42 results on '"Asato K"'
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2. Combined effects of vortex flow and the Shchelkin spiral dimensions on characteristics of deflagration-to-detonation transition
- Author
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Asato, K., Miyasaka, T., Watanabe, Y., and Tanabashi, K.
- Published
- 2013
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3. Chromosomal-level assembly of Tokudaia osimensis, Tokudaia tokunoshimensis, and Tokudaia muenninki genomes
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Miki Okuno, Yuta Mochimaru, Kentaro Matsuoka, Takahiro Yamabe, Luisa Matiz-Ceron, Takamichi Jogahara, Atsushi Toyoda, Asato Kuroiwa, and Takehiko Itoh
- Subjects
Science - Abstract
Abstract Herein, we present the first high-quality long-read-based chromosome-level genome assemblies and gene annotations of the genomes of three endangered Tokudaia species: Tokudaia osimensis, Tokudaia tokunoshimensis, and Tokudaia muenninki. These species, which are endemic to different islands of the Ryukyu Islands, Japan, exhibited unique karyotypes and sex chromosomal characteristics. The genome assemblies generated using PacBio, Illumina, and Hi-C sequence data consisted of 13 (corresponded to 12 autosomes and one X chromosome), 23 (corresponded to 22 autosomes and one X chromosome), and 23 (corresponded to 21 autosomes and the neo- and ancestral X regions) chromosome-level scaffolds that contained 2,445, 2,477, and 2,661 Mbp of sequence data, respectively. Annotations of protein-coding genes were performed using RNA-Seq-based, homology-based, and Ab initio methods. BUSCO completeness values for every species exceeded 96% for genomes and 98% for genes. These data can be an important resource for contributing to our understanding of species genomes resulting from allopatric speciation and provide insights into mammalian sex-determination mechanisms and sex chromosome evolution.
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- 2023
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4. Research Note: Diethylstilbestrol reduces primordial germ cells in male Japanese quail
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Shusei Mizushima and Asato Kuroiwa
- Subjects
DEAD-box polypeptide 4 ,diethylstilbestrol ,Japanese quail ,primordial germ cell ,proliferating cell nuclear antigen ,Animal culture ,SF1-1100 - Abstract
ABSTRACT: This study investigated the detrimental effects of diethylstilbestrol (DES), an estrogenic endocrine-disrupting chemical, on the viability of primordial germ cells (PGCs), embryonic precursors of germ cells, in Japanese quail. We injected 50 or 100 nmol DES solubilized in sesame oil into the yolk of stage X embryos and assessed changes in the population and cell cycle properties of circulating PGCs in blood vessels and gonadal PGCs after 2.5- and 7-day incubations, respectively. Liquid chromatography tandem mass spectrometer and Western blotting analyses identified DEAD-box polypeptide 4 (DDX4) and proliferating cell nuclear antigen (PCNA) as a stem cell marker and proliferation marker of quail PGCs, respectively. Immunochemical analyses revealed significant decreases in the number of DDX4- and PCNA-positive blood-circulating PGCs in males treated with 50 and 100 nmol DES than in the oil-treated control group. These reductions were not observed in females. Furthermore, the number of DDX4-positive gonadal PGCs was smaller in males treated with 50 and 100 nmol DES than in the control group, and these reductions were not observed in females. The protein expression of the Sertoli cell marker showed normal testis development in DES-treated embryos on d 7. These results demonstrate the potentially cytotoxic effects of DES on male germ cells, namely, the inhibition of cell cycle progression and induction of apoptosis in Japanese quail.
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- 2023
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5. Inositol-1,4,5-Trisphosphate Receptor-1 and -3 and Ryanodine Receptor-3 May Increase Ooplasmic Ca2+ During Quail Egg Activation
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Shusei Mizushima, Tomohiro Sasanami, Tamao Ono, Norio Kansaku, and Asato Kuroiwa
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egg activation ,inositol 1,4,5-trisphosphate receptor ,intracellular ca2+ ,japanese quail ,ryanodine receptor ,Animal culture ,SF1-1100 - Abstract
We previously reported that egg activation in Japanese quail is driven by two distinct types of intracellular Ca2+ ([Ca2+]i): transient elevations in [Ca2+]i induced by phospholipase Czeta 1 (PLCZ1) and long-lasting spiral-like Ca2+ oscillations by citrate synthase (CS) and aconitate hydratase 2 (ACO2). Although the blockade of inositol 1,4,5-trisphosphate receptors (ITPRs) before microinjections of PLCZ1, CS, and ACO2 cRNAs only prevented transient increases in [Ca2+]i, a microinjection of an agonist of ryanodine receptors (RYRs) induced spiral-like Ca2+ oscillations, indicating the involvement of both ITPRs and RYRs in these events. In this study, we investigated the isoforms of ITPRs and RYRs responsible for the expression of the two types of [Ca2+]i increases. RT-PCR and western blot analyses revealed that ITPR1, ITPR3, and RYR3 were expressed in ovulated eggs. These proteins were degraded 3 h after the microinjection of PLCZ1, CS, and ACO2 cRNAs, which is the time at which egg activation was complete. However, degradation of ITPR1 and ITPR3, but not RYR3, was initiated 30 min after a single injection of PLCZ1 cRNA, corresponding to the time of the initial Ca2+ wave termination. In contrast, RYR3 degradation was observed 3 h after the microinjection of CS and ACO2 cRNAs. These results indicate that ITPRs and RYR3 differentially mediate increases in [Ca2+]i during egg activation in Japanese quail, and that downregulation of ITPRs and RYR3-mediated events terminate the initial Ca2+ wave and spiral-like Ca2+ oscillations, respectively.
