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891.
Young Rae Ji Hei Jung Kim Dong Hun Yu Ki Beom Bae Seo Jin Park Si Jun Park Woo Young Jang Min-Cheol Kang Jain Jeong Yong Hun Sung Minjee Choi Taejun Park Taesun Park Jong Won Yun Hyun-Shik Lee Sanggyu Lee Myoung Ok Kim Zae Young Ryoo 《Biochemical and biophysical research communications》2014
Chronic hepatitis is a major cause of liver cancer, so earlier treatment of hepatitis might be reducing liver cancer incidence. Hepatitis can be induced in mice by treatment with Concanavalin A (Con A); the resulting liver injury causes significant CD4+ T cell activation and infiltration. In these T cells, Roquin, a ring-type E3 ubiquitin ligase, is activated. To investigate the role of Roquin, we examined Con A-induced liver injury and T cell infiltration in transgenic (Tg) mice overexpressing Roquin specifically in T cells. In Roquin Tg mice, Con A treatment caused greater increases in both the levels of liver injury enzymes and liver tissue apoptosis, as revealed by TUNEL and H&E staining, than wild type (WT) mice. Further, Roquin Tg mice respond to Con A treatment with greater increases in the T cell population, particularly Th17 cells, though Treg cell counts are lower. Roquin overexpression also enhances increases in pro-inflammatory cytokines, including IFN-γ, TNF-α and IL-6, upon liver injury. Furthermore, Roquin regulates the immune response and apoptosis in Con A induced hepatitis via STATs, Bax and Bcl2. These findings suggest that over-expression of Roquin exacerbates T-cell mediated hepatitis. 相似文献
892.
Deng-Liang Wang Yan-Ling Song Zhi Zhu Xi-Lan Li Yuan Zou Hai-Tao Yang Jiang-Jie Wang Pei-Sen Yao Ru-Jun Pan Chaoyong James Yang De-Zhi Kang 《Biochemical and biophysical research communications》2014
Epidermal growth factor receptor (EGFR/HER1/c-ErbB1), is overexpressed in many solid cancers, such as epidermoid carcinomas, malignant gliomas, etc. EGFR plays roles in proliferation, invasion, angiogenesis and metastasis of malignant cancer cells and is the ideal antigen for clinical applications in cancer detection, imaging and therapy. Aptamers, the output of the systematic evolution of ligands by exponential enrichment (SELEX), are DNA/RNA oligonucleotides which can bind protein and other substances with specificity. RNA aptamers are undesirable due to their instability and high cost of production. Conversely, DNA aptamers have aroused researcher’s attention because they are easily synthesized, stable, selective, have high binding affinity and are cost-effective to produce. In this study, we have successfully identified DNA aptamers with high binding affinity and selectivity to EGFR. The aptamer named TuTu22 with Kd 56 ± 7.3 nM was chosen from the identified DNA aptamers for further study. Flow cytometry analysis results indicated that the TuTu22 aptamer was able to specifically recognize a variety of cancer cells expressing EGFR but did not bind to the EGFR-negative cells. With all of the aforementioned advantages, the DNA aptamers reported here against cancer biomarker EGFR will facilitate the development of novel targeted cancer detection, imaging and therapy. 相似文献
893.
Bongkun Choi Soon-Suk Kang Sang-Wook Kang Bon-Hong Min Eun-Jin Lee Da-Hyun Song Sang-Min Kim Youngsup Song Seung-Yong Yoon Eun-Ju Chang 《Biochemical and biophysical research communications》2014
Secretory clusterin (sCLU)/apolipoprotein J is a multifunctional glycoprotein that is ubiquitously expressed in various tissues. Reduced sCLU in the joints of patients with bone erosive disease is associated with disease activity; however, its exact role has yet to be elucidated. Here, we report that CLU is expressed and secreted during osteoclastogenesis in mouse bone marrow-derived macrophages (BMMs) that are treated with receptor activator of nuclear factor kappa-B ligand (RANKL) and macrophage colony-stimulating factor (M-CSF). CLU-deficient BMMs obtained from CLU−/− mice exhibited no significant alterations in OC differentiation in comparison with BMMs obtained from wild-type mice. In contrast, exogenous sCLU treatment significantly inhibited OC formation in both BMMs and OC precursor cultures. The inhibitory effect of sCLU was more prominent in BMMs than OC precursor cultures. Interestingly, treating BMMs with sCLU decreased the proliferative effects elicited by M-CSF and suppressed M-CSF-induced ERK activation of OC precursor cells without causing apoptotic cell death. This study provides the first evidence that sCLU reduces OC formation by inhibiting the actions of M-CSF, thereby suggesting its protective role in bone erosion. 相似文献
894.
895.
896.
Juno Jang Sung-Hwan Hong Dongwon Choi Kang-Seuk Choi Seongman Kang Ik-Hwan Kim 《Applied microbiology and biotechnology》2010,85(5):1509-1520
Newcastle disease virus (NDV) is not only one of the most economically important pathogen of poultry but also has a potential
as anticancer virotherapy. The role of NDV V protein in virus-production kinetics was investigated using DF-1 cell-based production
system. The presence of an anti-interferon (IFN)-alpha antibody resulted in enhanced NDV production kinetics in a dose-dependent
manner by blocking binding of NDV-induced IFN to its receptor. To prepare DF-1 cell whose cellular IFN signaling is blocked
efficiently, stable cell lines expressing either lentogenic or velogenic NDV V protein known as an IFN antagonist were established.
