ABSTRACT
The genotypes of extended spectrum β-laetamases(ESBLs) and AmpC β-lactamases produced by Enterococcus gallinarum isolated from chloebia gouldiae were determined to elucidate the evolution mechanism of the resistant genes.The minimum inhibitory concentrations (MICs) of 18 antibacterial drugs against the Enterococcus gallinarum were detected with two dilution method,and the ESBLs and AmpC β-lactamases from the bacterium were amplified by PCR using the primers of TEM,SHV,CTX-M,ACC,CIT,DHA,EBC,FOX and MOX,respectively.The PCR products were cloned and then the cloned fragments were sequenced to identify their genotypes and subtypes.The bacterium was proved to be a ESBL-producing and AmpC β-lactamase-producing bacterium,showing severe resistant to the other drugs,except the third and forth cephalosporins,carbopenems and fosfomycin.Compared with that of AJ847364 (TEM-116),the sequence of the TEM-type was characterized by two nucleotide mutations (512T→A and 695A→C),which led to two mutations of amino acids(17111e→Lys and 232Lys→Thr),showing that the detected TEM-type was a new genotype,the sequence of the AmpC β-lactamase was similar to that of EF078894 (ACT-like type)with a 97% homology.The genotype of ESBLs of Enterococcus gallinarum was a new TEM-type derived from the TEM-type ESBLs of klebstella pneumoniae isolated from the same avian.The genotype of AmpC lactamase was ACT-type,which probably concerned with β-1actam antibiotics used.
ABSTRACT
Objective To investigate the localization and distribution of the five endocrine cells in the digestive tract mucosa of ricefield eel(Monopterus albus). Methods Using immunocytochemical technique of strept avidin-biotin-peroxidase complex(SABC) were used. Results At least 5 kinds of immunoreactive endocrine cells distributed in the digestive tract mucosa of M.albus. They were gastrin(Gas),somatostatin(Som),5-hydroxytryptamine(5-HT),insulin(Ins),and neurofilament (NF) immunoreactive endocrine(IRE) cells.Gas and Som-IRE cells distributed between stratified squamous epithelium and goblet cell in esophagus. A large number of Gas-IRE cells were found between gastric fundus epithelium and gastric glands, and only a few in the carcia. Ins, 5-HT and NF-IRE cells distributed in the epithelium pylorus and pyloric glandular tube respectively. No any immunoreactive positive reaction was found in the gut of M.albus.In addition, immunoreactive positive reaction of glucagons was not found in whole digestive tract.All immunoreactive endocrine cells were dark brown in color.Their morphology was irregular, cytoplasmic process was shorter and thicker, their nucleus showed an empty bubble.They distributed between esophageal epithelium and gastric epithelium or glandular epithelium, and cytoplasmic process extended to the gastric lumen and glandular cavity.Conclusion There is a complex endocrine function of the digestive system in ricefield eel (M.albus) at the lowest vertebrate.