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Biomedical subjects

M Taguchi

Publications and source records attributed to M Taguchi.

At least 91 records · Page 5Linked to original sources
PubMed1992

Direct effect of endothelin-1 on the granuloma cells of the porcine ovary.

Specific binding sites for endothelin-1 (ET-1), a novel potent vasoconstrictor peptide, as well as the effects of ET-1 on cytosolic free Ca2+ concentration ([Ca2+]i), intracellular total inositol phosphate (IP) generation and steroidogenesis were studied in cultured porcine granulosa cells. Scatchard analysis of a binding study using 125I-labelled ET-1 indicated the presence of a single class of high-affinity binding sites with almost equal affinity for ET-1 and ET-3: the apparent dissociation constant was 0.59 nmol/l and the maximal binding capacity was 1.84 pmol/mg protein. Affinity-labelling of 125I-labelled ET-1 to the membranes using disuccinimidyl tartarate as a cross-linker revealed one major and one minor band with the apparent molecular weights of 32 kDa and 49 kDa respectively. ET-1 dose-dependently (1-100 nmol/l) induced rapid and transient increases in [Ca2+]i in fura-2-labelled cells. ET-1 also dose-dependently stimulated total IPs in cells prelabelled with myo-[3H]inositol. ET-1 had a slight stimulatory effect on the secretion of progesterone but not of oestradiol from porcine granulosa cells. The present data clearly demonstrate the presence of a non-selective ET receptor (ETB) in porcine granulosa cells coupled with phosphoinositide hydrolysis and [Ca2+]i mobilization, and suggest that ET-1 may play some role in the production of progesterone by porcine granulosa cells.

Animals↗
PubMed1992

Characterization of mineral-binding 40-kDa glycoprotein extracted from young adult rabbit alveolar bone.

A forty-kilodalton (40-kDa) protein was extracted from alveolar bone of young adult rabbit with 0.5 M EDTA after extraction with 4 M GuHCl, and purified by gel-filtration, anion-exchange and hydroxyapatite columns using a high-pressure liquid chromatography system under denaturing conditions. The purified 40-kDa protein was not susceptible to bacterial collagenase and thrombin, but was cleaved by cyanogen bromide. The protein was stained blue with Stains-all. Among various lectins, concanavalin A and lentil lectin agglutinin bound to this protein, but peanut agglutinin, Ricinus communis agglutinin, phytohemagglutinin-E and wheatgerm lectin agglutinin did not. Lectin binding assays showed that the protein is a glycoprotein containing large amounts of mannose and/or glucose residues, but is not a fragment of proteoglycan. The amino acid composition of the protein shows a characteristically high content of acidic amino acids. Therefore, the mineral-binding 40-kDa glycoprotein is considered to be osteonectin/secreted protein acidic and rich in cysteine (SPARC), in terms of similarities to bovine and porcine osteonectins with regard to molecular weight and contents of glycoses and amino acids.

Alveolar Process↗
PubMed1992

[The effects of diazepam premedication upon atropine-induced hemodynamic changes].

Positive or negative chronotropic effects of atropine and their magnitude are known to be determined primarily by patient's age, atropine dose, anesthetic agents or techniques, and preanesthetic medication. The aim of the present study is to investigate the effects of oral diazepam upon the hemodynamic responses to intravenous atropine in awake patients. Diazepam group (n = 26) received oral diazepam, 10 mg, whereas control group (n = 20) received no premedication. The direction and magnitude of heart rate and blood pressure responses to atropine were similar between the two groups. Heart rate significantly decreased from baseline values following atropine, 2.5 micrograms.kg-1, returned to baseline values following cumulative atropine doses, 5 micrograms.kg-1, then significantly increased from baseline values following cumulative atropine dose, 10 micrograms.kg-1 in both groups. Mean blood pressure significantly decreased from baseline values following cumulative atropine dose, 2.5 and 5 micrograms.kg-1, and returned to baseline following cumulative atropine dose, 10 micrograms.kg-1, in both groups. It is concluded that oral diazepam, 10 mg, as a premedicant does not alter the hemodynamic responses to intravenous atropine in humans.

Administration, Oral↗
PubMed1992

[A case of pulmonary blastoma].

