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Biomedical subjects

S Tamura

Publications and source records attributed to S Tamura.

At least 541 records · Page 30Linked to original sources
PubMed1990

[Effect of danazol on bone mineral content and bone metabolism in patients with endometriosis].

Danazol, which is commonly employed in the treatment of endometriosis creates a low estrogen and high androgen condition by suppressing ovarian steroidogenesis. When a reproductive-aged woman suddenly develops low estrogen, even if it is reversible, it is possible that it can have some effect on her bone mineral content and there is the danger that this might constitute a risk factor in the development of postmenopausal bone metabolism. In 12 cases of endometriosis (average age 42.2) 400 mg/day Danazol was given for 4 months to determine if a low estrogen and high androgen condition actually continued. The effect on the bone metabolism which provides a background to metacarpal bone mineral content was also examined in comparison with before and after seven months' administration. As a result, after Danazol administration, estradiol showed a tendency to decrease and dehydroepiandrosterone showed a tendency to increase although no significant change in the estrogen and androgen level was recognized. There was also no change on the bone mineral content and there was no significant change in bone metabolism, calcitonin excepted. Therefore, from the results of calcitonin evaluation, 400mg/day Danazol administered for 4 months does not seem to be absorbed by bone and at least appears not to have any significance as a bone metabolism risk factor.

Adult↗
PubMed1990

[A case report of high plasma renin activity in chronic pulmonary disease and the effect of angiotensin-II-analogue (1-sarcosine, 8-isoleucine-angiotensin-II)].

Five patients with chronic pulmonary diseases (3 pulmonary emphysema, 1 chronic respiratory failure caused by old tuberculosis, 1 diffuse panbronchiolitis) showed a marked increase of plasma angiotensin-I and PRA level, which was accompanied by an increase of angiotensin-II level, however, whose systemic blood pressure was not elevated. The intravenous infusion of angiotensin-II-analogue (1-Sarcosine, 8-Isoleucine-Angiotensin-II) elicited an antagonistic blood pressure response resembling Bartter's syndrome.

1-Sarcosine-8-Isoleucine Angiotensin II↗
PubMed1989

[CT findings of ossification of the posterior longitudinal ligament (OPLL), with special emphasis on the relationship to clinical symptoms].

To analyze the CT findings of OPLL quantitatively, stenotic rate (thickness of OPLL/A-P diameter of the spinal canal) and occupying rate (area occupied by OPLL/area of spinal canal) were correlated with severity of the myelopathy. The cervical vertebrae were most frequently involved (88.9%). The shapes of OPPL on lateral plain radiography were various but there were slightly more continuous and mixed types than segmented or protrusion types in this series. When the occupying rate exceeded 20%, myelopathy tended to appear. And when the stenotic rate became over 30%, myelopathy tended to appear. There was statistically significant tendency that the higher the stenotic rate or patient had. Therefore we concluded the stenotic rate and occupying rate were useful indicators to evaluate the severity of OPLL.

Adult↗
PubMed1989

Increased level of apolipoprotein B mRNA in the liver of ventromedial hypothalamus lesioned obese rats.

The mRNA level of apolipoprotein B (apoB), which is a principal protein component of nascent very low density lipoprotein (VLDL), was determined in parallel with the measurement of acetyl-coenzyme A (Ac-CoA) carboxylase activity in the liver of ventromedial hypothalamus (VMH) lesioned obese rats. Eight weeks after the electrolysis of the bilateral VMH, the level of apoB mRNA in the VMH-lesioned rats was about 1.5-fold higher than that in the sham-operated rats, indicating increased apoB synthesis in the liver of the VMH-lesioned obese rats. The activity of Ac-CoA carboxylase, which is a rate-limiting enzyme for the fatty acid biosynthesis, was about 1.8-fold higher in the VMH-lesioned rats. These observations indicated that VLDL synthesis is increased in the liver of VMH-lesioned obese rats.

Actins↗
PubMed1989

Expression of rat protein phosphatase 2C (IA) in Escherichia coli.

A cDNA containing the entire coding sequence of rat type 2C (IA) protein phosphatase was expressed in Escherichia coli. An extract of bacterial cells harboring the recombinant plasmid contained a major (Mr = 41,000 - 43,000) and a minor (Mr = 30,000) protein band; both of these reacted with an anti-type 2C protein phosphatase serum. The size of the major protein band agrees well with that of the 2C phosphatase conceptualized from the cognate cDNA. A Mg2+-dependent protein phosphatase activity was detected in extracts containing the recombinant protein, but not in host cell extracts. Based on these results, it is concluded that the isolated cDNA clone encodes a functional type 2C protein phosphatase.

