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

The aims of the present study were to investigate the ecological disturbances caused by four different anti-H. pylori regimens, to compare different methods for diagnosing H. pylori, and to study the genetic variability of H. pylori. The patients included in the study were all treated at the Center of Gastroenterology, Huddinge University Hospital, Karolinska Institute. All patients were H. pylori-positive before entering the study, confirmed by rapid urease test, histology, culture and urea breath test or PCR. Treatment regimens included in the study were omeprazole alone (OP), in combination with amoxicillin (OA), in combination with amoxicillin and metronidazole (OAM) and in combination with clarithromycin and metronidazole (OCM). Samples from the mouth (saliva and dental plaque), stomach (biopsies from the gastric mucosa in the corpus and in the antrum) and the intestine (feces) were collected before, during and after treatment. The oral microflora was challenged by the three treatment regimens including antimicrobial agents, with the emergence of resistant streptococci and staphylococci in the OCM group. Bacterial strains in the gastric mucosa increased in numbers during treatment in all treatment groups, probably due to the pH rise, which provides a better environment for the commensal microflora. This overgrowth was especially pronounced during treatment with omeprazole alone (OP), possibly due to the fact that a concomitant suppression exerted by the antimicrobial agents occurred in the other treatment groups. H. pylori was, on the other hand, suppressed during treatment in all treatment groups, possibly due to a direct effect of omeprazole and to the colonization resistance expressed by the normal microflora. An emergence of resistant commensal strains in the gastric mucosa was seen in the OCM and the OAM groups. The intestinal microflora was most altered in the OAM and the OCM groups, with persistent disturbances in the OCM group 4 weeks after treatment. The frequency of resistant Enterococcus spp. (OCM), Enterobacteriaceae spp. (OA and OAM) and Bacteroides spp. (OCM) was increased during and after treatment. Different detection methods for H. pylori were compared and PCR was shown to have higher sensitivity than other routine diagnostic tests. The patients in the present study seemed to be colonized with a single strain of H. pylori. Treatment failures in patients treated with OAM were caused by recrudescence. These four patients with relapsing H. pylori infection, were shown to be reinfected with the original H. pylori strain, indicating that H. pylori escapes treatment by a thus far unknown mechanism.
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PMID:Microbial ecology and treatment of Helicobacter pylori infections: review. 1076 10

Series of liquid photopolimerized compositions based on oligourethanemetacrylate (OUM-1000T and OUM-2000T) and oligocarbonatemethacrylate (OCM-2), butilmethacrylate, methacrylic that acid, monomethacrylic ether of ethylene glycol and vinylpirrolidone (VP) were tested. It was shown the optimal variant of enzyme sensor development was a composition containing VP (a basic hydrophylic matrix), OCM-2 (crosslinked components) and OUM-2000T (crosslinked and increasing adsorption of polymer component). The blend contains 3% of enzyme. The obtained biosensors as based on immobilized beta-glucose oxidase and ureases have the following charachteristics: the linear response in the range of the concentration 0.1-10 mM, 0.05-20 mM, angle of slope of curve 30 mV/pC, 38 mV/pC, and response time 10-15, 5-10 mines, respectively. The maximal response of urease sensor was in the diapazon of pH 6.0-6.5. The increase of NaCl concentration in the solution to 300 mM caused reduction of sensor response. Under this concentration the was latter equal to half of initial response. Further increase of NaCl concentration (to 500 mM) doesn't lead to further response reduction. K(m) was calculated and it was shown, that amount of immobilized urease and beta-glucose oxidase in photopolymer material was equal 0.85 and 3.1 mM respectively.
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PMID:[Liquid photo-polymerized compositions as an immobilized matrix of biosensors]. 1496 68

