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T Kurabayashi

Publications and source records attributed to T Kurabayashi.

72 records · Page 4Linked to original sources
PubMed1995

Effects of progesterone on the metabolism of cancellous bone in young oophorectomized rats.

The effects of progesterone on cancellous bone in young rats were evaluated. Fifty female rats aged 90 days were divided into 5 groups: (1) Sham-operated controls (SHAM); (2) oophorectomized (OVX) rats; (3) OVX rats treated with estrogen (OVX+E); 4) OVX rats treated with progesterone (OVX+P); and (5) OVX rats treated with estrogen and progesterone (OVX+EP). After surgery, some animals were treated subcutaneously (s.c.) with 0.5 mg of estradiol dipropionate depot, with 5 mg of hydroxyprogesterone capronate depot, or with both hormones, at intervals of 7 days. After 180 days, the bone mineral density (BMD) and bone histomorphometry of their lumbar vertebrae and serological parameters were measured. In the OVX+P group, the BMD and the bone volume as shown by bone histomorphometry were slightly higher than in the OVX group, but not significantly. These parameters in the OVX+E and OVX+EP groups were significantly higher than in the OVX group. The OVX+P group showed a significant increase in the labeled surface and a decrease of the osteoclast number, compared to the OVX group. The OVX+P group showed increases of serum alkarine phosphatase and osteocalcin. From these results, it can be concluded that progesterone treatment might intensify bone formation and suppress bone resorption on cancellous bone in oophorectomized rats, although progesterone alone does not have a positive effect on BMD and bone volume.

Animals↗
PubMed1995

[The significance of bone mineral density measurement of premenopausal women].

We examined the starting age for measuring bone mineral density (BMD) in premenopausal women to detect osteopenia as soon as possible. BMD of the second to fourth lumbar spine vertebrae was measured by dual-energy X-ray absorptiometry to determine normal values for 500 healthy premenopausal women (aged from 17 to 55). We found the rate for low BMD premenopausal women, whose BMD was under the peak bone mass-2SD. And we compared normal BMD women with low BMD women with reference to menstrual history, obstetrical history, and life style, by means of a questionnaire. The peak bone mass of premenopausal women was reached between 35 and 39 years of age (1.059 +/- 0.097g/cm2). The low BMD rate was 7% in all premenopausal women, and increased to 13.5% at from 45 to 49 years. On the other hand, it was only from 5.7 to 7.4% even at from 20 to 29 years. There was the positive correlation between BMD and the body mass index (BMI). There was no statistically significant difference between the low BMD women and the normal BMD women in menstrual history, obstetrical history or life style (parity was 1.7 +/- 1.6 and 1.1 +/- 1.2, respectively, p < 0.05). We concluded that premenopausal women should have their BMD measured after aged 45, and be measured once from 20 to 40 years of age if possible.

Absorptiometry, Photon↗
PubMed1995

[Study on the relationship between hormonal cytology and bone mineral density in postmenopausal women].

We assessed the relationship between bone mineral density (BMD) and hormonal cytology in 181 postmenopausal women. BMD was measured by dual energy X-ray absorptiometry (DXA). Age, height, weight, body mass index (BMI), age at menopause, hormonal cytology (eosinophilic index (EI), karyopyknotic index (KPI) and maturation value (MV)) and estradiol were investigated. A positive correlation was found between BMD and hormonal cytology (EI r = 0.17 p < 0.05, KPI r = 0.19 p < 0.05 and MV r = 0.37 p < 0.005). The low BMD group (BMD < 0.8g/cm2 n = 87) had significantly lower hormonal cytology than the normal BMD group (BMD > or = 0.8g/cm2 n = 94). The receiver operating characteristic curve analysis showed MV at 30 was available for the cutoff point in predicting osteopenia. MV < 30 detected osteopenia (BMD < 0.8g/cm2) as 0.76 in sensitivity and 0.65 in specificity. These findings suggest that hormonal cytology is useful for screening osteopenia in post-menopausal women.

Absorptiometry, Photon↗
PubMed1994

Effect of hormone replacement therapy on bone and lipid metabolism in women oophorectomized for the treatment of gynecologic malignancies.

