Satoshi Ohira

Shinshu University, Shonai, Nagano, Japan

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Publications (32)75.48 Total impact

  • Placenta 10/2014; 35(10):A11. · 3.12 Impact Factor
  • Placenta 10/2014; 35(10):A8–A9. · 3.12 Impact Factor
  • Satoshi Ohira, Tanri Shiozawa
    Placenta 10/2014; 35(10):A5. · 3.12 Impact Factor
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    ABSTRACT: The invasion of extravillous trophoblasts (EVTs) to the decidua and spiral arteries in early pregnancy is a crucial step for a successful pregnancy; however, its mechanisms are not fully understood. Lipocalin2 (LCN2), a multifunctional secretory protein known as neutrophil gelatinase-associated lipocalin (NGAL), reportedly enhanced invasiveness via the activation of matrix metalloproteinase-9 (MMP-9) in several cancer cells. In this study, the expression and function of LCN2 in early placenta were analyzed. Early placental tissues between 7 and 10 weeks of gestation were obtained from normal pregnant women who underwent elective termination. The expression of LCN2 was examined using immunostaining and RT-PCR. EVTs isolated from these placental tissues and a choriocarcinoma cell line (JAR) were used to investigate the effects of LCN2 on proliferation, invasion potential, and MMP-9 activity under hypoxia using a WST-1 assay, Matrigel invasion assay, and gelatin gel zymography, respectively. The immunohistochemical expression of LCN2 was observed in the cytoplasm of EVTs, cytotrophoblasts and the decidua, but not in syncytiotrophoblasts. The addition of recombinant LCN2 did not affect proliferation, but enhanced the invasiveness (500 ng/mL, p < 0.01) and MMP-9 activity of primary cultured EVTs and JAR in a dose-dependent manner. Silencing LCN2 using shRNA reduced the invasiveness (p < 0.01) and MMP-9 activity of JAR. In addition, the hypoxic condition (2% O2) increased LCN2 expression (p < 0.01), MMP-9 activity, and invasive ability (p < 0.01). LCN2 was involved in the invasiveness of EVTs, especially under hypoxia, via increased MMP-9 activity.
    Placenta 08/2013; · 3.12 Impact Factor
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    ABSTRACT: Placental mesenchymal dysplasia (PMD) is characterized by multiple hypoechoic vesicles which are similar to molar changes in the placenta; however, the process of such morphological changes of PMD during pregnancy has not been fully understood. We performed a review of all PMD cases published in English and identified 49 articles including 110 cases. With regard to the gestational age at which the multicystic pattern was seen, approximately 70% of cases were diagnosed at 13-20 weeks of gestation. Another characteristic feature of PMD is varicose dilation of fetal chorionic vessels. As many as 90% of cases were diagnosed as placenta with dilated fetal chorionic vessels in the third trimester. We also report a case of PMD which was found at 10 weeks of gestation according to ultrasonic molar patterns. Serial observations of the placenta using ultrasound and magnetic resonance imaging revealed that multicystic lesions became smaller after 23 weeks. In contrast, dilated placental vessels on the fetal side became apparent at 38 weeks. The present review highlights that placental vesicular lesions of PMD may precede dilation of fetal chorionic vessels during pregnancy. It also indicates the potential of a gradual reduction in size of PMD's placental vesicular lesions by serial study of placental images.
    Gynecologic and Obstetric Investigation 04/2013; · 1.10 Impact Factor
  • Satoshi Ohira, Tanri Shiozawa
    Nippon rinsho. Japanese journal of clinical medicine 06/2012; 70 Suppl 4:744-8.
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    ABSTRACT: To examine the significance of placental migration and the presence of a placental marginal sinus to predict the eventual route of delivery in low-lying placenta. 49 women with a low-lying placenta after 30 weeks' gestation were studied. The distance between the internal os and leading edge of the placenta was measured weekly using transvaginal ultrasonography until 37 weeks' gestation. The relationship between the rate of placental migration, the presence of a placental marginal sinus and the eventual mode of delivery was investigated. Although the cesarean section rate was 56.3% (9/16) in the 'slow' migration (0-2.0 mm/week) group, no patient (0/33) in the 'fast' (>2.0 mm/week) migration group underwent a cesarean section (p < 0.01). The cesarean section rate was 71.4% (5/7) in patients with a placental marginal sinus, significantly greater than the rate of 9.5% (4/42) in patients without a marginal sinus (p < 0.01). A decreased rate of placental migration until 37 weeks' gestation and the presence of a placental marginal sinus were associated with subsequent cesarean delivery because of antepartum vaginal bleeding. These parameters may be useful for predicting the route of delivery in women with a low-lying placenta.
