MEMasayuki Endo

Masayuki Endo

*This is an algorithmically generated author record based on publicly available information.

Current Organizations / Institutes

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Previous Organizations / Institutes

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Masayuki Endo has a total of 92 co-authors. Here are the top co-authors by number of shared publications:


Latest Publications

  • Open Access

    Explainable Machine Learning Classification to Identify Vulnerable Groups Among Parenting Mothers: Web-Based Cross-Sectional Questionnaire Study

    by Akiko Hanai, Tetsuo Ishikawa, Shoko Sugao, Makoto Fujii, Kei Hirai, Hiroko Watanabe, Masayo Matsuzaki, Goji Nakamoto, Toshihiro Takeda, Yasuji Kitabatake, et al.

    Background: One life event that requires extensive resilience and adaptation is parenting. However, resilience and perceived support in child-rearing vary, making the real-world situation unclear, even with postpartum checkups. Objective: This study aimed to explore the psychosocial status of mothers during the child-rearing period from newborn to toddler, with a classifier based on data on the resilience and adaptation characteristics of mothers with newborns. Methods: A web-based cross-sectional survey was conducted. Mothers with newborns aged approximately 1 month (newborn cohort) were analyzed to construct an explainable machine learning classifier to stratify parenting-related resilience and adaptation characteristics and identify vulnerable populations. Explainable k-means clustering was used because of its high explanatory power and applicability. The classifier was applied to mothers with infants aged 2 months to 1 year (infant cohort) and mothers with toddlers aged >1 year to 2 years (toddler cohort). Psychosocial status, including depressed mood assessed by the Edinburgh Postnatal Depression Scale (EPDS), bonding assessed by the Postpartum Bonding Questionnaire (PBQ), and sleep quality assessed by the Pittsburgh Sleep Quality Index (PSQI) between the classified groups, was compared. Results: A total of 1559 participants completed the survey. They were split into 3 cohorts, comprising populations of various characteristics, including parenting difficulties and psychosocial measures. The classifier, which stratified participants into 5 groups, was generated from the self-reported scores of resilience and adaptation in the newborn cohort (n=310). The classifier identified that the group with the greatest difficulties in resilience and adaptation to a child’s temperament and perceived support had higher incidences of problems with depressed mood (relative prevalence [RP] 5.87, 95% CI 2.77-12.45), bonding (RP 5.38, 95% CI 2.53-11.45), and sleep quality (RP 1.70, 95% CI 1.20-2.40) compared to the group with no difficulties in perceived support. In the infant cohort (n=619) and toddler cohort (n=461), the stratified group with the greatest difficulties had higher incidences of problems with depressed mood (RP 9.05, 95% CI 4.36-18.80 and RP 4.63, 95% CI 2.38-9.02, respectively), bonding (RP 1.63, 95% CI 1.29-2.06 and RP 3.19, 95% CI 2.03-5.01, respectively), and sleep quality (RP 8.09, 95% CI 4.62-16.37 and RP 1.72, 95% CI 1.23-2.42, respectively) compared to the group with no difficulties. Conclusions: The classifier, based on a combination of resilience and adaptation to the child’s temperament and perceived support, was able identify psychosocial vulnerable groups in the newborn cohort, the start-up stage of childcare. Psychosocially vulnerable groups were also identified in qualitatively different infant and toddler cohorts, depending on their classifier. The vulnerable group identified in the infant cohort showed particularly high RP for depressed mood and poor sleep quality.


  • Open Access

    Depression and diet‐related distress among Japanese women with gestational diabetes mellitus

    by Kanako Yamada, Masayuki Endo, Kazutomo Ohashi

    Although the association between gestational diabetes mellitus (GDM) and maternal postpartum depression has been reported, the association between these two factors during pregnancy has not been sufficiently examined. We compared pregnant women with and without GDM to clarify the association and examined factors related to depression in pregnant women with GDM. Questionnaires were administered longitudinally to pregnant Japanese women in the third trimester and at 2 and 4 weeks postpartum. One hundred and five and 108 pregnant women with and without GDM, respectively, were included in the study. Of the 105 women with GDM, 20 (19.0%) reported being depressed during pregnancy, which was significantly higher than that among those without GDM (9.3%). Binomial logistic regression analysis revealed that depression was significantly positively associated with diet‐related distress and negatively associated with social support among women with GDM. Diet‐related distress and social support are important factors in managing depression in pregnant women with GDM.