Animals↗
PubMed1989

[Changes in hepatic circulation after hepatic arterial embolization--an analysis of factors affecting the development of collaterals].

Forty six patients with follow up angiography after hepatic arterial embolization using gelatin sponge particles were analysed to evaluate the factors affecting development of intra- and extrahepatic collaterals. Significant correlation was demonstrated between the grade of embolization and the development of collaterals (p less than 0.001). Also there was significant correlation between development of collaterals and combined use of anticancer drugs with emboli (p less than 0.001). This suggests the possibility of endothelial damages of the arteries caused by anticancer drugs, which may enhance the permanent arterial occlusion and subsequent development of collaterals. No significant correlation was demonstrated between the numbers of embolization therapy and development of collaterals in this study.

Adult↗
PubMed1989

Pig gastric (H+ + K+)-ATPase. Lys-497 conserved in cation transporting ATPases is modified with pyridoxal 5'-phosphate.

Pig gastric (H+ + K+)-ATPase can be covalently modified with pyridoxal 5'-phosphate (PLP) (about 1 mol/mol enzyme), and this modification is not observed in the presence of ATP, suggesting that PLP binds to a specific Lys residue in the ATP binding site or the region in its vicinity (Maeda, M., Tagaya, M., and Futai, M. (1988) J. Biol. Chem. 263, 3652-3656). The peptides labeled with radioactive PLP could be released from the gastric membrane vesicles quantitatively by chymotrypsin treatment, and two peptides were purified by high performance liquid chromatographies. These peptides were not obtained from vesicles incubated with PLP in the presence of ATP. The sequences of the two peptides were NH2-Asn-Ser-Thr-Asn-Lys-Phe-COOH and NH2-Ser-Thr-Asn-Lys-Phe-COOH, exactly corresponding to residues 493-498 and 494-498, respectively, of pig gastric (H+ + K+)-ATPase sequenced recently (Maeda, M., Ishizaki, J., and Futai, M. (1988) Biochem. Biophys. Res. Commun. 157, 203-209). Lys-497 was concluded to be the binding site of PLP, as pyridoxyl-Lys was identified at the corresponding position. This Lys residue is conserved in (Na+ + K+)- and Ca2+-ATPases. The possible amino acid residues in the catalytic site of gastric (H+ + K+)-ATPase are discussed.

Adenosine Triphosphatases↗
PubMed1989

Measurement of antigen-specific mouse IgE by a fluorometric reverse (IgE-capture) ELISA.

A reverse, or IgE-capture, enzyme-linked immunosorbent assay (ELISA) for measuring ovalbumin-specific IgE antibody in the serum of immunized mice has been developed. Microplate wells were first coated with a commercial anti-mouse IgE rat monoclonal antibody, and then incubated with two-fold serial dilutions of test sera with 10% normal mouse serum as diluent for the capturing of only IgE class molecules. Biotinylated ovalbumin and then beta-D-galactosidase-conjugated streptavidin were added and, finally, 4-methylumbelliferyl-beta-D-galactoside was used as the enzyme substrate. The fluorescence intensity of the reaction product (4-methylumbelliferone) was determined on a microplate fluorescence reader. The sensitivity of this assay was equal to that of passive cutaneous anaphylaxis (PCA). In contrast to indirect ELISAs this IgE-capture assay is free from competition by non-IgE antibodies. Furthermore, it requires much less antigen than the PCA assay.

Animals↗
PubMed1989

Reflex regulation of the sphincter of Oddi by intrapancreatic ductal pressure in the Japanese monkey.

Japanese monkey has a common ampullary channel. By a continuous injection of sterile saline (1 mL/min) into the pancreatic main duct, the pancreatic main ductal pressure increased from 8.4 +/- 1.0 (mean +/- SD) to a plateau level (16-25 mmHg) in 5 Japanese monkeys. The frequency and amplitude of the slow wave in electromyography of the sphincter of Oddi (SO) were significantly decreased from 14 to 2/min and 0.06 to 0.04 mV (p less than 0.01), and the frequency of the spike component significantly decreased from 53 to 14/min (p less than 0.05). As soon as infusion of saline ceased, the electromyography recovered to the original level. The mean value of the minimum loading pressure affecting myoelectrical activities of the SO was 19.8 +/- 3.0 mmHg. When the pancreatic duct was obstructed at the head, there was no significant change in the SO myoelectrographic activities in spite of increased pancreatic ductal pressure by infusion. These findings suggest that a homeostatic mechanism of pancreatic ductal pressure exists when the activity of the SO is regulated by the distending pressure in the pancreatic ductal system. This reflex regulation seemed to be mediated by the distension of the ampullary duct itself.

