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T Shigematsu

Publications and source records attributed to T Shigematsu.

At least 37 records · Page 2Linked to original sources
PubMed2000

Effect of low-calcium hemodialysate on bone metabolism.

In the present study, we investigated the kinetics of bone metabolism by determining serum bone metabolic markers and quantifying bone mineral density by dual-energy X-ray absorptiometry to clarify the effect of long-term use of low-calcium hemodialysate on bone metabolism. After changing the calcium concentration in the dialysate from 3.0 mEq/l to 2.5 mEq/l, serum intact parathyroid hormone level, serum highly sensitive parathyroid hormone level, and serum bone metabolic markers were determined in ten patients with chronic nondiabetic renal insufficiency during 1 year. The doses of an oral phosphate binder and activated vitamin D were carefully regulated to control serum ionized calcium levels and serum inorganic phosphorus levels. Bone mineral density was determined at the distal 1/3 and 1/6 of the radius on the nonshunt side. As a result, the required amount of oral phosphate binder was increased; however, there was no need to significantly increase the amount of activated vitamin D. Intact parathyroid hormone showed no significant variation, but the highly sensitive parathyroid hormone was significantly increased. There were no significant changes in any bone metabolic markers or in bone mineral density. From these study results, it was found that it was difficult to increase the dose of activated vitamin D even if low-calcium hemodialysate was used, and that during use of the low-calcium hemodialysate the serum level of parathyroid hormone tended to increase but led to neither acceleration of bone turnover nor a decrease in bone mineral density.

Absorptiometry, Photon↗
PubMed2000

Presence of sonographically detectable parathyroid glands can predict resistance to oral pulsed-dose calcitriol treatment of secondary hyperparathyroidism.

Oral pulsed-dose calcitriol administration has been shown to be effective therapy for patients with secondary hyperparathyroidism. However, this effect is not consistently observed in the clinical setting. This study was undertaken to examine whether enlarged parathyroid glands can serve as a clinical marker that predicts the suppressive effect of calcitriol. Thirty-five patients undergoing chronic hemodialysis (HD) were examined (age, 51.9 +/- 14.9 years; duration of HD, 72.0 +/- 56.0 months). Based on the volume of parathyroid glands measured using an ultrasonographic scanner, patients were divided into two groups: 15 patients with undetectable parathyroid glands (ND group) and 20 patients with detectable parathyroid glands (D group; mean volume of parathyroid glands, 261. 9 +/- 347.5 mm(3)). No significant differences were found in serum ionized calcium (Ca(++)) or parathyroid hormone (PTH) levels before calcitriol administration between the two groups. For each patient, 8 microg of calcitriol was administered orally at the end of the HD session, and the changes in serum PTH levels were determined 44 hours after dosing. No significant differences were found between the two groups in serum Ca(++) levels. However, a significant decrease in serum PTH levels was observed in the ND group, whereas no significant changes were found in the D group. The results of the study show that the suppressive effect on PTH through calcitriol therapy was reduced in patients with detectable enlarged parathyroid glands. This may indicate that the size of parathyroid glands is one factor determining the therapeutic potential of pulsed-dose calcitriol administration for secondary hyperparathyroidism.

Administration, Oral↗
PubMed2000

Burkholderia kururiensis sp. nov., a trichloroethylene (TCE)-degrading bacterium isolated from an aquifer polluted with TCE.

A trichloroethylene (TCE)-degrading bacterium was isolated from an aquifer sample collected at a TCE-polluted site in Japan by enriching with phenol as sole carbon source. The isolate, designated strain KP23T, was a Gram-negative, oval-shaped micro-organism. A phylogenetic study based on 16S rRNA gene sequences indicated that strain KP23T should be placed in the genus Burkholderia. Cellular fatty acids of the strain were mainly composed of C16:0, cyclopropanic acid C17:0 and cyclopropanic acid C19:0. Strain KP23T also contained notable amounts of C13:1 and C17:1. The G + C content of total DNA was 64.8 mol%. Strain KP23T oxidized various sugars and sugar alcohols as sole carbon source such as galactose, glucose, mannose, maltose, glycerol, inositol and mannitol. Comparisons of its phenotypic and genotypic characteristics with other known species belonging to the genus Burkholderia suggested that strain KP23T represents a new species in the genus. The name Burkholderia kururiensis is proposed for this species, with strain KP23T as the type strain (= JCM 10599T).