The overexpression of NDV V protein enhanced NDV production kinetics and expedited the rate of NDV production, while it had
no effect on Japanese encephalitis virus production. NDV V protein functions as an IFN antagonist by inhibiting the increase
in type I IFNs by NDV infection. The IFN signals in cells expressing NDV V protein were weakened by decreased activation or
expression of the dsRNA-activated enzymes. These IFN antagonist activities enhance rapid virus replication and spread in the
early phase of viral infection and will be useful in improving the production of viral vaccine strains. 相似文献
897.
Choong Hyun Lee Jung Hoon Choi Ki-Yeon Yoo Ok Kyu Park In Koo Hwang Sang Guan You Boo-Yong Lee Il-Jun Kang Moo-Ho Won 《Cellular and molecular neurobiology》2010,30(2):255-263
Melatonin exerts many physiological functions via its G protein-coupled receptors. In the present study, we investigated age-related
changes in MT2 melatonin receptor immunoreactivity and its levels in the gerbil hippocampus during normal aging. In the postnatal
month 1 (PM 1) group, MT2 immunoreaction was well observed in neurons in all subregions of the gerbil hippocampus. In the
PM 3 and 6 groups, MT2 immunoreactivity in neurons was decreased compared to that in the PM 1 group. Thereafter, MT2 immunoreactivity
in neurons was increased. In the PM 18 and 24 groups, MT2 immunoreactivity in neurons was strong in all subregions of the
gerbil hippocampus. In addition, the number of MT2 immunoreactive cells was lowest at PM 3 and highest at PM 24. From western
blot analysis, age-dependent change pattern in MT2 level in the gerbil hippocampus was similar to the immunohistochemical
result. These results indicate that MT2 immunoreactivity and levels are altered in the gerbil hippocampus during normal aging;
lowest at young adult stage and highest at aged stage. 相似文献
898.
Wei Yi Yang Sun Xufeng Wei Chunhu Gu Xiaochao Dong Xiaojun Kang Shuzhong Guo Kefeng Dou 《Molecular and cellular biochemistry》2010,337(1-2):9-16
Diets containing 8% salt or 4% fructose (FR) cause insulin resistance and increase tissue methylglyoxal and advanced glycation end products (AGEs), platelet cytosolic-free calcium, and systolic blood pressure (SBP) in rats. In WKY rats, we have shown that moderately high salt, 4% NaCl (MHS) alone in diet does not cause hypertension, and when given along with 4% FR it does not have an additive effect. N-acetylcysteine (NAC) or l-arginine (ARG), treatment alone does not prevent hypertension in this model. The objectives of this study were to investigate the effect of NAC plus ARG in diet on SBP, platelet cytosolic-free calcium in a MHS + FR model, and to measure the plasma levels of methylglyoxal and the AGE, methylglyoxal-derived hydroimidazolone (MGH). At 7 weeks of age, WKY rats were divided into three groups: control group was given regular rat chow (0.7% NaCl) and water; MHS + FR group, diet containing 4% NaCl and 4% FR in drinking water; and MHS + FR + NAC + ARG group, MHS diet supplemented with 1.5% N-acetylcysteine (NAC) and 1.5% l-arginine (ARG), and 4% FR in drinking water, and followed for 6 weeks. NAC + ARG prevented the increase in platelet cytosolic-free calcium and SBP in MHS + FR treated rats. There was no difference in mean values of plasma methylglyoxal and MGH among the groups. In conclusion, NAC + ARG treatment is effective in preventing hypertension in a moderately high salt + FR-induced animal model. Plasma methylglyoxal and MGH may not represent tissue modification or, alternatively, other tissue AGEs, derived from methylglyoxal or other aldehydes, may be involved in hypertension in this model. 相似文献
899.
900.
Min-Jung Kang Chul-Hwan Lee Young-Hoon Kang Il-Taeg Cho Tuan Anh Nguyen Yeon-Soo Seo 《Nucleic acids research》2010,38(21):7611-7625
The two endonucleases, Rad27 (yeast Fen1) and Dna2, jointly participate in the processing of Okazaki fragments in yeasts. Mus81–Mms4 is a structure-specific endonuclease that can resolve stalled replication forks as well as toxic recombination intermediates. In this study, we show that Mus81–Mms4 can suppress dna2 mutational defects by virtue of its functional and physical interaction with Rad27. Mus81–Mms4 stimulated Rad27 activity significantly, accounting for its ability to restore the growth defects caused by the dna2 mutation. Interestingly, Rad27 stimulated the rate of Mus81–Mms4 catalyzed cleavage of various substrates, including regressed replication fork substrates. The ability of Rad27 to stimulate Mus81–Mms4 did not depend on the catalytic activity of Rad27, but required the C-terminal 64 amino acid fragment of Rad27. This indicates that the stimulation was mediated by a specific protein–protein interaction between the two proteins. Our in vitro data indicate that Mus81–Mms4 and Rad27 act together during DNA replication and resolve various structures that can impede normal DNA replication. This conclusion was further strengthened by the fact that rad27 mus81 or rad27 mms4 double mutants were synergistically lethal. We discuss the significance of the interactions between Rad27, Dna2 and Mus81–Mms4 in context of DNA replication. 相似文献