A 45-year-old male with pulmonary blastoma was described. The patient suffered from headache and gait disturbance, and was diagnosed metastatic brain tumor. The histopathology of the removed tumor indicated metastasis from pulmonary blastoma. The pulmonary tumor, which had been detected on the chest x-ray film but misdiagnosed tuberculous lesion, was subsequently diagnosed pulmonary blastoma by TBLB. The patient underwent left upper lobectomy with mediastinal lymph node dissection, but died 12 months after the operation. To our knowledge, only 54 cases with pulmonary blastoma have hitherto been reported in the Japanese literature.

Brain Neoplasms↗
PubMed1991

Argon laser-assisted anastomoses in medium-size vessels: one-year follow-up.

Laser-assisted anastomosis of medium-size vessels can be performed with satisfactory short-term patency. This study was undertaken to evaluate patency and structural integrity up to 1 year. An argon laser was used to make bilateral femoral arteriovenous anastomoses in 12 dogs compared to conventional suture method in another 8 dogs. These anastomoses were evaluated for patency and aneurysm formation at 1 hour; 1, 2, 4, and 8 weeks; and 12 months after surgery. All anastomotic sites were patent and without aneurysmal change or luminal narrowing at all harvesting intervals. Histologic examination revealed that within 1 month laser anastomotic sites were almost completely healed and without intimal hyperplasia. In suture anastomoses, foreign-body reaction remained evident up to 1 year. Use of the argon laser for medium size vessel anastomoses resulted in excellent patency without aneurysm formation or intimal hyperplasia even in the long term. These data suggest promising clinical applications.

Anastomosis, Surgical↗
PubMed1991

2-Oxo-1,3-dioxoles as specific substrates for measurement of arylesterase activity.

Various 4-arylthiomethyl-2-oxo-1,3-dioxole derivatives IIIa-o were synthesized. Their hydrolysis rates by arylesterase (EC 3.1.1.2) and cholinesterase (EC 3.1.1.8) in human serum were evaluated. Some of them were not hydrolyzed by cholinesterase, but were hydrolyzed easily by arylesterase. Among the substrates, sodium 4-((5-methyl-2-oxo-1,3-dioxol-4-yl)methylthio)benzenesulfonate (IIIg) was selected for its substrate reactivity toward arylesterase and its good water solubility. In addition, neither aliesterase (EC 3.1.1.1), acetylesterase (EC 3.1.1.6) nor cholesterol esterase (EC 3.1.1.13) hydrolyzed the compound. IIIg is thus concluded to be a specific substrate for arylesterase. Our assay system for serum arylesterase using IIIg can be readily applied to an automatic analyzer in the diagnosis of liver cirrhosis.

Carboxylic Ester Hydrolases↗
PubMed1991

[An improved purification of human placental transferrin receptor and biochemical properties of the receptor].

An improved method for the purification of human placental transferrin receptor (Tf-R) was developed. Fresh human placenta was homogenized in cold acetone and the acetone powder was prepared. After the acetone powder had been washed with HEPES buffer, the insoluble proteins containing Tf-R were separated by centrifugation and dissolved in Emulgen 109P-containing buffer. Tf-R was collected by affinity binding to Tf-Sepharose and extracted by consecutive treatment with 4 different kinds of buffers. Tf-R was eluted by buffer C (2 M KCl) and buffer D (0.5 M NaSCN). Tf-R was characterized as a 90-kDa monomer on gradient SDS-PAGE (4-20%) in the presence of 2-mercaptoethanol. Though there were several minor bands of 180- and above 205-kDa, all these bands were confirmed as Tf-R by Western blotting using an anti-Tf-R monoclonal antibody (OKT 9). The apparent molecular weights, measured by HPLC using a TSK-G 3,000 SW column, demonstrated that Tf-Rs eluted with buffer C were approximately 370-, 500- and above 500-kDa, but only a peak of above 500-kDa was found in Tf-R eluted with buffer D. Although the polymers of Tf-R with molecular weight of above 500-kDa were resistant to trypsin digestion, the Tf-R of 370-kDa was resistant to the enzyme only when it conjugated to the diferric Tf. The stability of the polymers of above 500-kDa to trypsin digestion suggested an advantage for the repeated use of Tf-R in the endocytosis of diferric Tf, which was performed by the translocation of Tf-R between cell surface and intracellular vesicles.

Chromatography, High Pressure Liquid↗
PubMed1991

Enzymatic regulation of glycolysis and gluconeogenesis in rabbit periodontal ligament under various physiological pH conditions.

