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971.
Pseudopropionibacterium rubrum sp. nov., a novel red‐pigmented species isolated from human gingival sulcus 下载免费PDF全文
Masanori Saito Noriko Shinozaki‐Kuwahara Osamu Tsudukibashi Tomomi Hashizume‐Takizawa Ryoki Kobayashi Tomoko Kurita‐Ochiai 《Microbiology and immunology》2018,62(6):388-394
972.
Partitioning of the F plasmid: Overproduction of an essential protein for partition inhibits plasmid maintenance 总被引:2,自引:0,他引:2
Noriko Kusukawa Hirotada Mori Akihiro Kondo Sota Hiraga 《Molecular & general genetics : MGG》1987,208(3):365-372
Summary Multicopy plasmids carrying the sopB gene of the F plasmid inhibit stable inheritance of a coexisting mini-F plasmid. This incompatibility, termed IncG, is found to be caused by excess amounts of the SopB protein, which is essential for accuratepartitioning of plasmid DNA molecules into daughter cells. A sopB-carrying multicopy plasmid that shows the IncG+ phenotype was mutagenized in vitro and IncG negative mutant plasmids were isolated. Among these amber and missense mutants of sopB, mutants with a low plasmid copy number and a mutant in the Shine-Dalgarno sequence for translation of the SopB protein were obtained. These results demonstrate that the IncG phenotype is caused by the SopB protein, and that the incompatibility is expressed only when the protein is overproduced. This suggests that the protein must be kept at appropriate concentrations to ensure stable maintenance of the plasmid. 相似文献
973.
Cell division synchrony was induced in tobacco {Nicotiana tabacum)cultured cells by several treatments. Very high synchrony throughouttwo cell cycles was induced by aphidicolin treatment (inhibitorof DNA polymerase , 10 µg/ml) and by treatment with lowtemperature (4°C) and hydroxyurea (50 µg/ml). Themitotic index reached its maximum (52% and 40% in aphidicolinand hydroxyurea treatments, respectively) at 11 h after removalof the added chemical. During the treatments, the cells werearrested in the G1/S phase of the cell cycle. In the aphidicolin-inducedsystem, incorporation of 14C-thymidine confirmed that DNA synthesiswas started immediately after removal of the chemical. The aphidicolin-induced synchronous cells were used to studythe contents of butanol-soluble cytokinins during the cell cycle.Cytokinin contents increased conspicuously at the G2/M boundary.
1Present address: Department of Biology, Otsuma Women's University,Chiyodaku, Tokyo 102, Japan. (Received May 14, 1985; Accepted November 8, 1985) 相似文献
974.
Takahiko Tanigawa Hisao Takayama Hitoshi Osatake Keiichi Tanaka Noriko Kasagi Yoshinori Tanaka 《Cytotechnology》1992,10(1):43-51
Characteristics of mouse macrophage (MP) cell lines A640-BB-2, J774.1 and P388D1 and mouse peritoneal exudate MPs were studied and compared in cell morphology, ability to recognize tumor cells in the presence and absence of OK-432 known to activate MPs, and in lysosomal enzyme activity. In A640-BB-2 cells and exudate MPs, cell surfaces showed a few ridge-like processes and microvilli; spontaneous cytotoxicity was moderate against tumor target L929, and little or absent against targets SV3T3, B-16 and U937; and lysosomal enzyme activity of nonspecific esterase, acid phosphatase, and -glucuronidase was high. After culture in the presence of OK-432, A640-BB-2 cells and exudate MPs showed more extensive spreading with larger surface areas and with increased numbers of ridge-like processes and microvilli, and their cytotoxicity against target L929 became more extensive. The stable soluble factor did not participate in the mechanism of cytotoxicity against target L929 mediated by A640-BB-2 cells and exudate MPs. J774.1 and P388D1 cells were different from exudate MPs in cell morphology and ability to recognize tumor cells when cultured either with or without OK-432, and in lysosomal enzyme activity. A640-BB-2 cells seem to be useful in studying MP-tumor cell interaction and MP activation, and in detecting the trace biological activating factor of MPs.Abbreviations DEM
Dulbecco's modified Eagle's medium
- MP
macrophage
- PBS
phosphate-buffered saline
- SEM
scanning electron microscopy 相似文献
975.
