PubMed Health⌕ Search

Biomedical subjects

S Takeyama

Publications and source records attributed to S Takeyama.

At least 19 recordsLinked to original sources
PubMed1999

Effect of extracellular calcium concentrations on osteoclast differentiation in vitro.

We have been researching with the purpose of understanding the hard organization mineralization-suppression mechanism under a low calcium environment. So far, we have discerned clearly that the femur of an incubated newborn rat under a low calcium environment will develop bone formation dyscrasia such as hypertrophy of the caput. In this experiment, MC3T3-E1 (E1) cells, which are osteoblast-like cells, and mouse bone marrow were incubated in a coculture system under a low calcium environment and manifestation of osteoblast cells and their ability to resorb were examined. The results suggested that as the calcium concentration in the medium decreased manifestation of osteoclast cells increased, and as the degree of mineralization of E1 cells advanced, the number of manifestation of osteoblast cells decreased. We, therefore, report that there is a possibility that extracellular calcium concentrations involve the process of differentiation of bone marrow cells into osteoblast cells.

3T3 Cells↗
PubMed1998

Isolation and characterization of di- and tri-mannosyl-cyclomaltoheptaoses (beta-cyclodextrins) produced by reverse action of alpha-mannosidase from jack bean.

Di- and tri-mannosyl-cyclomaltoheptaoses (beta-cyclodextrins, beta CDs), which were synthesized together with monomannosyl-beta CD in a large-scale production by reverse action of alpha-mannosidase from jack bean, were isolated and purified by HPLC. The structures of seven isomers of di-mannosyl-beta CD and six isomers of tri-mannosyl-beta CD were elucidated by FABMS and NMR spectroscopy, and by enzymatic methods.

Chromatography, High Pressure Liquid↗
PubMed1998

[Clinical study on fluconazole (FLCZ) in the treatment of primary pulmonary cryptococcosis].

We treated two cases of primary pulmonary cryptococcosis with fluconazole (FLCZ), the clinical usefulness of FLCZ was evaluated. FLCZ was administered orally in doses of 300 mg daily for about six months. Concentrations of FLCZ were measured in the serum of the two cases and in the bronchoalveolar lavage (BAL) fluid in one case. The following results were obtained: 1. Clinical cures were obtained in the two cases. 2. The serum levels of FLCZ was 15.1 microliters/ml, 13.6 micrograms/ml two hours after administration of 100 mg in case 1, that of levels were 11.1 micrograms/ml, 8.9 micrograms/ml one hour and 4.5 hours, respectively, after administration of 100 mg in case 2. BAL was performed 4.5 hours after administration of 100 mg in case 2, the BAL fluid level of FLCZ was 0.7 microgram/ml. 3. The minimal inhibitory concentration of FLCZ against one strain obtained from the cytology brush in case 1 was 4.0 micrograms/ml. 4. The cryptococcal antigen titer decreased with the improvement of clinical signs and the resolution of chest X-ray abnormalities within about six months, and there was no relapse. From these results, we consider that FLCZ is a useful antifungal agent for primary pulmonary cryptococcosis, and we therefore recommend a six month treatment.

Adult↗
PubMed1998

[Clinical study on sparfloxacin (SPFX) in the treatment of mycoplasmal pneumonia and penetration of SPFX to the pneumonic lesion].

We treated nine patients of mycoplasmal pneumonia with sparfloxacin (SPFX) the clinical efficacy, safety and usefulness of SPFX were evaluated. SPFX was administered orally at doses of 200 or 300 mg once daily, and we performed bronchoalveolar lavage (BAL) examinations in five patients. BAL was performed 5 hours after oral administration of 100 mg in one case, 19 hours after oral administration of 200 mg in four cases. Concentrations of SPFX and alubumine were measured in serum and in BALF (bronchoalveolar lavage fluid). The following results were obtained. 1. Nine patients were evaluated; eight patients judged as Good, one patient as Excellent. 2. The serum and BALF levels of SPFX was 0.79 microgram/ml, 0.107 microgram/ml 5 hours after single oral administration of 100 mg in one case and 19 hours after oral administration of 200 mg in four cases, those of levels of SPFX were 0.835 +/- 0.274 microgram/ml and 0.081 +/- 0.033 microgram/ml, respectively. 3. The ratio of SPFX/albumin in BALF was significantly higher than in the serum. From these results, we consider that SPFX is a useful antimicrobial agent for mycoplasmal pneumonia.