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- 2022
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6. Stability and performacne analysis of passive and active stall control of small-scaled wind turbine system by phase plane method
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Asharif, F., primary, Futami, M., additional, Tamaki, S., additional, Nagado, T., additional, and Asato, K., additional
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- 2015
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7. A surgical navigation system for aortic vascular surgery: A practical approach
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Uematsu, M., primary, Asato, K., additional, Ichihashi, T., additional, Umezu, M., additional, Nakaoka, R., additional, Matsuoka, A., additional, Aomi, S., additional, Iimura, H., additional, Suzuki, T., additional, Muragaki, Y., additional, and Iseki, H., additional
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- 2013
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8. Metastatic placental site trophoblastic tumour successfully treated with hysterectomy and EMA/CO chemotherapy
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Nagai, Y., primary, Wakayama, A., additional, Suzuki, S., additional, Asato, K., additional, Hirakawa, M., additional, Kudaka, W., additional, Inamine, M., additional, and Aoki, Y., additional
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- 2011
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9. Controller reduction using structurally balanced truncation method with new closed-loop structures
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Asato, K., primary, Nagado, T., additional, and Tamaki, S., additional
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- 2007
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10. Sexual dimorphism in brain transcriptomes of Amami spiny rats (Tokudaia osimensis): a rodent species where males lack the Y chromosome
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Madison T. Ortega, Nathan J. Bivens, Takamichi Jogahara, Asato Kuroiwa, Scott A. Givan, and Cheryl S. Rosenfeld
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Sexual differentiation ,Organizational-Activational programming ,Rodent ,Endangered animals ,SRY ,Steroid hormones ,Biotechnology ,TP248.13-248.65 ,Genetics ,QH426-470 - Abstract
Abstract Background Brain sexual differentiation is sculpted by precise coordination of steroid hormones during development. Programming of several brain regions in males depends upon aromatase conversion of testosterone to estrogen. However, it is not clear the direct contribution that Y chromosome associated genes, especially sex-determining region Y (Sry), might exert on brain sexual differentiation in therian mammals. Two species of spiny rats: Amami spiny rat (Tokudaia osimensis) and Tokunoshima spiny rat (T. tokunoshimensis) lack a Y chromosome/Sry, and these individuals possess an XO chromosome system in both sexes. Both Tokudaia species are highly endangered. To assess the neural transcriptome profile in male and female Amami spiny rats, RNA was isolated from brain samples of adult male and female spiny rats that had died accidentally and used for RNAseq analyses. Results RNAseq analyses confirmed that several genes and individual transcripts were differentially expressed between males and females. In males, seminal vesicle secretory protein 5 (Svs5) and cytochrome P450 1B1 (Cyp1b1) genes were significantly elevated compared to females, whereas serine (or cysteine) peptidase inhibitor, clade A, member 3 N (Serpina3n) was upregulated in females. Many individual transcripts elevated in males included those encoding for zinc finger proteins, e.g. zinc finger protein X-linked (Zfx). Conclusions This method successfully identified several genes and transcripts that showed expression differences in the brain of adult male and female Amami spiny rat. The functional significance of these findings, especially differential expression of transcripts encoding zinc finger proteins, in this unusual rodent species remains to be determined.
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- 2019
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11. Isolation and Characterization by <SUP>13</SUP>C NMR Spectroscopy of [84]Fullerene Minor Isomers
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Dennis, T. J. S., Kai, T., Asato, K., Tomiyama, T., Shinohara, H., Ishiwatari, H., Miyake, Y., Kikuchi, K., Achiba, Y., Yoshida, T., and Kobayashi, Y.
- Abstract
The isolation of minor isomers of [84]fullerene (C
84 ), five in total, and their characterization by 13C NMR spectroscopy, have been reported for the first time. The vis−near-infrared absorption spectra for these isomers are also reported. The 13C NMR results indicate that the isolated C84 isomers have, in order of decreasing abundance, C2 , Cs (a), C s (b), D2 d (I), and D 2 (II) molecular point group symmetry. In addition, we have found another C84 minor isomer adjacent to Cs (b)-C84 in the HPLC chromatogram.- Published
- 1999
12. Characteristics of Flame Propagation in a Vortex Core: Validity of a Model for Flame Propagation
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Asato, K., Wada, H., Hiruma, T., and Takeuchi, Y.
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- 1997
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13. Explanation of the blowoff of inverted flames by the area-increase concept
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KAWAMURA, T, primary, ASATO, K, additional, MAZAKI, T, additional, HAMAGUCHI, T, additional, and KAYAHARA, H, additional
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- 1979
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14. A 2-D adaptive joint-process IIR filter with generalized lattice structure
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Yamashita, K., primary, Kinjyo, T., additional, Asato, K., additional, and Miyagi, H., additional
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15. Next day load curve forecasting using hybrid correction method
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Senjyu, T., primary, Takara, H., additional, Asato, K., additional, Uezato, K., additional, and Funabashi, T.F., additional
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16. Mutations in the testis-specific enhancer of SOX9 in the SRY independent sex-determining mechanism in the genus Tokudaia.
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Ryutaro Kimura, Chie Murata, Yoko Kuroki, and Asato Kuroiwa
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Medicine ,Science - Abstract
SRY (sex-determining region Y) is widely conserved in eutherian mammals as a sex-determining gene located on the Y chromosome. SRY proteins bind to the testis-specific enhancer of SOX9 (TES) with SF1 to upregulate SOX9 expression in undifferentiated gonads of XY embryos of humans and mice. The core region within TES, named TESCO, is an important enhancer for mammalian sex determination. We show that TESCO of the genus Tokudaia lost enhancer activity caused by mutations in its SRY and SF1 binding sites. Two species of Tokudaia do not have the Y chromosome or SRY, and one species has multiple SRYs located on the neo-Y chromosome consisting of the Y fused with an autosome. The sequence of Tokudaia TESCO exhibited more than 83% identity with mouse TESCO, however, nucleotide substitution(s) were found in two out of three SRY binding sites and in five out of six SF1 binding sites. TESCO of all species showed low enhancer activity in cells co-transfected with SRY and SF1, and SOX9 and SF1 in reporter gene assays. Mutated TESCO, in which nucleotide substitutions found in SRY and SF1 binding sites were replaced with mouse sequence, recovered the activity. Furthermore, SRYs of the SRY-positive species could not activate the mutated TESCO or mouse TESCO, suggesting that SRYs lost function as a sex-determining gene any more. Our results indicate that the SRY dependent sex-determining mechanism was lost in a common ancestor of the genus Tokudaia caused by nucleotide substitutions in SRY and SF1 binding sites after emergence of a new sex-determining gene. We present the first evidence for an intermediate stage of the switchover from SRY to a new sex-determining gene in the evolution of mammalian sex-determining mechanism.
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- 2014
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17. B chromosomes have a functional effect on female sex determination in Lake Victoria cichlid fishes.
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Kohta Yoshida, Yohey Terai, Shinji Mizoiri, Mitsuto Aibara, Hidenori Nishihara, Masakatsu Watanabe, Asato Kuroiwa, Hirohisa Hirai, Yuriko Hirai, Yoichi Matsuda, and Norihiro Okada
- Subjects
Genetics ,QH426-470 - Abstract
The endemic cichlid fishes in Lake Victoria are a model system for speciation through adaptive radiation. Although the evolution of the sex-determination system may also play a role in speciation, little is known about the sex-determination system of Lake Victoria cichlids. To understand the evolution of the sex-determination system in these fish, we performed cytogenetic analysis in 11 cichlid species from Lake Victoria. B chromosomes, which are present in addition to standard chromosomes, were found at a high prevalence rate (85%) in these cichlids. In one species, B chromosomes were female-specific. Cross-breeding using females with and without the B chromosomes demonstrated that the presence of the B chromosomes leads to a female-biased sex ratio in this species. Although B chromosomes were believed to be selfish genetic elements with little effect on phenotype and to lack protein-coding genes, the present study provides evidence that B chromosomes have a functional effect on female sex determination. FISH analysis using a BAC clone containing B chromosome DNA suggested that the B chromosomes are derived from sex chromosomes. Determination of the nucleotide sequences of this clone (104.5 kb) revealed the presence of several protein-coding genes in the B chromosome, suggesting that B chromosomes have the potential to contain functional genes. Because some sex chromosomes in amphibians and arthropods are thought to be derived from B chromosomes, the B chromosomes in Lake Victoria cichlids may represent an evolutionary transition toward the generation of sex chromosomes.