  • High-mobility group box-1 peptide ameliorates bronchopulmonary dysplasia by suppressing inflammation and fibrosis in a mouse model

    by Takeya Hara, Takashi Shimbo, Tatsuo Masuda, Tomomi Kitayama, Makoto Fujii, Morifumi Hanawa, Kazuha Yokota, Masayuki Endo, Takuji Tomimatsu, Tadashi Kimura, et al.


  • Open Access

    Explainable Machine Learning Classification to Identify Vulnerable Groups Among Parenting Mothers: Web-Based Cross-Sectional Questionnaire Study (Preprint)

    by Akiko Hanai, Tetsuo Ishikawa, Shoko Sugao, Makoto Fujii, Kei Hirai, Hiroko Watanabe, Masayo Matsuzaki, Goji Nakamoto, Toshihiro Takeda, Yasuji Kitabatake, et al.

    BACKGROUND One life event that requires extensive resilience and adaptation is parenting. However, resilience and perceived support in child-rearing vary, making the real-world situation unclear, even with postpartum checkups. OBJECTIVE This study aimed to explore the psychosocial status of mothers during the child-rearing period from newborn to toddler, with a classifier based on data on the resilience and adaptation characteristics of mothers with newborns. METHODS A web-based cross-sectional survey was conducted. Mothers with newborns aged approximately 1 month (newborn cohort) were analyzed to construct an explainable machine learning classifier to stratify parenting-related resilience and adaptation characteristics and identify vulnerable populations. Explainable k-means clustering was used because of its high explanatory power and applicability. The classifier was applied to mothers with infants aged 2 months to 1 year (infant cohort) and mothers with toddlers aged >1 year to 2 years (toddler cohort). Psychosocial status, including depressed mood assessed by the Edinburgh Postnatal Depression Scale (EPDS), bonding assessed by the Postpartum Bonding Questionnaire (PBQ), and sleep quality assessed by the Pittsburgh Sleep Quality Index (PSQI) between the classified groups, was compared. RESULTS A total of 1559 participants completed the survey. They were split into 3 cohorts, comprising populations of various characteristics, including parenting difficulties and psychosocial measures. The classifier, which stratified participants into 5 groups, was generated from the self-reported scores of resilience and adaptation in the newborn cohort (n=310). The classifier identified that the group with the greatest difficulties in resilience and adaptation to a child’s temperament and perceived support had higher incidences of problems with depressed mood (relative prevalence [RP] 5.87, 95% CI 2.77-12.45), bonding (RP 5.38, 95% CI 2.53-11.45), and sleep quality (RP 1.70, 95% CI 1.20-2.40) compared to the group with no difficulties in perceived support. In the infant cohort (n=619) and toddler cohort (n=461), the stratified group with the greatest difficulties had higher incidences of problems with depressed mood (RP 9.05, 95% CI 4.36-18.80 and RP 4.63, 95% CI 2.38-9.02, respectively), bonding (RP 1.63, 95% CI 1.29-2.06 and RP 3.19, 95% CI 2.03-5.01, respectively), and sleep quality (RP 8.09, 95% CI 4.62-16.37 and RP 1.72, 95% CI 1.23-2.42, respectively) compared to the group with no difficulties. CONCLUSIONS The classifier, based on a combination of resilience and adaptation to the child’s temperament and perceived support, was able identify psychosocial vulnerable groups in the newborn cohort, the start-up stage of childcare. Psychosocially vulnerable groups were also identified in qualitatively different infant and toddler cohorts, depending on their classifier. The vulnerable group identified in the infant cohort showed particularly high RP for depressed mood and poor sleep quality.

