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991.
992.
Ikumi Katano Ryoji Ito Tsutomu Kamisako Tomoo Eto Tomoyuki Ogura Kenji Kawai Hiroshi Suemizu Takeshi Takahashi Yutaka Kawakami Mamoru Ito 《Experimental Animals》2014,63(3):321-330
We have developed NOD-Rag2null IL-2Rγnull (NR2G)
mice similar to NOD-scidIL-2Rγnull (NOG) mice
that are known as an excellent host to generate humanized mice. To evaluate the usefulness
of NR2G mice as a host for humanized mice, the engraftment rates and differentiation of
human cells after human hematopoietic stem cell (HSC) transplantation were compared among
NR2G, NOG, and NOD-scid mice. For this purpose, the appropriate
irradiation doses to expand the niche for human stem cells in the bone marrow were first
determined. As a result, 8 and 2.5 Gy in adult, and 4 and 1 Gy in newborn NR2G and NOG
mice, respectively, were found to be appropriate. Next, 5 × 104 human umbilical
cord blood CD34+ cells were intravenously inoculated into irradiated adult or
newborn of the immunodeficient mice. These HSC transplantation experiments demonstrated
that both NR2G and NOG mice showed high engraftment rates compared with
NOD-scid mice, although NOG mice showed a slightly higher engraftment
rate than that for NR2G mice. However, no difference was found in the human cell
populations differentiated from HSCs between NR2G and NOG mice. The HSC transplantation
experiments to adults and newborns of two immunodeficient mice also revealed that the HSC
transplantation into newborn mice resulted in higher engraftment rate than those into
adults. These results showed that NR2G mice could be used as an alternative host to NOG
mice to generate humanized mice. 相似文献
993.
Jun Fujii Maho Kodama Akira Oike Yasuki Matsuo Mi-Sook Min Takashi Hasebe Atsuko Ishizuya-Oka Koichi Kawakami Masahisa Nakamura 《PloS one》2014,9(5)
In mice and humans, the androgen receptor (AR) gene, located on the X chromosome, is not known to be involved in sex determination. In the Japanese frog Rana rugosa the AR is located on the sex chromosomes (X, Y, Z and W). Phylogenetic analysis shows that the AR on the X chromosome (X-AR) of the Korean R. rugosa is basal and segregates into two clusters: one containing W-AR of Japanese R. rugosa, the other containing Y-AR. AR expression is twice as high in ZZ (male) compared to ZW (female) embryos in which the W-AR is barely expressed. Higher AR-expression may be associated with male sex determination in this species. To examine whether the Z-AR is involved in sex determination in R. rugosa, we produced transgenic (Tg) frogs carrying an exogenous Z-AR. Analysis of ZW Tg frogs revealed development of masculinized gonads or ‘ovotestes’. Expression of CYP17 and Dmrt1, genes known to be activated during normal male gonadal development, were up-regulated in the ZW ovotestis. Testosterone, supplied to the rearing water, completed the female-to-male sex-reversal in the AR-Tg ZW frogs. Here we report that Z-AR is involved in male sex-determination in an amphibian species. 相似文献
994.
995.
Ai Haraguchi Naomi Hayashida Toshihiko Kamasaki Izumi Miyamoto Toshiya Usui Takao Ando Norio Abiru Hironori Yamasaki Kenya Chiba Takashi Kudo Atsushi Kawakami Noboru Takamura 《PloS one》2014,9(11)
Objective
This study investigated the relationship between aortic 18F-fluoro-2-deoxy-D-glucose (18F-FDG) uptake and clinical and laboratory findings related to atherosclerosis in a general population.Methods
18F-FDG uptake in the ascending aorta was measured on the positron emission tomography/computed tomography (PET/CT) scans of 211 Japanese adults. The maximum target-to-background ratio (TBR) was compared with clinical and laboratory atherosclerosis findings.Results
By multivariate regression analysis adjusted for age and sex, TBR-ascending aorta (TBR-A) was significantly correlated with various clinical and laboratory parameters, such as body mass index, log visceral fat area, low-density lipoprotein cholesterol (LDL-C), log fasting immunoreactive insulin, log homeostasis model assessment of insulin resistance, log total adiponectin and log-leptin, in all subjects. Furthermore, by multivariate linear regression analysis adjusted for confounding factors, TBR-A was significantly correlated with LDL-C (β = 0.001, p = 0.03) and log-leptin (β = 0.336, p<0.01) in all subjects.Conclusion
TBR-A was significantly correlated with LDL-C and log-leptin independent from confounding factors. Our results suggest that aortic 18F-FDG uptake is a good marker of atherosclerosis, even in a general population. 相似文献996.
Yasumi Uchida Yasuto Uchida Ei Shimoyama Nobuyuki Hiruta Toshihiko Kishimoto Soichiro Watanabe 《PloS one》2016,11(3)
Objectives
It is generally believed that low-density lipoprotein enters the vascular wall from its lumen and oxidized (oxLDL), after which it plays an important role in atherosclerosis. Because voluminous epicardial adipose tissue is a risk factor for coronary events, there is a possibility that the pericoronary adipose tissue (PCAT), which is a part of epicardial adipose tissue, acts as a risk factor by supplying oxLDL to the coronary arterial wall. The present study was performed whether PCAT stores and supplies oxLDL to the coronary wall.Methods
Localization of oxLDL in PCAT and its relation to plaque morphology were examined by immunohistochemical techniques in 27 epicardial coronary arteries excised from 9 human autopsy cases.Results
OxLDL deposited in all PCAT of the studied cases. The percent (%) incidence of oxLDL in the intima of 25 normal segment, 19 white plaques, 15 yellow plaques without necrotic core (NC) and 10 yellow plaques with NC, was 32, 84, 93 (p<0.05 vs normal segments and yellow plaques with NC), and 30, respectively. OxLDL deposited either in dotted or diffuse pattern. Double immunohistochemical staining revealed that the dotted oxLDL was that contained in CD68(+)-macrophages. The oxLDL-containing macrophages were observed in the interstitial space but not inside of the vasa vasorum, and they traversed PCAT, adventitia, external and internal elastic laminae, suggesting their migration towards the intima. Diffuse oxLDL deposits were observed in 17 preparations, the majority of which were co-localized with the vasa vasorum in outer or in both inner and outer halves of intima, and rarely in the inner half alone.Conclusions
The results suggested that PCAT is a supply source of oxLDL to coronary intima and acts as a risk factor for coronary events, that oxLDL increasingly deposits in the intima with plaque growth and decreases after plaque maturation, and therefore molecular therapies targeting the PCAT before plaque growth could be effective in preventing human coronary atherosclerosis. 相似文献997.
