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Biomedical subjects

K Naitoh

Publications and source records attributed to K Naitoh.

At least 19 recordsLinked to original sources
PubMed1992

Serum estradiol 17-sulphate and lipid peroxides in late pregnancy.

Estradiol 17-sulphate is readily converted to 2-OH or 4-OH estradiol 17-sulphate. The latter two strongly antagonize lipid peroxidation, which may play certain roles during pregnancy, such as pregnancy-induced hypertension. Serum estradiol 17-sulphate during mid and late pregnancy was measured using a direct radioimmunoassay without hydrolysis, and the level increased as pregnancy progressed. The levels in the sixth (20-23 weeks) and tenth months (36-39 weeks) of gestation were 1.42 +/- 0.04 nmol/l (mean +/- SD) and 3.42 +/- 1.09 nmol/l, respectively. The maternal venous levels before and at delivery and in the umbilical veins and artery were 3.38 +/- 0.83, 3.48 +/- 1.53, 4.11 +/- 1.40 and 4.30 +/- 1.81 nmol/l, respectively. The latter two values were slightly higher than the former two. Estradiol 17-sulphate in maternal venous blood began to decrease around delivery. Serum lipid peroxides were measured using the method of Yagi. Estradiol 17-sulphate and lipid peroxides showed a simple regression slope (r = -0.548, p less than 0.05) during late pregnancy. These results suggest that estradiol 17-sulphate may be converted to 2-OH or 4-OH estradiol 17-sulphate, which act as lipid peroxide scavengers during pregnancy.

Estradiol↗
PubMed1992

Toxicity studies of a synthetic antioxidant, 2,2'-methylenebis (4-ethyl-6-tert-butylphenol) in rats. 1. Acute and subchronic toxicity.

The acute and subchronic toxicity studies on 2,2'-methylenebis (4-ethyl-6-tert-butylphenol) (MBEBP) were conducted using male and female Wistar rats. In acute toxicity test, the LD50 values were estimated to be greater than 10 g/kg BW by oral and intraperitoneal administration in each sex. In subchronic toxicity test, groups of 10 rats of each sex were fed a diet containing 0.2, 1.0 or 5.0% of MBEBP and examined at 4 and 12 weeks. Body weight gain was significantly depressed at doses of 1.0 and 5.0% in both sexes, but the depression in the 1.0% group was severer than that in the 5.0% group in males. Hematological analysis showed slight but significant decrease of hemoglobin in the 1.0 and 5.0% groups of both sexes. Urine analysis showed no remarkable changes in all treated rats of both sexes. In biochemical analysis of serum, decrease of triglyceride level and cholinesterase activity, and increase of amylase activity were observed in treated rats. Histopathologically, testicular atrophy and decrease of spermatogenesis were observed in male rats fed 1.0 or 5.0% MBEBP for 4 and 12 weeks and vacuolization of parathyroid gland cells was observed in female rats fed 1.0 and 5.0% MBEBP for 12 weeks. In subchronic test, the lowest observable adverse effect levels for MBEBP toxicity were estimated to be 171 mg/kg BW/day in male rats and 180 mg/kg BW/day in female rats.

Administration, Oral↗
PubMed1992

Increased interleukin-6 activity in cardiac myxoma with mediastinal lymphadenopathy.

We report a case of cardiac myxoma with mediastinal lymphadenopathy which seems to be a very rare feature. Laboratory examination revealed high level of interleukin-6 (IL-6) activity in serum. Interestingly, after removal of cardiac myxoma, mediastinal lymphadenopathy disappeared on the chest CT and the level of serum IL-6 was decreased. These findings suggest that IL-6 which was probably derived from myxoma, may have played an important role in the development of lymphadenopathy.

Female↗
PubMed1991

Successful combined operation for Takayasu's arteritis.

We report a case of Takayasu's arteritis complicated with aortic regurgitation and severe stenosis of the left coronary ostium and the innominate artery. Simultaneous surgical treatment of aortic valve replacement, coronary ostium endarterectomy, and aortosubclavian artery bypass using saphenous vein were performed. We discuss the choice of simultaneous operation and the option of surgical treatment for coronary ostium lesion due to Takayasu's arteritis.

Aortic Valve Insufficiency↗
PubMed1991

[Concentration of nitrosodimethylamine in commercial pelleted experimental animal diets].

