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1.
Pregnancy by Assisted Reproductive Technology Is Associated with Shorter Telomere Length in Neonates
Toshiko Minamoto Kentaro Nakayama Tomoka Ishibashi Masako Ishikawa Kohei Nakamura Hitomi Yamashita Kamrunnahar Shanta Hossain Mohammad Mahmud Sultana Razia Kouji Iida Gyosuke Sakashita Tsukasa Nakamura Hideyuki Kanda Satoru Kyo 《International journal of molecular sciences》2020,21(24)
Telomere length (TL) influences the development of lifestyle-related diseases, and neonatal TL may influence their prevalence. Various factors have been reported to affect neonatal TL. Although the fetus is exposed to multiple conditions in utero, the main factors affecting the shortening of neonatal TL are still not known. In this study, we sought to identify factors that influence fetal TL. A total of 578 mother-newborn pairs were included for TL analysis. TL was measured in genomic DNA extracted from cord blood samples using quantitative PCR. The clinical factors examined at enrollment included the following intrauterine environmental factors: maternal age, assisted reproductive technology (ART) used, body mass index (BMI), gestational diabetes mellitus (GDM), maternal stress, smoking, alcohol consumption, preterm delivery, small-for-gestational-age, neonatal sex, and placental weight. Univariate and multivariate regression analyses were used to verify the relationship between neonatal TL and these clinical factors. The median neonatal TL to single-copy gene ratio was 1.0. Pregnancy with ART was among the 11 factors associated with shorter neonatal TL. From multiple regression analysis, we determined that neonatal TL was significantly shorter for pregnancies in the ART group than in the other groups. We conclude that pregnancy with ART is associated with shorter neonatal TL. 相似文献
2.
Yasuha Watanabe Prof. Kenzo Fujimoto 《Chembiochem : a European journal of chemical biology》2020,21(22):3244-3248
The regulation of DNAzyme activity is an important problem for its in vivo applications. We achieved photochemical regulation of DNAzyme activity by using reversible DNA photo-crosslinking of 3-cyanovinylcarbazole (CNVK). The ODN containing CNVK photo-crosslinked to a pyrimidine base in the complementary strand after a few seconds of photoirradiation, and its photoadduct was split by photoirradiation of another wavelength. The activity of photo-crosslinked DNAzyme with CNVK was completely inhibited (OFF state). In contrast, after 312 nm irradiation, DNAzyme activity was recovered upon addition of a substrate strand (ON state). In addition, the photo-crosslinked DNAzyme is prone to enzymatic digestion by exonuclease. This photochemical OFF to ON switching with reversible DNA photo-crosslinking was regulated at the desired time and position; therefore, it might be possible to use it for in vivo application. 相似文献
3.
Goro Aoyama Kiyoshi Fujimoto Kenichi Katono Takuji Nagayoshi Atsushi Baba Kenichi Yasuda 《Journal of Nuclear Science and Technology》2016,53(4):537-545
A prototype ultrasonic liquid film sensor was applied to a high-temperature steam–water two-phase flow experiment. The liquid film sensor was vertically installed in a loop which was connected to HUSTLE, a multi-purpose steam source test facility. The hydraulic diameter of the measurement section was 9.4 mm. The output waveforms of the sensor were acquired with a digital oscilloscope. The fluid temperature and system pressure were kept at 288 °C and 7.2 MPa, respectively, during the experiment. The pulse-echo method was used to calculate the liquid film thickness. The cross-correlation calculation was utilized to determine the time difference between the pulse reflected at the sensor surface and the pulse reflected at the liquid film surface. The time-averaged liquid film thicknesses were less than 0.055 mm in the annular flow condition. The increase of the time-averaged thickness was small with the change of the gas momentum flux. The film thicknesses measured with the sensor were compared with the past experimental results; the former were smaller than one-fourth of the thickness estimated as the mean film thickness. The comparison results suggested that the continuous liquid sublayer thickness was measured with the liquid film sensor. 相似文献
4.
F. Yuasa E. de Doncker N. Hamaguchi T. Ishikawa K. Kato Y. Kurihara J. Fujimoto Y. Shimizu 《Computer Physics Communications》2012,183(10):2136-2144
A new approach is presented to evaluate multi-loop integrals, which appear in the calculation of cross-sections in high-energy physics. It relies on a fully numerical method and is applicable to a wide class of integrals with various mass configurations. As an example, the computation of two-loop planar and non-planar box diagrams is shown. The results are confirmed by comparisons with other techniques, including the reduction method, and by a consistency check using the dispersion relation. 相似文献
5.