Bacterial Typing Techniques↗
PubMed2000

Endothelial expression of selectins during endotoxin preconditioning.

Although bacterial endotoxins [lipopolysaccharide (LPS)] can confer tissue resistance to subsequent inflammatory insults, the mechanisms that underlie this LPS-preconditioning (LPS-PC) response remain poorly defined. The dual-radiolabeled monoclonal antibody technique was used to examine whether LPS-PC alters the upregulation (protein) of E- and P-selectins after subsequent LPS challenge. In the gut of wild-type (C57BL/6J) mice, LPS-PC was associated with a reduction in E- (66%) and P-selectin (33%) expression. A similar reduction in E-selectin expression was observed in mutant mice that were genetically deficient in either the endothelial or inducible isoform of nitric oxide synthase or that overexpressed the human gene for Cu/Zn superoxide dismutase. Severe combined immunodeficient mice, genetically devoid of lymphocytes, did exhibit partial inhibition of the LPS-PC response. We conclude that 1) LPS-PC can be demonstrated for E- and P-selectins in some vascular beds (e.g., gut), 2) the mechanism(s) underlying this blunted selectin response does not include a major role for either nitric oxide and superoxide, and 3) circulating lymphocytes may contribute to the LPS-PC response.

Animals↗
PubMed2000

Enhanced expression of osteopontin in human diabetic artery and analysis of its functional role in accelerated atherogenesis.

We have previously reported that high glucose stimulates osteopontin (OPN) expression through protein kinase C-dependent pathways as well as hexosamine pathways in cultured rat aortic smooth muscle cells. The finding prompted us to study in vivo expression of OPN in diabetes mellitus. In the present study, we found by immunohistochemistry that medial layers of the carotid arteries of streptozotocin-induced diabetic rats and the forearm arteries of diabetic patients stained positively for OPN antibodies, whereas the staining from arteries of control rats and nondiabetic patients was negative. We also found that OPN stimulated the migration and enhanced platelet-derived growth factor (PDGF)-mediated DNA synthesis of cultured rat aortic smooth muscle cells. OPN and PDGF synergistically activated focal adhesion kinase as well as extracellular signal-regulated kinase; this finding seems to explain the OPN-induced enhancement of PDGF-mediated DNA synthesis. Taken together, our present results raise a possibility that OPN plays a role in the development of diabetic vascular complications.

Adult↗
PubMed2000

DNA polymorphism analysis of a pure non-gestational choriocarcinoma of the ovary: case report.

A 45-year-old nulligravida woman died from carcinoma peritonitis with choriocarcinoma arising in the ovary. This tumor was resistant to chemotherapy after debulking surgery. DNA polymorphism analysis was useful in proving the choriocarcinoma to be non-gestational carcinoma. In this paper, the clinical course and DNA polymorphism findings are mainly discussed.

Antineoplastic Combined Chemotherapy Protocols↗
PubMed2000

Metastatic carcinoma in a transposed ovary after radical hysterectomy for a stage 1B cervical adenosquamous cell carcinoma. Case report.

A 41-year-old multigravida woman presented with a cervical stage 1b adenosquamous cell carcinoma with metastasis in a transposed ovary. Twenty-four months following a radical hysterectomy for cervical cancer a CT scan revealed a mass measuring 7x6x4 cm in size lateral to the ascending colon. The pathological diagnosis showed the mass to be metastatic adenocarcinoma in the transposed ovary which was considered to be adenocarcinoma from the previous cervical adenosquamous cell carcinoma. Thereafter, she was administered a combination of mitomycin C, etoposide and cisplatin (MEP) three times. One year following the completion of the chemotherapy she is still alive without any definitive recurrence. It is important to clarify whether or not ovarian transposition is safe and effective in helping surgeons determine whether or not to preserve the ovarian function for a young patient likely to undergo postoperative irradiation for early invasive cervical cancer. In the present report, we also review the current literature on this subject and discuss our findings.

Adult↗
PubMed1999

Comparison of p53, Ki-67, and CD44v6 expression between primary and matched metastatic lesions in ovarian cancer.