To know the conditions of contamination by the chemicals in the experimental animal diets, the contents of nitrosodimethylamine (NDMA) were analyzed in the diets for mice and rats. The raw materials of the diets were also analyzed. In addition, NDMA levels were determined in the diets which were stored long or heated in the autoclaves. The averages of NDMA in these diets were less than 10 ppb. In the raw materials, alfalfa contained a higher levels of NDMA. There was no clear tendency of increase or decrease in NDMA levels, when the diets were stored for six months at room temperature (23-25 degrees C) or at low temperature (7-10 degrees C). Heating the diets at 121 degrees C, no remarkable changes were observed in NDMA levels. It seems that little adverse influences on the conduct of the animal experiments would be anticipated by the NDMA in the commercial diets.

Animal Feed↗
PubMed1991

Biochemical and functional analysis of mixed isotype A beta E alpha class II molecules in Ed alpha transgenic mice.

We demonstrated the existence of mixed isotype A beta E alpha class II molecules in Ed alpha gene-introduced C57BL/6 (B6Ed alpha) transgenic mice. Immunoprecipitation and two dimensional (NEPHGE/SDS-PAGE) gel electrophoresis analysis of labeled B6Ed alpha spleen cell lysates using monoclonal anti-Ab beta antibody showed Ed alpha spots in addition to Ab beta and Ab alpha spots. We obtained alloreactive T cell clones from B6 anti-B6Ed alpha long-term cultures that recognized the Ab beta Ed alpha molecule. We also obtained antigen reactive T cell clones that recognized antigen in the context of Ad beta Ed alpha mixed isotype class II molecules. The importance of the mixed isotype class II molecules in relation to the expansion of the T cell specificity repertoire as well as autoimmune induction is discussed.

Animals↗
PubMed1990

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

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-beta (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.

Aged↗
PubMed1990

Estrone sulfatase activity in human uterine leiomyoma.

Human uterine leiomyoma is a benign tumor and its development is closely related to estrogen. In this study, estrone sulfatase (E1SF) activity and concentrations of estrone (E1) and estrone sulfate (E1S) were measured in endometrial, leiomyoma, and myometrial tissues of the same human uterus (n = 11) with a leiomyoma. E1SF activity in endometrial tissue overlying a leiomyoma was 2.62 +/- 0.29 nmole/hr/mg protein (mean +/- SD), this activity being significantly higher (P less than 0.01) compared with that in normal endometrial tissue (2.0 +/- 0.24 nmole/hr/mg protein). E1SF activity in normal endometrial tissue was significantly higher (P less than 0.001) compared with that in leiomyoma tissue (0.49 +/- 0.82 nmole/hr/mg protein) or myometrial tissue (0.76 +/- 0.10 nmole/hr/mg protein). We also found a significant difference (P less than 0.05) in E1SF activity between leiomyoma tissue and myometrial tissue. On the other hand, the E1 concentration in endometrial tissue overlying a leiomyoma (10.9 +/- 8.9 pg/mg protein) proved to be higher than that in endometrial tissue overlying normal myometrium (1.23 +/- 1.97 pg/mg protein). E1S concentrations in these tissues, however, were 631 +/- 339 and 902 +/- 482 pg/mg protein, respectively, these values showing a trend opposite that of the E1 concentration data. Thus, these results suggest that high E1SF activity and high E1 concentration in the endometrium overlying a leiomyoma may be related to estrogen supply to a uterine leiomyoma node.

Endometrium↗
PubMed1990

[Relapsing polychondritis in a patient with myelodysplastic syndrome].

Relapsing polychondritis is a rare disorder of uncertain origin characterized by recurrent inflammation of cartilage. A case of myelodysplastic syndrome (MDS) associated with relapsing polychondritis is reported. A 60-year-old man who had been diagnosed as MDS was admitted because of pain and swelling in the bilateral preauricular regions and cheek. A diagnosis of relapsing polychondritis was made by coexistence of auricular chondritis, arthropathy, ocular inflammation and audio-vestibular disturbance. He also developed ocular palsies and optic neuritis. He was treated with prednisolone, azathioprine, dapsone, and then with steroid pulse therapy. Moreover, plasmapheresis and high dose gamma-globulin therapy were undertaken. However, all these treatments were unsuccessful and he died of respiratory failure.

Azathioprine↗
PubMed1989

In vivo effects by estrone sulfate on the central nervous system-senile dementia (Alzheimer's type).