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- 2011
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18. Next day load curve forecasting using hybrid correction method.
- Author
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Senjyu, T., Takara, H., Asato, K., Uezato, K., and Funabashi, T.F.
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- 2002
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19. A 2-D adaptive joint-process IIR filter with generalized lattice structure.
- Author
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Yamashita, K., Kinjyo, T., Asato, K., and Miyagi, H.
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- 1998
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20. Signaling through the interleukin-18 receptor α attenuates inflammation in cisplatin-induced acute kidney injury.
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Nozaki Y, Kinoshita K, Yano T, Asato K, Shiga T, Hino S, Niki K, Nagare Y, Kishimoto K, Shimazu H, Funauchi M, Matsumura I, Nozaki, Yuji, Kinoshita, Koji, Yano, Tomohiro, Asato, Kayo, Shiga, Toshihiko, Hino, Shoichi, Niki, Kaoru, and Nagare, Yasuaki
- Abstract
Interleukin (IL)-18 is produced by leukocytes and renal parenchymal cells (tubular epithelial cells, podocytes, and mesangial cells). The IL-18 receptor (IL-18R) is expressed on these cells in cisplatin-induced acute kidney injury, but the role of IL-18R is unknown. To help define this, we compared IL-18Rα knockout with wild-type mice in cisplatin-induced acute kidney injury and found deteriorated kidney function, tubular damage, increased accumulation of leukocytes (CD4(+) and CD8(+) T-cells, macrophages, and neutrophils), upregulation of early kidney injury biomarkers (serum TNF, urinary IL-18, and KIM-1 levels), and increased expression of pro-inflammatory molecules downstream of IL-18. In vitro, leukocytes from the spleen and kidneys of the knockout mice produced greater amounts of pro-inflammatory cytokines upon stimulation with concanavalin A compared to that in wild-type mice. Levels of the suppressor of cytokine signaling 1 and 3 (negative regulators of cytokine signaling) were reduced in the spleen and kidneys of IL-18Rα-deficient compared to wild-type mice. Adoptive transfer of wild-type splenocytes by IL-18Rα-deficient mice led to decreased cisplatin nephrotoxicity compared to control IL-18Rα-deficient mice. In contrast, anti-IL-18Rα and anti-IL-18Rβ antibody treatment tended to increase cisplatin nephrotoxicity in wild-type mice. Thus, signaling through IL-18Rα activates both inflammation-suppressing and pro-injury pathways in cisplatin-induced acute kidney injury. [ABSTRACT FROM AUTHOR]
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- 2012
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21. Dietary intake of methylmercury by 0-5 years children using the duplicate diet method in Japan.
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Tatsuta N, Asato K, Iwai-Shimada M, Iwai K, Nakayama SF, Yamazaki S, and Nakai K
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- Humans, Infant, Child, Preschool, Japan, Female, Male, Dietary Exposure analysis, Diet statistics & numerical data, Infant, Newborn, Environmental Pollutants analysis, Mercury analysis, Infant Food analysis, Methylmercury Compounds analysis, Hair chemistry, Food Contamination analysis
- Abstract
Background: The developing brains are sensitive to methylmercury (MeHg). However, the exposure to MeHg in baby foods and toddler meals remains unknown. This study aimed to determine MeHg intake from baby food or toddler meals, and to investigate the relationship with child hair total mercury (THg)., Methods: A total of 3 days of 24-hour dietary diet and hair samples were collected from 260 consenting children aged 0-5 years. We measured the concentrations of THg and MeHg in the diet and THg in the hair., Results: The results of measuring THg were below both the method detection and method quantification limits or either of both in powdered milk (93.8%), 5-6 months (53.3%), and 7-8 months (39.5%). The median daily THg intake was 20.3 (95% confidence interval 0.72-232.5) ng/kgbw. MeHg was not detected in 213 samples with dietary THg concentrations below 1 ng/g. The MeHg concentration with THg concentrations of 1 ng/g or higher was 1.70 (0.87-6.21) ng/g, and MeHg percentage in THg was 90.0%. To estimate MeHg intake, we multiplied the THg concentration by 90.0%, resulting in an estimated MeHg intake of 18.3 (0.65-209.2) ng/kgbw/day. The THg in children's hair was 1.05 (0.31-3.96) ppm, and a weak positive correlation was observed between hair THg and dietary MeHg (r = 0.170)., Conclusions: This study highlights the accurate estimation of MeHg intake in children using a duplicate method. Japanese children consume fish, the MeHg intakes exceeded the reference dose and/or provisional tolerable weekly intake in several children. Further discussion based on epidemiological data is required.
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- 2024
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22. Factors associated with postpartum smoking relapse at early postpartum period of Japanese women in the Japan Environmental and Children's Study.
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Anai A, Asato K, Tatsuta N, Sakurai K, Ota C, Kuriyama S, Sugawara J, Arima T, Yaegashi N, and Nakai K
- Abstract
Background: Postpartum smoking relapse is a serious public health concern. Previous studies have identified several risk factors for postpartum smoking relapse; however, very little is known about the predictors of early postpartum smoking relapse. This study aimed to determine postpartum smoking relapse status and its associated risk factors at 1 month postpartum among Japanese women., Methods: Data were obtained from 93,851 mothers with live births in an ongoing birth cohort study, the Japan Environment and Children's Study. Data on smoking status and confounding variables were collected using self-administered questionnaires and medical record transcripts. Self-administered questionnaires were administered during the first trimester, second/third trimester, and 1 month after delivery. A multiple logistic regression analysis was performed., Results: Among the 14,326 mothers who smoked during pregnancy, 10,917 (76.2%) quit smoking during pregnancy. Subsequently, 617 (5.7%) of the mothers who had quit relapsed smoking at 1 month postpartum. Maternal age (≤24, ≥35), maternal education (≤12 years), parity (≥Second), feeding method (Formula milk), partner smoking status during pregnancy (Smoker), number of cigarettes per day before the cessation of smoking (≥11), maternal alcohol consumption at 1-month postpartum (Drinker), postpartum depression (EPDS score ≥9), and spending time at the parents' home after delivery (≥14 days) were associated with smoking relapse., Conclusions: A certain number of mothers relapsed even 1 month postpartum. Besides mother's alcohol and smoking habit before pregnancy, breastfeeding and partner smoking are important factors in early postpartum smoking relapse in Japan.
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- 2023
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23. Timing of Maternal Smoking Cessation and Newborn Weight, Height, and Head Circumference.
