Severity: Warning
Message: file_get_contents(https://...@gmail.com&api_key=61f08fa0b96a73de8c900d749fcb997acc09): Failed to open stream: HTTP request failed! HTTP/1.1 429 Too Many Requests
Filename: helpers/my_audit_helper.php
Line Number: 143
Backtrace:
File: /var/www/html/application/helpers/my_audit_helper.php
Line: 143
Function: file_get_contents
File: /var/www/html/application/helpers/my_audit_helper.php
Line: 209
Function: simplexml_load_file_from_url
File: /var/www/html/application/helpers/my_audit_helper.php
Line: 3098
Function: getPubMedXML
File: /var/www/html/application/controllers/Detail.php
Line: 574
Function: pubMedSearch_Global
File: /var/www/html/application/controllers/Detail.php
Line: 488
Function: pubMedGetRelatedKeyword
File: /var/www/html/index.php
Line: 316
Function: require_once
Severity: Warning
Message: Attempt to read property "Count" on bool
Filename: helpers/my_audit_helper.php
Line Number: 3100
Backtrace:
File: /var/www/html/application/helpers/my_audit_helper.php
Line: 3100
Function: _error_handler
File: /var/www/html/application/controllers/Detail.php
Line: 574
Function: pubMedSearch_Global
File: /var/www/html/application/controllers/Detail.php
Line: 488
Function: pubMedGetRelatedKeyword
File: /var/www/html/index.php
Line: 316
Function: require_once
Aromatic amines, such as benzidine (BZ), initiate bladder cancer in humans. Inflammation/infection play an important role in this cancer. This study was designed to assess the influence of inflammatory oxidants, including reactive nitrogen oxygen species (RNOS), on BZ transformation and activation. RNOS were generated under various conditions and reacted with BZ, and the products were examined by HPLC. Conditions that generate nitrogen dioxide radical, NO(2)(-) + myeloperoxidase + H(2)O(2) and ONOO(-), produced primarily a single new product, which was identified by MS as azobenzidine (AZO-BZ). The myeloperoxidase-catalyzed reaction was inhibited by 1 mM cyanide and did not require NO(2)(-). Chloride (100 mM) reduced the myeloperoxidase reaction by 30% with taurine having little effect. In contrast, conditions that generate N(2)O(3), i.e., NO donor diethylamine (DEA) NONOate, produced two products, which were identified by MS as 4'-OH-4-aminobiphenyl (4'-OH-ABP) and 4-aminobiphenyl (ABP). 2-(4-Carboxyphenyl)-4,4,5,5-tetramethylimidazoline-1-oxyl-3-oxide, an oxidant of NO thought to produce NO(2)(*), had a biphasic effect on product formation. At a concentration equal to DEA NONOate, a 5-fold increase in BZ nitrosation was observed, while at higher concentrations nitrosation was greatly diminished and formation of AZO-BZ occurred. Glutathione prevented RNOS transformation of BZ. With MPO and ONOO(-), a new product was formed that cochromatographed with 3-(glutathione-S-yl)BZ. Glutathione also prevented nitrosation of BZ but did not form additional BZ products. HOCl-mediated activation of BZ, 4'-OH-ABP, and ABP to bind DNA was assessed. A higher level of binding was observed at pH 5.5 than pH 7.4. BZ elicited the most binding. More binding was observed at both pH values with 4'-OH-ABP than ABP. Thus, components of the inflammatory response are capable of BZ transformation and activation.
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Source |
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http://dx.doi.org/10.1021/tx0200966 | DOI Listing |
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