Issei Fujimoto Nini Wang Rie Saito Yugo Miseki Takahiro Gunji Kazuhiro Sayama 《International Journal of Hydrogen Energy》2014
We report on the improvement in the water splitting efficiency of a WO3/BiVO4 composite photoelectrode by the application of an improved auto-combustion method to the preparation of porous BiVO4 thin films. The unique feature of this preparation method is the addition of both NH4NO3, as a strong oxidizing agent, and an organic additive into BiVO4 precursor solution. The local decomposition heat of the organic additive and oxidizing agent created a porous film with small, highly crystalline BiVO4 particles. The photoelectrode has many advantages over existing ones, such as the high light-harvesting efficiency (LHE), a single BiVO4 phase, the facile access of the holes to the photoelectrode/electrolyte interface, and the ease of water and oxygen diffusion. The maximum incident photon-to-current efficiency (IPCE) was estimated to be 64% (at 440 nm, 1.23 V vs. RHE) and the applied bias photon-tocurrent efficiency (ABPE) reached as high as 1.28%. This ABPE value is highest among all oxide semiconductor photoelectrodes reported previously, except for the case of a stacking photoelectrode system. 相似文献
6.
Herein we propose a production scheme for conductive films composed of thin graphite sheets with high crystallinity and polymeric resin. The crystalline graphite sheets were successfully produced from natural graphite powder by solution-phase synthesis of graphite intercalation compounds (GICs), following a wet planetary-ball milling under mild conditions. The shear forces in the milling pot lead to a peeling of graphite flakes. Taking into consideration the interlayer bonding force, the delamination should be preferentially done from the expanded GICs interlayer rather than intrinsic graphite one. Some composite films derived from the phenolic resin and flaky graphite sheets displayed much higher electrical conductivities compared to the film from the feed graphite particles. We also demonstrate the stage structure of synthetic GICs affected the film conductivity. The composite films made from exfoliated products of ground (around stage IV) GICs exhibited high electrical conductivity with a small amount of the graphite sheets. 相似文献
7.
8.
T. Kato H. Funahashi H. Nakamura M. Fujimoto T. Machida H. Sakata S. Nakao T. Hasegawa 《Journal of Superconductivity and Novel Magnetism》2010,23(5):771-773
We have performed low-temperature scanning tunneling spectroscopy on overdoped Bi2Sr2−x
La
x
CuO6+δ
(x=0.1 and 0.2) at 4.2 K. The tunneling spectra in both samples obviously exhibit two energy gaps: one has clear gap structure
with sharp gap edge peaks, and another is observed as kinks inside the larger gap. Both the energy gaps inhomogeneously vary
on the surface at nanometer scale, and their values positively correlate each other. The distributions of both gaps normalized
to the mean values are identical independent of the doping level. These results suggest that the two gaps are commonly affected
by the source of the electronic disorder. 相似文献
9.
The objective of this study was to improve bending strength properties of three-layer wood–porcelain stone composite board. The focus of this study was on the effects of orientations and weight ratios of bamboo fiber in face layer on physical and mechanical properties of the board. Three types of board with different orientation of bamboo fibers in the face layer were manufactured: one in which the fibers were oriented at random orientation (R board), another in which the fibers were oriented at unidirectional orientation (U board), and a third in which the fibers were oriented at cross orientation (C board). The physical and mechanical properties of the boards were evaluated based on the Japanese Industrial Standard for Particleboards. The main results obtained were as follows: Bending strength properties of the board were strongly affected by both orientation and weight ratio of bamboo fibers. Perpendicular specimen of C board has larger bending strength properties than U board and the value become larger with increased weight ratio of bamboo fibers. Internal bond strength value decreased with increasing weight ratio of bamboo fibers. The effect of orientation and weight ratios of bamboo fiber on thickness swelling of the board was not significant. 相似文献
10.
Scintillation properties of Tm-doped Lu3Al5O12 single crystals 总被引:1,自引:0,他引:1
Makoto Sugiyama Yutaka Fujimoto Takayuki Yanagida Daisuke Totsuka Yuui Yokota Akira Yoshikawa 《Optical Materials》2011,34(2):439-443
Using the micro-pulling-down (μ-PD) method, Tm-doped Lu3Al5O12 (Tm:LuAG) single crystals were grown to examine their scintillation properties. In transmittance spectra, they exhibited about 80% transparency in the wavelengths longer than 320 nm and five absorption lines due to Tm3+ 4f–4f transitions were observed. 241Am α-ray excited radioluminescence spectra were measured and intense 4f–4f emission peaks were observed with the host emission. When excited by 137Cs γ-Ray to obtain pulse height spectra, Tm 1% doped LuAG showed the highest light yield coupled with a photomultiplier (PMT) or a silicon avalanche photodiode (Si-APD). The light yield was estimated to be 5800 and 7300 photons/MeV for PMT and Si-APD, respectively. Decay time profiles consist of two exponential components and the fast and slow components are considered to be attributed to the host and the combination of the host and Tm3+ 4f–4f emission, respectively. 相似文献