Optimal concentrations of the essential components for analyzing the activity of each enzyme associated with glycolysis and gluconeogenesis in rabbit periodontal ligament were examined, and enzyme assay systems for 15 enzymes including 22 reactions were established using triethanolamine buffer. Specific activities of all the enzymes, except for the gluconeogenic reaction of phosphoglycerate kinase, were systematically evaluated using the optimum buffer for each enzyme, since the activity of each enzyme varied depending on the buffer used. For glycolysis, the activity levels of hexokinase and 6-phosphofructokinase were very low, and consequently these enzyme reactions were inferred to be the rate-limiting steps. For gluconeogenesis, fructose 1,6-bisphosphatase and aldolase activities were extremely low, and the activities of glucose 6-phosphatase, phosphoenolpyruvate carboxykinase and pyruvate carboxylase were undetectable. These results suggest that the periodontal ligament may have no gluconeogenesis capability. With a rise in pH, the activities of the key enzymes of glycolysis gradually increased, and a specific "crossover" point was found between the activities of glyceraldehyde-phosphate dehydrogenase and phosphoglyceromutase. In addition, the activity of fructose 1,6-bisphosphatase, one of the key enzymes of gluconeogenesis, was markedly increased with a rise in pH, although pH changes had no effect on aldolase activity. Consequently, alkaline pH appeared to result in overall stimulation of glycolysis.

Animals↗
PubMed1991

[Effects of clonidine premedication upon hemodynamic changes associated with laryngoscopy and tracheal intubation].

The authors studied 30 patients undergoing general anesthesia in order to evaluate whether oral clonidine premedication could attenuate the hemodynamic changes associated with laryngoscopy and tracheal intubation. Patients were randomly assigned to one of two groups; clonidine group (n = 15) who received oral clonidine of approximately 5 micrograms.kg-1, or control group (n = 15) who received no clonidine. The magnitude of increases in mean blood pressure from baseline values following laryngoscopy and tracheal intubation in the clonidine group was significantly smaller as compared with that in the control group (20 +/- 12 vs. 31 +/- 14 mmHg, mean +/- SD, P less than 0.05). There was also a significant difference between the two groups in the incidence of systolic blood pressure increases above 180 mmHg following laryngoscopy and tracheal intubation (0% vs. 26%, P less than 0.05). However, no significant difference was noted between the two groups in the heart rate responses to laryngoscopy and tracheal intubation. It is concluded that oral clonidine of 5 micrograms.kg-1 as a preanesthetic medication could attenuate the pressor responses associated with laryngoscopy and tracheal intubation.

Administration, Oral↗
PubMed1991

[The effects of insulin-like growth factor-I (IGF-I) and IGF-II on prolactin (PRL) release from human decidua and amniotic fluid circulation].

It has been reported that insulin-like growth factor (IGF) may play an important role in the feto-placental environment during pregnancy. The present study was undertaken to investigate the effect of IGF-I and IGF-II on prolactin (PRL) release from human decidual cells in vitro and in vivo. The human decidua in early pregnancy was obtained by D & C, and was enzymatically dispersed into a monocellular suspension. Monolayer cultures of these cells were exposed for 96 hours to either control media or medium supplemented with IGF-I and IGF-II. PRL levels in the media were measured by EIA. Five days after dispersion, the intracellular calcium concentration [( Ca]2+i) in cultured decidual cells was measured by the Fura-2 fluorescence method with a Spectrofluorometer. PRL and IGF-I levels in amniotic fluid of 2nd trimester and term pregnancy were measured by RIA for in vivo study. In an in vitro study, IGF-I increased PRL release from decidual cells significantly during a 96 hour culture. However, IGF-II did not enhance this PRL release. IGF-I stimulation had no effect on [Ca]2+i. In an in vivo study, amniotic fluid IGF-I levels in the 2nd trimester (139.8 +/- 28.1 ng/ml) were significantly higher than those in term pregnancy (46.4 +/- 14.2 ng/ml), and a significant positive correlation (r = 0.852, p less than 0.001) was observed between IGF-I and PRL levels in the amniotic fluid. The present in vivo and in vitro studies indicated that IGF-I plays an important role in PRL release from decidua into amniotic fluid.(ABSTRACT TRUNCATED AT 250 WORDS)

Amniotic Fluid↗
PubMed1991

[Levels of endothelin-1 in maternal and cord plasma during pregnancy and delivery].