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Tatsuta N, Asato K, Anai A, Suzuki T, Sakurai K, Ota C, Arima T, Sugawara J, Yaegashi N, and Nakai K
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- Pregnancy, Child, Infant, Newborn, Humans, Male, Female, Smoking adverse effects, Birth Weight, Cohort Studies, Pregnancy Trimester, First, Smoking Cessation
- Abstract
Objective: To examine the relationship between timing of smoking cessation during pregnancy and anthropometric indices of newborns., Methods: Mothers and neonates enrolled in the JECS (Japan Environment and Children's Study), a nationwide birth cohort study, were examined. Patients with full-term neonates were included in the analysis, and 73,025 mother-neonate pairs with complete data were identified. The mothers were classified into six groups according to smoking status during pregnancy (nonsmokers [Q1, n=44,198]; ex-smokers who quit before pregnancy [Q2, n=16,461]; ex-smokers who quit in the first trimester [Q3, n=8,948]; ex-smokers who quit in the second trimester [Q4, n=498]; ex-smokers who quit in the third trimester [Q5, n=651]; and smokers who smoked throughout pregnancy [Q6, n=2,269)]). Data on smoking were based on questionnaires administered in the first, second, or third trimester and 1 month after delivery. The primary outcomes were birth weight, height, and head circumference., Results: Compared with nonsmokers (Q1), no adverse outcomes were observed for ex-smokers who quit before pregnancy (Q2). The mean adjusted weights of male and female neonates were 135 g and 125 g lower, respectively, in Q6 participants than in Q1 participants. Comparing Q1 and Q6 participants, height was 0.6 cm and 0.7 cm smaller for male and female neonates, respectively. Head circumference in neonates of Q6 participants was 0.3 cm and 0.3 cm smaller for male and female neonates, respectively, than that in Q1 participants. Across all three measures, smoking cessation in the first and second trimester reduced the differential in outcomes between nonsmokers and individuals who smoked throughout pregnancy., Conclusion: Smoking during pregnancy is associated with reduced newborn birth weight, height, and head circumference. Earlier smoking cessation during pregnancy reduces the adverse effects of smoking on fetal growth., Competing Interests: Financial Disclosure The authors did not report any potential conflicts of interest., (Copyright © 2022 The Author(s). Published by Wolters Kluwer Health, Inc.)
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- 2023
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24. Association between whole blood metallic elements concentrations and gestational diabetes mellitus in Japanese women: The Japan environment and Children's study.
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Tatsuta N, Iwai-Shimada M, Nakayama SF, Iwama N, Metoki H, Arima T, Sakurai K, Anai A, Asato K, Kuriyama S, Sugawara J, Suzuki K, Yaegashi N, Kamijima M, and Nakai K
- Subjects
- Cohort Studies, Female, Humans, Japan epidemiology, Maternal Exposure adverse effects, Pregnancy, Diabetes, Gestational chemically induced, Diabetes, Gestational epidemiology, Mercury
- Abstract
Background: Exposure to several metallic elements has been suggested as a risk factor for gestational diabetes mellitus (GDM), but inconsistent findings have been reported. This study aimed to examine the association between the maternal whole blood concentration of metallic elements (Hg, Pb, Cd, Mn, and Se) and GDM using the dataset of the Japan Environment and Children's Study (JECS), a nationwide birth cohort study, which was designed to examine the adverse effects of pre/post-natal exposure to hazardous environment., Methods: The data of 78,964 pregnant women who were participants of JECS were used. Blood samples were collected from the pregnant women at second/third trimester of gestation. We employed logistic regression analysis, quantile g-computation (QGC) and a distributed lag nonlinear model (DLNM) to examine the association between the blood concentration of metallic elements and the risk of GDM., Results: The prevalence of GDM was 2.1%. In the logistic regression analyses, maternal blood Hg was associated with an increased risk of GDM. In QGC analysis, although metallic elements mixtures were not related to an increased risk of GDM, Hg (52.6%) may be the main contributor. According to the results of DLNM, for maternal exposure to Hg, 4.99 ng/g was identified as its susceptible minimum window for elevated risk of GDM., Conclusions: Our findings highlighted an association between Hg exposure and an increased risk of GDM. Studies of the underlying mechanisms and potential contributing factors, including fish intake, of this association are warranted., (Copyright © 2022 The Authors. Published by Elsevier Inc. All rights reserved.)
- Published
- 2022
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25. Case study of the convergent evolution in the color patterns in the freshwater bivalves.
- Author
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Asato K, Nakayama K, and Imai T
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- Animals, Fossils, Fresh Water, Phylogeny, Bivalvia, Ecosystem
- Abstract
The class Bivalvia (phylum Mollusca) is one of the most successful at survival groups of animals with diverse color patterns on their shells, and they are occasionally preserved in the fossil record as residual color patterns. However, the fossil record of the residual color patterns in freshwater bivalves could be traced only to the Miocene, greatly limiting color pattern evolution knowledge. We present the color patterns of the Cretaceous freshwater bivalves belonging to three extinct families of the order Trigoniida (hereinafter the Kitadani Freshwater Bivalves) from Japan, which is the oldest and the second fossil record of freshwater molluscan color patterns. The Kitadani Freshwater Bivalves consists of two types of color patterns: stripes along the growth lines and radial rays tapered toward the umbo, which resemble that of the colored bands of extant freshwater bivalves. This resemblance of the color patterns between the Kitadani Freshwater Bivalves and the extant species indicates that the color patterns of the freshwater bivalves represent the convergent evolution between Trigoniida and Unionida. To explain this convergent evolution, we advocate three conceivable factors: the phylogenetic constraints, monotonous habitats typical of freshwater ecosystems, and the predation pressure by visual predators in freshwater sediments., (© 2022. The Author(s).)
- Published
- 2022
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26. Investigation of Maternal Diet and FADS1 Polymorphism Associated with Long-Chain Polyunsaturated Fatty Acid Compositions in Human Milk.
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Niwa S, Kawabata T, Shoji K, Ogata H, Kagawa Y, Nakayama K, Yanagisawa Y, Iwamoto S, Tatsuta N, Asato K, Arima T, Yaegashi N, and Nakai K
- Subjects
- Animals, Arachidonic Acid analysis, Diet, Docosahexaenoic Acids analysis, Eicosapentaenoic Acid analysis, Fatty Acids analysis, Female, Fishes, Humans, Delta-5 Fatty Acid Desaturase genetics, Lactation, Milk, Human chemistry
- Abstract
Increasing the amount of long-chain polyunsaturated fatty acids (LCPUFA) in human milk is an important strategy for infant growth and development. We investigated the associations of LCPUFA compositions in human milk with maternal diet (especially fish and shellfish intake), with fatty acid Δ5 desaturase gene (FADS1) polymorphisms, and with gene-diet interactions. The present study was performed as part of an adjunct study of the Japan Environment and Children’s Study. The participants were 304 lactating females, who provided human milk 6−7 months after delivery. Fatty acids in human milk were analyzed by gas chromatography, and dietary surveys were conducted using a brief self-administered diet history questionnaire. We also analyzed a single nucleotide polymorphism of FADS1 (rs174547, T/C). There was a significant difference in arachidonic acid (ARA) composition in human milk among the genotype groups, and the values were decreasing in the order of TT > TC > CC. The concentrations of eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) were also different between TT and CC genotype, indicating a tendency for decreasing values in the same order. The composition of ARA showed significant gene−dietary interactions in multiple regression analysis, and the positive correlation between fish and shellfish intake and ARA composition in human milk was significant only in the CC genotype. Moreover, the factor most strongly associated with EPA and DHA composition in human milk was fish and shellfish intake. Therefore, it was suggested that increasing fish and shellfish intake in mothers may increase EPA and DHA composition in human milk, while increasing fish and shellfish intake in CC genotype mothers may lead to increased ARA composition in human milk.
