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41.
42.
Improved polyhydroxybutyrate (PHB) production in transgenic tobacco by enhancing translation efficiency of bacterial PHB biosynthetic genes 总被引:1,自引:0,他引:1
Matsumoto K Morimoto K Gohda A Shimada H Taguchi S 《Journal of Bioscience and Bioengineering》2011,111(4):485-488
Polyhydroxybutyrate [P(3HB)] was produced in the transgenic tobacco harboring the genes encoding acetoacetyl-CoA reductase (PhaB) and polyhydroxyalkanoate synthase (PhaC) from Ralstonia eutropha (Cupriavidus necator) with optimized codon usage for expression in tobacco. P(3HB) contents in the transformants (0.2mg/g dry cell weight in average) harboring the codon-optimized phaB gene was twofold higher than the control transformants harboring the wild-type phaB gene. The immunodetection revealed an increased production of PhaB in leaves, indicating that the enhanced expression of PhaB was effective to increase P(3HB) production in tobacco. In contrast, codon-optimization of the phaC gene exhibited no apparent effect on P(3HB) production. This result suggests that the efficiency of PhaB-catalyzed reaction contributed to the flux toward P(3HB) biosynthesis in tobacco leaves. 相似文献
43.
Sato H. Wada T. Ohbayashi S. Kozaru K. Okamoto Y. Higashide Y. Shimizu T. Maki Y. Morimoto R. Otoi H. Koga T. Honda H. Taniguchi M. Arita Y. Shiomi T. 《Solid-State Circuits, IEEE Journal of》1999,34(11):1571-1579
This paper describes a 0.25-μm, 64 K×36 bit pipelined burst SRAM using a 6.156-μm2 cell. It realizes over 500-MHz operation using a lower cost double metal process, Internal 16 K×144 organization by T-shaped bit line array reduces 20% of latency, 20% of active power, and 8.5% of die size. The low power also enables us to use lower cost thin quad flat type packages. Our solution to the soft error problem, a shallow triple well structure and four-transistor cell with stacked capacitor, improved soft error rate by 3.5 orders of magnitude compared with the conventional SRAM cell 相似文献
44.
Sumio Chono Yoshihiko Tauchi Kazuhiro Morimoto 《Drug development and industrial pharmacy》2013,39(1):125-135
ABSTRACTIn order to confirm the efficacy of liposomes as a drug carrier for atherosclerotic therapy, the influence of particle size on the distribution of liposomes to atherosclerotic lesions in mice was investigated. In brief, liposomes of three different particle sizes (500, 200, and 70 nm) were prepared, and the uptake of liposomes by the macrophages and foam cells in vitro and the biodistributions of liposomes administered intravenously to atherogenic mice in vivo were examined. The uptake by the macrophages and foam cells increased with the increase in particle size. Although the elimination rate from the blood circulation and the hepatic and splenic distribution increased with the increase in particle size in atherogenic mice, the aortic distribution was independent of the particle size. The aortic distribution of 200 nm liposomes was the highest in comparison with the other sizes. Surprisingly, the aortic distribution of liposomes in vivo did not correspond with the uptake by macrophages and foam cells in vitro. These results suggest that there is an optimal size for the distribution of liposomes to atherosclerotic lesions. 相似文献
45.
Takashi Wakuda Kazuo Azuma Hiroyuki Saimoto Shinsuke Ifuku Minoru Morimoto Ichiro Arifuku Masahito Asaka Takeshi Tsuka Tomohiro Imagawa Yoshiharu Okamoto Tomohiro Osaki Saburo Minami 《Journal of Functional Foods》2013,5(1):516-523
The effects of pear vinegar (PV), which was specially brewed for enhanced galacturonic acid content, on the DSS-induced ulcerative colitis (UC) mouse model were evaluated. PV improved clinical symptoms, colon inflammation, and histological tissue injury in the DSS-induced acute UC mouse model. Moreover, PV suppressed inflammation due to acute UC by suppressing the myeloperoxidase (MPO)-mediated activation of inflammatory cells such as leukocytes and decreasing the serum concentration of IL-6. Our results demonstrated the protective action of PV in the DSS-induced acute UC mouse model. On the other hand, commercial apple vinegar did not show a protective effect in the DSS-induced acute UC mouse model. Our findings indicate that PV may act as a new functional food for inflammatory bowel disease patients. 相似文献
46.
