ABSTRACT
Objective@#To analyze the antimicrobial resistance and multilocus sequence typing (MLST) results of extended-spectrum β-lactamase (ESBLs)-producing Escherichia coli in rural residents in villages with pig breeding farms in a county of Shandong province.@*Methods@#Antimicrobial susceptibility testing was performed with agar dilution method by using 360 ESBLs-producing E. coli strains from fresh stool samples of rural residents in villages with pig breeding farms in a county of Shandong. PCR was conducted to amplify the CTX-M, TEM, SHV genes and capillary electrophoresis was used to screen positive strains in July, 2016. MLST was performed for molecular typing analysis, and eBURST v3.0 software was used for cluster analysis.@*Results@#Among 360 strains of ESBLs-producing E. coli, the resistance rates to cefotaxime, tetracycline, trimethoprim-sulfamethoxazole and florfenicol were 100.0% (360/360), 82.2% (296/360), 81.1% (292/360) and 80.3% (289/360), respectively. The positive rate of CTX-M gene was 99.2% (357/360), in which the positive rate of CTX-M-9 was 35.6% (128/360) and the positive rate of CTX-M-1 was 24.4% (88/360). The positive rate of TEM gene was 26.9% (97/360). A total of 132 STs were identified through MLST. The predominant ST was ST10, accounting for 12.5% (45/360). Cluster analysis showed that CC10 was the most important clone group, including 39 ST clones, involving 148 strains (41.1%).@*Conclusions@#The drug resistances of ESBLs-producing E. coli to cefotaxime, tetracycline, trimethoprim-sulfamethoxazole and flurfenicol are serious in this rural area. There is a small-scale clustering of CC10 and transmission mode from animals to humans might exist.
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Objective To study the gene expressions of nestin and stem cell factor(SCF)in neurons after ischemia-reperfusion injury in rat brain. Methods Thirty-six adult female rats were subject to left middle cerebral artery occlusion for 1.5h and different hours of reperfusion. In site hybridization was used to examine the expression of nestin and SCF mRNA in the rats subjected to 2h, 6h, 12h, 24h, 2d, 3d, 7d, 14d of reperfusion and sham-operation group (n=4). Results (1) Nestin expression in cortex, striatum and extraventricular zone was weak in the sham-operation group, and increased markedly in the ischemic hemisphere compared with sham-operation group except of reperfusion 2h in cortex, 2h, 6h in striatum, 2h, 6h and 14d in extraventricular zone. (2)SCF expression in cortex, striatum and extraventricular zone was weak in the sham-operation group, and increased markedly in the ischemic hemisphere compared with sham-operation group except of reperfusion 2h, 6h, 12h in cortex, 2h, 6h in striatum, 2h and 14d in extraventricular zone. Conclusion It is suggested that SCF expression might enhance the proliferation of neural stem cells following ischemia-reperfusion in rats.
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Objective To observe the effects of expressions of neurocyte adhesion molecule (NCAM) and growth associated protein-43 (GAP-43) in neurological function recovery following cerebral ischemia-reperfusion in rats. Methods The model of focal ischemia-reperfusion in SD rat was induced by intraluminal middle cerebral artery (MCA) occlusion with a nylon monofilament suture. In situ hybridization (ISH) was performed to examine the expression of NCAM mRNA and GAP-43 mRNA at 2,12 h and 1,2,3,7,14 d after reperfusion and in sham-operated controls. Results There was no functional deficit and little expression of NCAM mRNA and GAP-43 mRNA in brain cells in rats of the sham-operated group. In the experimental group, NCAM mRNA expression was observed after reperfusion for 2 h in cortex and striatum and peaked at 12 h and was still higher at 7 d. The neurological function improved at reperfusion of 3 d~14 d compared to reperfusion 2 h. In the ischemic cortex and striatum, GAP-43 mRNA expression demonstrated "double-peak" at 12 h and 2 d after reperfusion, then decreased gradually to the level of sham-operated group at 14 d. Conclusion The increasing NCAM expression might be an important factor of the neural reparation and GAP-43 might enhance the neurological functional recovery with ischemic brain injury in rat.