OBJECTIVE: Our purpose was to evaluate the effects of hormone replacement therapy (HRT) on bone and lipid metabolism in women oophorectomized for the treatment of gynecologic malignancies. METHODS: Bone mineral density (BMD), bone metabolic markers, sex hormones and lipoproteins were measured in three groups of age- and body mass-matched subjects. The subjects consisted of HRT(+) patients, i.e. those given HRT after oophorectomy (n = 39), HRT(-) patients, who received no HRT (n = 15), and controls comprising premenopausal women with no history of oophorectomy (n = 36). RESULTS: BMD decreased significantly in the HRT(-) patients, but no decrease in BMD was observed in the controls or HRT(+) patients. HRT was effective in preventing bone loss by reducing high-turnover osteopenia. HRT reversed the negative trends in lipoprotein profiles by lowering low-density lipoprotein cholesterol and increasing high-density lipoprotein cholesterol. There were no serious side effects or recurrences among the HRT(+) patients. CONCLUSION: HRT appeared to have beneficial effects on bone and lipid metabolism in oophorectomized patients treated for gynecologic malignancies.

Adult↗
PubMed1994

Transformation of Pseudomonas putida by electroporation.

The optimum electrotransformation conditions were determined for Pseudomonas putida PpY101 with plasmid pSUP104 (9.5 kb) and pSR134 (18.6 kb). Field strength was a very important parameter for electrotransformation efficiency. Optimum efficiencies (1.1 x 10(5) transformants/micrograms DNA) with pSUP104 and pSR134 were obtained at a field strength of 12.5 kV/cm, a time constant of about 4.5 ms (resistance setting of 200 ohms), a supercoiled DNA concentration of 100 ng/ml, and a cell concentration of 10(9)/ml. Because the efficiency obtained is high enough, electrotransformation is useful for the direct cloning of P. putida PpY101. No significant relationship between plasmid size and electrotransformation efficiency was observed. These efficiencies were about 4.5 times higher than those using the MgCl2 method. Under these conditions, electrotransformation efficiencies of relaxed plasmid DNA treated with topoisomerase I and that linearized by EcoRI digestion were high.

Biotechnology↗
PubMed1994

[Effect of hormone replacement therapy on lipid metabolism in patients with premature ovarian failure and Turner's syndrome].

Premature ovarian failure (POF) and Turner's syndrome patients who are also hypoestrogenomic, like postmenopausal women, are considered to be a high risk group for hyperlipemia. Our long-term study was conducted to evaluate the effect of hormone replacement therapy (HRT) on lipid metabolism in 16 POF and 10 Turner's syndrome women. 1. The initial average total cholesterol (TC) of the untreated and treated POF patients (209, 196mg/dl) and that of untreated and treated Turner's syndrome patients (213, 240mg/dl) were significantly higher than those in the control group (175mg/dl) except treated POF patients. LDL cholesterol (LDL-C) of the untreated and treated POF patients (135, 113mg/dl) and that of untreated and treated Turner's syndrome patients (142, 144mg/dl) were significantly higher than those in the control group (108mg/dl) except treated POF patients. In comparison to healthy women of a similar age, POF and Turner's syndrome patients were at high risk of hyperlipemia because of higher serum TC and LDL-C levels. 2. After HRT for 2 years, LDL-C decreased by 18% and 13%, and HDL cholesterol increased by 38% and 41% in POF and Turner's syndrome patients, respectively. Hence AI decreased by 40% and 50% respectively. The younger the hyperlipemic patients are, the higher the relative risk for atherosclerosis is. The results of this study suggest that, because of the beneficial effects of HRT on serum lipid metabolism, it can help to prevent the development of coronary heart disease.

Adult↗
PubMed1994

[Assessment of osteoporosis in the local population by means of a portable dual energy X-ray absorptiometry unit].

We assessed bone mineral density (BMD) in the local population by means of a portable dual energy X-ray absorptiometry (DXA) unit. BMD was measured by DXA in 197 women (62 premenopausal and 135 postmenopausal) in Shiunji town. Age, height, weight, body mass index (BMI), menstrual history, obstetric history, habits, symptoms and hormonal cytology (eosinophilic index (EI), karyopyknotic index (KPI) and maturation value (MV)) were investigated. A negative correlation (r = -0.645, p < 0.01) was found between BMD and age. Low BMD (BMD < 0.8g/cm2) was found at a rate of 3.2% in premenopausal women and 51.1% in postmenopausal women. The low BMD group of postmenopausal women had significantly lower BMI and higher age at first delivery than the normal BMD group (BMD > or = 0.8g/cm2). There were no differences between the 2 groups in other factors. We found a positive correlation between BMD and hormonal cytology (KPI and MV). These findings suggest that the rate of osteopenia in postmenopausal women is high than expectation and it is difficult to predict bone loss by symptoms, history and habits. The portable DXA unit is useful for screening osteopenia in local populations.

