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)

Recent experience with the gastritis-associated organism Campylobacter pylori is reviewed, placing special emphasis on pathologic aspects. C. pylori is a spiral, gram-negative, urease-producing bacillus that has been found to infect the stomach in many people. C. pylori organisms are readily seen overlying the gastric epithelium, often in large numbers. Demonstration in gastric biopsies with silver stains is most vivid, but other faster, simpler stains such as Giemsa, acridine orange, and, at times, hematoxylin-eosin are satisfactory for routine purposes. The frequent occurrence of C. pylori in persons with chronic active gastritis has been confirmed in medical centers around the world. In addition, epidemiological, serological, pathological, and clinical observations suggest that C. pylori infection occurs in stomachs of duodenal ulcer patients with a frequency approaching 100%, and the infection may be relevant to pathogenesis or therapeutic response in duodenal ulcer disease. C. pylori probably also causes an acute infectious gastritis associated with hypochlorhydria. C. pylori still requires extensive investigation to establish its pathogenic role in upper gastrointestinal disorders, but evidence continues to accumulate that such a role exists and that it may be important.
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PMID:Campylobacter pylori: a newly recognized infectious agent in the gastrointestinal tract. 328 85

Forty two patients (20 Fijian and 22 Indian) presenting for endoscopy at the Colonial War Memorial Hospital, Suva, Fiji, were biopsied to detect Campylobacter pylori infection. Detection of the organism's urease activity in biopsy material or seeing the organism in Warthin-Starry silver stained histology sections were used to diagnose infection. Thirty-nine patients (93%) were infected; 19 of 20 Fijians (95%) and 20 of 22 Indians (91%). Of the 39 infected patients, 37 (95%) had chronic active gastritis and 24 (62%) had active peptic ulcer disease. The implications of these findings in relation to the management of endoscopy patients in Fiji are discussed.
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PMID:Campylobacter pylori infection in patients undergoing endoscopy in Fiji. 335 31

Proteus mirabilis, a gram-negative bacillus, is often implicated in the formation of infectious kidney stones. As ureolytic activity of this organism is thought to play a major role in its pathogenesis, we adapted our recently described urease localization technique to visualize urease activity in vivo. Urease activity was ultrastructurally localized in two clinically isolated P. mirabilis strains by precipitating the enzymatic reaction product (ammonia) with sodium tetraphenylboron. Subsequent silver staining of the cells revealed urease activity to be predominantly associated with the periplasm and outer membranes of each strain. Biochemical measurements of urease activity in P. mirabilis cell fractions correlated well with histochemical observations in that the majority of urease activity was associated with the periplasm. Membrane-bound urease activity of these strains was associated mainly with the peptidoglycan in the detergent-insoluble (outer membrane) fraction.
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PMID:Histochemical and biochemical urease localization in the periplasm and outer membrane of two Proteus mirabilis strains. 353 91

We investigated the presence of Campylobacter pylori colonization of the gastric mucosa and of histologic evidence of gastritis in a prospective study of 71 consecutive children undergoing upper gastrointestinal tract endoscopy and gastric biopsies because of gastrointestinal symptoms. Two tissue samples from the gastric antrum were obtained from 67 of the 71 children (mean age [+/- SD], 11.4 +/- 3.8 years). One sample was evaluated for evidence of gastritis and stained with silver to detect organisms morphologically resembling campylobacter. The second sample was cultured for C. pylori, and a portion was used to perform a urease-screening test for the presence of C. pylori. Antral gastritis was diagnosed histologically in 18 of 67 patients. C. pylori was identified by both culture and silver staining on the antral mucosa in 7 of 10 patients with unexplained gastritis (primary gastritis) but in none of 8 patients with gastritis associated with an identifiable underlying cause (secondary gastritis). C. pylori was not identified in any of the 49 cases with normal histologic features. The urease-screening test was positive in only three of six patients with a positive culture for C. pylori. Duodenal ulcers were diagnosed by endoscopy in five patients. Each of the five had C. pylori on the antral mucosa, but organisms were not identified on the duodenal mucosa. We conclude that the presence of C. pylori on the antral mucosa is specifically associated with primary antral gastritis and may also be associated with primary duodenal ulceration.
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PMID:Association of Campylobacter pylori on the gastric mucosa with antral gastritis in children. 358 89