The study involved a dynamic comparative efficacy survey of the standard triple and quadruple therapies recommended by the Maastricht Consensus as first line therapies for eradication of Helicobacter pylori infection with the time period of 5 years. The study included 199 Hp-positive patients with stomach ulcer; 101 of them were under examination in 1997 and 98 in 2002. Depending on the therapy type, patients were assigned to one of two groups: the OCM/A group (48 and 53 patients in 1997 and 2002, respectively) was treated with Omeprazole, Clarithromycin and Metronidazole for 7 days and ODTM group (46 and 52 patients in 1997 and 2002, correspondingly) was treated with Omeprazole, De-Nol, Tetracycline and Metronidazole. To discover and confirm Hp eradication, cytological, histological and rapid urease tests were used. Hp eradication was considered as successful when all the tests were negative. The eradication frequency was assessed with the help of ITT and PP analyses. In the OCM/A group Hp was eradicated in 81.3% and 62.3% (p<0.05) of patients when analyzed by the intention-to-treat and in 88.6% and 66.0% (p<0.01) of patients when analyzed by per-protocol in 1997 and 2002, respectively. In the ODTM group Helicobacter pylori was eradicated in 89.1% and 88.5% (p<0.05) of patients when analyzed by intention-to-treat and 95.3% and 93.9% (p<0.05) when analyzed by per-protocol in 1997 and 2002, respectively. The frequency of ulcer cicatrisation and cuticularization of erosions did not depend on the type of the treatment. There was no significant difference between the compliance and side effects of the triple and quadruple therapies. Taking into account the decrease in the efficacy of the triple anti-Hp therapy, the need to use the quadruple therapy as a first line therapy for Hp infection eradication was substantiated.
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PMID:[Methods to optimize the management of Helicobacter pylori infection. The comparative efficacy of the triple and quadruple therapy used as a first line therapy]. 1577 Aug 58

Series of liquid photopolymerizable compositions (LPhPC) based on oligouretanemetacrylate (OUM-1000T and OUM-2000T) and oligocarbonatemetacrylate (OCM-2), monomethacrylic ether of ethylene glycol and vinylpyrrolidone (VP) were tested. It was shown that the LPhPC, which contained VP (as basic hydrophylic matrix), OCM-2 (cross-linking agent) and OUM-2000T (to increase adsorption of polymer) was the most optimal. The blend contained 3 g/100 ml of enzyme. ISFET based biosensors for analysis of glucose and urea had the following characteristics: linear response in the range of concentrations 0.1-10 mmol/l, 0.05-20 mmol/l, angle of slope of concentration curve--30 mV/pC, 38 mV/pC, and response time of approximately 10-15, 5-10 min, correspondingly. The value of Km for immobilized urease and beta-glucose oxidase (GOD) achieved 0.85 and 3.1 mmol/l, respectively. It was established that under immobilization conditions at 20 degrees C the residual activity of GOD was about 35% from the initial level, the residual activity of horseradish peroxidase (HRP) and urease was 42% and 20%, respectively. In case of an immobilization of GOD at -50 degrees C its residual activity reached almost 50% from the initial level. It was investigated how different sources of UV radiation and different substances (including specific and non-specific substrates) influenced stability of the enzymes in the LPhPC and in the prepared membrane at storage. Dynamics of changes of enzyme activity at the process of photo immobilization was characterized, and requirements for enzyme maximal storage were selected. The proposed LPhPC may be prepared in advance since enzymes do not lose their activity during 2 months. Therefore, two processes, i.e. manufacturing of a transducer and preparation of a biological membrane on its surface, can be combined in one. In order to achieve this, approaches of modern electronics, such as for example photolithography, can be used. The developed LPhPC is homogenous, non-active to biological substances, permeable for the analyzed sample, can be prepared using a simple immobilization procedure, and has a defined hydrophobic-hydrophilic balance and sufficient level of adhesion to transducer surfaces. These all cover the requirements to modern biosensors.
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PMID:Liquid photopolymerizable compositions as immobilized matrix of biosensors. 1738 43