Routine Prophylactic Antimicrobial Use Is Associated with Increased Phenotypic and Genotypic Resistance in Commensal Escherichia coli Isolates Recovered from Healthy Fattening Pigs on Farms in Thailand.

This study examined antimicrobial resistance (AMR) profiles in commensal Escherichia coli derived from healthy fattening pigs in Thai farms that used prophylactic antimicrobials (in-feed tiamulin fumarate and amoxicillin) [PAs], therapeutic antimicrobials (injectable enrofloxacin or gentamicin) [TAs], or no antimicrobials [NAs]. Commensal E. coli were used as a proxy for overall AMR on the farms. There was a high level of multidrug resistance in all three categories of farm, with isolates showing resistance to ß-lactams (amoxicillin, ampicillin, and piperacillin) and tetracyclines (tetracycline), and commonly possessing tetA, blaTEM, and plasmid replicons FIB and F. On the other hand, isolates with an extended-spectrum beta-lactamase phenotype (ESBLP) and with resistance to aminoglycosides, chloramphenicol, fluoroquinolones, nitrofurantoin, tiamulin, and trimethoprim/sulfamethoxazole were significantly more common among the PA farms (p < 0.05) than in the other two farm categories. In the PA farms, ESBLP E. coli commonly contained the blaCTX-M-1 group, blaCTX-M-9 group, or both gene groups, and were shown to transfer blaCTX-M genes in a conjugation experiment. E. coli containing N, FIC and A/C replicons were found only in PA farms. In summary, although E. coli isolates from all farms contained a core set of resistance to ß-lactams and tetracyclines, the routine use of PA increased resistance rates to other important antimicrobials.

Anti-inflammatory effects of Aloe vera on leukocyte-endothelium interaction in the gastric microcirculation of Helicobacter pylori-infected rats.

This research was aimed to investigate anti-inflammatory effects of Aloe vera on leukocyte-endothelium in the gastric microcirculation of Helicobacter pylori (H. pylori)-infected rats. Thirty-six male Sprague-Dawley rats were divided into 3 groups: control, H. pylori-infected, and A. vera-treated group (200 mg/kg b.w., twice daily). H. pylori-inoculation was induced in the rats by the administration of H. pylori solution. Intravital fluorescence videomicroscopy was used to examine leukocyte adhesion in postcapillary venules on the posterior surface of stomach area on different periods after administration of A. vera. Serum tumor necrosis factor-alpha (TNF-alpha) level was measured in blood collected at the end of experiment by using ELISA technique. The results showed that in H. pylori-infected group on day 8, the leukocyte adhesion was 13.40+/-1.00 cells/100 microm vessel length and the TNF-alpha was 76.76+/-23.18 pg/ml, which increased significantly (p < 0.05), compared with the control group (leukocyte adhesion(control) = 2.54+/-0.6 cells/100 microm vessel length and TNF-alpha(control) = 9.92+/-2.62 pg/ml). Treatment with A. vera reduced the leukocyte adhesion (5.5+/-0.5 cells/100 microm vessel length), and TNF-alpha (26.31+/-6.38 pg/ml) significantly (p < 0.05). In conclusion, H. pylori enhanced leukocyte-endothelium interaction in the posterior stomach area markedly. This enhancement in leukocyte-endothelium interaction could be improved by the treatment of A. vera, associated with reduction in TNF-alpha level.