Administration, Oral↗
PubMed1998

Augmentation of sinecomitant immunity in mice by gamma-(9H-purine-6-yl)thiomethyl L-glutamate (6-MPG), a water-soluble derivative of 6-mercaptopurine.

Effects of the administration of gamma-(9H-purine-6-yl)thiomethyl L-glutamate (6-MPG), a water-soluble derivative of 6-mercaptopurine, on concomitant and sinecomitant immunity against the implanted MethA tumor were studied in BALB/c mice. In the concomitant immunity experiments, mice were intradermally inoculated with 1x10(5) MethA cells at the right inguinal region on day 0. In sinecomitant immunity experiments, mice were similarly inoculated on day -21, and the grown tumor was excised on day -11. Both the tumor-bearing and tumor-ectomized animals were re-inoculated with 3x10(6) MethA cells intradermally at the left inguinal region on day 10. Administration of 6-MPG (100 mg/kg, i.p.) on days 3 through 7 significantly inhibited growth of the re-inoculated tumor in both series of experiments. Cyclophosphamide, adriamycin, mitomycin C and cis-diamminedichloroplatinum (II) had no significant effect on the growth of the re-inoculated tumor in the tumor-ectomized mice. Spleen cells harvested from the 6-MPG-treated tumor-ectomized mice showed a strong tumor-neutralizing activity (Winn assay).

Animals↗
PubMed1998

Augmentation of tumor immunity in mice by intralesional injection of vitamin A.

We investigated the antitumor effect of vitamin A(VA) using the double grafted tumor technique to examine whether VA administered into a primary tumor (intralesionally or i.l.) accelerates antitumor immune reactions so that growth of the secondary tumor may be more effectively inhibited than by other systemic administration routes. In the double grafted tumor system, where BALB/c mice were inoculated with MethA fibrosarcoma cells into the right inguinal region (1 x 10[6] cells) on day 0 and later into the left (3 x 10[6] cells) on day 10, the injection of VA at a dose of 1000 IU/mouse i.l., s.c., i.p., and i.v. on days 3 through 7 inhibited the growth of the secondary tumor to the same extent, while VA at the i.l. dose of 100 IU/mouse into the primary tumor inhibited more effectively than by any other administration route. VA did not inhibit the secondary MethA growth in BALB/c (nu/nu) mice. The spleen cells taken from VA-treated tumor-bearing mice prevented the growth of MethA tumors in naive BALB/c mice when given as a mixture with the MethA inoculum (the Winn assay). The delayed-type hypersensitivity (DTH) response to methylated bovine serum albumin (MBSA) antigen was augmented when VA (1000 IU) was injected at the site of the antigen injection. These results suggest that the direct interaction of VA with the tumor cells may be necessary for the tumor immunity-potentiating effect of VA, and that T-lymphocyte-mediated tumor immunity is involved in the anti-tumor effect of VA. The antitumor mechanism of VA seems to involve retinoid receptors, because the benzoic acid derivative Am80, which has been reported to exert retinoidal activity by binding to specific retinoid receptors, also showed activity.

Animals↗
PubMed1997

Study on the mechanism of immunopotentiating antitumor effect of 6-MPG, a water-soluble derivative of 6-mercaptopurine.