Nobushige Nishimoto Shiro Nakai Noriko Takagi Shinichi Hayashi Tsunematsu Takemoto Shizuo Odashima Haruhisa Kizu Yoshikazu Wada 《Phytochemistry》1984,23(1):139-142
Three new nortriterpene glucuronides named pfaffosides A, B and C have been isolated from roots of Pfaffia paniculata. Their structures have been established as 3β-O-[β-d-xylopyranosyl-(1→2)β-d-glucuronopyranosyl]-pfaffic acid, 3β-O-[β-d-xylopyranosyl-(1→2)-β-d-glucuronopyranosyl]-pfaffic acid-(28→1)-β-d-glucopyranosyl ester and 3β-O-[β-d-glucuronopyranosyl]-pfaffic acid-(28→ l)-β-d-glucopyranosyl ester, respectively, based on their chemical and spectroscopic properties. 相似文献
976.
Kazuo Mukai Noriko Tsuzuki Kazuhiko Ishizu Setsuhiro Ouchi Kenji Fukuzawa 《Chemistry and physics of lipids》1984,35(3):199-208
Electron spin resonance (ESR) and electron nuclear double resonance (ENDOR) measurements were performed for the cation radicals obtained from the model compounds of α-, β-, γ- and δ-tocopherol (vitamin E) by oxidizing the tocopherol precursors in an AlCl3-CH2Cl2 solution. The proton hyperfine coupling constants g-values were precisely determined. The ENDOR spectra of the cation radicals of α-, β-, γ- and δ-tocopherol models in CH2Cl2 at ?100°C clearly show 10, 6, 6 and 12 different proton hyperfine couplings, respectively. By varying the temperature, the ESR spectra of the α- and δ-tocopherol model cations exhibit line-width alternation phenomena characteristic of the hindered rotation of the OH group. However, neither the β- nor the γ-tocopherol model cation radical ESR spectra show any sign of an alternative line-width effect. These results are interpreted by assuming that the β- and γ-tocopherol model cations are stabilized in the trans and cis conformations, respectively. On tocopherol model cations are stabilized in the trans and cis conformations, respectively. On the other hand, both the α- and δ-tocopherol model cations exist as cis and trans isomers. 相似文献
977.
Hiroshi?SakuraEmail author Naotake?Hashimoto Kazuo?Sasamoto Hiroshi?Ohashi Sumiko?Hasumi Noriko?Ujihara Tadasu?Kasahara Osamu?Tomonaga Hideo?Nunome Masashi?Honda Yasuhiko?Iwamoto for the JAMP Study Investigators 《BMC endocrine disorders》2016,16(1):70
Background
To investigate the ameliorating effect of sitagliptin, a dipeptidyl peptidase-4 inhibitor, on blood glucose control in patients with type 2 diabetes mellitus who were previously untreated with or who have a poor responsive to existing antidiabetic drugs.Methods
Sitagliptin (50 mg/day) was added on to the pre-existing therapy for type 2 diabetes and changes in the glycated hemoglobin (HbA1c) level after 3 months of treatment were compared with the baseline and performed exploratory analysis.Results
HbA1c levels were significantly decreased after 1 month of treatment compared to baseline, with a mean change in HbA1c level from baseline of ?0.73% (range, ?0.80 to ?0.67) in the entire study population at 3 months. Patients who received a medium dose of glimepiride showed the least improvement in HbA1c levels. The percentage of patients who achieved an HbA1c level of <7.0% significantly increased after 1 month of treatment, reaching 53.1% at 3 months. The percentage of patients who achieved a fasting blood glucose level of <130 mg/dL significantly increased after 1 month of treatment, reaching 50.9% at 3 months.Conclusions
Sitagliptin improved the HbA1c level and rate of achieving the target control levels in patients with type 2 diabetes mellitus who were previously untreated with, or poorly responsive to, existing antidiabetic drugs. Thus, sitagliptin is expected to be useful in this patient group. However, the additional administration of sitagliptin in patients treated with medium-dose glimepiride only slightly improved blood glucose control when corrected for baseline HbA1c level.978.
