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21.
Yali She Yi Li Yongqi Liu Guli Asai Shaobo Sun Jianxin He Zheng Pan Yan Cui 《Acta biochimica et biophysica Sinica》2013,(12):1011-1020
In this study, we assessed the toxic effects of formaldehyde (FA) on mouse bone marrow mesenchymai stem cells (BM- MSCs). Cytotoxicity was measured by using MTT assay. DNA strand breakage was detected by standard alkaline comet assay and comet assay modified with proteinase K (PK). DNA-protein crosslinks (DPCs) were detected by KCI-SDS precipitation assay. We found that FA at a con- centration from 75 to 200 μM inhibited cell survival and induced DPCs over 125 μM. The PK-modified comet assay showed that FA-induced DNA strand breakage was increased in a dose-dependent manner from 75 to 200 μM. On the other hand, standard alkaline comet assay showed that DNA strand breakage was decreased with FA concen- tration over 125 μM. We confirmed by using Pearson cor- relation that there was a negative linear correlation between DPCs and survival rate (r = -0.987, P 〈 0.01) and positive linear relationships between DPCs and (i) sister chromatid exchange and (ii) micronucleus (r = 0.995, P〈 0.01; r = 0.968, P〈 0.01). DNA damage RTz profiler polymerase chain reaction array was used to investigate the changes in the expression of damage response genes. Xpa and Xpc of the nucleotide excision repair pathway and Brca2, Rad51, and Xrcc2 of the homologous recombination pathway were all up-regulated in both 75 and 125 μM FA. However, the same genes were down-regulated with 175 μM FA. The expressions of Chekl and Husl, which are involved in cell cycle regulation, were altered in the same manner with 75, 125, and 175 μM FA. These results indicated that Xpa, Xpc, Brca2, Rad51, Xrcc2, Chekl, and Husl were essential for the BM-MSCs to counteract the effects of FA. 相似文献
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Akiko Shibui Ayako Takamori Mohammed E.M. Tolba Aya Nambu Eri Shimura Sachiko Yamaguchi Chizu Sanjoba Hajime Suto Katsuko Sudo Ko Okumura Sumio Sugano Hideaki Morita Hirohisa Saito Kenji Matsumoto Susumu Nakae 《Biochemistry and Biophysics Reports》2016
IL-25, IL-33 and TSLP, which are produced predominantly by epithelial cells, can induce production of Th2-type cytokines such as IL-4, IL-5 and/or IL-13 by various types of cells, suggesting their involvement in induction of Th2-type cytokine-associated immune responses. It is known that Th2-type cytokines contribute to host defense against malaria parasite infection in mice. However, the roles of IL-25, IL-33 and TSLP in malaria parasite infection remain unclear. Thus, to elucidate this, we infected wild-type, IL-25?/?, IL-33?/? and TSLP receptor (TSLPR)?/? mice with Plasmodium berghei (P. berghei) ANKA, a murine malaria strain. The expression levels of IL-25, IL-33 and TSLP mRNA were changed in the brain, liver, lung and spleen of wild-type mice after infection, suggesting that these cytokines are involved in host defense against P. berghei ANKA. However, the incidence of parasitemia and survival in the mutant mice were comparable to in the wild-type mice. These findings indicate that IL-25, IL-33 and TSLP are not critical for host defense against P. berghei ANKA. 相似文献
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Cohesin is a ring‐shaped protein complex that plays a crucial role in sister chromatid cohesion and gene expression. The dynamic association of cohesin with chromatin is essential for these functions. However, the exact nature of cohesin dynamics, particularly cohesin translocation, remains unclear. We evaluated the dynamics of individual cohesin molecules on DNA and found that the cohesin core complex possesses an intrinsic ability to traverse DNA in an adenosine triphosphatase (ATPase)‐dependent manner. Translocation ability is suppressed in the presence of Wapl‐Pds5 and Sororin; this suppression is alleviated by the acetylation of cohesin and the action of mitotic kinases. In Xenopus laevis egg extracts, cohesin is translocated on unreplicated DNA in an ATPase‐ and Smc3 acetylation‐dependent manner. Cohesin movement changes from bidirectional to unidirectional when cohesin faces DNA replication; otherwise, it is incorporated into replicating DNA without being translocated or is dissociated from replicating DNA. This study provides insight into the nature of individual cohesin dynamics and the mechanisms by which cohesin achieves cohesion in different chromatin contexts. 相似文献