We investigated possible mechanisms of the antitumor action of gamma-(9H-purine-6-yl) thiomethyl L-glutamate (6-MPG), a water-soluble derivative of 6-MP. In the double grafted tumor system, BALB/c mice were inoculated intradermally with 10(6) cells of MethA fibrosarcoma at the right inguinal region on day 0 (the primary tumor) and later with 3 x 10(6) cells at the left on day 10 (the secondary tumor). Intraperitoneal administration of 6-MPG at a dose of 100 mg/kg/day from day 3 through 7 completely prevented growth of the secondary tumor. 6-MPG showed no effect on growth of colon 26 adenocarcinoma cells inoculated in place of the secondary MethA cells (antigen specificity). 6-MPG did not inhibit the secondary MethA growth in the BALB/c (nu/nu) mouse. The inhibitory effect of 6-MPG on the secondary tumor growth was diminished by prior treatment of the primed animals with cyclosporin A and anti-Thy antibody. Spleen cells from the tumor-bearing mice treated with 6-MPG showed a tumor-neutralizing activity (Winn assay). Treatment of the spleen cells with anti-CD8 antibody plus complement diminished the tumor-neutralizing effect but that with anti-CD4 antibody plus complement did not, indicating that CD8-positive cells are responsible for potentiation of the tumor immunity. These results suggest that the antitumor effect of 6-MPG against the secondary tumor is elicited by augmenting tumor specific T-cell production.

Adenocarcinoma↗
PubMed1997

[Thymic cyst resembling a bronchogenic cyst].

Bronchogenic cysts are common cystic lesions in the mediastinum. Most are located in the middle or posterior ares of the mediastinum, especially around the carina. We encountered a patient with a mass in the superior and anterior areas of the mediastinum, where bronchogenic cysts are not usually found. The mass was therefore, thought to be a thymic cyst. The cyst was located just behind the sternum and in front of the left brachio-cephalic vein, and was 5.5 x 3.5 x 1.2 cm. It originated in the upper and median part of the thymus, and was not attached to the respiratory tract. Histological examination showed ciliacted epithelium and a layer of smooth muscle in the wall of the cyst. The cyst contained viscid, yellowish, turbid fluid. Preoperative computed tomography and magnetic resonance imaging showed findings characteristic of bronchogenic cysts, except for the location. We know of no previous reported case of a thymic cyst resembling a bronchogenic cyst.

Bronchogenic Cyst↗
PubMed1997

[Effect on 5'-deoxy-5-fluorouridine (5'-DFUR) of pyrimidine nucleoside phosphorylase (PyNPase), matrix metalloprotease and serum IAP values. Hokuriku Colorectal Cancer Chemotherapy Study Group].

PyNPase activity, MMPs activity and serum IAP values were measured in tumor tissues from colorectal cancer patients who had been divided into two groups, one given preoperative 5'-DFUR and the controls. PyNPase activity of the preoperative administration group was approximately equivalent to that of the controls. In the control group, correlations were assessed between PyNPase activity and activities of MMP1 and MMP3. To assess the effect of 5'-DFUR on the activity of MMPs, we divided patients into two groups, a high and a low PyNPase activity group. Although there was no correlation with MMPs activity of the preoperative administration group and the control group in the low PyNPase activity group, the activities of MMP1 and MMP9 of the control group were significantly higher in the high PyNPase activity group. Moreover, the serum IAP value of the administration group was significantly lower than that of the control group. These results indicated that PyNPase activity was thus suggested to be somehow related to MMPs activity and serum IAP values.

Adult↗
PubMed1996

Adhesive protein cDNA sequence of the mussel Mytilus coruscus and its evolutionary implications.

cDNA encoding the adhesive protein of the mussel Mytilus coruscus (Mcfp1) was isolated. The coding region encoded 848 amino acids (a.a.) comprising the 20-a.a. signal peptide, the 21-a.a. nonrepetitive linker, and the 805-a.a. repetitive domain. Although the first 204 nucleotides and the 3'-untranslated region of Mcfp1 cDNA were homologous to corresponding parts of M. galloprovincialis adhesive protein (Mgfp1) cDNA, the other parts diverged. The representative repeat motif of the repetitive domain, YKPK(I/P)(S/T)YPP(T/S), was similar but slightly different from the repeat motif of Mgfp1. The codon usage patterns for the same amino acids were different in different positions of the decapeptide motif. Almost identical nucleotide sequences encoding the two to 13 repeats appeared several times in the repetitive region, which suggests that the adhesive protein genes of mussels have evolved through the duplication of these repeat units.

Amino Acid Sequence↗
PubMed1996

Augmentation of tumor immunity by 6-MPG, a water-soluble derivative of 6-mercaptopurine, in mice.

