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Dive into the research topics where Hideya Kodama is active.

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Featured researches published by Hideya Kodama.


Developmental Biology | 2003

Survivin acts as an antiapoptotic factor during the development of mouse preimplantation embryos.

Kazuhiro Kawamura; Naoki Sato; Jun Fukuda; Hideya Kodama; Jin Kumagai; Hideo Tanikawa; Yasushi Shimizu; Toshinobu Tanaka

Apoptosis is an essential physiologic process used in almost all tissues to remove damaged or superfluous cells. However, the early embryos are unique because no cell death is found up to the blastocyst stage during normal development. Survivin, a member of the IAP family, is capable of binding to caspases to modulate their functions. Here, we investigated the expression of survivin, and its role in preventing apoptosis in mouse preimplantation embryos. Transcripts for survivin and a splice variant lacking exon 2 were detected from unfertilized oocytes up to hatched blastocyst stage. At the protein level, survivin was also detected at all stages of early embryos. The antisense approach was used to demonstrate the role of survivin on embryo development. Development of early embryos treated with antisense survivin oligonucleotides was arrested at the morula or early blastocyst stage with disruption of tubulin formation and abnormal nuclei, associated with apoptosis. The effect of the antisense was enhanced by cotreatment with an apoptosis-inducing reagent, staurosporine. In contrast, apoptosis induced by the antisense treatment was inhibited by caspase-3 and -9 inhibitors. These results indicate that survivin is an essential antiapoptotic gene expressed in preimplantation embryos and could protect the embryos from apoptosis by inhibiting an apoptotic pathway involving caspases.


Fertility and Sterility | 1996

Status of the coagulation and fibrinolytic systems in ovarian hyperstimulation syndrome

Hideya Kodama; Jun Fukuda; Hiroko Karube; Toshihiko Matsui; Yasushi Shimizu; Toshinobu Tanaka

OBJECTIVE To elucidate characteristic changes of plasma hemostatic markers in ovarian hyperstimulation syndrome (OHSS) cycles. DESIGN Prospective study. SETTING The IVF-ET program of the Department of Obstetrics and Gynecology, The University of Akita, School of Medicine. PATIENTS Forty cycles of 40 IVF patients, including 12 cycles in which a severe form of OHSS occurred. INTERVENTIONS Blood samples were taken during IVF treatment to determine the levels of blood markers that reflect activation of the coagulation and fibrinolytic systems. MAIN OUTCOME MEASURES Thrombin-antithrombin III complexes, plasmin-alpha 2 antiplasmin complexes, and other hemostatic markers related to the coagulation and fibrinolytic system activation. RESULTS In the OHSS cycles, the levels of thrombin-antithrombin III and plasmin-alpha 2 antiplasmin complexes in the plasma began to rise within a few days after hCG administration and demonstrated significantly higher levels during the midluteal phase. In OHSS cycles with pregnancy, elevation of these markers continued for > or = 3 weeks after the onset of disease. There were some characteristic changes in OHSS cycles in other hemostatic markers, such as a decrease in the levels of antithrombin III and prekallikrein and shortened activated partial thromboplastin time. CONCLUSION These data demonstrate the status of the coagulation and fibrinolytic systems in OHSS cycles and provide insight into the mechanism of activation in the hemostatic system.


Molecular and Cellular Endocrinology | 2003

The role of leptin during the development of mouse preimplantation embryos

Kazuhiro Kawamura; Naoki Sato; Jun Fukuda; Hideya Kodama; Jin Kumagai; Hideo Tanikawa; Masanori Murata; Toshinobu Tanaka

Leptin is known to regulate diverse reproductive functions, and recent studies have implicated involvement of leptin in the early mouse embryo development. The aim of the present study was to investigate the expression of leptin and its functional receptor (OB-Rb) in mouse oocyte and preimplantation embryo, and to examine whether leptin influenced the early embryo development. Leptin mRNA was detected in blastocyst and hatched blastocyst, and OB-Rb mRNA was detected in oocytes, 1-cell, 2-cell, morula, blastocyst and hatched blastocyst. As for the origin of leptin, leptin mRNA was identified in both the oviduct and uterus of the pregnant mouse. Furthermore, in the pregnant mouse, the levels of leptin in uterine fluid were higher than those in the non-pregnant mouse. Supplementation of culture medium with leptin promotes the development of preimplantation embryos from 2-cell stage to the blastocysts, fully expanded blastocysts and hatched blastocysts. Leptin significantly increased the total cell number of blastocysts, and the effect was preferentially observed in the trophectoderm. These findings raise the possibility that leptin regulates the development of mouse preimplantation embryo through a paracrine pathway.


Fertility and Sterility | 1995

Characteristics of blood hemostatic markers in a patient with ovarian hyperstimulation syndrome who actually developed thromboembolism.