By using nested polymerase chain reaction (PCR) composed of three primers that derived from Helicobacter pylori's (Hp) urease gene region, we have not only successfully amplified control Hp and 214 clinic samples but also studied deeply preparation of the sample, composition of PCR reaction liquid and circulatory mental conditions of the PCR. So this method shortens the operation time, simplifies processes and reduces costs. Compared with urease test (54%) and Warthin-Starry silver stained test (50%), ever used the positive rate of PCR is the highest (61%), so our method is more specific, sensitive, simple, rapid and accurate, and could be applied to the routine clinical detection.
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PMID:[Amplifying Helicobacter pylori's urease gene by nested polymerase chain reaction]. 758 3

Antibodies to H.pylori were investigated in the serum of 50 patients with dyspepsia and 25 healthy controls with ELISA method. The antibody positivity was found in all of the 40 cases (100%) for whom H.pylori was demonstrated in at least two tests of rapid urease, Gram stain, culture and silver staining and in eight of the ten cases (80%) whom H.pylori tests were all negative. Twenty-two of the 25 healthy controls (88%) had also antibodies to H.pylori. The sensitivity of the test was found high (100%), but the specificity was found too low (20%).
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PMID:[Evaluation of the ELISA method for the diagnosis of Helicobacter pylori]. 826 42

On the basis of biochemical, phenotypic, and 16S rRNA analysis, a novel gram-negative bacterium, isolated from normal and diarrheic dogs as well as humans with gastroenteritis, has been recently named Helicobacter canis. A 2-month-old female crossbred puppy was submitted to necropsy with a history of weakness and vomiting for several hours prior to death. The liver had multiple and slightly irregular yellowish foci up to 1.5 cm in diameter. Histologically, the liver parenchyma contained randomly distributed, occasionally coalescing hepatocellular necrosis, often accompanied by large numbers of mononuclear cells and neutrophils. Sections of liver stained by the Warthin-Starry silver impregnation technique revealed spiral- to curve-shaped bacteria predominantly located in bile canaliculi and occasionally in bile ducts. Aerobic culture of liver was negative, whereas small colonies were noted on Campylobacter selective media after 5 days of microaerobic incubation. The bacteria were gram negative and oxidase positive but catalase, urease, and indoxyl acetate negative; nitrate was not reduced to nitrite, and the organism did not hydrolyze hippurate. The bacteria were also resistant to 1.5% bile. Electron microscopy revealed spiral-shaped bacteria with bipolar sheathed flagella. By 16S rRNA analysis, the organism was determined to be H. canis. This is the first observation of H. canis in active hepatitis in a dog and correlates with recent findings of Helicobacter hepaticus- and Helicobacter bilis-related hepatic disease in mice. Further studies are clearly warranted to ascertain whether H. canis-associated hepatitis is more widespread in canines as well as a cause of previously classified idiopathic liver disease in humans.
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PMID:Helicobacter canis isolated from a dog liver with multifocal necrotizing hepatitis. 888 May 4

There were studied 68 patients admitted with clinical signs of chronic gastritis. Biopsies were taken by endoscopical route from the antral and fundic levels in all cases, and paraffin slides were stained with haematoxylin-eosine, modified Giemsa, Warthin-Starry and blue cresyl methods. Microscopical results were compared with those obtained with the urease test performed from the gastric mucus. Results noted the presence of Helicobacter pylori in 41 from 68 cases in the antral mucosa, like curved bacteria located in the mucus on the excretory segment and often on the surface, covering the epithelium. Intracellular Helicobacter pylori was not noted. Its presence is related especially with the active chronic gastritis and rarely with inactive forms; it was not possible to establish a relationship between the morphology, incidence and features of their infiltrate, and the presence of Helicobacter pylori. The modified Giemsa method is easier to perform, faster and cheaper, and it may be currently applied in practice, but from the sensitivity viewpoint, best results have been achieved with Warthin-Starry silver impregnation.
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PMID:Clinical value of Helicobacter pylori identification by histochemical methods in patients with chronic gastritis. 903 95

