithiasis among them.
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PMID:Therapy for urolithiasis by hydroxamic acids. III. Urease inhibitory potency and urinary excretion rate of N-acylglycinohydroxamic acids. 700 14

The effect of bacterial infection on excised renal papillae as a model for papillary necrosis and subsequent calcification was investigated. Sterile rat renal papillae were placed in 25 ml aliquots of filter sterilized human urine and then inoculated with one ml suspensions of sterilized human urine and then inoculated with one ml suspensions of sterile saline as a control, or 1 x 108/ml Escherichia coli or proteus mirabilis. After incubation at 37 degrees C for periods of 8 hr, 24 hr, 48 hr, 72 hr, 1 wk, 2 wk and 3 wk, urinary pH was measured, bacterial culture performed and the renal papillae were recovered and examined by scanning electron microscopy (SEM) and energy dispersive spectrophotometry (EDS). In the case of Proteus mirabilis, the sequence of events noted included bacterial-papillary interactions consisting of cell desquamation and strand formation, despite infrequent bacterial attachment. After 10 hr, a rapid, urease induced pH rise resulted in calcium salt deposition on the papillae surface. Organism death was apparent after 72 hr. Escherichia coli infected papillae demonstrated similar cell surface changes after a 8 hr as seen in P. mirabilis; however, frequent evidence of bacterial attachment and penetration was apparent. Bacterial attachment was a prominent feature throughout the incubation period with E. coli. After one week, rare areas of degenerating cells and bacteria with increased calcium levels as compared to surrounding areas were noted by EDS analysis. Urinary pH was stable throughout the incubation period. This study suggests varied roles for the organisms most associated with infection induced papillary necrosis (E coli) and papillary necrosis with subsequent stone formation (P. mirabilis). A role for bacterial calcification in the absence of bacterial urease activity by E. coli is also suggested.
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PMID:Papillary necrosis in vitro: a scanning electron microscopic comparison of escherichia coli and Proteus mirabilis infection. 703 30

Magnesium ammonium phosphate calculi developed in the urinary bladders and urethras of four of five offspring of Miniature Schnauzer parents with recurrent struvite urolithiasis. Calculi were detected by radiograhy when the dogs were 12 to 15 months old. Males and females were affected. A significant number of urease-producing staphylococci were identified in the urine of three of four dogs before urolith formation, and in one dog after urolith formation. The dogs were evaluated until they were 26 months old. Serum concentrations of calcium, phosphorus, and magnesium were inside usual limits throughout the study. Abnormalities that might predispose to urinary tract infection were not identified by radiography or necropsy studies. In one dog, bladder calculi recurred after surgical removal of multiple cystoliths. In another, urethral obstruction and acute generalized pyelonephritis induced a lethal uremic crisis. Gross and microscopic lesions, detected after necropsy of all dogs with uroliths, were typical of bacterial infection.
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PMID:Struvite urolithiasis in a litter of miniature Schnauzer dogs. 740 90

In a prospective study, thirty consecutive patients presenting with either H.pylori positive (histology and/or culture) ulcer disease (n = 17; acute ulcer: n = 11) or functional dyspepsia (n = 13) were treated over one week with pantoprazole 40 mg bd, clarithromycin 250 mg bd and metronidazole 400 mg bd. Four weeks after discontinuation of the study medication H.pylori eradication was assessed by means of an urease test, culture and histology. One patient had to be withdrawn from the study after one day because of a concomitant infectious disease requiring long-term antibiotic treatment. Another patient refused the final follow-up endoscopy. 28 patients completed the study without contravening the protocol. H.pylori infection was eradicated in 24 out of 28 patients (eradication rate: 86%; 95%-confidence interval: 57%-96%). Cure of bacterial infection was more frequently obtained in ulcer patients as compared to patients suffering from functional dyspepsia (94% vs 75%; p = 0.28). In 2 patients, treatment failure was associated with pretherapeutic resistance of H. pylori to either clarithromycin or metronidazole. Without antiulcer treatment beyond eradication therapy, ulcer healing was endoscopically confirmed after 5 weeks in 9 out of 10 patients available for follow-up (healing rate: 90%; 95%-confidence interval: 56%-100%). Seven patients reported mild adverse events that did not lead to discontinuation of the study medication (rate: 23%; 95%-confidence interval: 10%-42%). After cure of the infection, histology demonstrated a statistically highly significant improvement (p < 0.001) of both grade and activity of antrum and body gastritis.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:[Short-term triple therapy with pantoprazole, clarithromycin and metronidazole in eradication of Helicobacter pylori]. 760 90