  • Open Access

    The accuracy of contrast-enhanced computed tomography scans to detect postpartum haemorrhage: an observational study

    by Yumi Mitsuyama, Yusuke Katayama, Kazuya Oi, Junya Shimazaki, Kazuya Mimura, Masayuki Endo, Takeshi Shimazu

    Introduction: Postpartum haemorrhage is a major cause of maternal mortality. Although contrast-enhanced computed tomography (CE-CT) is useful to reveal arterial bleeding, its accuracy in postpartum haemorrhage is unclear. The aim of this study was to evaluate the accuracy of CE-CT scanning in detecting postpartum haemorrhage. Methods: This was a retrospective observational study. We included patients with postpartum haemorrhage treated by emergency physicians in collaboration with obstetricians. We calculated the sensitivity, specificity, and positive and negative predictive values for CE-CT scanning to detect arterial bleeding. Results: CE-CT scanning was performed in 52 patients, and 31 patients had extravasation. The sensitivity of CE-CT scanning to detect arterial extravasation was 100% (15/15), specificity was 28.6% (2/7), positive predictive value was 75% (15/20), and negative predictive value was 100% (2/2). Conclusion: We showed the sensitivity of CE-CT scanning to detect arterial extravasation in patients with postpartum haemorrhage to be 100%.


  • Open Access

    Diagnosis, Management, and Therapy of Fetal Ovarian Cysts Detected by Prenatal Ultrasonography: A Report of 36 Cases and Literature Review

    by Takeya Hara, Kazuya Mimura, Masayuki Endo, Makoto Fujii, Tatsuya Matsuyama, Kazunobu Yagi, Yoko Kawanishi, Takuji Tomimatsu, Tadashi Kimura

    Background: Fetal ovarian cysts are the most frequently diagnosed intra-abdominal cysts; however, the evidence for perinatal management remains controversial. Methods: We retrospectively reviewed cases of fetal ovarian cysts diagnosed by prenatal ultrasonography at our institution between January 2010 and January 2020. The following were investigated: gestational age at diagnosis, cyst size, appearance, prenatal ultrasound findings, and postnatal outcomes. Prior to 2018, expectant management was applied in all cases; after 2018, in utero aspiration (IUA) of simple cysts ≥40 mm was performed. Results: We diagnosed 29 and seven simple and complex cysts, respectively. Fourteen patients had simple cysts with a maximum diameter <40 mm, and two of them progressed to complex cysts during follow-up; however, when the diameter was limited to <35 mm, no cases showed progression to complex cyst. Fifteen of the simple cysts were ≥40 mm; three progressed to complex cysts, and two of them were confirmed to be ovarian necrosis. In four patients who underwent IUA, the ovaries could be preserved. Conclusions: IUA is a promising therapy for preserving ovaries with simple cysts ≥40 mm in diameter; however, the indications for fetal surgery and the appropriate timing of intervention require further study.


  • Open Access

    Disparity of Cervical Cancer Risk in Young Japanese Women: Bipolarized Status of HPV Vaccination and Cancer Screening

    by Mariko Taniguchi, Yutaka Ueda, Asami Yagi, Ai Miyoshi, Yusuke Tanaka, Ryoko Minekawa, Masayuki Endo, Takuji Tomimatsu, Kei Hirai, Tomio Nakayama, et al.

    Women born between 1994 and 1999 achieved high vaccination rates for human papillomavirus (HPV); they are now reaching the age of cervical cancer screening programs in Japan. In this study, we aimed to investigate the health awareness of HPV-vaccinated and unvaccinated women and to create tailored leaflets recommending cervical cancer screening for each. Surveys on the cancer screening rates for HPV-vaccinated and unvaccinated women aged 20 and 21 have demonstrated that the rate was significantly higher (p < 0.01) in vaccinated (6.2%) than in unvaccinated women (3.1%). Next, interviews and Internet questionnaires clarified that there was a trend that vaccinated women have a better health consciousness than the unvaccinated ones, and that in unvaccinated women, their willingness to receive cervical cancer screening was significantly enhanced by the fear of developing cancer. Finally, in a prospective study, the increase in the screening rate for both vaccinated and unvaccinated groups after they read tailored leaflets, from 6.4% to 7.4% and from 3.9% to 5.1%, respectively, was not statistically significant compared to the groups provided with a standard reminder letter. Cervical cancer control measures might be enhanced by recommending cervical cancer screening in ways better tailored to HPV vaccination status.