The goal of this study was to determine whether Helicobacter pylori or similar bacteria are present in the abomasum of cows. The abomasa of 112 clinically healthy cows were examined at slaughter. Prior to macroscopic examination, samples for bacteriological and histological examination were obtained from the fundus and from the pylorus. Bacteriological examination of the abomasal mucosa included the urease test, the microscopic examination of a Gram's stained smear, and culture on various solid media. Samples from the pylorus (63) were more often positive in the urease test than those from the fundus (35). Examination of Gram's stained smears revealed two groups of suspicious microorganisms; spiral-shaped and rod-shaped bacteria, whereby the latter could not be differentiated morphologically from Helicobacter pylori. Spiral-shaped bacteria were more often isolated from the pylorus (101 samples) than from the fundus (30 samples). The bacteria that resembled Helicobacter pylori were found in seven samples from the pylorus and in seven samples from the fundus. Helicobacter pylori was not cultured in any of the abomasal samples. Tissue samples from the fundus and pylorus were stained with hemalum and eosin and with silver according to Warthin-Starry. All but one abomasum had diffuse infiltration of lymphocytes and plasma cells. Lymphocytic follicles were observed in 109 abomasa. Neutrophils were seen in four abomasa, eosinophils in 37 and parasitic lesions in 20. As in the Gram's stained smears, spiral-shaped and rod-shaped bacteria were seen in silver-stained smears. Spiral-shaped bacteria were found in the pylorus of 96 abomasa and in the fundus and pylorus of one abomasum. The rod-shaped bacteria could not be differentiated from Helicobacter pylori by light microscopy. They were seen in glandular lumina of the superficial region of the mucosa in 97 abomasa. They were limited to the pylorus and fundus in 16 and 59 cases, respectively, and occurred in both these areas in 23 cases. The results of this study indicate that spiral-shaped bacteria may be found frequently in the bovine abomasum. Further investigations are required to determine whether these bacteria are associated with the inflammatory lesions that were observed and whether they play a role in the pathogenesis of abomasal ulcers.
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PMID:[The occurrence of spiral-shaped bacteria in the abomasum of cattle]. 948 May 43

The aim of this study is to determine the eradication rate in Helicobacter pylori (Hp) infection using omeprazole 20 mg twice daily, clarithromycin 500 mg twice daily and amoxicillin 1,000 mg twice daily for one or two weeks, in comparison with colloidal bismuth subcitrate 240 mg twice daily, amoxicillin 1,000 mg twice daily and metronidazole 400 mg twice daily for two weeks. 141 patients with Hp associated chronic gastritis or duodenal ulcer were randomly divided into 3 groups. Group I (n = 48) treated with triple therapy of omeprazole, clarithromycin and amoxicillin for 1 week. Group II (n = 47) treated with the same drug and dosage for 2 weeks. Group III (n = 46) treated with triple therapy of colloidal bismuth subcitrate, amoxicillin and metronidazole for 2 weeks. The Hp status was determined by rapid urease test and histology of Warthin-Starry silver stain. The eradication rates of Group I, Group II and Group III were 89.6%, 95.7% and 71.7% respectively. The difference between Group I and Group III, or Group II and Group III was significant. The difference of eradication rate between Group I and Group II was statistically insignificant. The frequency of side effects in Group III was higher than that in Group I or Group II. Although 21.1% of the patients in Group I and II experienced a metallic taste, none discontinued the medication. Our results show that triple therapy with omeprazole, clarithromycin and amoxicillin is an effective and well tolerated treatment for eradication of Hp infection and may be an alternative regimen to the old standard triple therapy.
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PMID:[Omeprazole, clarithromycin and amoxicillin therapy for Helicobacter pylori infection]. 959 3


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