Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts: Gene/Protein Disease Symptom Drug Enzyme Compound   Target Concepts: Gene/Protein Disease Symptom Drug Enzyme Compound

---

Query: EC:6.3.4.6 (urease)
7,490 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

To determine the prevalence and significance of Helicobacter pylori (H. pylori) infection, biopsies of the antral mucosa were obtained from 139 patients and 43 asymptomatic volunteers. The specimens were examined by hematoxylin-eosin staining and the ureas test. The detection rate of H. pylori by histologic examination was 91.3% in patients with duodenal ulcer, 75.0% in those with combined duodenal and gastric ulcer, 63.6% in those with gastric ulcer, 22.9% in those with gastric carcinoma, 36.4% in those with gastric adenoma, 14.3% in those with gastric hyperplastic polyp, and 51.7% in those with gastritis, and the respective percentages detected by the urease test were 91.3%, 75.0%, 54.5%, 28.6%, 27.3%, 14.3%, and 44.8%. H. pylori was also detected in 10/43 (23.3%) asymptomatic healthy volunteers by histology and the urease test. The prevalence of H. pylori was significantly higher in the patients than in the asymptomatic healthy volunteers (p < 0.05). H. pylori was detected in 62.9% of patients with endoscopic erosive gastritis and in 97.9% of those with histologically proven chronic active gastritis. The urease test was positive in 77/82 patients who were histologically positive for the organism (sensitivity: 93.9%), and it was negative in 98/100 patients who were negative by histology (specificity: 98.0%). Thus, there was over 90% agreement between the urease test and histology. Our investigations showed that H. pylori was closely related to peptic ulcers and antral gastritis, and that the urease test provides a simple, rapid and accurate diagnosis of H. pylori infection.
...
PMID:Helicobacter pylori infection and gastroduodenal disease: a comparison of endoscopic findings, histology, and urease test data. 129 70

1. The accuracy of an indirect immunofluorescence (IIF) test for the serodiagnosis of Helicobacter pylori infection was evaluated in adult patients and compared with culture, preformed urease test and smears stained with carbolfuchsin. 2. We studied 80 consecutive patients submitted to gastroduodenoscopy (17 of whom were found to have duodenal ulcer) plus 57 patients with duodenal ulcer. 3. H. pylori was identified by microbiological methods in 65 of the 80 consecutive patients and in all 57 patients with duodenal ulcer. 4. Among the 74 patients with duodenal ulcer, 71 presented antibody titers > or = 1:20 and 46 of the 48 H. pylori-positive patients without duodenal ulcer presented antibody titers > or = 1:20. 5. Thirteen of the 15 H. pylori-negative patients presented antibody titers < or = 1:10. 6. The sensitivity, specificity and positive predictive value of the IIF test were 95.9%, 88.8% and 98.4%, respectively. 7. The seroprevalence of H. pylori in 380 asymptomatic Brazilian blood donors was also studied by the IIF test. The presence of IgG antibodies against H. pylori was observed in 62.1% of the individuals. The prevalence of H. pylori infection increased with age and no difference was observed between males (60.3%) and females (66.6%).
...
PMID:Indirect immunofluorescence determination of the frequency of anti-H. pylori antibodies in Brazilian blood donors. 134 99

