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81.
Kaori Fukushima Kaede Takahashi Mirai Kusaka Kaichi Ishimoto Kanako Minami Shiho Otagaki 《Journal of receptor and signal transduction research》2013,33(4):311-315
AbstractFree fatty acid (FFA) receptors belong to a member of G-protein-coupled receptors. GPCR 120 (GPR120) and GPR40 are identified as FFA receptors and activated via the binding of long- and medium-chain FFAs. The aim of this study was to assess the effects of GPR120 and GPR40 on cell motility and growth in breast cancer cells treated with tamoxifen (TAM). MCF-7 cells were continuously treated with TAM for approximately 6?months. The expression level of GPR40 gene was markedly higher in the long-term TAM treated (MCF-TAM) cells than in MCF-7 cells. In cell motility assay, MCF-TAM cells indicated the high cell motile activity, compared with MCF-7 cells. The cell motile activity of MCF-TAM cells was suppressed by a selective GPR40 antagonist, GW1100. To evaluate the effects of GPR40 on cell growth activity under estrogen-free conditions, cells were maintained in serum-free DMEM without phenol red for 2?days. In estrogen-free conditioned medium, the cell growth rate of MCF-TAM cells was significantly higher than that of MCF-7 cells. In addition, treatment of GW1100 reduced the cell growth rate of MCF-TAM cells. These results suggest that the cell motile and growth activities may be positively regulated through the induction of GPR40 by the long-term TAM treatment in MCF-7 cells. 相似文献
82.
Yuriko Saito Ippei Takahashi Kaori Iwane Noriyuki Okubo Miya Nishimura Masashi Matsuzaka Naoko Wada Takashi Miwa Takashi Umeda Shigeyuki Nakaji 《Luminescence》2013,28(4):569-573
We assessed the association of neutrophil function with glycated hemoglobin (HbA1c) levels in a Japanese general population. Participants were 809 males and females who were over 20 years old living in the Iwaki region in Aomori Prefecture located in northern Japan. Lifestyle parameters (smoking, alcohol consumption, and exercise habits), HbA1c and neutrophil function such as reactive oxygen species (ROS) production capability and phagocytic activity (PA) were measured. ROS production capability was measured before and after phagocytic stimulus to obtain basal ROS production and stimulated ROS production. Level of HbA1c had a positive correlation with basal ROS production (p=0.053), a negative correlation with stimulated ROS production (p=0.072) and PA (p=0.059) only in post‐menopausal groups, and not in pre‐menopausal groups. However, there were no correlations between levels of HbA1c and neutrophil functions in male. In conclusion, in the present study, despite the presence of diabetes, chronic hyperglycemia was found to cause an increase in daily basal ROS production of neutrophils, and increased susceptibility to infection caused by reduced neutrophilic reaction in females in their menopause. Therefore, from the oxidative point of view, strict glycemic control is necessary to prevent post‐menopausal females from developing diabetic complications in spite of the presence of diabetes. 相似文献
83.
Farsenyl pyrophosphate synthase is a potential molecular drug target of risedronate in Babesia bovis
Akio Ueno Mohamad Alaa Terkawi Miki Yokoyama Shinuo Cao Gabriel Aboge Mahmoud Aboulaila Yoshifumi Nishikawa Xuenan Xuan Naoaki Yokoyama Ikuo Igarashi 《Parasitology international》2013,62(2):189-192
A cDNA encoding farnesyl pyrophosphate synthase of Babesia bovis (BbFPPS) has been isolated, cloned and characterized as molecular drug target. Sequence analysis revealed that BbFPPS contains an open reading frame of 1011 bp with predicted 336 amino acids and molecular mass of 38 kDa. Antiserum raised in mice against recombinant BbFPPS expressed in Escherichia coli specifically reacted with native protein of B. bovis parasites by Western blot analysis and indirect immunofluorescent test. Enzymatic assay using recombinant BbFPPS revealed that the Km value of the enzyme for isopentenyl pyrophosphate and dimethylallyl pyrophosphate was 2.494 ± 1.536 μM. Risedronate inhibited the activity of BbFPPS yielding IC50 value of 8.4 ± 1.2 nM. Furthermore, the in vitro growth of B. bovis was significantly inhibited in the presence of a micromolar concentration of risedronate (IC50 = 4.02 ± 0.91 μM). No regrowth of B. bovis was observed at 10 μM of risedronate in the subsequent viability test. These results demonstrate that BbFPPS is the molecular target of risedronate, which could inhibit the in vitro growth of B. bovis. 相似文献
84.
Purpose
To assess the time course of optical quality and intraocular scattering in relation to visual acuity after femtosecond lenticule extraction (FLEx) for the correction of myopia.Methods
This study evaluated 36 eyes of 36 patients with spherical equivalents of −4.38±1.53 D [mean ± standard deviation] who underwent FLEx. Before surgery, and 1 week and 1, 3 and 6 months after surgery, we assessed the modulation transfer function (MTF) cutoff frequency, Strehl ratio, objective scattering index (OSI), and OQAS values (OVs), using a double-pass instrument. We also investigated the relationship of the OSI with corrected distance visual acuity (CDVA) preoperatively and postoperatively.Results
The mean changes in MTF cutoff frequency, Strehl ratio, OSI, OV100%, OV20%, and OV9% preoperatively and 6 months postoperatively were −5.51±15.01, −0.03±0.07, 0.35±0.83, −0.17±0.48, −0.14±0.38, and −0.09±0.22, respectively. We found no significant preoperative correlation between the OSI and logMAR CDVA (Spearman rank correlation coefficient r = 0.068, p = 0.69), and modest, but significant correlations 1 week and 1, 3, and 6 months postoperatively (r = 0.572, r = 0.562, r = 0.542, r = 0.540, p<0.001, respectively).Conclusions
FLEx induced a transient decrease in optical quality in association with an increase in intraocular scattering in the early postoperative period, possibly due to mild interface haze formation, but gradually recovered with time. It is suggested that this transient degradation in optical quality related to an increase in the intraocular scattering may result in a slight delay of CDVA recovery in the early postoperative period. 相似文献85.