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- 2022
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27. Intra- and Inter-Day Element Variability in Human Breast Milk: Pilot Study.
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Iwai K, Iwai-Shimada M, Asato K, Nakai K, Kobayashi Y, Nakayama SF, and Tatsuta N
- Abstract
For infants in the first months of life, breast milk is a complete source of nutrition; however, it can also contain elements that are harmful to the infant. It is therefore critical for infant health to characterize breast milk. The aim of this study was to determine the intra- and inter-day variation of elements in breast milk, for which there is currently limited information, as a pilot study for a larger study. Firstly, we developed a simple and robust analytical method for the determination of multiple elements in breast milk. It was accurate (accuracy ranged from 98% to 107%) for measurement of 26 elements in breast milk by quadrupole inductively coupled plasma-mass spectrometry. Intra- and inter-day variation of elements, protein, and fat in breast milk was determined by analyzing breast milk collected from 11 women at 12 sampling points over three days and calculating intraclass correlation coefficients. Intraclass correlation coefficients showed that while some elements were consistent across time points (e.g., Sr, Ca, and Cu), others showed very high variability (e.g., As, Cd, and Ni). Correlation analyses between elements in breast milk showed strong relationships between those including Fe and Mo, Ca and Sr, and Cd and Fe.
- Published
- 2022
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28. Societal Costs of a Measles Outbreak.
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Pike J, Melnick A, Gastañaduy PA, Kay M, Harbison J, Leidner AJ, Rice S, Asato K, Schwartz L, and DeBolt C
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- Child, Costs and Cost Analysis, Humans, Measles epidemiology, Measles Vaccine, Public Health economics, Quarantine economics, Washington epidemiology, Disease Outbreaks economics, Measles economics
- Abstract
Background and Objectives: Between December 31, 2018, and April 26, 2019, 72 confirmed cases of measles were identified in Clark County. Our objective was to estimate the economic burden of the measles outbreak from a societal perspective, including public health response costs as well as direct medical costs and productivity losses of affected individuals., Methods: To estimate costs related to this outbreak from the societal perspective, 3 types of costs were collected or estimated: public health response (labor, material, and contractor costs used to contain the outbreak), direct medical (third party or patient out-of-pocket treatment costs of infected individuals), and productivity losses (costs of lost productivity due to illness, home isolation, quarantine, or informal caregiving)., Results: The overall societal cost of the 2019 Clark County measles outbreak was ∼$3.4 million ($47 479 per case or $814 per contact). The majority of the costs (∼$2.3 million) were incurred by the public health response to the outbreak, followed by productivity losses (∼$1.0 million) and direct medical costs (∼$76 000)., Conclusions: Recent increases in incident measles cases in the United States and across the globe underscore the need to more fully understand the societal cost of measles cases and outbreaks and economic consequences of undervaccination. Our estimates can provide valuable inputs for policy makers and public health stakeholders as they consider budget determinations and the substantial value associated with increasing vaccine coverage and outbreak preparedness as well as the protection of society against vaccine-preventable diseases, such as measles, which are readily preventable with high vaccination coverage., Competing Interests: POTENTIAL CONFLICT OF INTEREST: The authors have indicated they have no potential conflicts of interest to disclose., (Copyright © 2021 by the American Academy of Pediatrics.)
- Published
- 2021
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29. Intestinal flow after anastomotic operations in neonates.
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Ito Y, Asato K, Cho I, Sakai Y, Iwano K, Tainaka T, and Uchida H
- Subjects
- Anastomosis, Surgical, Humans, Infant, Newborn, Hydrodynamics
- Abstract
Stagnation of contents at the anastomotic site for intestinal flows after anastomotic operation is a critical issue in neonates. Although various anastomosis methods have been developed, in the clinical field, poor passage at the anastomotic site in cases of jejunal atresia is still observed. A CFD study was carried out to clarify the reasons for the stagnation and to find favorable anastomosis methods from a fluid dynamical point of view. Direct numerical simulations were performed using OpenFOAM. The boundaries of the computational domain were peristaltically moved to reproduce flow. The results reveal that the peristaltic motion on the distal side dominates the flow and that on the proximal side has a negligible influence. In particular, the contents do not pass the anastomotic site when the peristaltic motion on the distal side is not active. The flow rate as a measure of the driving force of the flow on the proximal side is large when the amplitude of the peristaltic motion is large and the diameter is small. It was also found that anastomosis methods do not affect flow resistance., Competing Interests: Declaration of Competing Interest None declared., (Copyright © 2019 Elsevier Ltd. All rights reserved.)
- Published
- 2020
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30. Publisher Correction: Cretaceous amber fossils highlight the evolutionary history and morphological conservatism of land snails.
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Hirano T, Asato K, Yamamoto S, Takahashi Y, and Chiba S
- Abstract
An amendment to this paper has been published and can be accessed via a link at the top of the paper.
- Published
- 2019
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31. Cretaceous amber fossils highlight the evolutionary history and morphological conservatism of land snails.
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Hirano T, Asato K, Yamamoto S, Takahashi Y, and Chiba S
- Subjects
- Animal Shells anatomy & histology, Animals, Phylogeny, Snails classification, Biological Evolution, Fossils, Snails anatomy & histology
- Abstract
Other than hard bones and shells, it is rare for soft tissues to fossilize, but occasionally they are well-preserved in amber. Here, we focus on both modern and fossilized species of the land snail superfamily Cyclophoroidea. Phylogenetic relationships within the Cyclophoroidea were previously studied using extant species, but timing of divergence within the group remains unclear. In addition, it is difficult to observe morphological traits such as the chitinous operculum and periostracum of fossil snails due to their poor preservation potential. Here we describe nine species including a new genus and five new species of well-preserved fossil cyclophoroideans from the mid-Cretaceous Burmese amber. These fossils include not only the shell, but also the chitinous operculum and periostracum, soft body, and excrements. We present the first estimation of divergence time among cyclophoroidean families using fossil records and molecular data, suggesting extreme morphological conservatism of the Cyclophoroidea for nearly 100 million years.
- Published
- 2019
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32. Subchorionic hematoma occurs more frequently in in vitro fertilization pregnancy.
