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Journal of Steroid Biochemistry | 1989

Estrone sulfate and sulfatase activity in human breast cancer and endometrial cancer

Kazuo Naitoh; Hideo Honjo; Takara Yamamoto; Mamoru Urabe; Yoshio Ogino; Tadaki Yasumura; Toshio Nambara

Estrone sulfate (E1-S) in the serum and tissues of patients with breast cancer or endometrial cancer was measured by a direct radioimmunoassay without hydrolysis. The concentration of E1-S in breast cancer tissue was 1.64 +/- 0.28 ng/g wet wt (+/- SE), lower than in surrounding normal breast tissue (4.46 +/- 1.23). Estradiol-17 beta(E2)/E1-S was higher in endometrial cancer tissue than normal endometrial tissue. Estrone sulfatase activity in breast cancer tissue was 0.81 +/- 0.23 nmol/h/mg protein, higher than in surrounding normal breast tissue (0.35 +/- 0.11). These results suggest that E1-S, which is abundant in the peripheral circulation, is hydrolyzed by sulfatase in breast cancer tissue or endometrial cancer tissue and liberates free estrogens, which may stimulate the growth of these malignant tumors.


American Journal of Kidney Diseases | 1988

Effect of Cyclosporine on the Endocrine and Exocrine Pancreas in Kidney Transplant Recipients

Norio Yoshimura; Ichiro Nakai; Yoshihiro Ohmori; Ichiro Aikawa; Masatake Fukuda; Tadaki Yasumura; Suguru Matsui; Takahiro Oka

In order to assess whether cyclosporine (CsA) affects the endocrine and exocrine pancreas, 105 patient courses comprised of 87 living related donor (LRD) and 18 cadaver donor (CAD) transplants treated with cyclosporine and prednisolone (Pred) were compared with the results of historical controls of 170 LRD and 10 CAD transplants treated with azathioprine (Az) and Pred. All of the recipients were followed for over 6 months after transplantation. There were no differences in age, sex, Broca index, family history, and preoperative evaluation on diabetic dispositions between the two treatment groups. The incidence of diabetes mellitus (DM) requiring insulin therapy was higher in CsA-treated recipients (18/105, 17.1%) than in Az-treated recipients (23/180, 12.8%; P less than 0.05), although both the daily Pred and cumulative doses of methylprednisolone (MP) at the onset of DM were significantly smaller in the CsA group than in the Az group (26.1 +/- 2.2 mg v 41.4 +/- 3.4 mg, P less than 0.01 and 3,086 +/- 626 mg v 7,133 +/- 1,129 mg, P less than 0.01, respectively). Diabetic patients with CsA showed higher levels of blood glucose (401 +/- 46 mg/dL), but lower amounts of urinary glucose (40 +/- 4.3 g/d) compared with patients treated with Az (239 +/- 31 mg/dL, and 61.4 +/- 4.6 g/d, respectively, P less than 0.05). In the CsA group, the onset of DM was related to high CsA plasma trough levels (greater than 350 ng/mL) in 23% of patients. Insulin could be withdrawn within 3 months in six of eight patients who had been converted from CsA to Az.(ABSTRACT TRUNCATED AT 250 WORDS)


Journal of Chromatography B: Biomedical Sciences and Applications | 1994

Determination of a new immunosuppressant, mycophenolate mofetil, and its active metabolite, mycophenolic acid, in rat and human body fluids by high-performance liquid chromatography

Nobuyuki Sugioka; Hikaru Odani; Toshio Ohta; Hideki Kishimoto; Tadaki Yasumura; Kanji Takada

Mycophenolate mofetil, a new immunosuppressant, is a morpholinoethyl ester of mycophenolic acid. A new selective, sensitive and simple high-performance liquid chromatographic method was developed for the determination of mycophenolic acid and mycophenolate mofetil in biological samples. The preparation of samples was based on liquid-liquid extraction. The compounds were separated on a CN column using acetonitrile-0.01 M phosphate buffer (1:4, v/v) as the mobile phase. UV detection was used at wavelengths 215 and 304 nm. The detection limit was 5 ng per injection volume. This method enabled pharmacokinetic and pharmacodynamic studies in humans and rats.


