Masami Kawabata
Osaka City University
Network
Latest external collaboration on country level. Dive into details by clicking on the dots.
Publication
Featured researches published by Masami Kawabata.
Journal of Ultrasound in Medicine | 1998
Hiroshi Tsuda; Masami Kawabata; Osamu Nakamoto; Kumio Yamamoto
This study was conducted to examine the correlation between uterine vascularity and natural history of uterine leiomyoma. Seventy women with leiomyoma participated in this study. Measurements of uterine and leiomyoma volume, as well as blood flow characteristics of the main uterine artery and leiomyoma arteries, were made every 3 months for 1 year. Leiomyoma arteries could be detected in 52 (51.5%) of 101 leiomyomas. Leiomyoma volume increased in 24 (46.2%) of 52 leiomyomas with leiomyoma artery. However, the leiomyoma volume increased in only three (6.1%) of 49 leiomyomas without leiomyoma artery. No difference was found between the pulsatility index of the leiomyoma artery in the group with increased size and in the group with stable size. This study shows the vascularity of leiomyoma to be useful as a predictor of leiomyoma growth.
American Journal of Obstetrics and Gynecology | 1995
Hiroshi Tsuda; Masami Kawabata; Kazume Kawabata; Kumio Yamamoto; Atsuo Hidaka; Naohiko Umesake; Sachio Ogita
Abstract The findings of this study suggest that the mean endometrial thickness and the cutoff thickness for detection of endometrial cancer in Occidental and Oriental postmenopausal women may differ.
Gynecologic and Obstetric Investigation | 1995
Naohiko Umesaki; Hiroshi Fukumasu; Masato Miyama; Masami Kawabata; Sachio Ogita
We measured the plasma granulocyte colony stimulating factor (G-CSF) concentrations in pregnant women to evaluate the association between G-CSF and increased neutrophil counts that has been observed during pregnancy. We examined 96 pregnant and 10 nonpregnant women. The G-CSF concentrations were assayed using a sandwich enzyme immunoassay. The G-CSF concentrations in pregnant women were significantly higher at all times than those of nonpregnant women. The G-CSF concentrations were also significantly higher during than before labor. The plasma G-CSF concentrations were positively correlated with the neutrophil counts during the 3rd trimester only. In conclusion, increased G-CSF concentrations may be related to the increases in neutrophil counts in pregnant women, especially during the 3rd trimester.
Gynecologic and Obstetric Investigation | 1995
Hiroshi Tsuda; Masami Kawabata; Kazume Kawabata; Kumio Yamamoto; Atsuo Hidaka; Naohiko Umesaki
Transvaginal ultrasound (TVS) is generally considered superior to transabdominal ultrasound (TAS) in the estimation of endometrial abnormalities. A disadvantage of TVS is the limited field of view. The purpose of this study is a comparison between TAS and TVS for endometrial cancer screening. Ninety-one postmenopausal women were included. They were evaluated by TAS, TVS, and endometrial tissue sampling. The mean endometrial thickness estimated by TVS was larger than that obtained by TAS (p < 0.0001). Sensitivity and specificity of TAS were 83.3 and 58.8% and of TVS 100 and 54.1%, respectively. We conclude that TVS might be superior to TAS, especially in patients with a retroflexed uterus.
Journal of Ultrasound in Medicine | 1997
Hiroshi Tsuda; K Murata; Masami Kawabata; Kumio Yamamoto
This study was undertaken to assess the capabilities of intrauterine ultrasonography performed while inflating the endometrial cavity with fluid and magnetic resonance imaging as a means to assess the depth of myometrial invasion by endometrial cancer preoperatively. Twenty women with endometrial disorders underwent preoperative intrauterine ultrasonography and magnetic resonance imaging. We introduced the probe and hysteroscope simultaneously into the uterine cavity and observed both the uterine cavity surface and cross‐sectional uterine muscle. We classified the depth of myometrial invasion as none, superficial (less than half of the myometrium), or deep (more than half of the myometrium). The accuracy of magnetic resonance imaging and intrauterine ultrasonography in assessing the depth of myometrial invasion was 85%. In two cases, intrauterine sonography was able to demonstrate superficial myometrial invasion that could not be diagnosed by magnetic resonance imaging. In contrast, intrauterine ultrasonography was unable to diagnose myometrial invasion in two cases in which magnetic resonance imaging could diagnose it. Intrauterine sonography may be useful for estimation of myometrial invasion of endometrial cancer.