    Gynecologic and Obstetric Investigation 03/2012; 73(3):217-22. · 1.10 Impact Factor
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    ABSTRACT: Most fetal goitrous hypothyroidisms are reportedly caused by the maternal use of an antithyroid drug or fetal dyshormonogenesis. However, fetal goitrous hypothyroidism due to the transplacental passage of maternal thyroid stimulation-blocking antibody (TSBAb) is extremely rare. A woman at 28 weeks of gestation was found to have a fetal goiter by ultrasonography. Because the maternal serum showed hypothyroidism with an elevated titer of TSBAb, levothyroxine sodium was administered. The patient delivered a male infant, 3,412 g, with a goiter at term. Umbilical blood revealed primary hypothyroidism with increased TSBAb, and the infant was given levothyroxine sodium. After a month, neonatal thyroid function and TSBAb levels became normal. Attention should be paid to possible fetal hypothyroidism when a fetal goiter is observed to avoid impaired mental development of the neonate.
    Fetal Diagnosis and Therapy 09/2010; 28(4):220-4. · 1.90 Impact Factor
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    ABSTRACT: Expression levels of cytochrome P450 (CYP) 3A4, CYP3A5 and CYP3A7 mRNAs in placentas and fetal membranes, which were split into amnion and chorion leave attached decidua (chorion/decidua), obtained from pregnant women with normal delivery (5 subjects) and Caesarean section (15 subjects) were determined. These CYP3A mRNAs were also expressed in amnion and chorion/decidua together with placenta, although the expression level of these mRNAs was strikingly different between subjects. The expression level of the CYP3A4 mRNA in the placenta was about 2-fold higher than those in amnion and chorion/decidua. On the other hand, the expression levels of CYP3A5 and CYP3A7 mRNAs were highest in chorion/decidua. The immunologically related protein(s) with CYP3A7 was detected in all tissues examined. Testosterone 6beta-hydroxylase activity in homogenate of human placenta, amnion and chorion/decidua were 26.6, 3.7 and 4.6 pmol/h/mg protein, respectively. These results suggest that CYP3As in fetal membranes have the metabolic function to protect the fetus from exposure to drugs.
    Biological & Pharmaceutical Bulletin 02/2010; 33(2):249-54. · 1.85 Impact Factor
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    ABSTRACT: Changes in the expression of E-cadherin have been reported to be important in the tumorigenesis and progression of epithelial ovarian carcinoma. To further examine the mechanisms regulating E-cadherin expression in ovarian tumorigenesis, we investigated the immunohistochemical expression of transcriptional repressors for E-cadherin, such as Snail, Slug, SIP1, and Twist, in the ovarian surface epithelium (OSE) and 95 cases of epithelial ovarian tumors. OSE cells were negative for SIP1 and Slug, whereas weak expression of Snail and Twist was observed in 8 (73%) and 3 (27%) cases, respectively. Of 95 ovarian tumors, the expression of Snail, Slug, SIP1, and Twist increased stepwise in benign, borderline, and malignant tumors. Among them, the expression of Snail showed significantly inverse correlation with that of E-cadherin. Regarding the FIGO stage classification, the expressions of Snail and Twist were significantly increased in advanced cases. The prognosis of ovarian carcinoma patients positive for Snail expression was poorer than that of negative patients. Our results indicate that the expression of E-cadherin transcriptional repressors increased with malignancy in ovarian epithelial neoplasms and that the expression of E-cadherin and its negative regulators is altered during ovarian cancer development and peritoneal dissemination.