  • Open Access

    Evaluation of a Balloon-Type Vaginal Endoscope Based on Three-Dimensional Printing Technology for Self-Assessment of Pelvic Organ Prolapse

    by Myoungjae Jun, Hieyong Jeong, Masayuki Endo, Michiko Kodama, Yuko Ohno

    Pelvic organ prolapse (POP) can occur if the support tissues or the pelvic floor muscles are weakened and damaged. There is increased probability for POP occurrence after childbirth, menopause, or in overweight women. Because the natural history and progression of POP is still unknown, the approaches used to prevent it have not been clear. POP is an uncomfortable condition that affects one every three women. However, most people feel uncomfortable to discuss it. Herein, we conducted a feasibility evaluation study for self-assessment approaches with a vaginal endoscope based on three-dimensional (3D) printing. The proposed endoscope has two parts: (a) rubber material used to cover it for its intended insertion, to avoid direct contact with the walls of the vagina, and (b) two types of sensors at the tip for measurements. The condition inside the vagina was observed with a camera and depth sensors based on the regulation of the amount of air. Arbitrary temporary prolapses from the testbed’s generator enabled us to perceive the location of the problem and symptoms that were regarded as the early stage. As discussed, the low-cost design of the 3D-printed-based vaginal endoscope provides a self-check capability and allows continuous observations that help prevent POP.


  • Open Access

    Horizontal Cervix as a Novel Sign for Predicting Adhesions on the Posterior Extrauterine Wall in Cases of Placenta Previa

    by Shinya Matsuzaki, Aiko Okada, Masayuki Endo, Yoshikazu Nagase, Satoshi Nakagawa, Kosuke Hiramatsu, Aiko Kakigano, Kazuya Mimura, Tsuyoshi Takiuchi, Takuji Tomimatsu, et al.

    We aimed to identify a magnetic resonance imaging (MRI) feature that can predict posterior extrauterine adhesion (posterior adhesion) antenatally, in patients with placenta previa. We retrospectively reviewed patients with placenta previa who underwent a preoperative MRI examination of placenta accreta spectrum. We categorized the patients into two groups based on whether the cervix was anterior or posterior to a line perpendicular to the anatomical conjugate on the MRI. We projected the perpendicular line toward a straight line through the broad of the back on T2-weighted sagittal MRI images and measured the angle between this line and the line passing through the cervical canal. We analyzed the correlation of the cervical canal angle with the presence of posterior adhesions. Of the 96 patients analyzed, 71 patients had an anteverted cervix and 25 patients had a retroverted cervix. There were 21 posterior adhesions. The adhesion rate was significantly higher in patients with a retroverted cervix than those with an anteverted cervix (8.5% vs. 60%; p = 0.00). The cervical canal angle was ≤10° in 25 patients; of these 17 had adhesions (sensitivity, 81.0%; specificity, 89.3%; area under the curve, 0.887; 95% confidence interval, 0.792–0.981). This finding, labeled “positive horizontal cervix sign,” may be a promising indicator of posterior adhesions in patients with placenta previa.


  • Top Cited Papers
    Open Access

    Preeclampsia: Maternal Systemic Vascular Disorder Caused by Generalized Endothelial Dysfunction Due to Placental Antiangiogenic Factors

    by Takuji Tomimatsu, Kazuya Mimura, Shinya Matsuzaki, Masayuki Endo, Keiichi Kumasawa, Tadashi Kimura

    Preeclampsia, a systemic vascular disorder characterized by new-onset hypertension and proteinuria after 20 weeks of gestation, is the leading cause of maternal and perinatal morbidity and mortality. Maternal endothelial dysfunction caused by placental factors has long been accepted with respect to the pathophysiology of preeclampsia. Over the past decade, increased production of placental antiangiogenic factors has been identified as a placental factor leading to maternal endothelial dysfunction and systemic vascular dysfunction. This review summarizes the recent advances in understanding the molecular mechanisms of endothelial dysfunction caused by placental antiangiogenic factors, and the novel clinical strategies based on these discoveries.