Seven women with senile dementia-Alzheimer's type (SDAT) were treated with conjugated estrogen [main content: estrone sulfate (E1-S)], at a dose of 1.25 mg/day over a 6-week period. A New Screening Test for Dementia developed by Japanese National Institute of Mental Health (NS) and the scores of Hasegawa Scale for dementia (HS) were performed every 3 weeks. Six women showed improvements in NS (P less than 0.05) and 5 women showed improvements in HS. Untreated women with SDAT did not show any improvement. Serum E1-S was measured by a direct radioimmunoassay. Serum E1-S was 911 +/- 156 pg/ml in 7 women with SDAT and lower than that of 7 normal women (1020 +/- 216 pg/ml). Following the treatment, serum E1-S increased to a level of 21.1 +/- 8.1 ng/ml. Estrone and estradiol-17 beta also increased. The results suggest a possibility for the future clinical use of estrogen for senile dementia, after careful clinical research trials including the side effects.

Aged↗
PubMed1989

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

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.

Adipose Tissue↗
PubMed1989

A modification of the sagittal splitting technique ensuring that the osteotomy split lies immediately medial to the lateral cortex.

A modification of Obwegeser's sagittal splitting method for the correction of mandibular prognathism has been developed. The anterior border of the proximal segment is partially removed at the beginning of osteotomy, which is carried out on the immediate inner surface of the lateral cortex. This osteotomy plane just under the lateral cortex, obtained by the use of a thin, disposable reciprocating sawblade, contributed to a lower incidence of postoperative lower lip hypaesthesia in the 14 cases presented.

Bone Marrow↗
PubMed1989

The platysma myocutaneous flap for oral reconstruction. Experience with MacFee's cervical incision.

The present study was performed to demonstrate and evaluate the effectiveness of the Platysma Myocutaneous Flap in conjunction with MacFee's cervical incision (MacFee, 1960) for reconstruction after oral cancer excision. Ten squamous cell carcinoma cases were provided for postoperative evaluation of tongue movement and aesthetic problems of the cervical skin. It was found that the thickness of the skin island was adequate for covering the oral defects and was not a hindrance to proper postoperative function. MacFee's incision improved the condition of the scar caused by flap elevation. The procedure for preparing the muscle pedicle beneath the cervical skin tunnel was carried out without much difficulty by carefully preparing the surgical field.

Adult↗
PubMed1989

Estrone sulfatase activity in normal and neoplastic endometrial tissues of human uterus.

Estrone sulfatase activity was measured in normal and neoplastic endometrial tissues of human uterus. The tissue homogenates were incubated in air with [3H] estrone sulfate (E1-S, 20 microM) at 37 degrees C for 30 min. After the enzyme reaction was terminated with ethyl ether, the ethyl ether extract was purified by thin-layer chromatography. The apparent Km of sulfatase was 3.0 microM, and the maximum velocity was 14.7 nmol/h/mg protein. Estrone sulfatase activity in endometrial tissues was detected throughout the menstrual cycle with no significant change. Moreover, estrone sulfatase activity in endometrial cells was not stimulated by the addition of progestogen. The enzyme activity in cancer tissue was significantly higher than in normal tissue. Thus we concluded that this enzyme may play a role in regulating the estrogen action by sifting the intracellular equilibrium between free estrogens and estrogen sulfates. We also concluded that in the endometrial cancer tissue, sulfatase appears to act on local production of estrone.

Endometrium↗
PubMed1989

[Tissue culture and estrogen, to clarify the roles of estrone sulfate].

Estrone sulfate (E1-S) has been shown to be quantitatively the most important estrogen in peripheral blood. But, the physiological and/or pathological role of E1-S is not yet clarified. At present, we tried to clarify it using tissue cultures. In tissue cultures of human endometrium, secretory endometrium showed higher activity of estrone sulfatase (E1----E1-S) than proliferative endometrium. Progesterone added in the medium induced an increase of estrone sulfotransferase in the proliferative endometrium. The results suggest a reducing effect of estrogen by progesterone in secretory endometrium in physiological conditions. Estrogen dependent malignant tumors (breast cancer, endometrial cancer) have high estrone sulfatase. It converts E1-S to E1 (----E2) which are abundant in these tumors. Ishikawa cell line increased estrone sulfotransferase activity with progesterone, somewhat like the physiological conditions. From out study in vivo, there is a possibility of some ameliorative effects of E1-S on the central nervous system of patients with senile dementia (Alzheimer's type). Effects of E1-S on central nerves were investigated using tissue cultures.

Alzheimer Disease↗
PubMed1989

[Therapeutic embolization of infantile hemangioendothelioma of the liver].

A distinct syndrome in infantile hemangioendothelioma consist of high-output congestive heart failure, hepatomegaly and cutaneous hemangiomas. Early therapy aimed at reduction of the shunt is essential if life is to be saved once cardiac failure becomes manifest. We report a case of infantile hemangioendothelioma with massive A-V and P-V shunt successfully treated by transcatheter embolization.

Age Factors↗