Kayo Tanaka

Dr. Kayo Tanaka

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Research Focus & Metrics

Academic Career Length

11Years (2016-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

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1 January 2016 in Circulation Journal
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KTKayo Tanaka
Kayo Tanaka
HTHiroaki Tanaka
Hiroaki Tanaka
CKChizuko Kamiya
Chizuko Kamiya
SKShinji Katsuragi
Shinji Katsuragi
MSMasami Sawada
Masami Sawada
TITomoaki Ikeda
Tomoaki Ikeda
The effects of β-adrenergic blockers on the fetus are not well understood. We analyzed the maternal and neonatal outcomes of β-adrenergic blocker treatment during pregnancy to identify the risk of fetal growth restriction (FGR). We retrospectively reviewed 158 pregnancies in women with cardiovascular disease at a single center. Maternal and neonatal outcomes were analyzed in 3 categories: the carvedilol (α/β-adrenergic blocker; α/β group, n=13); β-adrenergic blocker (β group, n=45), and control groups (n=100). Maternal outcome was not significantly different between the groups. FGR occurred in 1 patient (7%) in the α/β group, in 12 (26%) in the β group, and in 3 (3%) in the control group; there was a significant difference between the incidence of FGR between the β group and control group (P<0.05). The β group included propranolol (n=22), metoprolol (n=12), atenolol (n=6), and bisoprolol (n=5), and the individual incidence of FGR with these medications was 36%, 17%, 33%, and 0%, respectively. As a group, β-adrenergic blockers were significantly associated with FGR, although the incidence of FGR varied with individual β-blocker. Carvedilol, an α/β-adrenergic blocker, had no association with FGR. More controlled studies are needed to fully establish such associations. (Circ J 2016; 80: 2221-2226).

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SMShintaro Maki
Shintaro Maki
Hiroaki TanakaHiroaki Tanaka
Hiroaki Tanaka
MTMakoto Tsuji
Makoto Tsuji
FFFumi Furuhashi
Fumi Furuhashi
SMShoichi Magawa
Shoichi Magawa
TITomoaki Ikeda
Tomoaki Ikeda
Tadalafil is a phosphodiesterase 5 (PDE5) inhibitor with a long half-life, high selectivity, and rapid onset of action. Because the safety of using PDE5 inhibitors as therapeutic agents for fetal growth restriction (FGR) has been a problem worldwide, this paper primarily focuses on the safety assessments performed in the Tadalafil Treatment for Fetuses with Early-Onset Growth Restriction (TADAFER) II population. Neonatal and maternal adverse events were analyzed, in addition to fetal, neonatal, and infant death cases, six months after stopping the trial. Eighty-nine pregnant women with FGR were studied between September 2016 and March 2018 (45 and 44 in the tadalafil and conventional treatment groups, respectively). Seven (16%) deaths (four fetal, one neonatal, and two infant) in the control group, whereas only one neonatal death occurred in the tadalafil group. Although headache, facial flushing, and nasal hemorrhage occurred more frequently in the tadalafil group, these symptoms were Grade 1 and transient. In conclusion, this trial showed that tadalafil decreased the fetal and infant deaths associated with FGR. This is thought to be primarily due to pregnancy prolongation. Further studies are warranted to evaluate the efficacy of tadalafil in treating early-onset FGR.

1 January 2020 in Biochemical and Biophysical Research Communications
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Journal Article
Closed access
ASAkiyo Sekimoto
Akiyo Sekimoto
KTKayo Tanaka
Kayo Tanaka
YHYamato Hashizume
Yamato Hashizume
ESEmiko Sato
Emiko Sato
HSHiroshi Sato
Hiroshi Sato
NTNobuyuki Takahashi
Nobuyuki Takahashi