Gynecologic and Obstetric Investigation | 1995
Hiroshi Tsuda; Masami Kawabata; Naohiko Umesaki; Kazume Kawabata; Sachio Ogita
It is generally recognized that an endometrial thickness of 4-8 mm is considered a definite cutoff point for detection of endometrial malignancy by transvaginal sonography. We report on 2 patients with endometrial cancer and on 1 with endometrial hyperplasia, in each of whom endometrial thickness was < 4 mm.
Gynecologic and Obstetric Investigation | 1997
Hiroshi Tsuda; Kumio Yamamoto; Masami Kawabata; Touman Lee; Atsuo Hidaka
Platinum compounds are thought to be concentration- and time-dependent, but intravenous (i.v.) administration does not afford prolonged high platinum concentration in tumor tissue. In order to examine the influence of long-term local continuous (LC) injection of carboplatin, a pharmacokinetic study was performed. Twenty-six patients with uterine cancer were included. I.v. administration (11 patients): carboplatin (210 mg) was given i.v. and samples of target tissue were obtained at operation about 2 or 24 h after administration. LC administration (15 patients): the 21-gauge needle was implanted at the uterine cervix, and carboplatin was injected continuously (30 mg/day) for 3, 7 or 14 days using an external pump. The tissue platinum concentration was measured in the pelvic organs. The mean platinum levels at the cervix and vaginal wall in the LC (7 days) group were higher than those in the i.v. (2 h) group (p < 0.01). With LC injection, sustained platinum levels were maintained in the pelvic organs for a long time, with very few side effects. LC injection may be advantageous on the basis of pharmacokinetics.
European Journal of Obstetrics & Gynecology and Reproductive Biology | 1993
Hiroshi Tsuda; Masami Kawabata; Naohiko Umesaki; Kazume Kawabata; Sachio Ogita
We evaluated the usefulness of transabdominal ultrasonography (TAS) for endometrial abnormalities in postmenopausal women. A total of 232 postmenopausal women were examined by TAS and endometrial sampling. Abnormal findings, including endometrial hyperplasia, atypical hyperplasia and endometrial cancer, were noted in 0.7% (1/41) of sonographically measured endometrium < 2 mm and in 15.4% (14/91) of measurements > or = 2 mm. Endometrial cancer was found in 5.9% in the postmenopausal bleeding group (n = 85) and in 1.4% in the symptom-free group (n = 147). With one exception, all endometrial abnormalities were in endometrial thickness > or = 2 mm. We conclude that TAS has limitations as a technique but is useful in deciding which postmenopausal women require endometrial biopsy.
American Journal of Obstetrics and Gynecology | 1992
Naohiko Umesaki; Satoshi Uda; Masami Kawabata; Sachio Ogita
OBJECTIVE To elucidate the role of peritoneal macrophages in infertility, we investigated how the presence of peritoneal macrophages would affect fecundity in mice. Moreover, we also studied the effects of interleukin-1 on embryonic development. STUDY DESIGN Mice were administered OK-432 intraperitoneally to induce macrophage infiltration of the peritoneal cavity; ovulation was then induced and animals were mated. On day 13 of gestation, fetuses were counted. After injection of OK-432 or interleukin-1, the mice were mated. Three days later, embryos were collected and the stage of embryo development was determined. RESULTS In mice given OK-432 (n = 33), four (12%) became pregnant and the mean litter number was 6.0 +/- 3.6, whereas in the control group 23 of 30 mice (77%; p < 0.01) became pregnant and the litter number was 14.1 +/- 5.3 (p < 0.01). OK-432 and interleukin-1 administered intraperitoneally significantly suppressed embryo development (p < 0.01). CONCLUSION Increased numbers of peritoneal macrophages negatively affect fecundity, probably by suppressing embryonic development.
Clinical Cancer Research | 1999
Tomoaki Kusume; Hiroshi Tsuda; Masami Kawabata; Takeshi Inoue; Naohiko Umesaki; Tomoko Suzuki; Kumio Yamamoto