OBJECTIVE: Many studies have demonstrated that clinically evident tumor cells already carry multiple genetic alterations and further accumulation of genetic alteration causes tumor progression which plays a role in metastasis. Therefore, it could be expected that malignant potential in the metastatic site is more aggressive than that in the primary site. Using several immunohistochemical markers (p53, Ki-67, and CD44v6), we investigated an alteration of malignant potential. METHODS: We immunohistochemically examined expression of p53, Ki-67, and CD44 in primary and metastatic lesions of ovarian cancer. Fifty-six samples of primary lesions and matched metastatic sites from 56 patients with primary epithelial ovarian cancers were included in this study. RESULTS: In 16 cases (28%), the histological grade of the metastatic lesion increased. This difference was statistically significant (P = 0.0232). In 16 cases (28%), the expression of p53 increased in the metastatic lesions, in 5 pairs from negative to positive, whereas the case decrease in the metastatic lesions was only 1. This difference was statistically significant (P = 0.0046). There was no significant difference in Ki-67 labeling indices and expression of CD44v6 between the primary and matched metastatic lesions. The degree of p53 expression in the metastatic lesions significantly correlated with disease-free survival (P = 0.0482), whereas that in the primary lesions did not. Moreover, high p53 expression in the metastatic lesions significantly correlated with disease-free survival in multivariate analysis. CONCLUSIONS: The p53 expression in metastatic lesions may reflect an aggressive biologic behavior in ovarian cancer.

Adenocarcinoma↗
PubMed1999

Predicting pelvic lymph node metastasis in endometrial carcinoma.

BACKGROUND: To determine the possibility of individualizing the pelvic lymph node dissection in patients with endometrial cancer, the relationship between pelvic lymph node (PLN) metastasis and various prognostic factors was retrospectively investigated. METHODS: From 1979 to 1994, 175 patients with endometrial carcinoma were treated with either total or radical hysterectomy combined with a PLN dissection as initial therapy. The prognostic factors examined included clinical stage, patient age, histological grade, the microscopic degree of myometrial invasion (DMI), cervical invasion, adnexal metastasis, and macroscopic tumor diameter (TD). RESULTS: Of the 175 patients undergoing PLN dissection, 24 (14%) had PLN metastasis. An endometrial cancer with PLN metastasis had a significantly longer diameter than those without PLN metastasis. The frequency of PLN metastasis increased along with increases in tumor diameter. A logistic regression analysis revealed DMI and TD to be independently correlated with PLN metastasis. The formula based on the coefficients of TD and DMI obtained from the analysis also showed a good correlation, which allowed us to estimate the probability of patients having PLN metastasis. CONCLUSIONS: DMI and TD could accurately estimate the status of PLN in endometrial carcinoma patients.

Adenocarcinoma↗
PubMed1999

Roseateles depolymerans gen. nov., sp. nov., a new bacteriochlorophyll a-containing obligate aerobe belonging to the beta-subclass of the Proteobacteria.

Strains 61AT (T = type strain) and 61B2, the first bacteriochlorophyll (BChl) a-containing obligate aerobes to be classified in the beta-subclass of the Proteobacteria, were isolated from river water. The strains were originally isolated as degraders of poly(hexamethylene carbonate) (PHC). The organisms can utilize PHC and some other biodegradable plastics. The strains grow only under aerobic conditions. Good production of BChl a and caroterioid pigments is achieved on PHC agar plates and an equivalent production is observed under oligotrophic conditions on agar medium. Spectrometric results suggest that BChl a is present in light-harvesting complex I and the photochemical reaction centre. The main carotenoids are spirilloxanthin and its precursors. Analysis of the 16S rRNA gene sequence indicated that the phylogenetic positions of the two strains are similar to each other and that their closest relatives are the genera Rubrivivax, ideonella and Leptothrix with similarities of 96.3, 96.2 and 96.1%, respectively. The cells are motile, straight rods and contain poly-beta-hydroxybutyrate granules. Ubiquinone-8 is the predominant quinone. Vitamins are not required for growth. The G + C content of genomic DNA is 66.2-66.3 mol%. Genetic and phenotypic features suggest that the strains represent a new genus in the beta-subclass which is evenly distant from known genera. Consequently, the name Roseateles depolymerans gen. nov., sp. nov. is proposed for the strains; the type strain of Roseateles depolymerans is strain 61AT (= DSM 11813T).

Bacteria, Aerobic↗
PubMed1999

Soluble methane monooxygenase gene clusters from trichloroethylene-degrading Methylomonas sp. strains and detection of methanotrophs during in situ bioremediation.