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Asato K, Mekaru K, Heshiki C, Sugiyama H, Kinjyo T, Masamoto H, and Aoki Y
- Subjects
- Adult, Chorion, Embryo Transfer methods, Female, Humans, Infertility etiology, Parity, Pregnancy, Retrospective Studies, Risk Factors, Embryo Transfer adverse effects, Fertilization in Vitro adverse effects, Hematoma epidemiology, Pregnancy Complications, Hematologic epidemiology
- Abstract
Objective: Obstetric complications occur more frequently in pregnancies after in vitro fertilization (IVF). We attempted to determine the correlation between subchorionic hematoma and IVF pregnancies., Study Design: We analyzed 194 pregnancies achieved by infertility treatment between January 2008 and February 2012 at our hospital. Among these, 67 were achieved by IVF and 127 by non-IVF approaches. We compared the frequency of subchorionic hematoma between the groups and examined the risk factors for subchorionic hematoma in the IVF group., Results: No significant differences regarding age and the number of uterine surgery were observed between the groups. The duration of infertility was longer, parity and the rate of luteal support were higher in the IVF group compared with that in the non-IVF group. The frequency of subchorionic hematoma was significantly higher in the IVF group (22.4%) than that in the non-IVF group (11%) (P=0.035). Univariate analysis in the IVF group demonstrated that frozen-thawed embryo transfer (OR, 6.18; 95% CI, 1.7-22.4), parity≥1 (OR, 3.67; 95% CI, 1.0-13.2) and blastocyst transfer (OR, 3.75; 95% CI, 1.1-13.3) were risk factors for the subchorionic hematoma., Conclusion: The frequency of subchorionic hematoma is high in IVF pregnancies, and frozen-thawed embryo transfer, parity≥1, and blastocyst transfer may contribute to subchorionic hematoma onset., (Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.)
- Published
- 2014
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33. Endometriosis and pregnancy outcome: are pregnancies complicated by endometriosis a high-risk group?
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Mekaru K, Masamoto H, Sugiyama H, Asato K, Heshiki C, Kinjyo T, and Aoki Y
- Subjects
- Adult, Apgar Score, Birth Weight, Case-Control Studies, Chorion blood supply, Cohort Studies, Female, Gestational Age, Humans, Infant, Newborn, Ovulation Induction statistics & numerical data, Pregnancy, Pregnancy Outcome, Retrospective Studies, Abortion, Spontaneous epidemiology, Cesarean Section statistics & numerical data, Endometriosis epidemiology, Hematoma epidemiology, Hypertension, Pregnancy-Induced epidemiology, Pregnancy Complications epidemiology, Premature Birth epidemiology
- Abstract
Objectives: Increased incidence of preterm birth, pregnancy-induced hypertension (PIH) and small-for-gestational-age (SGA) babies have been reported in women with endometriosis, but the study populations included women in whom a definitive diagnosis was not attainable, and women who conceived via in vitro fertilization/embryo transfer (IVF/ET), which, in itself, is a risk factor for adverse pregnancy outcome. Thus there is a lack of consensus on the effects of endometriosis on pregnancy outcome. This study compared the pregnancy outcomes of women with or without a definitive diagnosis of endometriosis on laparoscopy., Study Design: Retrospective comparison of pregnancy outcomes of 108 women who underwent managed delivery of pregnancies established after laparoscopic investigation of infertility. Women with factors known to affect pregnancy outcome, such as age ≥41 years, conception via IVF/ET and multiple births, were excluded. Forty-nine of the study participants had endometriosis (En+ group) and 59 participants did not have endometriosis (En- group)., Results: There were no significant differences in mean (±standard deviation) age (33±3.8 vs 33.6±4.1 years), history of miscarriage, history of preterm birth and history of PIH between the two groups. Ovulation induction was used for infertility treatment in 26.5% of the En+ group and 30.5% of the En- group, and artificial insemination was used in 30.6% of the En+ group and 32.2% of the En- group. Regarding pregnancy outcomes, no significant differences in miscarriage (18.4% vs 18.6%), subchorionic haematoma (5.0% vs 2.1%), preterm birth (7.5% vs 8.3%), PIH (15.0% vs 12.5%), caesarean section (32.5% vs 22.9%), gestational age at delivery (38.9±1.5 vs 38.8±1.7 weeks), birth weight (3013.3±480 vs 2934.5±639.5g) and SGA babies (2.5% vs 2.1%) were found between the En+ and En- groups. Placental abruption did not occur in either group. One neonate had trisomy 21 in the En+ group, and one woman had gestational diabetes in the En- group., Conclusion: Endometriosis may not affect pregnancy outcome, but there is a need for a large prospective study., (Copyright © 2013 Elsevier Ireland Ltd. All rights reserved.)
- Published
- 2014
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34. Long-term results and prognostic factors in patients with stage III-IVA squamous cell carcinoma of the cervix treated with concurrent chemoradiotherapy from a single institution study.
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Kudaka W, Nagai Y, Toita T, Inamine M, Asato K, Nakamoto T, Wakayama A, Ooyama T, Tokura A, Murayama S, and Aoki Y
- Subjects
- Adult, Aged, Brachytherapy, Carcinoma, Squamous Cell pathology, Chemoradiotherapy adverse effects, Cisplatin administration & dosage, Cisplatin adverse effects, Combined Modality Therapy, Disease-Free Survival, Drug-Related Side Effects and Adverse Reactions pathology, Female, Humans, Middle Aged, Neoplasm Staging, Prognosis, Radiotherapy Dosage, Risk Factors, Treatment Outcome, Uterine Cervical Neoplasms pathology, Carcinoma, Squamous Cell drug therapy, Carcinoma, Squamous Cell radiotherapy, Uterine Cervical Neoplasms drug therapy, Uterine Cervical Neoplasms radiotherapy
- Abstract
Background: We evaluated the longer-term efficacy and safety of concurrent chemoradiotherapy (CCRT) incorporating high-dose-rate intracavitary brachytherapy (HDR-ICBT) with a lower cumulative radiotherapy (RT) protocol and analyzed prognostic risk factors for survival among patients with FIGO stage III-IVA squamous cell carcinoma (SCC) of the cervix., Patients and Methods: Ninety-nine patients with FIGO stage III-IVA SCC of the cervix between 1997 and 2008 were treated with CCRT using cisplatin 20 mg/m(2) for 5 days every 3 weeks or 40 mg/m(2) weekly. Acute and late toxicities were evaluated. Overall survival (OS) and disease-free survival (DFS) were estimated by the Kaplan-Meier method. The Cox proportional hazard model was used for multivariate analysis., Results: Median age was 53.5 years. Median follow-up period was 58 months (range 6-170 months). Pathologically complete response was achieved in 93 patients (96.9%). The 5-year OS and DFS were 72.0 and 69.3%, respectively. The 5-year local and distant DFS were 83.0 and 75.1%, respectively. Thirty-one patients (31.3%) experienced recurrence. Multivariate analysis showed that tumor size and pretreatment hemoglobin level remained an independent risk factor for OS and DFS. Acute toxicity was moderate. In terms of late adverse effects, 2 patients (2.0%) suffered from grade 4 late intestinal toxicity because of radiation enterocolitis, with both requiring intestinal surgery., Conclusions: Our study demonstrates that the CCRT schedule in patients with FIGO stage III-IVA SCC is efficacious and safe. In addition, the assessment of tumor size and pretreatment anemia can provide valuable prognostic information.
- Published
- 2013
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35. Effects of early endometriosis on IVF-ET outcomes.
