http://chineseinput.net/에서 pinyin(병음)방식으로 중국어를 변환할 수 있습니다.
변환된 중국어를 복사하여 사용하시면 됩니다.
CagA Phosphorylation‐Dependent MMP‐9 Expression in Gastric Epithelial Cells
Nam, Young‐,Hee,Ryu, Eunju,Lee, Doyeon,Shim, Hyun Jae,Lee, Yong Chan,Lee, Seung‐,Taek Blackwell Publishing Ltd 2011 Helicobacter Vol.16 No.4
<P><B>Abstract</B></P><P><B>Background: </B> Infection of <I>cagA</I>‐positive <I>Helicobacter pylori</I> is associated with increased expression of MMPs in gastric epithelial cells. The role of phosphorylated CagA in the induction of MMP‐9, a protease‐degrading basement membrane, in gastric epithelial cells has not been clearly defined yet. The aim of this study is to analyze whether the presence of CagA and its phosphorylation status play a role in increased expression of MMP‐9 in gastric epithelial cells.</P><P><B>Materials and Methods: </B> Induction of MMP‐9 secretion was analyzed in gastric epithelial AGS cells harboring CagA with or without EPIYA motif, which is injected by <I>H.?pylori</I> or ectopically expressed. In addition, signaling pathways involved in the CagA‐dependent MMP‐9 production have been studied.</P><P><B>Results: </B> The 147C strain of <I>H.?pylori</I> expressing tyrosine‐phosphorylated CagA (EPIYA present) induced higher MMP‐9 secretion by AGS cells than the 147A strain expressing non‐tyrosine‐phosphorylated CagA (EPIYA absent). In addition, in bacteria‐free CagA‐inducible AGS cells, expression of wild‐type CagA induced more MMP‐9 secretion than phosphorylation‐resistant CagA. Inhibition of CagA phosphorylation by the Src family kinase inhibitor PP1 downregulated CagA‐mediated MMP‐9 secretion. Knockdown of SHP‐2 phosphatase dramatically reduced MMP‐9 secretion. ERK inhibitors, PD98059 and U0126, and NF‐κB pathway inhibitors, sulfasalazine and <I>N</I>‐acetyl‐<SMALL>l</SMALL>‐cysteine, also inhibited MMP‐9 expression.</P><P><B>Conclusion: </B> These results support a model whereby the EPIYA motif of CagA is phosphorylated by Src family kinases in gastric epithelial cells, which initiates activation of SHP‐2. In addition, they suggest that the resultant activation of ERK pathway along with CagA‐dependent NF‐κB activation is critical for the induction of MMP‐9 secretion.</P>
Namyoung Paik,Eun Ran Kim,Tae Jun Kim,Sung Noh Hong,Dong Kyung Chang,Young-Ho Kim 거트앤리버 소화기연관학회협의회 2019 Gut and Liver Vol.13 No.2
Background/Aims: The quality of bowel preparation is important for optimal colonoscopy. It is influenced by medical and personal factors. We aimed to evaluate the effect of bowel habit on the quality of bowel preparation and to identify predictors of inadequate bowel preparation among bowel habit factors. Methods: From June 2017 to September 2017, 90 volunteers were enrolled in this study. Each participant answered a questionnaire consisting of multiple questions about personal bowel habits, including stool form, frequency of bowel movements per week, duration, and degree of straining for bowel movement. Then, all volunteers underwent colonoscopic exam. Eleven endoscopists performed colonoscopies and used the Boston Bowel Preparation Scale (BBPS) as the index for bowel preparation. Two expert endoscopists simultaneously reviewed all colonoscopic images to confirm the final BBPS. Univariate and multivariate logistic regression analyses were performed to verify the correlation between bowel preparation adequacy and bowel habit. Results: Among the 90 participants, 20 (22.2%) had inadequate bowel preparation (total BBPS ≤6 or any segmental BBPS ≤1). In univariate analysis, infrequent bowel movement (0–2/week) (odds ratio [OR], 12.60; 95% confidence interval [CI], 1.22 to 129, p=0.03) and moderate straining (more than 1/4 of defecations) (OR, 4.40; 95% CI, 1.44 to 13.39; p=0.01) were significantly associated with inadequate bowel preparation. However, only moderate straining was significantly associated with inadequate bowel preparation in multivariate analysis (OR, 3.99; 95% CI, 1.26 to 12.65; p=0.02). Conclusions: Straining is a significant predictor for inadequate bowel preparation. For patients with straining during bowel movements, an intensified preparation regimen should be considered.