Surgery Today | 1988

Experience with 247 living related donor nephrectomy cases at a single institution in Japan

Tadaki Yasumura; Ichiro Nakai; Takahiro Oka; Yoshihiro Ohmori; Ichiro Aikawa; Keisuke Nakaji; Norio Yoshimura; Yoshihiro Nakane

There is currently much concern over the morbidity and mortality of donors undergoing nephrectomy for living related renal transplants. Between April, 1970 and July, 1986, 247 cases of living related renal transplants were performed at the Second Department of Surgery, Kyoto Prefectural University of Medicine. The average age of the donors was 50.3±9.7 years, 81 per cent of the donors being parents of the recipients. Minor abnormalities which did not affect the donors suitability were found in 71 cases. Nephrectomies were performed extraperitoneally in all cases. Peri-operative complications, including wound complications in 13 cases, urinary infection in 12 cases and pulmonary complications and arrythmia in 4 cases, were considered to be minor in nature. A variety of renal function tests, carried out two weeks after nephrectomy revealed normal levels, although they had become slightly worse than those estimated pre-operatively. Long-term sequalae in the follow-up period from 18 months to 16 years and 2 months, was studied on 124 donors who answered questionnaires. Currently, there are 5 late deaths, none of which are directly related to the nephrectomy. Of the 124 donors, 85.5 per cent stated that there had been no change in their physical states following surgery. Pain or a feeling of discomfort at the wound site was reported by 10 donors (8.1 per cent) and hypertension was observed only in 3 (2.4 per cent). No major complication directly related to the donor nephrectomy was found, except for one case of incisional hernia. The donor nephrectomy operation thus appeared to be quite safe, and successful long-term sequelae can be obtained if the donor is selected carefully, according to the strict prospective evaluation of medical state and renal functions.


Pharmaceutical Research | 1986

Enhanced selective lymphatic delivery of cyclosporin A by solubilizers and intensified immunosuppressive activity against mice skin allograft

Kanji Takada; Hiroyuki Yoshimura; Hiroshi Yoshikawa; Shozo Muranishi; Tadaki Yasumura; Takahiro Oka

The absorption and lymphatic delivery of a new immunosuppressive drug, cyclosporin A (CsA), were studied in rats by administering CsA orally after solubilization with HCO-60 (polyoxyethylated hydrogenated castor oil), sugar ester, and oils. After the administration of solubilized CsA (7 mg/kg) to rats with thoracic lymph duct cannulas, both plasma and lymph CsA levels were measured over 6 hr. The lymph CsA levels were strongly affected by the solubilizers. The rank order of the solubilizers in enhancing lymph absorption was HCO-60 (57 µg/ml) > sugar ester (46 µg/ml) > sesame oil (3.5 µg/ml) > linoleic acid (0.4 µg/ml), where the parentheses show the maximum lymph CsA levels. Plasma CsA levels were below 2 µg/ml in each group of animals and were barely altered by the solubilizers. These results support the selective lymphatic delivery of CsA with solubilizers such as HCO-60 and sugar ester. The immunosuppressive activity of CsA (1 mg/kg) solubilized with HCO-60 was nearly equivalent to the sesame oil solution with 7 to 15 mg/kg CsA in the skin-allograft mice model.


Surgery Today | 1988

Infiltrating ductal carcinoma developing within cystosarcoma phyllodes —A case report—

Tadaki Yasumura; Suguru Matsui; Takashi Hamajima; Kei Nagashima; Hisakazu Yamagishi; Ichiro Aikawa; Takahiro Oka; Toshihiro Nakae; Nobuo Shimada

Malignancy in cystosarcoma phyllodes is uncommon and often confined to the stromal element. An extremely rare case of infiltrating ductal carcinoma developing within the stroma of cystosarcoma phyllodes is reported herein. A breast tumor with a diameter of 15 cm, which was diagnosed as cystosarcoma phyllodes, was excised from the right breast of a 47-year old woman. The histopathological examination revealed that hyperplastic ductal epithelial cells with dark cytoplasm and enlarged hyperchromatic nuclei were infiltrating the stroma. Thus, a diagnosis of ductal carcinoma within cystosarcoma was made. Subsequently, a standard radical mastectomy was performed. No recurrence or metastasis has been observed over the post-operative period of 5 years and 6 months.


International Journal of Urology | 1997

Pharmacokinetic Studies of Mycophenolate Mofetil in Rat Kidney Allograft Recipients

Hitoshi Inoue; Nobuyuki Sugioka; Kazuhisa Hayashida; Tadaki Yasumura

Background A pharmacokinetic estimation of the immunosuppressive activity of mycophenolate mofetil (MPM) was performed in rats with transplanted kidney allografts.


Surgery Today | 1990

The effect of adjuvant therapy with or without tamoxifen on the endocrine function of patients with breast cancer

Tadaki Yasumura; Toshikazu Akami; Manabu Mitsuo; Takahiro Oka; Kazuo Naitoh; Takara Yamamoto; Hideo Honjyo; Hiroji Okada