- Author
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Mekaru K, Yagi C, Asato K, Masamoto H, Sakumoto K, and Aoki Y
- Subjects
- Adult, Endometriosis pathology, Female, Humans, Infertility, Female therapy, Pregnancy, Pregnancy Rate, Retrospective Studies, Statistics, Nonparametric, Treatment Outcome, Embryo Transfer statistics & numerical data, Endometriosis complications, Fertilization in Vitro statistics & numerical data, Infertility, Female etiology
- Abstract
There have been very few reports on the outcomes of in vitro fertilization and embryo transfer (IVF-ET) in women with stage I/II endometriosis. The objective of this study was to investigate IVF-ET outcomes in women with early-stage endometriosis. We enrolled 35 women less than 40 years with unexplained infertility who underwent IVF-ET into the study. We compared 18 women with stage I/II endometriosis according to the revised American Society for Reproductive Medicine classification for endometriosis, who underwent 39 IVF-ET cycles (En (+) group) with 17 women without endometriosis who underwent 41 IVF-ET cycles (En (-) group). Higher requirements of total gonadotropin, a lower percentage of high-quality embryos of all fertilized eggs (9.0% vs. 16.3%), a relatively lower pregnancy rate (33.3% vs. 41.5%), and a lower live birth rate (25.6% vs. 34.1%) were observed in the En (+) group. Although no significant effect on IVF-ET outcome was observed, ovarian response may be decreased in women with stage I/II endometriosis. Considering the decreased number of high-quality embryos in the En (+) group, stage I/II endometriosis may have detrimental effects on embryo quality.
- Published
- 2013
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- View/download PDF
36. A surgical navigation system for aortic vascular surgery: a practical approach.
- Author
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Uematsu M, Asato K, Ichihashi T, Umezu M, Nakaoka R, Matsuoka A, Aomi S, Iimura H, Suzuki T, Muragaki Y, and Iseki H
- Subjects
- Aortic Aneurysm, Thoracic surgery, Equipment Design, Humans, Surgery, Computer-Assisted instrumentation, Vascular Surgical Procedures instrumentation, Aorta surgery, Phantoms, Imaging, Surgery, Computer-Assisted methods, Vascular Surgical Procedures methods
- Abstract
In aortic vascular surgery, a navigation system must represent the anatomical map of individual patient in order to detect the important artery. To provide a proper fit for positions along the dorsoventral axis, the spinous process was added to a currently used anatomical point set consisting of four anterior body landmarks. In addition, we attempted to reduce the registration error by compensating for alignment errors resulting from variations in tissue thickness at each landmark. The alignment values were examined using a human phantom consisting of a skeleton model with subcutaneous tissue in the semilateral position. Using this method, a phantom simulation and five clinical trials were performed. Target errors were evaluated at the orifice of the intercostal artery. In the phantom simulation, the error at the target point was 4.1 ± 2.7 mm. However, for one patient undergoing thoracoabdominal aortic aneurysm replacement surgery, the target error was 8.0 mm using the proposed method.
- Published
- 2013
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37. Hysteroscopic tubal catheterization under laparoscopy for proximal tubal obstruction.
- Author
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Mekaru K, Yagi C, Asato K, Masamoto H, Sakumoto K, and Aoki Y
- Subjects
- Adult, Fallopian Tube Diseases diagnosis, Fallopian Tube Diseases diagnostic imaging, Fallopian Tube Patency Tests, Female, Humans, Hysterosalpingography, Insemination, Artificial, Laparoscopy, Middle Aged, Pregnancy, Pregnancy Outcome, Young Adult, Catheterization, Fallopian Tube Diseases therapy, Fallopian Tubes, Hysteroscopy
- Abstract
Purpose: The purpose of this study was to investigate the fertility outcomes of infertile patients having proximal tubal obstruction treated with hysteroscopic tubal catheterization (HCT) for recanalization under diagnostic laparoscopy., Methods: From January 2000 to December 2008, diagnostic laparoscopy was used to assess the tubal status of 61 patients with unilateral or bilateral proximal tubal obstruction, as confirmed by hysterosalpingography. Among them, 35 patients with tubal obstruction confirmed by chromopertubation under laparoscopy subsequently underwent HCT. The pregnancy outcomes and success rates of recanalization were investigated., Results: In the 35 patients with confirmed tubal obstruction, HCT was performed in 54 fallopian tubes. The success rate of recanalization was 25.9% (14/54) per tube and 37.1% (13/35) per patient. Of the patients in whom tubal patency was restored, 4 achieved pregnancy, including 1 tubal pregnancy and 1 miscarriage. Among the 61 patients, excluding 14 who underwent in vitro fertilization-embryo transfer (IVF-ET) after laparoscopy, 13 were pregnant (27.7%), 9 gave live births, 1 had tubal pregnancy, and 3 had miscarriages., Conclusions: HCT under laparoscopy is an option for couples with tubal infertility who do not prefer IVF-ET.
- Published
- 2011
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38. Comparison between the gonadotropin-releasing hormone antagonist protocol and the gonadotropin-releasing hormone agonist long protocol for controlled ovarian hyperstimulation in the first in vitro fertilization-embryo transfer cycle in an unspecified population of infertile couples.
- Author
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Mekaru K, Yagi C, Asato K, Masamoto H, Sakumoto K, and Aoki Y
- Abstract
Purpose: We aimed to compare the efficacy of a gonadotropin-releasing hormone (GnRH) antagonist protocol and a GnRH agonist long protocol used in the first in vitro fertilization-embryo transfer (IVF-ET) cycle in an unspecified population of infertile couples., Methods: Fifty and 34 patients were treated with a GnRH agonist long protocol (agonist group) and GnRH antagonist protocol (antagonist group), respectively, in the first treatment cycle. The primary and secondary outcome measures were cumulative live birth rates after fresh and cryopreserved-thawed ETs and incidence of grades II and III ovarian hyperstimulation syndrome (OHSS), respectively., Results: No significant differences were observed in clinical pregnancy rates (38.0 vs. 32.4%) and live birth rates (22.0 vs. 23.5%), which included both fresh and cryopreserved-thawed ETs, between the 2 groups. However, the incidence of grade III OHSS was significantly lower with the GnRH antagonist protocol than the GnRH agonist long protocol., Conclusions: Used in the first IVF-ET cycle in an unspecified population of infertile patients, the GnRH antagonist protocol showed the same clinical outcome as the GnRH agonist long protocol.
- Published
- 2011
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39. Specific blockade of the ERK pathway inhibits the invasiveness of tumor cells: down-regulation of matrix metalloproteinase-3/-9/-14 and CD44.