Absorptiometry, Photon↗
PubMed1994

[A study on bone metabolism in woman with hyperprolactinemia].

We studied bone metabolism in hyperprolactinemia in 21 hyperprolactinemic women, and compared it with 57 normal subjects. Second to fourth lumbar bone mineral density (BMD) was measured by dual energy X-ray absorptiometry (DXA). The mean BMD (g/cm2) in hyperprolactinemic women was 9% less than in normal subjects (0.940 +/- 0.115 (SD) vs. 1.030 +/- 0.106, p < 0.05). A negative correlation was found between BMD and the duration of hyperprolactinemia. The analysis of bone metabolic parameters, bone turnover, bone formation and bone absorption showed that they increase in the hyperprolactinemic state. The main mechanism of BMD loss in hyperprolactinemia is probably due to hypoestrogenemia, but a direct effect of prolactin cannot be excluded.

Absorptiometry, Photon↗
PubMed1993

Effect of hormone replacement therapy on spinal bone mineral density and T lymphocyte subsets in premature ovarian failure and Turner's syndrome.

OBJECTIVE: Our purpose was to evaluate the effect of hormone replacement therapy (HRT) on bone metabolism and the immunological change in premature ovarian failure (POF) and Turner's syndrome. METHOD: The study was conducted on 17 POF patients, 10 Turner's syndrome patients and 35 control subjects aged 20-40 years. Bone mineral density (BMD) of lumbar vertebra by dual energy X-ray absorptiometry, serum bone metabolic parameters and T lymphocyte subsets in the peripheral blood were investigated. RESULT: The untreated and treated patients of POF (0.829 +/- 0.077, 0.918 +/- 0.094 g/cm2) and the untreated and treated patients of Turner's syndrome (0.647 +/- 0.037, 0.885 +/- 0.148 g/cm2) showed spinal osteopenia compared with the control group (1.039 +/- 0.107 g/cm2). They showed a significantly lower percentage of CD4 and a ratio of CD4/CD8 in T lymphocytes as compared with the control group before HRT. CONCLUSION: POF and Turner's syndrome patients showed marked spinal osteopenia and abnormal T lymphocytes subsets. HRT slightly improved their BMD and immunological status.

Absorptiometry, Photon↗
PubMed1993

Criteria for differentiating superficial from deep lobe tumours of the parotid gland by computed tomography.

A retrospective analysis of the CT images of 36 parotid tumours was undertaken to evaluate the potential value of certain criteria for distinguishing tumours of the superficial lobe from those of deep lobe. The criteria were one of three hypothetical lines indicating the course of the facial nerve, or the course of Stensen's duct. The lines representing the course of the facial nerve are straight lines connecting the main facial nerve trunk with the lateral border of the masseter (line 1), the lateral border of the mandible (line 2) and the retromandibular vein (line 3). Line 1 was significantly more accurate than line 2 or line 3 (P < 0.05); all of superficial (28/28) and 63% of deep lobe tumours (5/8) were correctly diagnosed. On the other hand, when Stensen's duct was used as the criterion, all the superficial (8/8) and deep lobe tumours (3/3) were correctly diagnosed. However, this criterion could be applied only to those cases where both the tumour and Stensen's duct were demonstrated on the same CT-sialogram.

Adenolymphoma↗
PubMed1993

Time-course of vertebral and femoral bone loss in rats administered gonadotrophin-releasing hormone agonist.

This study was carried out (1) to compare the time-course of the change in bone metabolism in rats administered gonadotrophin-releasing hormone agonist (GnRHa) and bilaterally ovariectomized (OVX) rats and (2) to investigate the changes in bone metabolism after discontinuance of GnRHa. Seventy female Sprague-Dawley rats, aged 90 days, were divided into four groups. Group 1 underwent a sham operation, group 2 was surgically ovariectomized and group 3 was given a GnRHa (leuprorelin acetate for depot suspension) s.c. injection every 30 days. Group 3 was further divided into three subgroups: rats were administered GnRHa for 12 months (GnRHa 12M), 6 months (GnRHa 6M) or 3 months (GnRHa 3M). Group 4 served as a basal control. The bone mineral density (BMD) of lumbar vertebrae and femoral bone, measured by dual-energy X-ray absorptiometry, and the serum bone metabolic parameters were determined every 45-90 days. The bone histomorphometry of lumbar vertebra was measured on days 180 and 360 after surgery. GnRHa 12M rats showed significantly lower BMD of vertebrae and femoral bone, lower bone volume and higher bone turnover compared with sham-operated rats and those with secondary hyperparathyroidism on days 180 and 360. Their time-course for changes in bone metabolism was almost the same as that of OVX rats. GnRHa-discontinued rats showed a recovery of bone turnover. The recovery of BMD in GnRHa 6M rats was smaller than that of GnRHa 3M rats after GnRHa discontinuance. The bone volume for GnRHa 6M rats was significantly lower than that for GnRHa 3M on day 360.