The ovarian and pituitary functions of 64 operable breast cancer patients undergoing adjuvant therapy with cytotoxic chemotherapy and/or tamoxifen were investigated. The post menopausal patients, divided into 3 treatment groups, one with tamoxifen alone, one with tamoxifen and chemotherapy and the other with chemotherapy alone had serum estradiol 17-β (E2) and progesterone levels lower than the evaluable limits. Although there was no significant difference in the level of estrone sulfate (E1-S) between these three groups, the level of lutainizing hormone (LH) and follicle stimulating hormone (FSH) in the patients treated with tamoxifen alone and tamoxifen and chemotherapy were significantly lower than those treated with chemotherapy alone. The decrease in gonadotropin levels induced by tamoxifen treatment was reversible as it appeared after the initiation of tamoxifen and recovered after its cessation. In the premenopausal patients, a group treated with tamoxifen and chemotherapy had significantly higher E1-S, E2 and progesterone levels and significantly lower gonadotropin levels than a group treated with chemotherapy alone or one treated with a cyclophosphamide regimen. These increases in the levels of estrogen and progesterone were also reversible, and induced by tamoxifen. Thus, adjuvant endocrinochemotherapy causes profound alteration in the hypothalamo-pituitary-ovarian axis and therefore, monitoring a variety of hormonal levels is thought to be necessary for assessing the consequences of adjuvant therapy in breast cancer patients, especially in premenopausal patients using tamoxifen.


Surgery Today | 1994

Idiopathic portal hypertension in renal transplant recipients: report of two cases.

Norio Yoshimura; Takahiro Oka; Yoshihiro Ohmori; Tadaki Yasumura; Hiroshi Kohnosu; Teisei Kobashi

We present herein the cases of two patients who developed idiopathic portal hypertension (IPH) following renal transplantation. Both patients had been treated with azathioprine and prednisolone for 6 years and 4 months and for 4 years and 7 months, respectively, and presented with splenomegaly and thrombocytopenia suggesting hypersplenism. Celiac angiography showed a dilated splenic artery and vein in both patients. When the splenic artery was obliterated with a balloon catheter in case 1, the portal venous pressure decreased from 51 cmH2O to 36 cmH2O and the direction of the superiomesenteric venous blood flow became hepatopetal rather than hepatofugal. These results suggested that the spleen might have played an important role in the development of IPH in these two patients. A splenectomy was therefore performed, immediately following which the portal venous pressure decreased remarkably, and the esophageal varices disappeared during the postoperative follow-up period. Microscopic examination of liver biopsies taken at the operation revealed lymphoplasmacytic infiltration with bile duct hyperplasia but no evidence of periportal fibrosis, and electron microscopy demonstrated very mild perisinusoidal fibrosis. Thus, the histological changes seen in the livers of these patients seemed not to have caused the portal hypertension. In conclusion, although few patients develop IPH after renal transplantation, we should be aware of its possibility and consider splenectomy as the treatment of choice.


Surgery Today | 1989

Breast cancer arisingde novo in recipients of kidney allograft

Tadaki Yasumura; Yoshihiro Ohmori; Ichiro Aikawa; Kouhei Arakawa; Keisuke Nakaji; Ichiro Nakai; Takahiro Oka; Yoshihiro Nakane

Immunosuppressive therapy is not only an etiologic factor ofde novo malignant disease but it also accelerates progression of the already developed malignant disease in immunosuppressed recipients. Two cases ofde novo breast cancer arising in kidney transplant recipients are reported herein. A 25 year-old woman, transplanted one haploidentical kidney transplant 4 years and 9 months ago, developed a left breast tumor. Within one month the tumor had rapidly enlarged from 3.5 cm to 8 cm in diameter by the time she underwent a radical mastectomy. Nine axillary lymph nodes were positive for metastasis. Although her graft function had been poor due to chronic rejection, she was treated with standard immunosuppressive therapy, but not adjuvant therapy. Since local recurrent disease appeared two months postoperatively, the immunosuppressive therapy was ceased and60Co therapy started. Recurrent disease progressed rapidly, however, and she died 7 months after her operation. A 27 year-old woman, having allograft from an identical sibling, noted a right breast tumor, 8 years and 7 months later. Again the tumor had grown rapidly from 1.8 cm to 3 cm in diameter within one month. She underwent a standard radical mastectomy. One axillary lymph nodes was positive for metastasis. She has been treated with standard immunosuppressive therapy and adjuvant endocrinochemotherapy. Presently, she is alive with a well functioning graft and no disease.

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Takahiro Oka

Kyoto Prefectural University of Medicine

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Norio Yoshimura

Kyoto Prefectural University of Medicine

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Yoshihiro Ohmori

Kyoto Prefectural University of Medicine

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Ichiro Nakai

Kyoto Prefectural University of Medicine

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Ichiro Aikawa

Kyoto Prefectural University of Medicine

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Suguru Matsui

Kyoto Prefectural University of Medicine

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Kanji Takada

Kyoto Pharmaceutical University

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Chol Joo Lee

Kyoto Prefectural University of Medicine

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Hiroo Nakajima

Kyoto Prefectural University of Medicine

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Keisuke Nakaji

Kyoto Prefectural University of Medicine

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