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Placenta | 1998

Telomerase activity in human chorionic villi and placenta determined by TRAP and in situ TRAP assay

Toshihiko Izutsu; Tomohiko Kudo; Tamotsu Sato; Iwao Nishiya; Kazuma Ohyashiki; Mitsuko Mori; Kan-ichi Nakagawara

Telomerase activity (TA) was analysed in human chorionic villi and placenta in normal and abnormal pregnancy using the telomeric repeat amplification protocol (TRAP) and in situ TRAP assay. Twenty chorionic villi specimens and 25 placenta specimens from normal pregnancies were examined as well as placenta specimens from 10 cases of intrauterine growth retardation (IUGR; nine asymmetric and one symmetric). TA was detected in 18 of the 20 (90 per cent) chorionic villi specimens and in 18 of the 25 (72 per cent) placenta specimens from normal pregnancy. However, no or only weak TA was exhibited in the placenta specimens of the nine asymmetric IUGR cases. In situ TRAP assay detected TA in trophoblastic cells from normal pregnancy, but not in trophoblastic cells from cases of asymmetric IUGR.


Journal of Obstetrics and Gynaecology Research | 2001

Nitric Oxide Mediates Inhibitory Effect of Interleukin‐1β on Estrogen Production in Human Granulosa‐Luteal Cells

Hisako Tobai; Iwao Nishiya

Objective: To investigate the effect of IL‐1β on NO production and steroidogenesis in human granulosa‐luteal cells obtained from women undergoing in vitro fertilization procedures.


Obstetrics & Gynecology | 1999

Telomerase and proliferative activity in placenta from women with and without fetal growth restriction

Toshihiko Izutsu; Tomohiko Kudo; Tamotsu Sato; Iwao Nishiya; Kazuma Ohyashiki; Kanichi Nakagawara

OBJECTIVE To analyze telomerase and proliferative activity in placenta from women with and without fetal growth restriction (FGR). METHODS Telomerase activity was analyzed in 30 first-trimester chorionic villi specimens (group A) and in 28 second- and third-trimester placenta specimens (group B) from women without FGR. Telomerase activity also was analyzed in 11 placenta specimens from women with asymmetric FGR (group C). The proliferative activity of these 69 specimens was assessed by immunohistochemical staining, using the MIB-1 monoclonal antibody. RESULTS Telomerase activity was detected in 28 (93.3%) of 30 chorionic villi specimens and in 18 (64.3%) of 28 placenta specimens without FGR. In contrast, no telomerase activity was exhibited in the placenta specimens from any of the 11 women with asymmetric FGR by telomeric repeat amplification protocol assay. Telomerase activity also was detected by in situ telomeric repeat amplification protocol assay in trophoblastic cells from women without FGR but not in trophoblastic cells from women with asymmetric FGR. Thus, telomerase activity was detected significantly more often in groups A and B than in group C (P < .01). The rate of proliferative activity, evident as positive MIB-1 staining in trophoblastic cells, in groups A and B (28.1+/-1.7% and 7.0 +/-2.9%, respectively) was significantly higher than that in group C (1.9+/-0.6%; P < .01). CONCLUSION Telomerase and proliferative activity were minimal in placenta from women with asymmetrical FGR, suggesting placental senescence with asymmetrical FGR.


Placenta | 1989

Electron microscopic study on early decidualization of the endometrium of pregnant mice, with special reference to gap junctions

Hiroshi Ono; Chizuka Ide; Iwao Nishiya

Cytological changes in mouse decidual cells during the early stages from 4.5th to 11th day of pregnancy were examined by electron microscopy with special reference to gap junctions. The most noticeable feature of decidual cells was that there was an abundance of various-shaped gap junctions such as flat, undulated, omega-shaped, and annular-shaped gap junctions. Serial sectioning revealed that annular-shaped gap junctions were separated from the decidual cell plasma membrane. Intramembranous particles (IMPs) of the gap junctions as seen by freeze-fracture displayed a well-packed arrangement and a homogeneous size. Degenerative changes first appeared in decidual cells directly contiguous with trophoblasts on the 7th day, and spread to the deeper area as clearly seen on the 8th day. Along with degeneration of decidual cells, annular-shaped gap junctions were enfolded and gradually degraded by lysosomes. IMPs of such degenerative gap junctions were irregularly arranged and heterogenous in size. The decidual tissue became thin with elongated decidual cells as the placental disc grew on the 10th day. Extremely long undulated gap junctions were present in decidual cells, and a small number of annular-shaped gap junctions were also found in the cytoplasm. The presence of abundant gap junctions as demonstrated in the present study suggests that decidual cells will be able to develop as well as to function synchronously. In addition, it is suggested that redundant gap junctions become annular-shaped to be finally degraded by lysosomes.