Struvite renal stones are caused by infection of the urine with bacteria that synthesize the enzyme urease. Ammonium is released by the breakdown of urea by urease, the urine becomes highly alkaline, and magnesium ammonium phosphate (struvite) and carbonate apatite crystallize. Incorporation of the infecting bacteria within the developing stone, results in a focus of infection that is resistant to conventional antimicrobial therapy, and which is manifested clinically by repeated urinary tract infection caused by persistent bacteriuria. Extracorporeal shock wave lithotripsy (ESWL) currently is accepted as the election treatment for most renal calculi. This trial examines the bacteriologic aspects pre and post-ESWL. Eighty adult patients, 47 females and 33 males, without clinical signs of urinary tract infections (UTI) were submitted to urine cultures pre and post-ESWL. The first 50 patients underwent during and post-ESWL, 150 blood cultures, which all proved to be negative, confirming very low risk of generalized sepsis. No patient presented fever, chills or rigors pre or postprocedures. With respect to urine cultures 43 patients (52.5%) had a pre-ESWL UTI, in comparison to 49 (60%) who had a UTI post-ESWL. The distribution of organisms pre and post-ESWL was as follows: Proteus mirabilis (22/22), Escherichia coli (11/11), Pseudomonas aeruginosa (4/5), Klebsiella pneumoniae (2/2), Enterobacter cloacae (0/1), Alcaligenes odorans (1/2) Enterococcus faecalis (1/3), Staphylococcus saprophyticus (1/2) and Candida albicans (1/1). In this study 6 patients presented bacteriuria post-ESWL probably due to bacteria from inside the calculi. According to these results, the risk of bacteremia seems to be very low. In 60% of staghorn renal stones we could demonstrate a bacterial infection.
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PMID:[Staghorn renal lithiasis treated with shock waves. Bacteriologic aspects]. 765 75

The urinary tract is among the most common sites of bacterial infection and E. coli is by far the most common infecting agent. In patients with urinary catheters in place or structural abnormalities of the urinary tract, Proteus mirabilis is also a frequent isolate. To study virulence of these bacterial species, we have isolated the genes that encode putative virulence factors, constructed specific mutations within these genes, introduced the mutation back into the wild type strain by allelic exchange, and analyzed these mutants for virulence in appropriate in vitro and in vivo models. Specific virulence markers have been identified for strains that cause urinary tract infection. For E. coli, these include P fimbriae, S fimbriae, hemolysin, aerobactin, serum resistance, and a small group of O-serotypes. Redundant virulence factors must be present in these organisms as mutation of the most clearly identified epidemiological marker, P fimbriae, does not result in attenuation of a virulent strain. For P. mirabilis, urease appears to contribute most significantly to virulence. Fimbriae play a significant but more subtle role in colonization. Hemolysin, although potently cytotoxic to renal cells in vitro, does not appear to contribute significantly to the pathogenesis of ascending urinary tract infection. We can conclude that the pathogenesis of urinary tract infection and acute pyelonephritis caused by uropathogenic E. coli and P. mirabilis are multifactorial, as mutation of single genes rarely causes significant attenuation of virulence.
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PMID:Virulence determinants of uropathogenic Escherichia coli and Proteus mirabilis. 786 62

In order to elucidate bacterial infection, as a rule, isolated and cultured bacteria of a specimen are identified by their morphologies or biochemical characteristics. However, the culture of Helicobacter pylori (H. pylori) is difficult and takes, much time. Therefore, favorable test results are currently obtained by combining the culture method, histopathologic method, urease test and sero-immunologic test. The merits of the urease test are that judgement is available immediately after endoscopy and that the test is inexpensive. The demerits are that the existence of H. pylori is diagnosed only by estimation that endoscopy is indispensable for the test. When compared with the culture method, the urease test has 91.8% sensitivity and 94.7% specificity and when compared with the histopathologic method, it has 94.4% sensitivity 88.4% specificity. In the future, the clinical requirement will increase for quick investigation on the evidence of H. pylori-induced infection. These results show that urease test is useful because it is simple and allows quick judgement.
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PMID:[Urease test]. 828 31

Helicobacter pylori infection and adenomatous polyposis coli (Apc) gene mutations have been linked to gastric cancer in humans, but possible synergistic interaction(s) between these risk factors have not been examined. Fourteen C57BL/6 wild-type and 14 Apc1638 heterozygous mice were inoculated with Helicobacter felis at 6 weeks of age and compared at various time points with a similar number of uninfected control mice of the same genotype. Both infected and uninfected Apc1638 mice had a limited incidence of atypical proliferation foci in the mucosa of the antrum and pyloric junction at 4.5 and 6 months of age, whereas polyps of the antrum and pylorus were present in all mice, regardless of infection status, at 7.5 months. In contrast, no altered gastric mucosal foci were observed in control or infected C57BL/6 mice at any time point. Interestingly, the infected Apc1638 mice had less epithelial proliferation and inflammation in the body of the stomach, lower anti-H. felis serum IgG antibody responses (although both the wild-type and Apc mutant mice had a Th1-like immune response, based on a predominantly IgG2a immunoglobulin response), and higher bacteria and urease scores than did infected wild-type C57BL/6 mice. In conclusion, the Apc1638 truncating mutation leads to gastric dysplasia and polyposis of the antrum and pyloric junction, but H. felis infection of the Apc mutant mouse does not lead to an increased rate of gastric neoplasia. In addition, our data suggest this Apc mutation may actually lead to decreased immune, inflammatory, and gastric hyperplastic responses to Helicobacter infection, suggesting the possibility of a novel role for this tumor suppressor gene in the immune and local tissue responses to gastric bacterial infection.
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PMID:Mice carrying a truncated Apc gene have diminished gastric epithelial proliferation, gastric inflammation, and humoral immunity in response to Helicobacter felis infection. 930 81


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