Hideya Kodama; Jun Fukuda; Hiroko Karube; Toshihiko Matsui; Yasushi Shimizu; Toshinobu Tanaka

OBJECTIVE To investigate whether a patient with ovarian hyperstimulation syndrome (OHSS) demonstrated characteristic changes in the blood hemostatic markers before she developed thromboembolism. DESIGN Patients with OHSS had blood drawn to determine hemostatic markers and related factors. PATIENTS Twenty-three OHSS patients, including a case complicated with thromboembolism. SETTING The IVF-ET program of the Department of Obstetrics and Gynecology, The University of Akita, School of Medicine. MAIN OUTCOME MEASURES Blood hemostatic markers and related factors. RESULTS The patient with thromboembolism demonstrated marked leukocytosis and higher levels of activation in the blood markers related to fibrinolytic system, such as alpha 2 plasmin inhibitor, plasmin-alpha 2 antiplasmin complexes, and D-dimers, before the onset of this episode. CONCLUSION Marked leukocytosis and higher levels of activation of the fibrinolytic system may be the signs of imminent thromboembolism in OHSS patients.


Fertility and Sterility | 1996

Benefit of in vitro fertilization treatment for endometriosis-associated infertility

Hideya Kodama; Jun Fukuda; Hiroko Karube; Toshihiko Matsui; Yasushi Shimizu; Toshinobu Tanaka

OBJECTIVE To evaluate the effectiveness of IVF treatment in endometriosis-associated infertility. DESIGN Nonrandom retrospective study. SETTING Department of Gynecology and Obstetrics, Akita University School of Medicine. MAIN OUTCOME MEASURE(S) Cumulative pregnancy rate. PATIENT(S) One hundred eighteen infertile patients in whom diagnosis of endometriosis was established by laparoscopic examination. INTERVENTION(S) The prognoses of 60 patients (IVF group) who started IVF treatment within 6 months after laparoscopy were compared with those of 58 patients who were managed expectantly without IVF treatment during the same period. RESULT(S) The cumulative conception rates at 36 months after laparoscopy were 62% in the IVF group and 43% in the control group, and the difference was not significant (a log-rank test). For patients > or = 32 years of age, the conception rates were significantly higher in the IVF group (59% versus 29%). A relatively large but nonsignificant difference in the conception rate between the two groups was observed in patients with endometriosis at stages III or IV (52% versus 27%). CONCLUSION(S) In vitro fertilization treatment provides better prognosis in patients > or = 32 years of age and is recommended for such patients. The benefits of treatment appear to be greater in patients with more advanced stages of endometriosis.


American Journal of Obstetrics and Gynecology | 1998

The role of cytokines in cervical ripening: correlations between the concentrations of cytokines and hyaluronic acid in cervical mucus and the induction of hyaluronic acid production by inflammatory cytokines by human cervical fibroblasts.

Masaki Ogawa; Hideto Hirano; Hiromitsu Tsubaki; Hideya Kodama; Toshinobu Tanaka

OBJECTIVES The purpose of our study was (1) to explain the relationship between levels of inflammatory cytokines and levels of hyaluronic acid in cervical mucus of pregnant women and (2) to investigate whether cytokines promote hyaluronic acid production by human cervical fibroblasts in vitro. STUDY DESIGN The concentration of hyaluronic acid, interleukin-1beta, and interleukin-8 were measured in cervical mucus of pregnant women, and hyaluronic acid production by cytokine-treated (interleukin-1beta and interleukin-8) cultured fibroblasts was measured. RESULTS Hyaluronic acid concentrations in the mucus of pregnant women with threatened premature labor were higher than in mucus of normal pregnant women (P < .05). Correlations were found between hyaluronic acid concentrations and interleukin-1beta (P = .018) and interleukin-8 (P = .003) concentrations in cervical mucus. Cytokines (especially interleukin-8) stimulated hyaluronic acid production by cultured cervical fibroblasts. CONCLUSION Cytokines induce hyaluronic acid production by human cervical fibroblasts, which may promote cervical ripening.


American Journal of Obstetrics and Gynecology | 1992

Effects of danazol at the immunologic level in patients with adenomyosis, with special reference to autoantibodies: A multi-center cooperative study

Hirotaka Ota; Masahiro Maki; Yoshihiro Shidara; Hideya Kodama; Hiromu Takahashi; Masaaki Hayakawa; Ryoju Fujimori; Toru Kushima; Koichi Ohtomo

OBJECTIVE We attempted to evaluate the effects of danazol on autoantibodies, in particular, to phospholipids, and on the immune system in patients with adenomyosis. STUDY DESIGN Forty-two patients with adenomyosis who had high titers of autoantibodies were randomly chosen, and they received 400 mg/day of danazol for 4 months (n = 22) or underwent hysterectomy (n = 20). RESULTS Among the six autoantibodies we investigated, the incidence of antiphosphatidylinositol immunoglobulin G was the highest (42.9%), followed by antiphosphatidylglycerol immunoglobulin G (38.1%). The autoantibody titers decreased with time and were comparable to the control values 16 weeks after treatment in both groups. Total serum levels of immunoglobulin G and M were high before treatment, but immunoglobulin M levels decreased significantly in week 8 during treatment with danazol, whereas C4 levels increased and C3 levels decreased with danazol. CONCLUSION Danazol has an inhibitory effect on the autoimmunologic response associated with adenomyosis.