Cell Biology International Reports | 1991

Glucocorticoid-induced G1 arrest and the release effect of epidermal growth factor on the human salivary gland adenocarcinoma cell☆

Setsuko Hatakeyama; Atsumi Suzuki; Noboru Yoshizumi; Masahiko Sato; Iwao Nishiya

Dexamethasone (1 microM) decreased the distribution of cells in S phase (about 75%) and increased that of G1 cells (1.1-fold) in the DNA histogram of human submandibular salivary gland adenocarcinoma cells (HSG) reversibly. In synchronized cells at G1 phase, glucocorticoid delayed the initiation of DNA synthesis by about 3-4 h. The conditioned medium (50%) or exogenous human epidermal growth factor (EGF, 10 ng/ml) significantly nullified these effects by glucocorticoids. These results suggested that glucocorticoids arrested the cells at G1 phase, which implied the inhibition of production of some progressive factor, probably EGF, in the cell cycle of HSG.


Cancer Genetics and Cytogenetics | 1995

Numerical and structural chromosome abnormalities in an ovarian fibrothecoma

Toshihiko Izutsu; Tomohiko Kudo; Fumiharu Miura; Iwao Nishiya

Cytogenetic analysis of a fibrothecoma of ovary revealed numerical and structural chromosome abnormalities, i.e., 44,XX, dup(1)(p13p31),del(3)(p14) add (10p), -16, -22. This is the first report of numerical and structural abnormalities in a fibrothecoma of the ovary.


Journal of Obstetrics and Gynaecology Research | 1996

Comparative Cytogenetic Studies of Benign, Borderline, and Malignant Epithelial Ovarian Tumors

Toshihiko Izutsu; Tomohiko Kudo; Tadahiro Shoji; Iwao Nishiya

Comparative cytogenetic studies were performed in 40 cases of untreated epithelial ovarian tumors. Of these 40 tumors, 13 were classified as benign, 3 as borderline, and 24 as malignant, according to the WHO classification for ovarian tumors. Of 13 benign ovarian tumors, 4 (30.8%) showed chromosomal abnormalities. Of 4 ovarian tumors, 3 (75%) had single chromosomal abnormalities, and the remaining tumor (25%) retained multiple chromosomal abnormalities.


Archive | 1991

Effect of Antithrombin III Concentrate for DIC in Obstetrics and Gynecology

Hiroshi Suzuki; Mayumi Kasai; Ken Satoh; Hajime Iida; Hiroki Suzuki; Iwao Nishiya

Obstetrical disseminated intravascular coagulation (DIC) is frequently acute and sometimes life threatening. However, early diagnosis and prompt treatment often save lives. We have shown in patients with gestosis that changes in vasoactive substances such as prostaglandin and prostanoid are associated with progression of the disease that induces chronic DIC [1–3]. On the other hand, DIC complicating gynecological malignant tumors are mostly seen at the terminal stage of the disease, and, therefore, active treatment for DIC has been rarely performed. However, recent advances in the anti-cancer therapy and radiotherapy for gynecological malignant tumors have prolonged the life of some patients. During chemotherapy with anti-cancer drugs, DIC sometimes develops, and active treatment for DIC is often required. In this study, we administered an antithrombin III concentrate (AT-III) to 7 patients with obstetric DIC and 10 of 15 patients treated for gynecological malignant tumors who had DIC or were expected to develop DIC. To evaluate the usefulness of this drug, the AT-III activity and various effects, especially on prostanoid, were studied.


Acta Histochemica Et Cytochemica | 1987

IMMUNOHISTOCHEMICAL STUDIES ON TUMOR ANTIGEN-4 IN SQUAMOUS CELL CARCINOMA OF UTERINE CERVIX

Morimasa Matsuta; Teruo Kagabu; Iwao Nishiya


Cytometry | 1991

Flow cytometric and biochemical analysis of dose-dependent effects of sodium butyrate on human endometrial adenocarcinoma cells.

Satoshi Saito; Harry A. Crissman; Nishijima M; Teruo Kagabu; Iwao Nishiya

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Teruo Kagabu

Iwate Medical University

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Satoshi Saito

Iwate Medical University

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Tomohiko Kudo

Iwate Medical University

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Ken Sato

Iwate Medical University

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Nishijima M

Iwate Medical University

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