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Yong Luo Yang Zou Li-ping Li Zhao-zhen Wang Li-qun Wang Zi-yu Zhang 《Gynecological endocrinology》2020,36(10):895-901
AbstractOxidative stress (OS) has been proposed to play a role in the development of EMs. Peroxiredoxins are a family of antioxidant proteins that exhibit peroxidase activity in a thioredoxin-dependent manner, protecting cells against OS. The Western blotting results showed that the relative expression of PRDX4 was significantly increased in ectopic endometria compared with the normal endometria of EMs-free (p?<?.05). The H2O2 concentration was also significantly higher in the ectopic endometrium. PRDX4 siRNA was transfected into primary ectopic endometrial stromal cells (EESCs). The viability of the transfected EESCs was measured by CCK-8 assay, and the results showed significantly decreased cell viability. Furthermore, the apoptosis rate and ROS generation in flow cytometry assays were significantly increased after the knockdown of PRDX4 expression (p?<?.05). Scratch assays and transwell assays revealed that decreased expression of PRDX4 mediated by siRNA inhibited EESC migration and invasion. In conclusion, these findings indicate the potential role of PRDX4 in the development of EMs and PRDX4 as a possible therapeutic target for EMs treatment. 相似文献
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目的探讨血小板第4因子(platelet factor 4,PF4)对5.0 Gy γ射线全身照射小鼠的骨髓基质细胞(bone marrow stromal cells,BMSCs)的保护作用,进一步探讨PF4对造血的辐射防护机制.方法30只雄性小鼠随机分为3组:①放射组,②PF4保护组,③对照组.小鼠照射前分别于26和20 h腹腔内注射PF4,每次剂量50 μg/kg.于照射后3 d取骨髓细胞体外培养,分别计数培养后3、7和14 d的骨髓基质细胞集落(CFU-F);在培养后10 d流式细胞仪检测细胞周期.结果3组中,照射组3 d的CFU-F数量与PF4保护组差异无统计学意义,7和14 d的CFU-F数量PF4保护组较照射组明显增加.流式细胞仪检测结果表明3组中照射组G0+G1期细胞明显高于其余两组,S,G2+M期细胞明显低于其余两组.结论PF4对照射小鼠的骨髓基质细胞有保护作用,促进造血重建. 相似文献
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Akira Sawaki Nobumasa Mizuno Kuniyuki Takahashi Tsuneya Nakamura Masahiro Tajika Hiroki Kawai Toshifumi Isaka Hiroshi Imaoka Yasuyuki Okamoto Masatoshi Aoki Hiroyuki Inoue Ahmed AS Salem Yasushi Yatabe Kenji Yamao 《Digestive endoscopy》2006,18(1):40-44
Background: Gastrointestinal stromal tumors (GIST) are one of the most common mesenchymal tumors of the gastrointestinal tract. GIST are defined by positive immunohistochemical staining for KIT or CD34 and thus are generally diagnosed after surgery. Because small GIST are rarely diagnosed before surgery, the clinical course of these small tumors is not clear. The aim of the present study was to follow changes in size and configuration of small GIST that were pathologically confirmed using endoscopic ultrasonography‐guided fine‐needle aspiration biopsy (EUS‐FNAB). Methods: Between July 1997 and December 2003, 16 tumors in 16 patients (10 men and 6 women) with an immunohistochemical diagnosis of GIST were regularly followed in our hospital. The median patient age when EUS‐FNAB was performed was 62 years (range 26–82 years) and the median follow‐up period was 4.9 years (range 0.5–9.6 years). Results: Fourteen tumors showed no remarkable changes in size and shape during follow up compared with the initial diagnosis. Two tumors enlarged: one tumor approximately doubled its diameter in 8 years and the other tumor increased from 1.8 cm at diagnosis to up to 10 cm after only 2 years. Doubling time of the latter tumor was calculated as 3.1 months. Conclusions: We conclude that EUS‐FNAB might be a good modality for final diagnosis of GIST without surgery, and that GIST without rapid growth on follow up can be endoscopically followed. 相似文献