Hp now appears to be more than a simple commensal organism in patients with gastritis or peptic ulcer disease. Microbiologic, serologic, and epidemiologic studies all confirm that Hp has an important role in children with abdominal pain. Hp is found in the gastric mucosa of children with histologically proven gastritis or peptic ulcer. The organism can be transmitted from human to human with evidence of colonization, appearance of gastritis, and serum antibody response. Antimicrobial therapy directed at Hp eradicates colonization and resolves symptoms. Hp antibodies appear more frequently in familial clusters and the frequency of antibody positivity increases with age. Children are more likely to have symptomatic disease associated with elevated antibody titers. Recurrence of disease is associated with reappearance of the organism. At the present time, colonization can be detected only by gastric biopsy; however, it may be possible eventually to diagnose or follow infections by obtaining serum antibody titers or urea breath-testing. The natural history of Hp infection is unclear. Although it can cause an acute gastritis, it generally is found in association with chronic gastritis. The increase in seropositivity with age may mean that slow changes evolve over decades or that age cohorts have been infected differentially. How does antral colonization with Hp cause duodenal ulceration? The organism is not found in the duodenum and most patients with gastritis do not develop ulcers. This may be related to changes in acid production and mucosal protection associated with Hp colonization, but few studies have been done. What factors initiate Hp infection? Both volunteers who became colonized first suppressed acid secretion with H2-antagonists. Hypochlorhydria also seems to follow Hp infection in these same studies. The role of diet and drugs, or other environmental and genetic factors, in initiating infection is largely unexplored. An effective means of therapy needs to be developed. Although Hp appears sensitive in vitro to many compounds, it is difficult to eradicate in vivo, especially with monotherapy. Single-drug therapy suppresses the organism, but recurrence rates are high. It is difficult to deliver effective doses of drugs to the mucous niche the organism has selected and concerns about long-term therapy and its side effects persist. Current data suggest no ready solution to the initial case presentation. A child with primary gastritis or duodenal ulcer should be treated first with standard antacid and H2-receptor antagonist therapy. If endoscopy is performed, biopsies of normal-appearing areas of gastric antrum should be stained for Hp and a biopsy urease test should be performed.(ABSTRACT TRUNCATED AT 400 WORDS)
...
PMID:Helicobacter pylori, gastritis, and ulcers in pediatrics. 144 15

The rise in serum gastrin and pepsinogen I after 5 days' treatment with the proton pump inhibitor pantoprazole (40 mg/day) was examined in eight duodenal ulcer patients with Helicobacter pylori infection and compared with eight in whom it had been eradicated. Before treatment, the post-prandial serum gastrin concentrations were higher in the H. pylori-positive than -eradicated patients (p less than 0.05). The median rise in pre-prandial serum gastrin concentrations on treatment was similar in the H. pylori-positive (41%) and -eradicated patients (45%). The rise in post-prandial serum gastrin was also similar in the H. pylori-positive (81%) and -eradicated patients (69%), resulting in significantly higher gastrin concentrations during treatment in the former. The median rise in serum pepsinogen I on treatment was greater in the H. pylori-positive (114%) than in the -eradicated patients (8%), resulting in significantly higher concentrations during treatment in the former. These observations indicate that eradication of H. pylori may be a means of moderating the hypergastrinaemia caused by acid-inhibitory therapy. They also indicate that H. pylori-related hypergastrinaemia is not due to an increase of the antral surface pH by the bacterium's urease activity.
...
PMID:Helicobacter pylori and hypergastrinaemia during proton pump inhibitor therapy. 153 64

Helicobacter pylori infection is now recognized as the primary cause of active chronic gastritis in humans. Most infected persons remain asymptomatic, but are at increased risk for the development of peptic ulcer disease and possibly gastric cancer. The pathogenesis of this infection is not well understood, but motility and urease activity are virulence factors in an animal model. The eradication of H. pylori infection is associated with resolution of gastritis and a decreased rate of duodenal ulcer recurrence.
...
PMID:Helicobacter pylori and gastroduodenal disease. 158 May 78

The variation in the healing and the relapse rates of peptic ulcer disease has led to the search for other factors in the pathogensis of peptic ulcer disease. Helicobacter pylori is believed to be responsible for these different patterns of healing. The results of a study to detect Helicobacter pylori in Sri Lankan patients having duodenal ulcer, gastric ulcer, gastritis and non-ulcer dyspepsia are presented in this paper. The method employed was the urease test which detects the urease enzyme of H. pylori in gastric mucosal biopsies taken during upper gastrointestinal endoscopy. There is a high incidence in those with gastritis and duodenitis.
...
PMID:Helicobacter pylori and peptic ulcer disease in Sri Lanka. 158 90