Nakyoung Kim(김나경),Dae-hyuk Kweon(권대혁),Sung-Koo Kim(김성구) 한국생명과학회 2012 생명과학회지 Vol.22 No.6
본 연구는 어류 병원균의 비 유전성을 가지는 항생제 내성균인 persister cell에 관한 연구이다. Persister cell은 기존의 항생제를 분해하는 저항균체(resistant cell)와는 다른 특성으로 항생제에 대한 저항성을 가지는데, 항생제가 존재하는 환경에서 새로운 기작으로 항생제에 대한 내성을 형성한다. 그래서 기존의 양식장에서 어류를 키울때 어류에 투여하는 항생제는 일반적인 균주의 사멸 항생제 농도보다 더 높은 농도의 항생제를 투여하게 된다. 특히, E. tarda에 대한 다양한 항생제가 개발되어 있지만 내성균의 출현으로 그 효과가 좋지 않으며, 또한 persister cell에 의한 질병 재발을 방지하기 위해 균사멸 농도보다 훨씬 높은 농도의 항생제를 처리하고 있다. Persiser cell의 특이적인 저감 효과를 확인 하기 위하여 선별된 3종의 식물 추출물(돌외, 예덕나무, 상산)을 항생제와 함께 사용하였으며, 돌외와 예덕나무가 100 ㎍/㎖, 상산은 200 ㎍/㎖의 농도에서 persister cell의 사멸효과를 나타내었다. 또한 넙치를 이용한 12일간의 누적 폐사율을 조사한 결과, 식물 추출물과 항생제 혼합액의 복강 투여구가 항생제 단독의 복강 투여구 보다 낮은 누적 폐사율이 관찰되었고, 항생제에 첨가한 식물 추출물의 농도가 돌외 30 ㎍/㎖, 예덕나무 10 ㎍/㎖, 상산 10 ㎍/㎖의 농도 투여구에서 가장 낮은 누적 폐사율을 나타내었다. 따라서 본 연구에 사용된 세가지 추출물들(돌외, 예덕나무, 상산)은 항균 활성을 가지지 않은 농도에서 항생제와 병용하여 persister cell의 저감 효과가 있음을 확인하였다. High concentration of antibiotics has been used to treat the outbreak of edwardsiellosis caused by Edwardsiella tarda in aquaculture. However, not all of the bacteria have been killed with high concentrations of antibiotics treatment by the formation of persister cells with a dormant state. The main objective of this study was to kill persister cell using antibiotics with the addition of natural plant compounds. Antibiotics used in this study consist of 100 ㎎/㎖ florfenicol and 100 ㎎/㎖ amoxicillin. Ten natural plant compounds with persister cell inhibitor activity to E. coli were obtained from Protein Engineering and Systems Biology Lab. of Sungkyunkwan University. The persister cell inhibition activities of those natural plant compounds were evaluated in test tube. Concentrations of the antibiotics were in the ranges of 25~200 ㎍/㎖. The persister cell formation was observed after 16 hours of culture. Persister cells were killed by antibiotics with natural plant compounds. Among ten natural plant compounds, Gynostemma pentaphyllum, Mallotus japonicus, and Orixa japonica showed persister cell formation inhibition activities. The optimal concentrations of G. pentaphyllum, M. japonicus, and O. japonica for the inhibitor of persister cell formation were 100 ㎍/㎖, 100 ㎍/㎖, and 200 ㎍/㎖, respectively. In vivo study was carried out to evaluate the effect of the antibiotics with natural plant compounds using aquacultural fish, olive flounder, as test animals. G. pentaphyllum, M. japonicus, and O. japonica of 30 ㎍/㎖, 10 ㎍/㎖, and 10 ㎍/㎖ with antibiotics reduced cumulative mortalities, showing the effectiveness of persister cell inhibition.