Intestinal cancers are developed from intestinal epithelial stem cells(ISCs)in intestinal crypts through a multi-step process involved in genetic mutations of oncogenes and tumor suppressor genes.ISCs play a key role ...Intestinal cancers are developed from intestinal epithelial stem cells(ISCs)in intestinal crypts through a multi-step process involved in genetic mutations of oncogenes and tumor suppressor genes.ISCs play a key role in maintaining the homeostasis of gut epithelium.In 2009,Sato et al established a three-dimensional culture system,which mimicked the niche microenvironment by employing the niche factors,and successfully grew crypt ISCs into organoids or Mini-guts in vitro.Since then,the intestinal organoid technology has been used to delineate cellular signaling in ISC biology.However,the cultured organoids consist of heterogeneous cell populations,and it was technically challenging to introduce genomic changes into three-dimensional organoids.Thus,there was a technical necessity to develop a twodimensional ISC culture system for effective genomic manipulations.In this study,we established a conditionally immortalized mouse intestinal crypt(ciMIC)cell line by using a piggyBac transposon-based SV40 T antigen expression system.We showed that the ciMICs maintained long-term proliferative activity under two-dimensional niche factor-containing culture condition,retained the biological characteristics of intestinal epithelial stem cells,and could form intestinal organoids in three-dimensional culture.While in vivo cell implantation tests indicated that the ciMICs were non-tumorigenic,the ciMICs overexpressing oncogenic b-catenin and/or KRAS exhibited high proliferative activity and developed intestinal adenoma-like pathological features in vivo.Collectively,these findings strongly suggested that the engineered ciMICs should be used as a valuable tool cell line to dissect the genetic and/or epigenetic underpinnings of intestinal tumorigenesis.展开更多
In order to explore the application effect of Oldenlandia polysaccharides(OPS)in the production of AA broilers,2007-day-old AA broilers were randomly divided into 4 groups,namely groups Ⅰ,Ⅱ,Ⅲ,and Ⅳ,each including ...In order to explore the application effect of Oldenlandia polysaccharides(OPS)in the production of AA broilers,2007-day-old AA broilers were randomly divided into 4 groups,namely groups Ⅰ,Ⅱ,Ⅲ,and Ⅳ,each including 50 chicks.The control group(group Ⅰ)was fed with basal diet;and the 3 experimental groups were fed based on the basal diet with the addition of OPS at 0.4 g/kg(group Ⅱ),0.8 g/kg(group Ⅲ),and 1.2 g/kg(group Ⅳ)feed for 1 week,respectively,and then fed the basal diet for 4 weeks.At the ages of 14,28,and 42 d,10 chickens were put into death in the control group and the experimental groups,respectively,and the duodenum and jejunum tissue samples were collected for the analysis of the effects of OPS on the structures of chick intestines.The results showed that at the age of 14 d,the villus lengths of duodenum and jejunum in groups Ⅱ,Ⅲ,and Ⅳ were significantly greater than those in group Ⅰ(P<0.05),and the ratios of duodenal or jejunal villus length to crypt depth in groups Ⅱ and Ⅲ were significantly greater than that in group Ⅰ(P<0.05);at the age of 28 d,the villus length of duodenum in group Ⅱ was significantly greater than that in group Ⅰ(P<0.05);and at the age of 42 d,the ratios of jejunual villus length to crypt depth in groups Ⅱ,Ⅲ and Ⅳ were significantly larger than those of group I(P<0.05).It showed that OPS could promote the small intestine development of AA broilers aged 14 to 42 d.展开更多
文摘Intestinal cancers are developed from intestinal epithelial stem cells(ISCs)in intestinal crypts through a multi-step process involved in genetic mutations of oncogenes and tumor suppressor genes.ISCs play a key role in maintaining the homeostasis of gut epithelium.In 2009,Sato et al established a three-dimensional culture system,which mimicked the niche microenvironment by employing the niche factors,and successfully grew crypt ISCs into organoids or Mini-guts in vitro.Since then,the intestinal organoid technology has been used to delineate cellular signaling in ISC biology.However,the cultured organoids consist of heterogeneous cell populations,and it was technically challenging to introduce genomic changes into three-dimensional organoids.Thus,there was a technical necessity to develop a twodimensional ISC culture system for effective genomic manipulations.In this study,we established a conditionally immortalized mouse intestinal crypt(ciMIC)cell line by using a piggyBac transposon-based SV40 T antigen expression system.We showed that the ciMICs maintained long-term proliferative activity under two-dimensional niche factor-containing culture condition,retained the biological characteristics of intestinal epithelial stem cells,and could form intestinal organoids in three-dimensional culture.While in vivo cell implantation tests indicated that the ciMICs were non-tumorigenic,the ciMICs overexpressing oncogenic b-catenin and/or KRAS exhibited high proliferative activity and developed intestinal adenoma-like pathological features in vivo.Collectively,these findings strongly suggested that the engineered ciMICs should be used as a valuable tool cell line to dissect the genetic and/or epigenetic underpinnings of intestinal tumorigenesis.
文摘In order to explore the application effect of Oldenlandia polysaccharides(OPS)in the production of AA broilers,2007-day-old AA broilers were randomly divided into 4 groups,namely groups Ⅰ,Ⅱ,Ⅲ,and Ⅳ,each including 50 chicks.The control group(group Ⅰ)was fed with basal diet;and the 3 experimental groups were fed based on the basal diet with the addition of OPS at 0.4 g/kg(group Ⅱ),0.8 g/kg(group Ⅲ),and 1.2 g/kg(group Ⅳ)feed for 1 week,respectively,and then fed the basal diet for 4 weeks.At the ages of 14,28,and 42 d,10 chickens were put into death in the control group and the experimental groups,respectively,and the duodenum and jejunum tissue samples were collected for the analysis of the effects of OPS on the structures of chick intestines.The results showed that at the age of 14 d,the villus lengths of duodenum and jejunum in groups Ⅱ,Ⅲ,and Ⅳ were significantly greater than those in group Ⅰ(P<0.05),and the ratios of duodenal or jejunal villus length to crypt depth in groups Ⅱ and Ⅲ were significantly greater than that in group Ⅰ(P<0.05);at the age of 28 d,the villus length of duodenum in group Ⅱ was significantly greater than that in group Ⅰ(P<0.05);and at the age of 42 d,the ratios of jejunual villus length to crypt depth in groups Ⅱ,Ⅲ and Ⅳ were significantly larger than those of group I(P<0.05).It showed that OPS could promote the small intestine development of AA broilers aged 14 to 42 d.