M Otsuki K Hashimoto Y Morimoto T Kishimoto S Kasayama 《Canadian Metallurgical Quarterly》1997,46(12):2096-2101
Vascular cell adhesion molecule-1 (VCAM-1) has been shown to be highly expressed in atherosclerotic lesions. Although the soluble form of VCAM-1 (sVCAM-1) is detected in human sera, the relation between the degree of atherosclerosis and serum sVCAM-1 level has not been defined. In the present study, sVCAM-1 concentrations were measured in sera from 101 Japanese NIDDM patients. The mean +/- SD serum sVCAM-1 concentration in 26 patients with symptomatic atherosclerotic vascular diseases (789 +/- 187 ng/ml) was higher than that in 75 patients without the disease (664 +/- 175 ng/ml). Among the 101 NIDDM patients, 56 had atherosclerotic change of the carotid arteries, based on the evaluation by high-resolution B-mode ultrasonography. Their sVCAM-1 level was 759 +/- 201 ng/ml, higher than that in 45 patients without any detectable atherosclerosis of the carotid arteries (619 +/- 130 ng/ml). In addition, there was a positive correlation between sVCAM-1 concentration and thickness of the intimal plus medial complex (IMT) of the carotid arteries in the NIDDM patients (r = 0.41, P < 0.0001). Multivariate regression analysis revealed significant predictors of mean IMT value to be sVCAM-1 concentration (F = 62.88, P = 0.0001) and age (F = 9.59, P = 0.0026). By contrast, sVCAM-1 concentration was not increased in nondiabetic patients with atherosclerotic change of the carotid arteries (668 +/- 191 ng/ml; n = 36) compared with those without the atherosclerotic change (632 +/- 177 ng/ml; n = 28), and there was no correlation between sVCAM-1 level and IMT of the carotid arteries in the nondiabetic subjects. These results indicate that circulating sVCAM-1 may be a marker of atherosclerotic lesions in NIDDM patients with symptomatic and asymptomatic atherosclerosis. 相似文献
47.
S Koizumi M Ishiguro I Ohsawa T Morimoto C Takamura K Inoue S Kohsaka 《Canadian Metallurgical Quarterly》1998,123(8):1483-1489
1. The effects of secreted forms of beta-amyloid-precursor proteins (APP(S)s) on the intracellular Ca2+ concentration ([Ca2+]i) were investigated in rat cultured hippocampal neurones. APP695S, a secretory form of APP695, attenuated the increase in [Ca2+]i evoked by glutamate. In addition, APP695S itself evoked an increase in [Ca2+]i in 1 or 2 day-cultured hippocampal cells, but not in 7 to 13 day-cultured cells. 2. Eighty-one percent of neurones which were immunocytochemically positive for microtubule-associated protein 2 responded to APP695S with an increase in [Ca2+]i. 3. APP695S induced a transient rise in [Ca2+]i even in the absence of extracellular Ca2+ and produced an elevation in inositol-1,4,5-trisphosphate (IP3) in a concentration-dependent manner from 100 to 500 ng ml(-1). In the presence of extracellular Ca2+, APP695S caused a transient rise in [Ca2+]i followed by a sustained phase at high [Ca2+]i, suggesting Ca2+ entry from the extracellular space. 4. The [Ca2+]i elevation was mimicked by amino terminal peptides of APPs, but not by carboxy terminal peptides. 5. These results taken together suggest that APP695S induces an increase in [Ca2+]i in hippocampal neurones through an IP3-dependent mechanism that changes according to the stage of development. 相似文献
48.
H Sawada H Morimoto A Wake Y Yamasaki Y Izumi M Kuroiwa S Osabe Y Imamura K Egami A Tsukamoto I Sanada T Kiyokawa F Kawano 《Canadian Metallurgical Quarterly》1998,39(11):1085-1091
Thirty patients (median age of 32 years; range, 6-61) with hematologic disorders received unmanipulated peripheral blood stem cell transplants from HLA-matched or one-antigen-mismatched related donors following myeloablative therapy for acute lymphoblastic leukemia (7), acute myelogenous leukemia (6), chronic myelogenous leukemia (8), myelodysplastic syndrome (3), or other disorders (6). Granulocyte colony stimulating factor (G-CSF) mobilized peripheral blood stem cells were collected from donors in 1 to 3 aphereses. The apheresis products contained mean counts of 11.3 x 10(8) (range, 3.8-17.2) nucleated cells/kg and 6.7 x 10(6) (range, 1.3-16.7) CD34+ cells/kg. Graft-versus-host-disease (GVHD) prophylaxis consisted of cyclosporin A plus methotrexate, or FK506 plus methotrexate. All patients received G-CSF following their transplant. Although 1 patient died of pneumonia 6 days after transplantation, the others demonstrated rapid engraftment. Median days to recovery to 500/microliter neutrophils and 20,000/microliter platelets were 13 (range, 8-21) and 14 (range, 1-23) days, respectively. The incidence of acute GVHD grade II-IV was 33%; chronic GVHD developed in 57% of the assessable patients. There were no episodes of graft failure or rejection. Nineteen patients (63%) were alive and in complete remission from 147 to 839 days following their transplant (median follow-up of 560 days). Further follow-up study will be required to assess the incidence of chronic GVHD and graft-versus-leukemia (GVL) effects. 相似文献
49.