Biology of Reproduction | 2005

Survivin Contributes to the Anti-Apoptotic Activities of Transforming Growth Factor alpha in Mouse Blastocysts Through Phosphatidylinositol 3′-Kinase Pathway

Kazuhiro Kawamura; Jun Fukuda; Yasushi Shimizu; Hideya Kodama; Toshinobu Tanaka

Abstract Transforming growth factor alpha (TGFA) is produced by epithelial cells in the oviducts and uteri and has the potential to act as an anti-apoptotic factor on preimplantation embryos expressing its receptor. Previously, we demonstrated that survivin (also known as BIRC5), an anti-apoptotic gene expressed in mouse preimplantation embryos, protects embryos from apoptosis. In this study, we investigated the role of survivin on TGFA-mediated inhibition of apoptosis in mouse blastocysts. Under the suboptimal conditions produced by single embryo culture, blastocysts showed an increase of apoptosis that correlated with a decrease of survivin expression. TGFA treatment significantly decreased apoptosis and increased the levels of survivin mRNA in a dose-dependent manner in blastocyst, and conversely, these activities were neutralized by an anti-TGFA antibody. Antibody treatment alone exerted little effect on either the occurrence of apoptosis or the levels of survivin mRNA. Upregulation of survivin expression by TGFA treatment was insignificant before the blastocyst stage. Using an antisense approach, we examined whether upregulation of survivin is responsible for the anti-apoptotic effect of TGFA in blastocysts. Apoptosis was inhibited by TGFA treatment in blastocysts, but the effect was abrogated by cotreatment with antisense oligonucleotides directed against survivin. These data suggest that survivin contributes to the anti-apoptotic activities of TGFA in blastocysts. We also found that the upregulation of survivin expression was mediated by activation of the phosphatidylinositol 3-kinase (PI3K) signaling pathway. Thus, TGFA inhibits apoptosis in mouse blastocysts through upregulation of survivin expression via the PI3K pathway.


Fertility and Sterility | 1999

Spontaneous conception after the birth of infants conceived through in vitro fertilization treatment

Yasushi Shimizu; Hideya Kodama; Jun Fukuda; Masanori Murata; Jin Kumagai; Toshinobu Tanaka

OBJECTIVE To investigate the incidence of spontaneous conception after the birth of infants conceived through IVF in couples with subfertility caused by endometriosis, a mild male factor, or unexplained factors, and to identify clinical conditions related to the occurrence of spontaneous conception. DESIGN Retrospective analysis. SETTING Department of Obstetrics and Gynecology, Akita University School of Medicine, Akita, Japan. PATIENT(S) One hundred forty-two women who conceived through IVF and 25 of the 142 women who subsequently conceived spontaneously. INTERVENTION(S) Patient characteristics and IVF data were obtained from hospital records, and follow-up data were collected through telephone interviews. MAIN OUTCOME MEASURE(S) Cumulative conception rate. RESULT(S) The cumulative conception rate at 60 months after the delivery of infants conceived through IVF was 18%, with most conceptions occurring within 2 years of delivery. Proportional hazard analysis indicated that patient age was the most important clinical variable related to the occurrence of spontaneous conception. CONCLUSION(S) This study provides information that will be useful in counseling subfertile couples who have conceived through the use of IVF.


American Journal of Obstetrics and Gynecology | 1996

Decreased very-low-density lipoprotein and low-density lipoprotein receptor messenger ribonucleic acid expression in placentas from preeclamptic pregnancies

Masanori Murata; Hideya Kodama; Kaoru Goto; Hideto Hirano; Toshinobu Tanaka

OBJECTIVE Our purpose was to investigate the levels of very-low-density lipoprotein and low-density lipoprotein receptor messenger ribonucleic acid expression in placentas obtained from normal pregnant women at various gestational stages and from patients with preeclampsia. STUDY DESIGN The relative level of expression of very-low-density lipoprotein and low-density lipoprotein receptor messenger ribonucleic acid in each sample was determined by Northern blot analysis as a ratio of the intensity to that of glyceraldehyde-3-phosphate dehydrogenase messenger ribonucleic acid. RESULTS The expression of very-low-density lipoprotein receptor messenger ribonucleic acid increased significantly (p < 0.05) from both the first (n = 9) and second (n = 8) trimesters to the third (n = 11) trimester. Similarly, the expression of low-density lipoprotein receptor messenger ribonucleic acid increased significantly (p < 0.05) from the first to the third trimester. The expression of both very-low-density lipoprotein and low-density lipoprotein receptor messenger ribonucleic acids in third-trimester placentas from preeclamptic pregnancies (n = 13) was significantly lower than that in normal pregnancies in the third trimester. CONCLUSION These results demonstrate the expression of very-low-density lipoprotein and low-density lipoprotein receptor messenger ribonucleic acids in the human placenta, both of which increase at late gestational stages, and the decreased expression in cases of preeclampsia. Abnormal fetomaternal lipid metabolism resulting from low expression of these receptors in the placenta may be involved in the pathogenesis of preeclampsia.

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Kazuhiro Kawamura

St. Marianna University School of Medicine

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