The soluble MMO (sMMO) gene clusters from group I methanotrophs were characterized. An 8.1-kb KpnI fragment from Methylomonas sp. strain KSWIII and a 7.5-kb SalI fragment from Methylomonas sp. strain KSPIII which contained the sMMO gene clusters were cloned and sequenced. The sequences of these two fragments were almost identical. The sMMO gene clusters in the fragment consisted of six open reading frames which were 52 to 79% similar to the corresponding genes of previously described sMMO gene clusters of the group II and group X methanotrophs. The phylogenetic analysis of the predicted amino acid sequences of sMMO demonstrated that the sMMOs from these strains were closer to that from M. capsulatus Bath in the group X methanotrophs than to those from Methylosinus trichosporium OB3b and Methylocystis sp. strain M in the group II methanotrophs. Based on the sequence data of sMMO genes of our strains and other methanotrophs, we designed a new PCR primer to amplify sMMO gene fragments of all the known methanotrophs harboring the mmoX gene. The primer set was successfully used for detecting methanotrophs in the groundwater of trichloroethylene-contaminated sites during in situ-biostimulation treatments.

Amino Acid Sequence↗
PubMed1999

Time domain reflectometry: measurement of free water in normal lung and pulmonary edema.

The free water content of lung tissue was investigated by dielectric spectroscopy in normal lungs and in pulmonary edema induced by oleic acid in rats. The dielectric relaxation in a frequency range of 10(7) to 10(10) Hz was measured with the time domain reflectometry method at 25 degreesC. Three dielectric relaxation processes were analyzed for the lung tissue. A high-frequency process around 10 GHz was attributed to the orientation of free water molecules based on the relaxation time [log tauh (in s) = -11.03]. The dielectric strength (Delta epsilon) of this high-frequency peak (Delta epsilonh) should reflect the amount of free water in the tissue. Because the measured Delta epsilonh depended on the air content of the lung samples, the value of Delta epsilonh was corrected for the air content of each sample as determined by the point-counting method in the area where the time domain reflectometry data were obtained. The lungs of rats that received an injection of oleic acid had a significantly increased free water content [(Delta epsilonh of lung/Delta epsilon of pure water) x density of pure water] compared with that in the normal lung (0.76 vs. 0.59 g/cm3). These results indicate that free water occupies approximately 60% of the total volume of normal lung tissue and that there is an increase in free water in pulmonary edema.

Animals↗
PubMed1999

Long-term effects of dietary alpha-linolenic acid from perilla oil on serum fatty acids composition and on the risk factors of coronary heart disease in Japanese elderly subjects.

Although important roles of dietary n-3 fatty acids in the prevention of coronary heart disease (CHD) have been suggested, long-term effects of dietary alpha-linolenic acid (ALA, 18:3n-3) have not yet been established under controlled conditions. We tested whether a moderate increase of dietary ALA affects fatty acids composition in serum and the risk factors of CHD. Oxidized LDL (OxLDL) was directly measured by ELISA using antibody specific to OxLDL. By merely replacing soybean cooking oil (SO) with perilla oil (PO) (i.e., increasing 3 g/d of ALA), the n-6/n-3 ratio in the diet was changed from 4:1 to 1:1. Twenty Japanese elderly subjects were initially given a SO diet for at least 6 mo (baseline period), a PO diet for 10 mo (intervention period), and then returned to the previous SO diet (washout period). ALA in the total serum lipid increased from 0.8 to 1.6% after 3 mo on the PO diet, but EPA and DHA increased in a later time, at 10 mo after the PO diet, from 2.5 to 3.6% and 5.3 to 6.4%, respectively (p<0.05), and then returned to baseline in the washout period. In spite of increases of serum n-3 fatty acids, the OxLDL concentration did not change significantly when given the PO diet. Body weight, total serum cholesterol, triacylglycerol, glucose, insulin and HbA1c concentrations, platelet count and aggregation function, prothrombin time, partial thromboplastin time, fibrinogen and PAI-1 concentration, and other routine blood analysis did not change significantly when given the PO diet. These data indicate that, even in elderly subjects, a 3 g/d increase of dietary ALA could increase serum EPA and DHA in 10 mo without any major adverse effects.

Aged↗
PubMed1999

[A study of association between lean body mass and serum insulin-like growth factor-1 in continuous ambulatory peritoneal dialysis patients].