Yoshimasa Nakamura Makiko Kawakami Akira Yoshihiro Noriyuki Miyoshi Hajime Ohigashi Kiyoshi Kawai Toshihiko Osawa Koji Uchida 《The Journal of biological chemistry》2002,277(10):8492-8499
In the present study, we studied the molecular mechanism underlying cell death induced by a cancer chemoprotective compound benzyl isothiocyanate (BITC). The cytotoxic effect of BITC was examined in rat liver epithelial RL34 cells. Apoptosis was induced when the cells were treated with 20 mum BITC, characterized by the appearance of phosphatidylserine on the outer surface of the plasma membrane and caspase-3 activation, whereas no caspase activation and propidium iodide incorporation into cell were detected with 50 mum BITC that induced necrosis. The mitochondrial death pathway was suggested to be involved in BITC-induced apoptosis because the treatment of cells with BITC-induced caspase-9-dependent apoptosis and mitochondrial transmembrane potential (Delta Psi m) alteration. We demonstrated here for the first time that BITC directly modifies mitochondrial functions, including inhibition of respiration, mitochondrial swelling, and release of cytochrome c. Moreover, glutathione depletion by diethyl maleate significantly accelerated BITC-triggered apoptosis, suggesting the involvement of a redox-dependent mechanism. This was also implicated by the observations that intracellular accumulation of reactive oxygen species, including superoxide (O(2)) and hydroperoxides (HPOs), was indeed detected in the cells treated with BITC and that the intracellular HPO level was significantly attenuated by pretreatment with N-acetylcysteine. The treatment with a pharmacological scavenger of O(2), Tiron, also diminished the HPO formation by approximately 80%, suggesting that most of the HPOs were H(2)O(2) derived from the dismutation of O(2). These results suggest that BITC induces apoptosis through a mitochondrial redox-sensitive mechanism. 相似文献
998.
We have isolated cDNA molecules representing the complete coding sequence of a new human gene which is a member of the src family of oncogenes. Nucleotide sequence analysis revealed that this gene, termed slk, encoded a 537-residue protein which was 86% identical to the chicken proto-oncogene product, p60c-src, over a stretch of 191 amino acids at its carboxy terminus. In contrast, only 6% amino acid homology was observed within the amino-terminal 82 amino acid residues of these two proteins. It was possible to activate slk as a transforming gene by substituting approximately two-thirds of the slk coding sequence for an analogous region of the v-fgr onc gene present in Gardner-Rasheed feline sarcoma virus. The resulting hybrid protein molecule expressed in transformed cells demonstrated protein kinase activity with specificity for tyrosine residues. 相似文献
999.
Daisuke Asaoka Akihito Nagahara Takeshi Matsuhisa Shin‐ichi Takahashi Kengo Tokunaga Takashi Kawai Kohei Kawakami Hidekazu Suzuki Masayuki Suzuki Toshihiro Nishizawa Naoto Kurihara Masayoshi Ito Hitoshi Sasaki Fumio Omata Shigeaki Mizuno Akira Torii Toshifumi Ohkusa Tetsuya Mine Nobuhiro Sakaki 《Helicobacter》2013,18(6):468-472
1000.
Evidence for horizontal transfer of the EcoT38I restriction-modification gene to chromosomal DNA by the P2 phage and diversity of defective P2 prophages in Escherichia coli TH38 strains
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A DNA fragment carrying the genes coding for a novel EcoT38I restriction endonuclease (R.EcoT38I) and EcoT38I methyltransferase (M.EcoT38I), which recognize G(A/G)GC(C/T)C, was cloned from the chromosomal DNA of Escherichia coli TH38. The endonuclease and methyltransferase genes were in a head-to-head orientation and were separated by a 330-nucleotide intergenic region. A third gene, the C.EcoT38I gene, was found in the intergenic region, partially overlapping the R.EcoT38I gene. The gene product, C.EcoT38I, acted as both a positive regulator of R.EcoT38I gene expression and a negative regulator of M.EcoT38I gene expression. M.EcoT38I purified from recombinant E. coli cells was shown to be a monomeric protein and to methylate the inner cytosines in the recognition sequence. R.EcoT38I was purified from E. coli HB101 expressing M.EcoT38I and formed a homodimer. The EcoT38I restriction (R)-modification (M) system (R-M system) was found to be inserted between the A and Q genes of defective bacteriophage P2, which was lysogenized in the chromosome at locI, one of the P2 phage attachment sites observed in both E. coli K-12 MG1655 and TH38 chromosomal DNAs. Ten strains of E. coli TH38 were examined for the presence of the EcoT38I R-M gene on the P2 prophage. Conventional PCR analysis and assaying of R activity demonstrated that all strains carried a single copy of the EcoT38I R-M gene and expressed R activity but that diversity of excision in the ogr, D, H, I, and J genes in the defective P2 prophage had arisen. 相似文献