核桃低聚肽对６０Ｃｏγ射线照射小鼠氧化损伤 保护作用的实验研究

摘要：目的　探讨核桃低聚肽（ＷＯＰｓ）对６０Ｃｏγ射线辐照小鼠氧化损伤的保护作用。方法　将９６ 只ＳＰＦ 级雌性ＢＡＬＢ／ｃ小鼠随机分为６ 组：空白对照组、模型对照组、乳清蛋白组（０．４４ｇ／ｋｇ）、ＷＯＰｓ组低、 中、高组（０．２２ｇ／ｋｇ、０．４４ｇ／ｋｇ、０．８８ｇ／ｋｇ），连续饮水途径给予不同溶液第１４ 天，除空白对照组外， 所有小鼠全身照射３．５ Ｇｙ剂量６０Ｃｏγ 射线，分别在辐照后第３ 天和第１４ 天检测小鼠血清及肝脏ＳＯＤ、 ＧＳＨ Ｐｘ活性及ＭＤＡ 含量。结果　辐照降低了小鼠肝脏及血清ＳＯＤ、ＧＳＨ Ｐｘ含量，增高了ＭＤＡ 含量。 辐照后第３ 天，ＷＯＰｓ中组小鼠肝脏及血清ＳＯＤ 活性均高于模型对照组和乳清蛋白组（犘＜０．０５）；辐照后 第１４ 天，ＷＯＰｓ低组小鼠肝脏及血清ＳＯＤ 活性均高于模型对照组和乳清蛋白组（犘＜０．０５）。辐照后第 ３ 天，ＷＯＰｓ低组小鼠肝脏及血清ＧＨＳ Ｐｘ 活性均高于模型对照组和乳清蛋白组（犘＜０．０５）； 辐照后第 １４ 天，ＷＯＰｓ低组小鼠肝脏及血清ＧＳＨ Ｐｘ活性均高于模型对照组和乳清蛋白组（犘＜０．０５）。辐照后第 ３ 天，ＷＯＰｓ低、中组小鼠肝脏和血清ＭＤＡ 含量均低于模型对照组和乳清蛋白组（犘＜０．０５）； 辐照后 第１４ 天，ＷＯＰｓ低、中、高组小鼠肝脏及血清ＭＤＡ 含量均低于模型对照组和乳清蛋白组（犘＜０．０５）。结 论　ＷＯＰｓ对辐照所致氧化损伤具有一定的保护作用。 关键词：核桃低聚肽；辐照；氧化损伤；超氧化物歧化酶；谷胱甘肽过氧化物歧化酶；丙二醛 中图分类号：Ｒ１５１　　文献标识码：Ａ　　文章编号：１００９ ６６３９ （２０１９）０３ ０２１２ ０５

Isolation of cronobacter spp.from stool samples of individuals in different age groups

Objective To understand the epidemiological features of cronobacter spp.in individuals with different age,and to compare the methods used for cronobacter spp.isolation and identification from stool samples. Methods Fecal samples were collected and cronobacter bacteria were isolated by culturing bacteria on plate directly or after bacteria enrichment.Cronobacter bacteria were further identifed by biochemical test and realtime PCR,and fusA gene sequence anlysis was used to determine the species of cronobacter. Results A total of 27strains of cronobacter were isolated from 1 285fecal samples with the overall positive rate of 2.1%. The differencs of isolation rate among samples from different age groups were not statistically significant（P〉 0.05）.There were 4speices identified out of 27strains,majority of them were cronobacter sakazakii and cronbacter malonaticus.CSB and CCI methods were found to be more effective for cronobacter isolation compared to mLST and ELA. Conclusions Although cronobacter bacteria are potentially harmful to all age groups,infants are more volnerable to the bacteria infection,therefore,it is important to reinforce the surveillance in order to control cronobacter infection.