The activation of latent transforming growth factor beta (L-TGFbeta) is essential for the action of TGFbeta, which, in turn, is involved in the regulation of expression of some progesterone-responsive genes. One mechanism by which TGFbeta is activated involves thrombospondin (TSP), a protein that binds extracellular proteins. Immunoreactive TSP (irTSP) protein and TSP-1 mRNA in myometrial tissues of ovulatory and pregnant women were localized by immunohistochemistry and in situ hybridization. IrTSP and TSP-1 mRNA were randomly distributed in myometrial smooth muscle cells of some, but not all, tissues of pregnant women at term before labor; but in some areas of most of these tissues, irTSP was intense and commonly localized extracellularly. Intense irTSP and TSP-1 mRNA in myocytes were more common in myometrium during labor. In myometrium from ovulatory women (n = 26), irTSP was localized primarily in vascular smooth muscle cells and was detected occasionally in scattered myocytes. Little TSP-1 mRNA was demonstrable by in situ hybridization in vessels or myocytes of myometrial tissue from ovulatory women (n = 7). By Northern analysis of total RNA, TSP-1 mRNA was detected in myometrial tissue of pregnant women and in human myometrial smooth muscle cells in culture. The levels of TSP-1 mRNA in myometrial tissues of pregnant women during labor (n = 18) were greater than those in myometrium at > 37 wk gestation before labor began (n = 25, p < 0.001). The ratios of TSP-1 to glyceraldehyde 3-phosphate dehydrogenase mRNAs in 3 myometrial tissues during oxytocin-induced labor were not statistically different from those in myometrium during spontaneous labor but were greater than those in myometrium before labor (p < 0.05). The level of TSP-1 mRNA in confluent human myometrial cells in culture was relatively high, was increased by treatment with fetal bovine serum, and was decreased by treatment with platelet-derived growth factor or activators of adenylyl cyclase or protein kinase C. Myometrial cells in culture constitute a useful model for studying the regulation of TSP-1 gene expression in human myometrium. 相似文献
50.
To clarify the mechanisms of intracellular induction of oxidative DNA damage, we have investigated the concentrations of intracellular reactive oxygen species and the amounts of 8-hydroxydeoxyguanosine (8OHdG), a mutagenic oxidative DNA damage, in human neutrophil-like cells, dimethylsulfoxide-differentiated HL60 (DMSO-HL60). We determined intracellular concentrations of hydrogen peroxide and superoxide by flow cytometry with dichlorofluorescein diacetate and hydroethidine, respectively. We determined the 8OHdG amounts with an electrochemical detector connected to HPLC after anaerobic sample processing. DMSO-HL60 releases superoxide upon stimulation with phorbol myristate acetate, and the released superoxide dismutates to hydrogen peroxide. Stimulation of DMSO-HL60 with 100 nM phorbol myristate acetate increased intracellular hydrogen peroxide, superoxide and 8OHdG (control). Addition of 1000 U/ml catalase decreased hydrogen peroxide (31.3% of control) and 8OHdG (20.3%). Addition of 100 U/ml SOD decreased superoxide (18.7%) and 8OHdG (41.6%). Addition of 1 mM deferoxamine decreased 8OHdG (30.4%), but increased hydrogen peroxide (129.6%). Addition of 200 microM 4-acetamido-4'- isothiocyanostilbene-2,2'-disulfonic acid decreased superoxide (59.9%) and 8OHdG (42.0%). Addition of 0.4% ethanol had no effect on superoxide concentration (102.2%), but tended to decrease hydrogen peroxide (83.5%) and 8OHdG (84.3%). Pretreatment of DMSO-HL60 with 0.1 mM FeSO4 increased 8OHdG (117.3%), but decreased hydrogen peroxide (75.8%). These findings indicate that the extracellularly released superoxide and hydrogen peroxide diffuse into the cell, but that such reactive oxygen species are not the direct molecules to induce 8OHdG. Our results suggest that 8OHdG is induced by the hydroxyl radical which is generated from intracellular hydrogen peroxide and superoxide-reduced Fe. 相似文献