In order to elucidate the possible involvement of endothelin-1 (ET-1) in the development of the feto-placental unit, plasma concentrations of immunoreactive ET-1 during pregnancy and delivery were measured in the current study. Forty-four pregnant women (8 in the 1st trimester, 8 in the 2nd trimester, 12 in the 3rd trimester and 16 at delivery), 6 at 1 month postpartum and 14 non-pregnant women volunteered to participate in this study. Plasma levels of immunoreactive ET-1 in all subjects were measured by specific radioimmunoassay. Plasma cortisol, prolactin and oxytocin levels during delivery were also measured by RIA. Although plasma ET-1 levels did not change during the 1st (1.3 +/- 0.4 pg/ml, mean +/- S.E.M., n = 8) or 2nd (1.7 +/- 0.3 pg/ml, n = 8) trimester, they were significantly (p less than 0.05) higher in the 3rd trimester (2.6 +/- 0.3 pg/ml, n = 12) than those of the non-pregnant controls (1.7 +/- 0.3 pg/ml, n = 14) and returned to the control levels within 1 month post-partum (1.8 +/- 0.1 pg/ml, n = 6). Maternal ET-1 levels before labor onset (2.3 +/- 0.4 pg/ml, n = 16), at delivery (3.0 +/- 0.7 pg/ml) and 24 hours post-partum (2.7 +/- 0.5 pg/ml) showed no significant differences among them. On the other hand, ET-1 levels in cord plasma (7.0 +/- 1.2 pg/ml) were significantly higher (p less than 0.05) than those in maternal plasma. Furthermore, there were no significant correlations between plasma ET-1 levels and those of other hormones (cortisol, prolactin and oxytocin) during delivery. From these results, we concluded that maternal plasma ET-1 levels significantly increased in the last trimester and returned to non-pregnant levels within one month post-partum.

Adult↗
PubMed1990

[Physical effects of treatment for childhood malignant solid tumors--a data to develop an assessment method of quality of life].

To understand the effects of treatment of childhood malignant solid tumors on the children, thirty-two survivors were examined by a questionnaire method. The play-performance scale for children (PPSC) was used to evaluate performance status in patients under 15 years of age. Ratings over 80 were obtained in 25 of 26 children (96.2%) and mean score was 94.2 +/- 8.4. Although the results of PPSC were satisfactory, several problems concerning patient's conditions including dental caries, short stature, radiation induced deformity and surgical scar, and physical disability in school life became clear. Other problems concerning parental conditions also became clear, that is, 25 parents (78.1%) had some anxiety about patient's future and only 13 parents (40.6%) told about the disease to their child. These problems should be evaluated objectively and discussed in the future.

Adolescent↗
PubMed1990

[Differentiation of infiltrates between lung cancer and noncancerous lung disease by 123I-IMP lung imaging].

Lung imaging with N-isopropyl-p-123I-iodoamphetamine (123I-IMP) was performed to estimate the pulmonary lesion imaging findings in 3 patients with bronchogenic carcinoma (2: bronchioloalveolar carcinoma and 1: adenocarcinoma) and 18 with noncancerous lung diseases (10: bacterial pneumonia, 1: viral pneumonia, 1: aspiration pneumonia, 1: radiation pneumonitis, 4: pulmonary tuberculosis and 1: obstructive pneumonitis due to an endobronchial lipoma) at 30 min and 4 hr after i.v. injection of 111 MBq of 123I-IMP. These patients all exhibited infiltrates only in the chest radiograms. Decreased uptake of 123I-IMP was observed in the cancerous infiltrating lesions in 3 patients with bronchogenic carcinoma at 30 min and 4 hr, while the uptake of 123I-IMP was normal or increased at 30 min and intense at 4 hr in all 18 noncancerous infiltrating lesions. Therefore 123I-IMP lung imaging can be used to differentiate bronchogenic carcinoma from noncancerous lung disease in patients who exhibit infiltrates only in the chest radiograms.

Adult↗
PubMed1990

Phosphoinositides metabolism in primary culture of dog thyroid cells: effects of thyrotropin and carbachol.