Inhibitory effects on some immunological responses and MethA fibrosarcoma in the double grafted tumor system in mice were compared between 6-mercaptopurine (6-MP) and its novel water-soluble derivative, gamma-(9H-purine-6-yl)thiomethyl L-glutamate (6-MPG). The dose-dependent inhibitory effects by 6-MPG on the hemagglutinin response to SRBC, DTH reaction to MBSA, contact sensitivity to oxazolone, GVH response and growth of the primary tumor were 3-10 times weaker than those by 6-MP, probably reflecting the difference in their cytotoxicities antimetabolites. However, the two drugs were nearly equipotent in reproducing inhibition of the secondary tumor growth, which is a host-mediated immunological response to tumor antigen as shown by its dependency on the primary inoculation with 1 x 10(4) or more MethA cells and by the production of anti-tumor splenocytes in tumor-bearing animals (the Winn assay). Thus, 6-MPG may point to the direction of derivatization towards anti-tumor immunopotentiators with an improved therapeutic index.

Adjuvants, Immunologic↗
PubMed1996

Biosynthesis of the acetylenic compounds in cultured cells of Asparagus officinalis from D- and 13C-labelled phenylalanines.

Studies on the biosynthetic pathway of acetylenic compounds, 4-[5-(4-methoxyphenoxy)-3-penten-1-ynyl]phenol and its related compounds, in cultured cells of Asparagus officinalis L. (Liliaceae) revealed that all of the 17 carbon atoms in their skeletons are supplied by phenylalanine. It is also concluded that p-substituted phenylacetylenic moieties (the C6-C2 unit) in these compounds are derived from C6-C3 shikimate pathway metabolites via phenylalanine. As a working hypothesis concerning the C6-O-C3 unit formation, a spirotetrahydrofuran type intermediate is predicted.

Acetylene↗
PubMed1995

A case of macrocystic serous cystadenoma of the pancreas.

A case of macrocystic serous cystadenoma of the pancreas is presented, and literature is reviewed. A 35-yr-old woman presented with mild upper abdominal pain. Abdominal ultrasonography and an abdominal computed tomography revealed a multiloculated and calcified cyst in the body of the pancreas. A T1-weighted image, using magnetic resonance imaging, revealed a low-intensity multiloculated, pancreatic mass. In contrast, T2-imaging of the tumor showed a high-intensity mass. Endoscopic retrograde cholangiopancreatography showed no contact between the main pancreatic duct and the tumor. The preoperative diagnosis was a mucinous cystic neoplasm. Tumor enucleation was performed. Subsequent microscopic examination of this tumor suggested the diagnosis of a macrocystic serous cystadenoma of the pancreas.

Adult↗
PubMed1995

[A case of myelodysplastic syndrome who died of septic pulmonary embolism].

A case of myelodysplastic syndrome (MDS) complicated by septic pulmonary embolism is reported. A 61-year-old female who had been followed for refractory anemia with excess of blasts suddenly died of acute respiratory failure. An autopsy revealed massive pulmonary emboli with gram-positive cocci gathered in the emboli and alveolar spaces. Staphylococcus aureus was also detected through a blood culture from the right atrium. We speculate that pulmonary embolism was the result of septicemia induced by the immunosuppressive condition associated with MDS.

Fatal Outcome↗
PubMed1995

Biosynthesis of acetylenic compounds in cultured cells of Asparagus officinalis from [1-13C]- and [U-13C] Glucose.

The biosynthetic pathway of phenolics with an acetylenic group, 4-[5-(4-methoxyphenoxy)-3-penten-1-ynyl]phenol (1) and its related compounds, isolated from suspension-cultured cells of Asparagus officinalis L. (Liliaceae), was studied in feeding experiments using [1-13C]- and [U-13C] glucose. Analyses of the 13C-NMR spectra of the methyl ether and acetate of the 13C-labelled species of 1 indicated that the aromatic rings at both ends of the molecule are formed from shikimic acid. It was also assumed that the acetylenic carbons in the C5 chain could be incorporated together with its adjacent aromatic ring through any phenethyl class compound derived from phenylpropanoids, and the propenylene carbon through glycolysis metabolites with C3 carbon units.

Acetylation↗