Malnutrition is one of the major issues associated with high mortality and morbidity in chronic dialysis patients. Several methods to evaluate the nutritional status of these patients have been attempted for example anthropometric measurement and biochemical parameters. Recently, it was reported that insulin-like growth factor-1 (IGF-1) has been valuable for estimating nutritional status. In this study, we measured lean body mass (LBM) by dual energy X-ray absorptiometry (DXA), IGF-1 and other biochemical parameters in 35 patients on CAPD. Two years later, the second measurement of LBM was performed, and we assessed the percent changes of LBM and biochemical parameters. There was negative correlation between the percent changes of LBM and the duration of CAPD. In patients treated with CAPD for less than 36 months (group I) LBM increased, however, it decreased significantly in those treated for more than 36 months (group II). On the other hand, in group I there was a positive correlation between the percent changes of LBM and IGF-1. In group II there was no correlation between the percent changes of LBM and any other biochemical parameters. It could be concluded that IGF-1 is one of the predisposing factors for improving LBM of patients on CAPD for a limited duration.

Absorptiometry, Photon↗
PubMed1999

Histopathological factors influencing pelvic lymph node metastases in two or more sites in patients with cervical carcinoma undergoing radical hysterectomy.

BACKGROUND: Lymph node metastasis has been one of the strongest prognostic factors in patients with cervical cancer. In order to select patients with high risk for recurrence, a relationship between status of lymph node and other histopathological parameters was investigated in the patients treated with radical hysterectomy with pelvic lymph adnectomy. METHODS: Of 483 patients undergoing radical hysterectomy with pelvic lymph adnectomy, 309 had stage Ib disease, 62 stage IIa, and 112 stage IIb. RESULTS: Pelvic lymph node metastasis(PLNM) was positive in 98 patients (20%). Of those positive patients, 51(56%) had metastasis in one site, 25 (26%) in two sites, and 22 (22%) in three or more sites. There was a significant difference in survival between patients with metastasis in one or no sites and those in two or more sites (p<0.0001). There was a relationship between PLNM in more than two sites and histological parameters such as histologic subtype, longitudinal diameter of cervical lesion, degree of stromal invasion, depth of stromal invasion, lymph-vascular space invasion, parametrial invasion, and corpus invasion. All of these parameters except for histologic subtype were significantly correlated with the number of positive lymph node sites. Multivariate analysis revealed that among these parameters, longitudinal diameter of the cervical lesion, parametrial invasion, and lymph-vascular space invasion were independently significantly correlated with PLNM in two or more sites. CONCLUSIONS: From these results, patients having these three histopathological parameters could be considered as those with extensive disease distribution.

Adenocarcinoma↗
PubMed1998

Identification of persistent trophoblastic diseases based on a human chorionic gonadotropin regression curve by means of a stepwise piecewise linear regression analysis after the evacuation of uneventful moles.

Among the 191 patients with complete hydatidiform moles who were diagnosed and treated at Kyushu University Hospital from 1982 until 1996, 167 patients were diagnosed with uneventful moles retrospectively. The serial beta human chorionic gonadotropin (hCG) values in the 167 patients with uneventful moles were analyzed by a stepwise piecewise linear regression analysis in order to establish a normal regression curve of a human chorionic gonadotropin after a molar pregnancy. This normal regression curve is considered to be excellent regarding sensitivity (24/24-100%) and to be equivalent to the identification based on a plateau or a rise regarding specificity (156/167-93.4%). To distinguish patients with persistent trophoblastic disease (PTD) from uneventful moles, this normal curve is thus considered to be accurate since the accuracy was 180/191 (94. 2%). The weeks exceeding the normal regression curve in 24 PTD patients were 5.04 +/- 3.85 weeks and were also earlier than the weeks based on a plateau or a rise (P = 0.01). Within 7 weeks after evacuation, in 21/24 (87.5%) of the PTD cases, the beta-hCG values exceeded the normal range, while in only 14/24 (58.3%) the beta-hCG showed a change in the shape of a plateau or a rise. In addition, in 19/24 (79.2%) of the PTD patients, the time exceeding the normal range was shorter than the time exhibiting a plateau or a rise in the beta-hCG change. The above findings thus led us to conclude that this normal regression curve was useful for discriminating PTD from uneventful moles more precisely and more quickly than by identification based on a plateau or a rise.

Chorionic Gonadotropin↗