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排序方式: 共有585条查询结果,搜索用时 15 毫秒
1.
2.
Kei Watanabe Kenta Wada Tomoko Ohashi Saki Okubo Kensuke Takekuma Ryoichi Hashizume Jun-Ichi Hayashi Tadao Serikawa Takashi Kuramoto Yoshiaki Kikkawa 《PloS one》2012,7(11)
We discovered a new cataract mutation, kfrs4, in the Kyoto Fancy Rat Stock (KFRS) background. Within 1 month of birth, all kfrs4/kfrs4 homozygotes developed cataracts, with severe opacity in the nuclei of the lens. In contrast, no opacity was observed in the kfrs4/+ heterozygotes. We continued to observe these rats until they reached 1 year of age and found that cataractogenesis did not occur in kfrs4/+ rats. To define the histological defects in the lenses of kfrs4 rats, sections of the eyes of these rats were prepared. Although the lenses of kfrs4/kfrs4 homozygotes showed severely disorganised fibres and vacuolation, the lenses of kfrs4/+ heterozygotes appeared normal and similar to those of wild-type rats. We used positional cloning to identify the kfrs4 mutation. The mutation was mapped to an approximately 9.7-Mb region on chromosome 7, which contains the Mip gene. This gene is responsible for a dominant form of cataract in humans and mice. Sequence analysis of the mutant-derived Mip gene identified a 5-bp insertion. This insertion is predicted to inactivate the MIP protein, as it produces a frameshift that results in the synthesis of 6 novel amino acid residues and a truncated protein that lacks 136 amino acids in the C-terminal region, and no MIP immunoreactivity was observed in the lens fibre cells of kfrs4/kfrs4 homozygous rats using an antibody that recognises the C- and N-terminus of MIP. In addition, the kfrs4/+ heterozygotes showed reduced expression of Mip mRNA and MIP protein and the kfrs4/kfrs4 homozygotes showed no expression in the lens. These results indicate that the kfrs4 mutation conveys a loss-of-function, which leads to functional inactivation though the degradation of Mip mRNA by an mRNA decay mechanism. Therefore, the kfrs4 rat represents the first characterised rat model with a recessive mutation in the Mip gene. 相似文献
3.
Tatsuo Nakahara Makoto Hirano Takashi Matsumoto Toshihide Kuroki Yoshinori Tatebayashi Tetsuyuki Tsutsumi Kouji Nishiyama Hiroaki Ooboshi Kaoru Nakamura Hiroshi Yao Akio Shiraishi Michinori Waki Hideyuki Uchimura 《Neurochemical research》1990,15(6):609-611
DNA and RNA contents in 20 brain regions or nuclei of the rat were determined by a highly sensitive method using high-performance liquid chromatography with electrochemical detection. The high DNA and RNA contents were found in the hypothalamic nuclei, especially the median eminence-arcuate nucleus. These results may be available for the preparation of nucleic acids as the regional control. 相似文献
4.
The efficacy of Sizofiran(SPG), a highly purified -1,3-D-glucan from the culture broth of a basidiomycetesSchizophyllum commune Fries, in combination with local irradiation was investigated using squamous-cell carcinoma NR-S1 and syngeneic hosts of OH/He mice. NR-S1 tumor was implanted sc in the thigh of C3H/He mice. When tumor grew to 4 mm in diameter, the local irradiation of 55 Gy was delivered. SPG was injected im at a dose of 5 mg/kg. When SPG was administered after irradiation, remarkable inhibition of tumor growth was observed in comparison with the radiation alone group. Furthermore, the combination effect of radiation and active immunotherapy using mitomycin C-treated NR-S1 cells as vaccine was examined. When radiotherapy and active immunotherapy were combined with SPG, suppression of tumor growth was observed from an early stage in comparison with the group which was not administered SPG. SPG also inhibited the pulmonary metastasis of NR-S1 tumor after radiotherapy. 相似文献
5.
The effect of a stressful manipulation on the metabolism of gamma-aminobutyric acid (GABA) in the rat brain was studied. Application of an immobilized stress to animals induced a significant increase in the striatal and hypothalamic GABA contents without affecting those in other central structures examined. It was also found that the increase in striatal GABA level preceded that in the hypothalamus. This increase in steady-state levels of GABA in the striatum and hypothalamus disappeared at 12 h after the termination of the application of stress for 3 h, which exhibited a maximal stimulatory action on the GABA contents in both central areas. The activity of L-glutamic acid decarboxylase was found to be significantly elevated in the striatum and hypothalamus following the stress application with a concomitant decrease in the content of L-glutamic acid, which is converted to GABA by the catalytic action of the latter enzyme. The in vivo turnover of GABA in the brain was estimated by taking advantages of the postmortem accumulation of GABA following decapitation and of the selective inhibitory action of a low dose of aminooxyacetic acid on the GABA degrading system, respectively. Analysis using these two different methods revealed that the cerebral turnover of GABA in vivo was not significantly altered under stressful situations despite of the increase in its steady-state level. These results suggest that central GABA system may respond to the input of painful stimuli resulting from the application of a severe physical and psychological stressor, in addition to the well-known functional alterations in catecholamine neurons. The functional significance of these alterations in the central GABA neurons is also discussed. 相似文献
6.
