Polymerase chain reaction assay for the detection of Helicobacter pylori in gastric biopsy specimens: comparison with culture, rapid urease test, and histopathological tests.

Ulcer recurrence is probably related to residual Helicobacter pylori (H pylori). Histological examination and culture are considered to be the most specific tests. CLO test is a rapid but less specific test, which is usually used as an alternative test to culture. The aim of this study was to investigate the efficiency of a simplified polymerase chain reaction (PCR) assay as a procedure for the diagnosis of gastric H pylori infection of patients. Biopsy specimens were obtained from antral mucosa of 58 patients at endoscopy and submitted to four tests for detection of H pylori. The bacteria were found in 53%, 43%, 48%, and 50% of patients according to the results of PCR, CLO test, culture, and histological examination. Twenty three patients had both negative histology and negative culture and PCR was negative in all of these. Thirteen patients were not classified because only histology or culture was positive and 10 of these had a positive PCR test. When the diagnosis of H pylori was established by agreement with both histology and culture or three positive tests out of four, 29 patients were H pylori positive (28 having had three positive tests and one displaying positive histology and culture), and 26 were negative, and three undetermined. PCR proved the most sensitive and specific test. These results suggest the simplified PCR assay may be a valuable test for the detection of H pylori.

Effect of Pygeum africanum extract on A23187-stimulated production of lipoxygenase metabolites from human polymorphonuclear cells.

Pygeum africanum extract has been used for more than 20 years in France in patients suffering from benign prostatic hypertrophy (BPH). The extract displays anti-inflammatory activity and inhibits bladder hyperreactivity during the above conditions. However, the mechanism of action of P. africanum extract has never been clearly resolved. It has been recently demonstrated that infiltration by inflammatory cells may be involved in the development of BPH. Certain of these cell types, such as macrophages, are known to produce chemotactic mediators including leukotrienes, and thus may contribute to the development of the disease. In order to investigate the potential effect of P. africanum extract on arachidonate metabolism, we examined its effect in vitro on leukotriene (LT) synthesis in human polymorphonuclear cells stimulated with the calcium ionophore A23187. Two formulations of the extract were tested, one dissolved in DMSO and one aqueous solution obtained after alkalinization (0.1 N; NaOH/acidification (0.1 N; HCl). Neither formulation had any effect on cell viability which was above 95% in both cases. P. africanum extract dissolved in DMSO significantly inhibited the production of 5-lipoxygenase metabolites (5-HETE, 20-COOH LTB4, LTB4 and 20-OH LTB4) at concentrations as low as 3 micrograms/ml (p < 0.01), while the same extract dissolved in NaOH/HCl only exhibited an inhibitory effect at 10 micrograms/ml (p < 0.01). This difference apparently reflects the greater solubility of the active components in the extract in DMSO. The ability of P. africanum to antagonize 5-lipoxygenase metabolite production may contribute, at least in part, to its therapeutic activity in inflammatory component of BPH.