    Medical Molecular Morphology 07/2009; 42(2):82-91. · 1.17 Impact Factor
  • Medical Molecular Morphology 06/2009; · 1.17 Impact Factor
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    ABSTRACT: Prolongation of pregnancy in cases of fetal membrane prolapse into the vagina during the second trimester is difficult using conservative therapy. After pushing the membranes back into the cervix, emergency cervical cerclage may be advantageous in improving the neonatal outcome. We have been managing membrane repositioning and emergency cervical cerclage with a technique using a rubber balloon device (known as a 'mini metreu' in Japan), and we examined the efficacy of this technique in five cases. Our management was as follows: initially, the full bladder technique was attempted under general anesthesia. If this was not effective, amnioreduction was performed by transabdominal amniocentesis. After the membrane repositioning using a mini metreu, double suture cervical cerclage (McDonald method + Shirodkar method) was performed. The diameter of the bulging prolapsed membranes ranged from 30-84 mm, with a mean of 52 mm. Cerclage was successfully performed in all of the five cases. Prolongation of the pregnancy period was from 22-107 days (average; 77.6 +/- 28.9 days). In cases 1-4, healthy newborns were delivered, but in case 5 sudden intrauterine fetal death due to umbilical cord complications occurred at 24 weeks of gestation. It appears that long-term prolongation of pregnancy is possible, when performing membrane repositioning using the mini metreu and emergency cervical cerclage for fetal membrane prolapse into the vagina.
    Journal of Obstetrics and Gynaecology Research 01/2009; 34(6):935-40. · 0.84 Impact Factor
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    ABSTRACT: The definitive version is available at
    Journal of Obstetrics and Gynaecology Research 01/2008; · 0.84 Impact Factor
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    ABSTRACT: Semaphorins (SEMAs) compete with vascular endothelial growth factor (VEGF) for receptor neuropilin 1 (NP1) and 2 (NP2) and suppress angiogenesis. To clarify the involvement of SEMA and VEGF in the development and progression of ovarian carcinoma, we analyzed the immunohistochemical expression of SEMA, VEGF, NP1, and NP2 in 105 epithelial ovarian tumors. In addition, loss of heterozygosity at SEMA gene loci was examined. Strong expression of SEMA was found in 48% of benign, 33% of borderline tumors, and 13% of carcinomas (P < .05). Positivity for SEMA was significantly decreased in stage IV carcinomas and the expression of SEMA was significantly lower in peritoneal metastases than in primary lesions. Expression of SEMA showed a weak inverse correlation with microvessel density, but the correlation was not statistically significant. Loss of heterozygosity at SEMA3B or SEMA3F was demonstrated in none of the benign tumors, 8% of borderline tumors, and 29% of carcinomas. Expression of NP1 and NP2 was significantly higher in carcinomas than in benign tumors (P < .0001 and .0002, respectively). Patients with ovarian carcinoma with a high VEGF/SEMA ratio showed poorer survival than those with a low VEGF/SEMA ratio (P = .005). Decreased expression of SEMA and increased expression of NP1 and NP2 are characteristics of ovarian carcinomas, and loss of SEMA expression may play an important role in ovarian carcinoma progression. A high VEGF/SEMA ratio has adverse prognostic significance in patients with ovarian carcinoma.
    Human Pathlogy 11/2006; 37(11):1414-25. · 2.84 Impact Factor
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    ABSTRACT: Although the effectiveness of magnetic resonance imaging (MRI) in depicting cervical carcinoma has been reported, whether MRI can detect early-stage or stage IB "occult"-type cervical carcinoma remained undetermined. We examined the correlation between MRI and pathologic findings in 38 stage I (IB 28 cases, IA 10 cases) cervical carcinoma patients, with special reference to the influence of desmoplastic stromal reaction around the tumor. The results demonstrated that the tumor was detected by MRI in none of stage IA patients but in 21 (75%) stage IB patients. The image was clearly demonstrated in 15 of 18 (83%) tumors of more than 2 cm in diameter and in 6 of 10 (60%) tumors of 2 cm or less. The tumor image was evident in 21 of 22 (95%) tumors with prominent (>200 micron) stromal reaction but in none of 6 tumors with minimal (</= 200 micron) stromal reaction. These findings suggest that MRI is not useful for the detection of stage IA tumors. In stage IB tumors, however, the stromal reaction rather than the size of the tumor may influence the tumor's image in MRI.