Noriko Usui Kouji Matsushima Anne M. Pilaro Dan L. Longo Robert H. Wiltrout 《Biotherapy》1996,9(4):199-208
Recombinant human interleukin 1α (rh IL-1α) and etoposide (VP-16) synergize for direct growth inhibition of several human
tumor cell linesin vitro. Our previous studies demonstrated that VP-16 increased the number of membrane-associated IL-1 receptors (IL-1Rs) and also
enhanced the internalization of receptor-bound rh IL-1α. The purposes of this study were to test our hypothess that these
events were critical to the synergy between rhIL-1α and VP-16, to determine whether rhIL-1α and VP-16 synergize to increase
superoxide (SO) anion radical productionin vitro since SO anion has been implicated in the toxic effects of IL-1, and to investigate the antitumor efficacy of the combinaton
against tumors in vivo. A375/C6 melanoma cells and OVCAR-3 ovarian carcinoma cells were tested with IL-1 receptor antagonist
(IL-1ra) before exposure to rhIL-1α, VP-16 and rhIL-1α plus VP-16. The synergistic or antagonistic effects were assessed by
MTT assay. SO production was measured by reduction of cytochrome C. Athymic female mice bearing the A375/C6 melanoma were
treated by rhIL-1α, VP-16, and rhIL-1α+VP-16. The antitumor effects were evaluated by quantitating tumor growth and survival
time. Pretreatment with the IL-1ra abrogated the synergistic effects of rhIL-1α and VP-16. The production of SO radical by
A375/C6 cells was increased 2.5 fold by the combination of rhIL-1α and VP-16, and the addition of exogenous SOD blocked the
synergy between rhIL-1α and VP-16. However, when A375/S0D15 cells which over-expressed manganese superoxide dismutase (MnSOD)
after MnSOD cDNA transfecton were exposed to rhIL-1α and VP-16, in vitro antagonism was observed. In vivo studies demonstrated
that the combination of rhIL-1α and VP-16 delayed tumor growth better than either agent alone, although long-term survival
was not improved because of substantial toxicity. Our results suggest that the synergistic antitumor effects of IL-1α and
VP-16 may be due to IL-1R modulation and increased internalization of IL-1-IL-1R complex by VP-16 treatment, as well as to
a subsequent increase in SO anion radical production from the tumor cells exposed to both drugs. Thus, the combnation of IL-1α
and VP-16 might prove useful for the treatment of malignant diseasein vivo, if the increased toxicity can be reduced or managed.
The US Government’s right to retain a non-exclusive royalty-free license on and to any copyright is acknowledged. 相似文献
7.
Jianyu Zheng Kohei Irifune Kouji Hirai Masashi Nakata Ryuso Tanaka Hiromichi Morikawa 《Journal of plant research》1994,107(4):365-369
In situ hybridization with a biotin-labeled rice ribosomal DNA (rDNA) probe to the somatic metaphase chromosomes of six species ofPhaseolus andVigna (P. angularis, P. calcaratus, P. coccineus, P. vulgaris, V. sesquipedalis andV. sinensis) was done to determine the sites of rDNA. Hybridization signals were present in the terminal and subterminal chromosome regions
of each of the six species. The number of rDNA sites was two inP. angularis andP. calcaratus, four inP. coccineus andP. vulgaris, and six inV. sesquipedalis andV. sinensis. 相似文献
8.
9.
Noritsugu Yabe Kouji Komiya Tetsuya Takezono Hisao Matsui 《In vitro cellular & developmental biology. Animal》1993,29(10):795-806
Summary Lysozyme at 1 to 100μg/ml of exposure levels augmented or inhibited proliferative response of human peripheral blood lymphocytes stimulated with
interleukin-2 (IL-2). This contradictory effect of lysozyme depended on IL-2 concentration, activating state of lymphocytes,
addition time of lysozyme, and serum existence. Lymphocytes increased their IL-2-mediated proliferating ability in response
to lysozyme when stimulated with less than suboptimal concentration of IL-2. Lymphocyte activation with anti-CD3 antibody
changed the augmented proliferative response into the inhibited response by lysozyme addition whereas elimination of MHC class
II molecule-expressing cells augmented the response. Addition of lysozyme within 1 h after IL-2 exposure was most effective
in promoting the proliferation whereas additions after 16 to 24 h were ineffective or inhibitory. Addition after longer than
24 h inversely restored the proliferative response. Serum seemed to retard lysozyme action because either sequential serum
addition 1 h after exposure of IL-2 and lysozyme to cells or exposure of IL-2 and serum after pretreatment of cells with lysozyme
changed the proliferative responsiveness from inhibition into augmentation. Thus lysozyme may regulate lymphocyte proliferation
responding to a magnitude of antigenic stimuli and to the progression of cellular events that periodically occur. 相似文献
10.
Karasawa Takusato; Tabuchi Kouji; Fumoto Masaki; Yasukawa Tamio 《Bioinformatics (Oxford, England)》1993,9(3):243-251
A model system is proposed to simulate the folding processesof proteins during thermal annealing. This system consists offour subsystems: (i) the pearl necklace model with isotropicinter-residue interactions; (ii) the extended pearl necklacemodel with anisotropic interaction potentials; (iii) moltenglobule phase dynamics; and (iv) final generation of the three-dimensionalstructure of a given protein. In this paper results obtainedwith the pearl necklace model are reported. This model consistsof spherical elements and virtual bonds of 3.8 Å in lengthand is intended to sinudate dynamical processes at relativelyhigh temperature where entropic terms play a dominant role.Inter-residue interactions are composed of spherical soft repulsivepotentials and hydrophobic interactions inherent to respectiveresidues. A simulation of folding processes of BPTI startingfrom the fully extended conformation indicated that intermediates,even at early stages of folding, are not randomly coiled butassume organized structures that resemble, to some extent, thenative conformation. 相似文献