Kazutoshi Fujibayashi Toshiaki Gunji Hirohide Yokokawa Toshio Naito Noriko Sasabe Mitsue Okumura Kimiko Iijima Katsuhiko Shibuya Teruhiko Hisaoka Hiroshi Fukuda 《PloS one》2016,11(3)
Background
Most studies on the relationships between metabolic disorders (hypertension, dyslipidemia, and impaired glucose tolerance) and hepatic steatosis (HS) or visceral fat accumulation (VFA) have been cross-sectional, and thus, these relationships remain unclear. We conducted a retrospective cohort study to clarify the relationships between components of metabolic disorders and HS/VFA.Methods
The participants were 615 middle-aged men who were free from serious liver disorders, diabetes, and HS/VFA and underwent multiple general health check-ups at our institution between 2009 and 2013. The data from the initial and final check-ups were used. HS and VFA were assessed by computed tomography. HS was defined as a liver to spleen attenuation ratio of ≤1.0. VFA was defined as a visceral fat cross-sectional area of ≥100 cm2 at the level of the navel. Metabolic disorders were defined using Japan’s metabolic syndrome diagnostic criteria. The participants were divided into four groups based on the presence (+) or absence (-) of HS/VFA. The onset rates of each metabolic disorder were compared among the four groups.Results
Among the participants, 521, 55, 24, and 15 were classified as HS(-)/VFA(-), HS(-)/VFA(+), HS(+)/VFA(-), and HS(+)/VFA(+), respectively, at the end of the study. Impaired glucose tolerance was more common among the participants that exhibited HS or VFA (p = 0.05). On the other hand, dyslipidemia was more common among the participants that displayed VFA (p = 0.01).Conclusions
It is likely that VFA is associated with impaired glucose tolerance and dyslipidemia, while HS might be associated with impaired glucose tolerance. Unfortunately, our study failed to detect associations between HS/VFA and metabolic disorders due to the low number of subjects that exhibited fat accumulation. Although our observational study had major limitations, we consider that it obtained some interesting results. HS and VFA might affect different metabolic disorders. Further large-scale longitudinal studies are needed to reveal the relationships between the components of metabolic disorders and HS/VFA. 相似文献979.
Akio Nakashima Keiko Tanimura-Ito Noriko Oshiro Satoshi Eguchi Takafumi Miyamoto Ayaka Momonami Shinji KamadaKazuyoshi Yonezawa Ushio Kikkawa 《FEBS letters》2013
Target of rapamycin complex 1 (TORC1) has a key role in cellular regulations in response to environmental conditions. In yeast, Tip41 downregulates TORC1 signaling via activation of PP2A phosphatase. We show here that overexpression of TIPRL, a mammalian Tip41, suppressed dephosphorylation of mechanistic TORC1 (mTORC1) substrates under amino acid withdrawal, and knockdown of TIPRL conversely attenuated phosphorylation of those substrates after amino acid refeeding. TIPRL associated with the catalytic subunit of PP2A (PP2Ac), which was required for the TIPRL action on mTORC1 signaling. Collectively, unlike yeast TIP41, TIPRL has a positive effect on mTORC1 signaling through the association with PP2Ac. 相似文献
980.
Ryo Asaoka Shunsuke Nakakura Hitoshi Tabuchi Hiroshi Murata Yoshitaka Nakao Noriko Ihara Ulfah Rimayanti Makoto Aihara Yoshiaki Kiuchi 《PloS one》2015,10(10)
The purpose of the study was to investigate the correlation between Corneal Visualization Scheimpflug Technology (Corvis ST tonometry: CST) parameters and various other ocular parameters, including intraocular pressure (IOP) with Goldmann applanation tonometry. IOP with Goldmann applanation tonometry (IOP-G), central corneal thickness (CCT), axial length (AL), corneal curvature, and CST parameters were measured in 94 eyes of 94 normal subjects. The relationship between ten CST parameters against age, gender, IOP-G, AL, CST-determined CCT and average corneal curvature was investigated using linear modeling. In addition, the relationship between IOP-G versus CST-determined CCT, AL, and other CST parameters was also investigated using linear modeling. Linear modeling showed that the CST measurement ‘A time-1’ is dependent on IOP-G, age, AL, and average corneal curvature; ‘A length-1’ depends on age and average corneal curvature; ‘A velocity-1’ depends on IOP-G and AL; ‘A time-2’ depends on IOP-G, age, and AL; ‘A length-2’ depends on CCT; ‘A velocity-2’ depends on IOP-G, age, AL, CCT, and average corneal curvature; ‘peak distance’ depends on gender; ‘maximum deformation amplitude’ depends on IOP-G, age, and AL. In the optimal model for IOP-G, A time-1, A velocity-1, and highest concavity curvature, but not CCT, were selected as the most important explanatory variables. In conclusion, many CST parameters were not significantly related to CCT, but IOP usually was a significant predictor, suggesting that an adjustment should be made to improve their usefulness for clinical investigations. It was also suggested CST parameters were more influential for IOP-G than CCT and average corneal curvature. 相似文献