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JAE YOUNG JOUNG DONG GOO KANG HYUCK-JAE CHOI WEON SEO PARK HO KYUNG SEO JIN SOO CHUNG KANG HYUN LEE 《International journal of urology》2006,13(11):1451-1453
Abstract Gastrointestinal stromal tumor (GIST) is a recently described mesenchymal tumor that can develop in any portion of the gastrointestinal tract. The occurrence of a GIST in the urinary tract is rare, but GIST can present as tumor of the urinary tract or invade the urinary tract. This is the first reported case of GIST in the ileal neobladder, which presented as a submucosal tumor. The patient underwent an open exploration and partial resection of the neobladder pouch. 相似文献
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Xiaoguang Chen Yi Li Lei Wang Mark Katakowski Lijie Zhang Jieli Chen Yongxian Xu Subhash C. Gautam Michael Chopp 《Neuropathology》2002,22(4):275-279
Intravenous administration of human bone marrow stromal cells (hMSCs) after middle cerebral artery occlusion (MCAo) in rats provides functional benefit. We tested the hypothesis that these functional benefits are derived in part from hMSC production of growth and trophic factors. Quantitative sandwich enzyme‐linked immunosorbent assay (ELISA) of hMSCs cultured with normal and MCAo brain extracts were performed. hMSCs cultured in supernatant derived from ischemic brain extracts increased production of brain‐derived neurotrophic factor (BDNF), nerve growth factor (NGF), vascular endothelial growth factor (VEGF) and hepatocyte growth factor (HGF). These neurotrophins and angiogenic growth factors increased in a post‐ischemia time‐dependent manner. The hMSC capacity to increase expression of growth and trophic factors may be the key to the benefit provided by transplanted hMSCs in the ischemic brain. 相似文献
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目的应用重组人骨形态发生蛋白4基因腺相关病毒载体(AAV-hBMP4)转染兔骨髓基质干细胞(BMSCs),观察其对BMSCs生物学行为的影响,从而为骨组织工程寻找理想的病毒载体及种子细胞。方法全骨髓法培养兔BMSCs,按感染复数(MOI)值不同设定为四组,分别转染兔BMSCs,观察病毒量对细胞形态的影响。选取影响最小的MOI值,进行后续实验。转染兔BMSCs,MTT法描记细胞生长曲线,观察AAV对细胞增殖活性的影响。以重组增强型绿色荧光蛋白基因的腺相关病毒载体(AAV-EGFP)为参照,行流式细胞仪检测,计算转染效率。AAV-hBMP4与对照病毒AAV-EGFP分别转染细胞,观察细胞形态,行碱性磷酸酶(ALP)染色、Von Kossa染色及ALP含量测定,观察成骨活性。兔肌袋实验观察异位成骨情况。结果MOI值为5×10~4 vg/cell时,AAV对细胞形态影响最小,以此值进行后续实验。AAV转染后,细胞增殖活性良好,转染效率为55%~65%。AAV-hBMP4转染后,细胞形态呈现典型的成骨改变,ALP染色及Von Kossa染色均出现成骨的特征性改变,而AAV-EGFP组无上述改变。细胞上清ALP含量测定显示,实验组ALP含量显著增高,与对照组比较差异有统计学意义(t=218.65,P<0.01)。兔肌袋实验术后4周组织学检测可见大量钙盐沉积,矿化结节形成。结论AAV-hBMP4转染效率高,对BMSCs的增殖活性影响小,AAV-hBMP4转染的BMSCs可望成为组织工程化骨的理想种子细胞。 相似文献
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目的 研究兔角膜基质细胞在体外长期培养传代过程中,细胞增殖能力和胞外基质表达水平的改变。方法 取体外培养兔角膜基质细胞,由光镜对各代细胞的形态学变化进行观测。通过对各代细胞生长曲线的绘制,得出其各自的群体倍增时间;MTT法比较各代细胞增殖能力的改变。RT-PCR和Western杂交检测各代细胞中Ⅰ、Ⅲ型胶原表达水平的改变;爱茜蓝法检测糖胺聚糖(GAG)的含量。结果 体外培养兔角膜基质细胞随着传代的进程,逐渐显现衰老的形态特征。细胞群体倍增时间由第7代起显著延长(P<0.01);MTT比色法的结果亦显示,第7代细胞的增殖能力开始大幅下降(P<0.01)。第9-11代时,Ⅰ、Ⅲ型胶原在mRNA和蛋白水平的表达都有明显减少(P<0.01),降至第1代细胞的30%左右;GAG的含量也降至40%左右。结论 兔角膜基质细胞经历长期体外培养后,细胞增殖能力和胞外基质表达水平显著下降,逐渐丧失原有的功能。但作为构建组织工程化角膜的种子细胞,在它的生物学特性未发生改变之前,经3次传代培养,获取的细胞量达到组织块消化所得细胞的240倍左右,已足以用于构建之用。 相似文献