Mohan V P, Sharma K B, Agarwal D S, Purnima G, Pillai P K
Department of Microbiology, Maulana Azad Medical College, New Delhi, India.
J Diarrhoeal Dis Res. 1995 Sep;13(3):166-71.
One hundred twenty-six isolates of Salmonella typhimurium from various clinical sources were tested for enterotoxin production and characterization of plasmid profile. Cell-free culture supernates and polymyxin B extracts of all the strains were assayed by rabbit ileal loop and skin permeability tests. Enterotoxic activity was detected in culture supernates of 32 strains. Twenty-one strains by both rabbit ileal loop and skin permeability tests, nine strains by skin permeability test, and two strains by rabbit ileal loop test were positive. Live culture of three enterotoxic strains, positive in culture supernates produced ileal secretion. Polymyxin B extracts from 6 hours and 18 hours broth cultures of all the strains were devoid of enterotoxicity. Ileal mucosa exposed to culture supernate of enterotoxigenic strains showed swollen and blunted villi with submucosal oedema while those exposed to polymyxin B extracts showed shortening of villi and sloughing of epithelial lining. Plasmid profiles of enterotoxigenic strains were heterogenous and grouped into 20 different profiles. No correlation could be established between plasmid profile, R-pattern, and enterotoxin production.
对来自各种临床来源的126株鼠伤寒沙门氏菌进行了肠毒素产生情况及质粒图谱特征分析。所有菌株的无细胞培养上清液和多粘菌素B提取物通过兔回肠袢试验和皮肤通透性试验进行检测。在32株菌株的培养上清液中检测到了肠毒素活性。通过兔回肠袢试验和皮肤通透性试验均呈阳性的有21株，通过皮肤通透性试验呈阳性的有9株，通过兔回肠袢试验呈阳性的有2株。3株培养上清液呈阳性的产肠毒素菌株的活菌培养物可引起回肠分泌。所有菌株在6小时和18小时肉汤培养后的多粘菌素B提取物均无肠毒素活性。暴露于产肠毒素菌株培养上清液的回肠黏膜显示绒毛肿胀、变钝，伴有黏膜下水肿，而暴露于多粘菌素B提取物的回肠黏膜则显示绒毛缩短和上皮衬里脱落。产肠毒素菌株的质粒图谱各异，分为20种不同的图谱。在质粒图谱、R型和肠毒素产生之间无法建立相关性。