- Author
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Tanimura S, Asato K, Fujishiro SH, and Kohno M
- Subjects
- Benzamides metabolism, Enzyme Activation, Enzyme Inhibitors metabolism, Humans, Matrix Metalloproteinases, Membrane-Associated, Mitogen-Activated Protein Kinases metabolism, Phenotype, Tumor Cells, Cultured, Down-Regulation physiology, Hyaluronan Receptors metabolism, MAP Kinase Signaling System physiology, Matrix Metalloproteinase 3 metabolism, Matrix Metalloproteinase 9 metabolism, Metalloendopeptidases metabolism, Mitogen-Activated Protein Kinases antagonists & inhibitors, Neoplasm Invasiveness
- Abstract
Elevated expression of matrix metalloproteinases (MMPs) is associated with increased metastatic potential in many tumor cells. As activation of the ERK pathway has been linked to the expression of MMP-9, we examined a possible correlation between ERK activation, MMP-9 expression, and invasive phenotype in human tumor cells. Activation state of the ERK pathway in tumor cells was well correlated with the invasive phenotype, which was determined by the ability of cells to invade through reconstituted extracellular matrix. Elevated expression of MMP-9 as well as of MMP-3, MMP-14, and CD44 was observed in tumor cells in which constitutive activation of the ERK pathway is detected. Blockade of the ERK pathway by treatment with PD184352, a specific and powerful inhibitor of mitogen-activated protein (MAP) kinase/ERK kinase (MEK), suppressed the expression of MMP-3, MMP-9, MMP-14, and CD44, and inhibited markedly the invasiveness of tumor cells. These results imply that, in addition to anti-proliferative effects, specific blockade of the ERK pathway is expected to result in anti-metastatic effects in tumor cells.
- Published
- 2003
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40. ERK pathway positively regulates the expression of Sprouty genes.
- Author
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Ozaki K, Kadomoto R, Asato K, Tanimura S, Itoh N, and Kohno M
- Subjects
- Animals, Cell Line, Enzyme Activation drug effects, Enzyme Activation physiology, Enzyme Inhibitors pharmacology, Feedback physiology, Fibroblast Growth Factor 2 pharmacology, Fibroblasts drug effects, Fibroblasts metabolism, Humans, Mice, Mitogen-Activated Protein Kinase 1 antagonists & inhibitors, Mitogen-Activated Protein Kinase 1 metabolism, Mitogen-Activated Protein Kinase 3, Mitogen-Activated Protein Kinases antagonists & inhibitors, Mitogens pharmacology, Neoplasms metabolism, Phosphoinositide-3 Kinase Inhibitors, Proto-Oncogene Proteins c-raf metabolism, Signal Transduction drug effects, p38 Mitogen-Activated Protein Kinases, Drosophila Proteins, Gene Expression Regulation physiology, Insect Proteins genetics, Insect Proteins metabolism, Membrane Proteins, Mitogen-Activated Protein Kinases metabolism, Signal Transduction physiology
- Abstract
Sprouty was originally identified as an inhibitor of Drosophila development-associated receptor tyrosine kinase (RTK) signaling. Although RTK signaling has been shown to induce Sprouty gene expression, the precise induction pathway downstream of RTK remains unclear. As RTK signaling pathway includes activation of extracellular signal-regulated kinases (ERKs), we have examined a correlation between activation of ERKs and induction of Sprouty gene expression. All reagents which induce the activation of ERKs induce Sprouty gene expression; these agents include not only growth factors which bind to RTK but also phorbol 12-myristate-13-acetate and active Raf-1 kinase. Furthermore, the Sprouty gene expression induced by all those agents is totally suppressed when the cells are pretreated with specific inhibitors of ERK kinase (MEK). Human tumor cells which exhibit constitutive activation of ERKs show elevated expression of Sprouty genes, which is abolished by treatment of these cells with MEK inhibitors. All these findings clearly indicate that Sprouty gene expression is positively regulated by the ERK pathway downstream of RTK., (Copyright 2001 Academic Press.)
- Published
- 2001
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41. Mouse ULK2, a novel member of the UNC-51-like protein kinases: unique features of functional domains.
- Author
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Yan J, Kuroyanagi H, Tomemori T, Okazaki N, Asato K, Matsuda Y, Suzuki Y, Ohshima Y, Mitani S, Masuho Y, Shirasawa T, and Muramatsu M
- Subjects
- Amino Acid Sequence, Animals, Base Sequence, Binding Sites, COS Cells, Caenorhabditis elegans, Chromosome Mapping, Cloning, Molecular, DNA, Complementary, Gene Expression, Mice, Molecular Sequence Data, Protein Serine-Threonine Kinases metabolism, Protein Structure, Tertiary, RNA, Messenger, Rats, Sequence Homology, Amino Acid, Tissue Distribution, Caenorhabditis elegans Proteins, Protein Serine-Threonine Kinases chemistry, Protein Serine-Threonine Kinases genetics
- Abstract
The UNC-51 serine/threonine kinase of C. elegans plays an essential role in axonal elongation, and unc-51 mutants exhibit uncoordinated movements. We have previously identified mouse and human cDNAs encoding UNC-51-like kinase (ULK1). Here we report the identification and characterization of the second murine member of this kinase family, ULK2. Mouse ULK2 cDNA encodes a putative polypeptide of 1033 aa which has an overall 52% and 33% amino acid identity to ULK1 and UNC-51, respectively. ULKs and UNC-51 share a typical domain structure of an amino-terminal kinase domain, a central proline/serine rich (PS) domain, and a carboxy-terminal (C) domain. Northern blot analysis showed that ULK2 mRNA is widely expressed in adult tissues. In situ hybridization analysis indicated that ULK2 mRNA is ubiquitously localized in premature as well as mature neurons in developing nervous system. ULK2 gene was mapped to mouse chromosome 11B1.3 and rat chromosome 10q23 by FISH. HA-tagged ULK2 expressed in COS7 cells had an apparent molecular size of approximately 150 kDa and was autophosphorylated in vitro. Truncation mutants suggested that the autophosphorylation occurs in the PS domain. Although expression of ULK2 failed to rescue unc-51 mutant of C. elegans, a series of ULK2/UNC-51 chimeric kinases revealed that function of the kinase and PS domains are conserved among species, while the C domain acts in a species-specific manner. These results suggest that ULK2 is involved in a previously uncharacterized signaling pathway in mammalian cells.
- Published
- 1999
- Full Text
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42. SMARTWheels: development and testing of a system for measuring manual wheelchair propulsion dynamics.
- Author
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Asato KT, Cooper RA, Robertson RN, and Ster JF
- Subjects
- Adult, Computer-Aided Design statistics & numerical data, Equipment Design statistics & numerical data, Female, Humans, Male, Mathematics, Physical Phenomena, Physics, Software Design, Wheelchairs statistics & numerical data
- Abstract
The purpose of this project was to develop a system for dynamically sensing pushrim propulsion forces and torques and to collect kinetic data with the device. A system was developed to detect the forces and torques applied to the wheelchair pushrim, record, store, and process the measured data, and display the kinetic information for analysis. Ten adults, including four male wheelchair users, three ambulatory men, and three ambulatory women, pushed a wheelchair with the SMARTWheel on a dynamometer while their kinematics were videotaped. The kinetic data collected with our wheel were correlated with stick figure representations of digitized kinematic data obtained through video analysis. The close agreement between the kinetic results and the Kinematic results provided a temporal validation of the ability of the wheel to detect forces and torques applied to the wheelchair pushrim. The recorded forces and torques were in agreement with previously reported magnitudes.
- Published
- 1993
- Full Text
- View/download PDF
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