    International Journal of Gynecological Cancer 01/2006; 16(2):610-4. · 1.94 Impact Factor
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    ABSTRACT: E-cadherin and catenins play key roles in cell adhesion and motility. Little is known about the changes in expression of these molecules in the progression of ovarian carcinomas. In the present study, the immunohistochemical expression of E-cadherin and alpha-, beta-, and gamma-catenins was examined in 77 cases of ovarian carcinoma. In addition, the expression of these molecules was evaluated in 26 matched pairs of primary and metastatic lesions of advanced ovarian carcinomas. Of the 77 primary lesions, positive staining for E-cadherin and alpha-, beta-, and gamma-catenin was observed in 75 (97%), 63 (82%), 71 (92%) and 57 (74%) cases, respectively. Positivity for E-cadherin and alpha-, beta-, and gamma-catenin was significantly decreased in stage III and IV tumors compared with stage I and II tumors, suggesting that expression of the cadherin-catenin complex is reduced with the advancing stages of a tumor. Interestingly, expression of E-cadherin and alpha-, beta-, and gamma-catenin in the lesions of peritoneal dissemination was significantly increased compared with the primary lesions. These findings suggest that expression of the cadherin-catenin complex changes markedly and that reexpression may occur during the peritoneal dissemination of ovarian carcinoma cells.
    Human Pathlogy 01/2005; 35(12):1469-76. · 2.84 Impact Factor
  • Human Pathlogy 12/2004; · 2.84 Impact Factor
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    ABSTRACT: Ovarian tumors associated with hypercalcemia due to ectopic secretion of parathyroid hormone (PTH) are extremely rare. A 33-year-old woman presented with a pelvic mass and profound hypercalcemia accompanied by an elevated serum level of PTH. Laparotomy demonstrated a left ovarian tumor that on histological examination was a neuroendocrine carcinoma of non-small cell type admixed with a component of endometrioid adenocarcinoma. After left salpingo-oophorectomy, the serum calcium and PTH levels normalized. The cells of the neuroendocrine carcinoma were positive for neuron-specific enolase, synaptophysin, chromogranin A, and PTH. Hypercalcemia and elevated serum PTH levels recurred during tumor relapse, and the patient died of disease 6 months postoperatively. This is the eleventh case of neuroendocrine carcinoma of non-small cell type associated with surface epithelial neoplasm of the ovary, and the first such tumor to be associated with hypercalcemia.
    International Journal of Gynecological Pathology 11/2004; 23(4):393-7. · 1.41 Impact Factor
  • International Journal of Gynecological Pathology 10/2004; · 1.41 Impact Factor
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    ABSTRACT: BRCA1 is a putative tumour suppressor gene responsible for a hereditary ovarian cancer syndrome. To clarify the possible involvement of BRCA1 in the development of sporadic ovarian neoplasms, this study analysed the immunohistochemical expression of BRCA1 protein in normal ovarian surface epithelium and 119 epithelial ovarian tumours (19 benign, 24 borderline, and 76 malignant tumours). Loss of heterozygosity (LOH) of BRCA1 was examined using three microsatellite markers to analyse the relationship between BRCA1 expression and alterations of the BRCA1 gene. Methylation of the BRCA1 promoter was also analysed by methylation-specific PCR. In ovarian carcinomas showing heterogeneous expression of BRCA1 protein in the same tumour, LOH and methylation status were analysed using microdissection techniques. Finally, the relationship of BRCA1 expression or its genetic alteration to clinicopathological parameters and patient survival was analysed. Ovarian surface epithelial cells expressed BRCA1 protein. Decreased expression of BRCA1 was found in 16% of benign tumours, 38% of borderline tumours, and 72% of carcinomas. LOH of BRCA1 was demonstrated in no benign tumours, 15% of borderline tumours, and 66% of carcinomas. Methylation of BRCA1 was not detected in benign or borderline tumours, but was present in 31% of carcinomas. Reduced expression of BRCA1 correlated with the presence of gene methylation. The frequency of BRCA1 methylation and LOH was higher in serous carcinomas than in other types. In one of the three serous carcinomas that showed heterogeneous expression of BRCA1, BRCA1-positive borderline-like tumour cells were LOH-positive and methylation-negative, whereas adjacent BRCA1-negative carcinoma cells were LOH-positive and methylation-positive. The prognosis of carcinoma patients did not correlate with BRCA1 expression or genetic status. These findings suggest that reduced expression of BRCA1 protein along with genetic and epigenetic changes of the BRCA1 gene play an important role in the development of sporadic ovarian carcinomas, particularly those of serous histology.
    The Journal of Pathology 03/2004; 202(2):215-23. · 7.59 Impact Factor

Publication Stats

732 Citations
75.48 Total Impact Points


  • 2000–2014
    • Shinshu University
      • • Department of Obstetrics and Gynecology
      • • Department of Family and Child Nursing and Midwifery
      Shonai, Nagano, Japan