Amina Sugimoto Shuhei Nomura Masaharu Tsubokura Tomoko Matsumura Kaori Muto Mikiko Sato Stuart Gilmour 《PloS one》2013,8(8)
Background
The Fukushima Daiichi nuclear disaster caused a global panic by a release of harmful radionuclides. In a disaster setting, misusage of contemporary media sources available today can lead to disseminated incorrect information and panic. The study aims to build a scale which examines associations between media and individual anxieties, and to propose effective media usages for future disaster management.Methods
The University of Tokyo collaborated with the Fukushima local government to conduct a radiation-health-seminar for a total of 1560 residents, at 12 different locations in Fukushima. A 13 item questionnaire collected once before and after a radiation-seminar was used on factor analysis to develop sub-scales for multiple regression models, to determine relationships between the sub-scales and media type consumed. A paired t–test was used to examine any changes in sub-scale of pre- and post-seminar scores.Results
Three sub-scales were revealed and were associated with different media types: was with rumors, while concern for the future was positively associated with regional-newspapers and negatively with national-newspapers. Anxiety about social-disruption was associated with radio. The seminar had a significant effect on anxiety reduction for all the three sub-scales.Conclusion
Different media types were associated with various heightened concerns, and that a radiation seminar was helpful to reduce anxieties in the post-disaster setting. By tailoring post-disaster messages via specific media types, i.e., radio, it may be possible to effectively convey important information, as well as to calm fears about particular elements of post-disaster recovery and to combat rumors. 相似文献86.
Gaku Takibuchi Hirotake Imanishi Mami Morimoto Kaori Ishikawa Kazuto Nakada Noriko Toyama-Sorimachi Yoshiaki Kikkawa Keizo Takenaga Jun-Ichi Hayashi 《Mitochondrion》2013,13(6):881-887
To examine whether polymorphic mtDNA mutations that do not induce significant respiration defects regulate phenotypes of tumor cells, we used mouse transmitochondrial tumor cells (cybrids) with nuclear DNA from C57BL/6 (B6) strain and mtDNA from allogenic C3H strain. The results showed that polymorphic mutations of C3H mtDNA in the cybrids induced hypoxia sensitivity, resulting in a delay of tumor formation on their subcutaneous inoculation into B6 mice. Therefore, the effects of polymorphic mutations in normal mtDNA have to be carefully considered, particularly when we apply the gene therapy to the embryos to replace their pathogenic mtDNA by normal mtDNA. 相似文献
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89.
Toko Tanikawa Yasuhiro Hirano Masako Dannoura Keitarou Yamase Kenji Aono Masahiro Ishii Tetsurou Igarashi Hidetoshi Ikeno Yoichi Kanazawa 《Plant and Soil》2013,373(1-2):317-327
Aim
Ground-penetrating radar (GPR) has been applied to detect coarse tree roots. The horizontal angle of a root crossing a scanning line is a factor that affects both root detection and waveform parameter values. The purpose of this study was to quantitatively evaluate the influence of root orientation (x, degree) on two major waveform parameters, amplitude area (A, dB × ns) and time interval between zero crossings (T, ns).Methods
We scanned four diameter classes of dowels in a sandy bed as simulated roots using a 900 MHz antenna from multiple angles to clarify the relationships between the parameters and x.Results
Angle x strongly affected reflection images and A values. The variation in A(x) fitted a sinusoidal waveform, whereas T was independent of x. The value of A scanning at 90° was estimated by A values of arbitrary x in two orthogonal transects. The sum of T in all reflected waveforms showed a significant linear correlation with dowel diameter.Conclusions
We clarified that root orientation dramatically affected root detection and A values. The sum of T of all reflected waveforms was a suitable parameter for estimating root diameter. Applying grid transects can overcome the effects of root orientation. 相似文献90.
Kaori Yoneyama Xiaonan Xie Takaya Kisugi Takahito Nomura Koichi Yoneyama 《Planta》2013,238(5):885-894
Strigolactones (SLs) are essential host recognition signals for both root parasitic plants and arbuscular mycorrhizal fungi, and SLs or their metabolites function as a novel class of plant hormones regulating shoot and root architecture. Our previous study indicated that nitrogen (N) deficiency as well as phosphorus (P) deficiency in sorghum enhanced root content and exudation of 5-deoxystrigol, one of the major SLs produced by sorghum. In the present study, we examined how N and P fertilization affects SL production and exudation in sorghum plants subjected to short- (5 days) or long-term (10 days) N or P deficiency and demonstrated their common and distinct features. The root contents and exudation of SLs in the N- or P-deficient sorghum plants grown for 6, 12 or 24 h with or without N or P fertilization were quantified by LC–MS/MS. In general, without fertilization, root contents and exudation of SLs stayed at similar levels at 6 and 12 h and then significantly increased at 24 h. The production of SLs responded more quickly to P fertilization than the secretion of SLs, while regulation of SL secretion began earlier after N fertilization. It is suggested that sorghum plants regulate SL production and exudation when they are subjected to nutrient deficiencies depending on the type of nutrient and degree of deficiency. 相似文献