Absorptiometry, Photon↗
PubMed1991

CT findings in primary osteosarcoma of the jaw.

Findings of computed tomography (CT) in five patients with osteosarcoma of the jaw are presented. CT played an important role in the assessment of the tumour extent before the planning of treatment for both primary and recurrent jaw osteosarcoma. Plain CT was capable of demonstrating subtle bony change (cortical reaction and calcification) and medullary tumour extension without interference from other superimposed bones. Tumour vasculature was well represented by thin-slice CT scan with intravenous bolus injection of contrast medium. We emphasize the importance of preoperative CT scanning from both a radiological and surgical point of view when confronted with a tumour of the maxilla or mandible.

Adult↗
PubMed1991

Differential diagnosis of submandibular cystic lesions by computed tomography.

A retrospective analysis of 35 submandibular cystic lesions was undertaken to assess the usefulness of CT in their differential diagnosis. Lesions were analysed on the basis of extent, shape and density. It was found that all those lesions that extended into both the sublingual and the anterior part of the submandibular spaces could be diagnosed as ranulas (10/10) and all those limited to the posterior part as lateral cervical cysts (8/8). Those lesions that extended to the sublingual, but not the anterior part of the submandibular space, were dermoid cysts if they had a smooth margin (2/2), and probably ranulas when it was concave (4/5). Those lesions that extended into the anterior part of the submandibular but not the sublingual space were ranulas on the basis of a multilocular or concave margin (3/3), but if they had a smooth margin (3/7) they could not be differentiated from dermoid cysts (4/7). Although CT density was less valuable for the differential diagnosis, both ranulas and dermoid cysts could be excluded if it was similar to that of muscle.

Adolescent↗
PubMed1991

Radiographic quality and patient discomfort in sialography: comparison of iohexol with iothalamate.

We have compared the usefulness of a newly developed, low osmolality contrast medium, Omnipaque 350 (75.49% iohexol, 350 mgI ml-1), for sialography with one of the established, Angioconray (80% sodium iothalamate, 480 mgI ml-1), in a double-blind, prospective randomized clinical trial in 80 patients. The diagnostic quality of the sialograms, pain during the procedure and discomfort subsequently were investigated. There was no difference in either group between the number of sialograms judged as diagnostically useful, although those of excellent quality were significantly more frequent in the Angioconray group. The level of pain on injection of the medium was significantly lower in the Omnipaque group. Eighteen per cent of the patients with Omnipaque had severe or moderate pain on injection of the contrast medium, while 63% had such pain with Angioconray. There was no difference in postprocedural discomfort between the two contrast media. We concluded that the low osmolality contrast medium is more favourable for sialography despite its lower iodine content.

Adult↗
PubMed1988

Sialographic images of pathological changes in the mouse parotid gland.

In order to correlate pathological changes of mouse parotid glands with their sialographic images, we conducted studies on mice with known pathological changes: mice with Stensen's duct ligated, NZB mice with a systemic auto-immune disease, and aged mice. The sialographic images were found to be specific for the pathological changes: The glands after ligation of Stensen's duct were characterized by dilated, large excretory ducts with a reduced system of peripheral ducts; the glands of NZB mice showed lobular leakage of the contrast medium from small excretory ducts; and the glands of aged mice showed a great reduction in the ductal system. It is concluded that sialography yields useful information on the pathological changes of the ductal systems in the mouse parotid gland.

Aging↗
PubMed1987

Postnatal development of the duct system in the mouse parotid gland.

The morphology of the parotid gland in adult mice is mouse strain-specific. C57BL/6 and C3H/He strains of mouse are representatives of two types of the morphology identified previously. The postnatal development of such morphologic differences was investigated by sialography of excised glands of these strains of mouse. It was observed that the mouse strain-dependent morphological characteristics were already present at birth, except for the branching pattern of the peripheral duct system, which became differentiated at 3 weeks of age. These results indicate that the C3H/He mouse-specific branching pattern of the peripheral ducts reflects the profile of matured secretory units and ducts, and that the C57BL/6 mouse-specific pattern resembles that of an immature C3H/He mouse.

Animals↗