Thyrotropin (TSH) and carbachol stimulated in a dose-dependent manner the accumulation of 3H-glycerophosphoinositol (GPI), 3H-inositol monophosphate (IP1), 3H-inositol bisphosphate (IP2) and 3H-inositol trisphosphate (IP3) in primary cultures of dog thyroid cells prelabeled with myo-[2-3H]inositol. TSH, 250 mU/mL, stimulated 3H-IP3 level after a 10-minute incubation while 10 mU/mL TSH increased it during a 60-minute incubation. The effect of carbachol was more rapid and greater than that of TSH. Carbachol, 100 mumol/L, elevated 3H-IP3 after a 2-minute incubation and 3H-IP3 formation was increased by as little as 1 mumol/L carbachol. TSH stimulation was observed only if the cells were deprived of TSH for 5 days before being labeled with 3H-inositol. Prolongation of the labeling period or addition of TSH, (Bu)2cAMP or carbachol during the labeling increased 3H-inositol incorporation into polyphoinositides (PIPs). When the cells were labeled without any other addition, control and TSH-stimulated 3H-IP3 levels increased in parallel with 3H-PIP levels. However, TSH or carbachol-stimulated 3H-IP3 levels did not increase in proportion to 3H-PIPs level when the cells were labeled with TSH or (Bu)2cAMP. Thus, the ratio of 3H-IP3/3H-PIPs (both control and TSH or carbachol-stimulated) decreased in the cells labeled with TSH or (Bu)2cAMP, which might reflect TSH stimulation of 3H-inositol incorporation into PIPs pool(s) that do not participate in hormone-induced hydrolysis of PIPs.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed1990

Synthesis and antibacterial activity of thiazolo-, oxazolo-, and imidazolo[3,2-a][1,8]naphthyridinecarboxylic acids.

It is known that thiazolo[3,2-a][1,8]naphthyridine derivatives (3a) exhibit good antibacterial activity. Accordingly, several analogues of 3a, viz. oxazolo- and imidazolo[3,2-a][1,8]naphthyridine derivatives 3b and 3c, were synthesized and evaluated for antibacterial activity in vitro and for inhibitory activity against DNA gyrase of Escherichia coli K-12 C600. Compound 3a exhibited antibacterial activity comparable to that of ofloxacin and enoxacin against Gram-positive and Gram-negative bacteria and displayed antibacterial activity superior to that of 3b and 3c. The antibacterial activities of 3b and 3c decreased in that order. DNA gyrase inhibitory activities of 3a-c in E. coli K-12 C600 paralleled their in vitro antibacterial activity. It was found that enhancement of the DNA gyrase inhibitory activity of 3a was dependent on a certain feature of the sulfur atom of the thiazole ring.

Anti-Bacterial Agents↗
PubMed1990

Studies on topical antiinflammatory agents. V. 17-(Alkylthio)- and methoxyalkanoates of corticosteroids.

As part of our search for new topical antiinflammatory agents, a series of corticosteroid 17-(alkylthio)- and methoxyalkanoate derivatives was prepared and tested for vasoconstrictive activities. Several compounds were proved to have activity superior or comparable to that of 9 alpha-fluoro-11 beta,21-dihydroxy-16 beta-methyl-17 alpha-valeryloxy-1,4-pregnadiene-3,20-dione (betamethasone 17-valerate, BV). Among these compounds, 21-chloro-11 beta-hydroxy-17 alpha-(methylthio)acetoxy-4-pregnene-3,20-dione (5Aa) was found to have the most potent activity, being more active than BV. The structure-activity relationships of the series revealed that introduction of a (methylthio)acetate function into the 17-position as well as the 21-position of corticosteroids was effective for enhancing the topical antiinflammatory activity.

Administration, Topical↗
PubMed1990

Studies on topical antiinflammatory agents. IV. 21-(Alkylthio)acetates and (methylthio)methoxides of corticosteroids.

A series of 21-(alkylthio)acetates and 21-(methylthio)methoxides of corticosteroids were synthesized and examined for vasoconstrictive activities. The activities of seven compounds were equal to or greater than that of 9 alpha-fluoro-11 beta,21-dihydroxy-16 beta-methyl-17 alpha-valeryloxy-1,4-pregnadiene-3,20-dione (betamethasone 17-valerate, BV). Among them, betamethasone 21-(methylthio)acetate 17-propanoate (2Ca) was found to have the most potent activity, which is superior to that of BV. A structure-activity relationship study revealed that substitution of the 21-hydroxy group of corticosteroids with the (methylthio)acetate function is a useful approach for obtaining potent activity.

Administration, Topical↗