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Yosuke Kanno Akira Ishisaki Eri Kawashita Hiromi Kuretake Kanako Ikeda Osamu Matsuo 《International journal of biological sciences》2016,12(1):63-71
Chronic inflammatory diseases, such as rheumatoid arthritis and periodontitis-caused bone destruction, results from an increase of bone-resorbing osteoclasts (OCs) induced by inflammation. However, the detailed mechanisms underlying this disorder remain unclear. We herein investigated that the effect of urokinase-type plasminogen activator (uPA) on inflammatory osteoclastogenesis induced by lipopolysaccharide (LPS), which is a potent stimulator of bone resorption in inflammatory diseases. We found that the uPA deficiency promoted inflammatory osteoclastogenesis and bone loss induced by LPS. We also showed that LPS induced the expression of uPA, and the uPA treatment attenuated the LPS-induced inflammatory osteoclastogenesis of RAW264.7 mouse monocyte/macrophage lineage cells. Additionally, we showed that the uPA-attenuated inflammatory osteoclastgenesis is associated with the activation of plasmin/protease-activated receptor (PAR)-1 axis by uPA. Moreover, we examined the mechanism underlying the effect of uPA on inflammatory osteoclastogenesis, and found that uPA/plasmin/PAR-1 activated the adenosine monophosphate-activated protein kinase (AMPK) pathway through Ca2+/calmodulin dependent protein kinase kinase (CaMKK) activation, and attenuated inflammatory osteoclastogenesis by inactivation of NF-κB in RAW264.7 cells. These data suggest that uPA attenuated inflammatory osteoclastogenesis through the plasmin/PAR-1/Ca2+/CaMKK/AMPK axis. Our findings may provide a novel therapeutic approach to bone loss caused by inflammatory diseases. 相似文献
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Efficient modification of the myostatin gene in porcine somatic cells and generation of knockout piglets 下载免费PDF全文
28.
Murakami Shinsuke Nakatani Jun Nakajima Kenichi Amasawa Eri Ii Ryota Hayashi Kiyotada Yoshikawa Naoki Daigo Ichiro Kishita Yusuke Ihara Tomohiko Shobatake Koichi Kudoh Yuki Motoshita Masaharu Kanemoto Keiichiro Hara Minako Kashiwagi Aiichiro Hashimoto Seiji Shigetomi Yosuke Kanzaki Masayuki Kikuchi Yasunori Ohno Hajime Fukushima Yasuhiro 《The International Journal of Life Cycle Assessment》2019,24(8):1544-1552
The International Journal of Life Cycle Assessment - 相似文献
29.
Koyama Satoshi Fujita Hiroyuki Shimosato Takeshi Kamijo Aki Ishiyama Yasufumi Yamamoto Eri Ishii Yoshimi Hattori Yukako Hagihara Maki Yamazaki Etsuko Tomita Naoto Nakajima Hideaki 《Probiotics and antimicrobial proteins》2019,11(1):295-298
Probiotics and Antimicrobial Proteins - Probiotic-rich foods are consumed without much restriction. We report here, a case of septic shock caused by yogurt derived Lactobacillus species in a... 相似文献
30.
Oral treponemes are members of the spirochete family of bacteria associated with periodontal diseases. In the present study, we demonstrate that intercellular adhesion molecule-1 (ICAM-1) on human gingival epithelial cells (HGEC) contributed to the invasion of Treponema medium, a medium-sized oral Treponema, into those cells. The quantity of T. medium in HGEC was found to peak at 2 h after inoculation and then decreased gradually. Immunofluorescence microscopy findings showed that the bacteria were colocalized with ICAM-1 on HGEC. Furthermore, knockdown of ICAM-1 in HGEC resulted in inhibition of T. medium invasion by RNA interference, whereas that of Toll-like receptor 2 did not. These results suggest that ICAM-1 may be required for the invasion of T. medium into HGEC, and they indicate that the molecule plays a principal role in the primary stages of the development and progression of chronic periodontitis. 相似文献