Protective effects of ibuprofen against caustic esophageal burn injury in rats.

PURPOSE: The aim of this study was to investigate the efficacy of ibuprofen on the healing of esophagus and the prevention of stricture development after esophageal caustic injuries in rats. MATERIALS AND METHODS: Rats were divided into three groups as: group 1(sham), group 2(esophageal burn injury), group 3(injury + ibuprofen). In groups 2 and 3, a standard esophageal burn injury was created by applying 10% NaOH solution to distal esophagus of about 3 cm. To rats in the sham group, isotonic solution was given instead of NaOH. Ibuprofen (90 mg/kg/day) was given via oral route to group 3 rats. Normal saline as placebo was given via the same route to rats in groups 1 and 2. 28 days later, all the live rats were killed. The distal esophageal segments of all rats were removed and divided into two equal parts for biochemical and histopathologic examination. In the tissue samples, biochemically hydroxyproline and histopathologically collagen content and stenosis indices were evaluated for efficacy of treatment. RESULTS: The hydroxyproline level (microg/mg wet tissue) in the groups was 1.54 +/- 0.08, 4.82 +/- 0.60, and 3.28 +/- 0.27, respectively. The hydroxyproline level increased significantly in group 2 compared with group 1 (P < 0.01). Although the hydroxyproline level was significantly increased in group 3 compared with group 1, it decreased significantly in group 3 compared with group 2 (P < 0.05) by treatment of ibuprofen. In group 3, the collagen content score (1.50 +/- 0.26) was significantly lower than in group 2 (2.62 +/- 0.37) (P < 0.05). The stenosis index was found as 0.37 +/- 0.02 in group 1, 0.84 +/- 0.02 in group 2, and 0.67 +/- 0.03 in group 3. The stenosis index in group 2 was significantly higher than group 1 and group 3 (P < 0.01). Although the stenosis index was significantly higher than in group 1, a significant decrease in stenosis index was found in group 3 compared with group 2, by ibuprofen treatment (P < 0.01). CONCLUSION: Based on these results, we concluded that the treatment with ibuprofen in acute phase esophageal burn injury has beneficial effects on healing of esophagus and may decrease the stricture formation. For these reasons, ibuprofen may effectively be used in the acute phase treatment of caustic esophagus injury and after esophageal dilatation procedures

Extended Aeration Activated Sludge Reactor (EAASR) for Removal of Nitrobenzene: Air Stripped or Biologically Removed?

In this study, the performance of an extended aeration activated sludge reactor (EAASR) was investigated for the removal of nitrobenzene (NB), a commonly used organic chemical in various industries. In a set of experiments, increasing NB concentrations between 1 and 800 mg/L were applied to the EAASR. Synthetic wastewater containing NB was successfully treated up to 92.0 and 100.0% in terms of chemical oxygen demand (COD) and NB removal. The major NB removal mechanism in this EAASR was assessed to be air stripping after kinetic evaluation as compared to somewhat limited bacterial degradation of NB. Although NB is known to be toxic, the removal efficiency of NB was never below 97.4% even at high NB concentrations. Under lower NB concentrations, it was found that the bacterial floc formation was intact with existing Ciliata and Rotifera. However, at higher NB concentrations, free swimming Ciliata and Rotifera specimens disappeared while the flocs became smaller and dispersed. © 2016 by De Gruyter 2016