A total of 160 adult Malawians with epigastric pain for longer than 2 weeks was investigated by endoscopy and serologically for evidence of infection with Helicobacter pylori. The organism was demonstrated histologically and/or by culture in 141 (88%) patients. With histological means and/or culture as the 'gold standard', the histological technique was 100% sensitive while culture was only 81% sensitive. All isolates tested were sensitive to amoxycillin and tetracycline; 74% were resistant to metronidazole. Endoscopic findings were normal in 104 (65%) patients (86.5% H. pylori positive). Evidence of duodenal ulcer was found in 41 (25%) patients (95% H. pylori positive). Histologically, gastritis was common, severe gastritis being associated with increased colonisation by H. pylori. Two kinds of urease test were found to be 100% specific for the presence of H. pylori. The sensitivity of the serological test (Helico-G test) was 98% but its specificity was only 27%. These results provide important background information for planned therapeutic studies in patients with upper gastro-intestinal disease in Malawi.
...
PMID:Helicobacter pyrlori in Malawi, central Africa. 160 48

Cytology and the rapid urease test on gastric biopsies may diagnose Helicobacter pylori (H. pylori) infection within an hour. We evaluated the sensitivity and reproducibility of touch cytology (imprints from biopsies). In 19 patients with duodenal ulcer, biopsies were obtained from the antrum, fundus, and bulb. H. pylori was diagnosed in 42 sites on smears: 28 by culture and 23 by histology. H. pylori was present in the antrum and fundus in 16 and in the bulb in 11. Assessment of paired antral biopsies in 29 additional patients with or without touch cytology (imprints) before specimens were sent for histology or culture revealed no difference for the presence of H. pylori. A second reading of the 58 smears by a second observer revealed agreement on the presence or absence of H. pylori in 53 (91%). In conclusion, touch cytology is a simple rapid, sensitive, and reproducible diagnostic method for H. pylori that does not alter the quality of biopsies for subsequent culture or histologic examination. For the first time, diagnostic methods have been compared on the same biopsies, eliminating sampling variation.
...
PMID:Cytology: a simple, rapid, sensitive method in the diagnosis of Helicobacter pylori. 172 19

The purpose of the communication is to review the different aspects of the Helicobacter (Campylobacter) pylori infection. The first part of the communication is devoted to the description of the different gastric pathologies induced by the Helicobacter pylori infection and to the different methods used for the detection of this infection. Today a consensus assesses a causal role to Helicobacter pylori in the development of chronic active gastritis (or type B gastritis), in the pathogenesis of duodenal ulcer, and a major contributing factor in the development of peptic ulcer disease. The possible role played by this bacterium in the development of non-ulcer dyspepsia is still unclear. H. pylori infections can be detected using different methods including invasive methods--requiring an endoscopy (e.g.: culture of the micro-organism, urease test, microscopy) and non-invasive methods (e.g.: breath test, serology). Each of these methods has advantages but also some disadvantages, and none shows an absolute sensitivity and specificity. The second part of the presentation analyses the results obtained with a serologic method using a specific fractioned and purified antigenic complex extracted from Helicobacter pylori. This report demonstrates a good correlation with the other detection methods. Serology appears also as a useful tool for the therapeutical monitoring of infected patients. Serological results must however be interpreted in the light of the complete clinical examination of the patient.
...
PMID:[The role of serology in the diagnosis of Helicobacter (Campylobacter) pylori infection]. 180 38

Helicobacter pylori is a microaerophilic, Gram-negative, spiral rod, the role of which in different gastric diseases has been investigated worldwide since the beginning of the 1980s. H. pylori has been shown to be the causative agent in active chronic gastritis, and it is regularly found in patients endoscopied for duodenal ulcer. The bacterium is also frequently isolated from persons with gastric ulcer, gastric carcinoma and non-ulcer dyspepsia. Apart from cultivation of the bacterium, other diagnostic procedures include various staining methods and urease tests of gastric biopsy samples. The application of non-invasive diagnostic methods, serology and urea breath tests, is rapidly increasing. H. pylori is susceptible to several antimicrobials in vitro, but eradication of the bacterium from the gastric mucosa is not always achieved. The best results until now have been obtained with the combined use of bismuth salts and two antibiotics. In active chronic gastritis and duodenal ulcer patients, eradication of the bacteria has resulted in healing of the disease with permanent decrease of circulating antibodies and negative urease tests. H. pylori has been found worldwide and the infection shows an age-dependent increase. Man, apparently, is the reservoir of the bacterium, but the exact mechanisms of interhuman transmission are still not defined.
...
PMID:Helicobacter pylori and associated gastroduodenal diseases. Review article. 185 43


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

---