15 January 2020 in Medicina
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Hiroaki TanakaHiroaki Tanaka
Hiroaki Tanaka
KTKayo Tanaka
Kayo Tanaka
KOKazuhiro Osato
Kazuhiro Osato
HKHideto Kusaka
Hideto Kusaka
YMYuka Maegawa
Yuka Maegawa
TITomoaki Ikeda
Tomoaki Ikeda
Background: To evaluate maternal and neonatal outcomes of assisted reproductive technology (ART). Materials and Methods: Pregnant women registered from 2015 through 2017 (n = 6994) at five perinatal centers that managed high-risk pregnancies in Mie, Japan, retrospectively. Rates of preterm birth (<37 gestational weeks), early onset preeclampsia (<34 gestational weeks), late onset preeclampsia (≥34 gestational weeks), low-lying placenta, placenta previa, placenta accreta, placental abruption, atonic bleeding, uterine rupture, and amniotic fluid embolism after ART were evaluated. ART was defined as in vitro fertilization and micro-fertilization. Fisher’s exact test, Mann–Whitney’s U test, and logistic regression analysis were used to analyze the data. Results: Rates of obstetrical complications including low-lying placenta, placenta previa, placenta accreta, and atonic bleeding were increased with ART compared to those with the control. Particularly, ART was associated with a significantly increased rate of placenta accreta (adjusted odds ratio: 7.35, 95% confidence interval (CI): 3.20–16.6) and significantly decreased rate of placental abruption (adjusted odds ratio: 0.24, 95% CI: 0.07–0.61). Conclusions: This study showed that ART may reduce placental abruption and increase placenta previa. There is a possibility that the placenta attaches deeper in the myometrium because of ART.

28 July 2021 in Brain Sciences
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Hiroaki TanakaHiroaki Tanaka
Hiroaki Tanaka
SKShinji Katsuragi
Shinji Katsuragi
Junichi HasegawaJunichi Hasegawa
Junichi Hasegawa
KTKayo Tanaka
Kayo Tanaka
MNMasamitsu Nakamura
Masamitsu Nakamura
TITomoaki Ikeda
Tomoaki Ikeda
Sudden unexpected death in epilepsy (SUDEP) is defined as the sudden death of a patient with epilepsy in the absence of an anatomic or toxicologic cause. Whether pregnancy is a risk factor for SUDEP is unclear. Using data submitted to the Japan Association of Obstetricians and Gynecologists (JAOG), which has been collating information regarding all maternal deaths in Japan since 2000, this study evaluated maternal mortality data from 2010 to 2019 to evaluate the current circumstances of maternal death related to SUDEP in Japan. Six women died due to SUDEP during this period; the maternal mortality rate related to SUDEP was 0.066/100,000 individuals. Two women each died during the second trimester, third trimester, and postpartum period. Four and two women were receiving monotherapy and no therapy with anti-epileptic drugs, respectively. The duration of epilepsy was ≤15 years in three women, >15 years in one woman, and unknown in two women. This study furthers our understanding of the prevalence of maternal deaths due to SUDEP in Japan. Further studies are needed to confirm whether pregnancy is a risk factor for SUDEP.

Verified
Journal Article
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KTKayo Tanaka
Kayo Tanaka
Hiroaki TanakaHiroaki Tanaka
Hiroaki Tanaka
RTRyota Tachibana
Ryota Tachibana
KYKento Yoshikawa
Kento Yoshikawa
TKTakuya Kawamura
Takuya Kawamura
TITomoaki Ikeda
Tomoaki Ikeda
Fetal growth restriction (FGR) is a major cause of poor perinatal outcomes. Although several studies have been conducted to improve the prognosis of FGR in infants, no effective intrauterine treatment method has been established. This study aimed to use tadalafil, a phosphodiesterase 5 inhibitor (PDE5) inhibitor, as a novel intrauterine treatment and conducted several basic and clinical studies. The study investigated the effects of tadalafil on placental mTOR signaling. Tadalafil was administered to mice with L-NG-nitroarginine methyl ester (L-NAME)-induced FGR and associated preeclampsia (PE). Placental phosphorylated mTOR (p-mTOR) signaling was assessed by fluorescent immunohistochemical staining and Western blotting. The expression of p-mTOR was significantly decreased in mice with FGR on 13 days post coitum (d.p.c.) but recovered to the same level as that of the control on 17 d.p.c. following tadalafil treatment. The results were similar for 4E-binding protein 1 (4E-BP1) and S6 ribosomal (S6R) protein, which act downstream in the mTOR signaling pathway. We demonstrate that the tadalafil treatment of FGR in mice improved placental mTOR signaling to facilitate fetal growth. Our study provides the key mechanistic detail about the mode of action of tadalafil and thus would be helpful for future clinical studies on FGR.