Ampulla of Vater↗
PubMed1989

Protection against influenza virus infection by a two-dose regimen of nasal vaccination using vaccines combined with cholera toxin B subunit.

The effectiveness of the two-dose regimen, composed of a primary intranasal inoculation of influenza A-type virus HA vaccine together with B subunit of cholera toxin (CTB) and the subsequent intranasal inoculation of vaccine alone 4 weeks later, was examined. In mice given a relatively high dose of virus A/PR/8/34 (PR-8, H1N1) HA vaccine (1.5 micrograms) both as a primary antigen with CTB (1 microgram) and as the second antigen, the secondary responses of both antiviral IgA antibodies in nasal wash and haemagglutination-inhibiting (HI) antibody in serum were much higher than those of primary responses and persisted for greater than 12 weeks after the second inoculation. Even in mice that received reduced amounts of a primary vaccine (0.03 microgram) [prepared from virus PR-8, A/Yamagata/120/86 (H1N1) or A/Fukuoka/C29/85 (H3N2)] together with reduced amounts of CTB (0.05 microgram), the subsequent inoculation of PR-8 vaccine produced both nasal IgA and serum HI antibodies and provided complete protection against homologous A-type virus (PR-8) infection. Moreover, the combination of the reduced amounts of heterologous A-type virus vaccine (A/Yamagata or A/Fukuoka) with CTB for primary inoculation and the secondary heterologous A-type virus vaccine [A/Yamagata, A/Kumamoto/37/79 (H1N1), or A/Fukuoka] resulted in high levels of cross-reactive IgA antibodies and partial cross-protection against PR-8 infection. On the other hand, a second inoculation of B/Ibaraki/2/85 vaccine failed to produce cross-reactive antibodies and to protect against PR-8 infection.(ABSTRACT TRUNCATED AT 250 WORDS)

Administration, Intranasal↗
PubMed1989

Effectiveness of cholera toxin B subunit as an adjuvant for nasal influenza vaccination despite pre-existing immunity to CTB.

In a previous paper, it was shown that cholera toxin B subunit (CTB) augments the production of protective antibodies to influenza virus when CTB is inoculated intranasally into Balb/c mice together with influenza HA vaccine. The present study was designed to determine whether the effectiveness of CTB as a potent adjuvant for nasal vaccination could be limited by pre-existing immunity to CTB. Mice were sensitized by intranasal inoculation of either 1 or 0.05 microgram of CTB 2, 4 and/or 6 weeks before nasal vaccination. They were then vaccinated by either a single inoculation of vaccine together with 1 microgram of CTB or a two-dose regimen, composed of a primary inoculation of vaccine together with 0.05 microgram of CTB and a subsequent inoculation of vaccine alone. Levels of nasal IgA antibodies to CTB increased with the increase of the dose of CTB and the frequency of CTB-inoculation. Pre-existing immunity to CTB, however, did not significantly reduce the levels of both nasal IgA and serum haemagglutination-inhibiting (HI) antibodies to influenza virus and did not change the ability of the vaccinated mice to resist viral challenge. These results suggest that a relatively low dose of CTB could be inoculated repeatedly into animals as an adjuvant for nasal vaccination.

Adjuvants, Immunologic↗
PubMed1989

Molecular cloning of rat type 2C (IA) protein phosphatase mRNA.

A full-length cDNA encoding rat type 2C (IA) protein phosphatase was isolated from a kidney cDNA library. The cDNA was identified by screening the library with oligonucleotides based on a partial amino acid sequence determined from purified rat liver phosphatase. This clone is 2.35 kilobase pairs long and has a single extended translation reading frame that predicts a 382-amino acid protein of 42,416 daltons. The deduced amino acid sequence contains segments corresponding to three peptides from rat liver type 2C protein phosphatase and two peptides from rabbit skeletal muscle type 2C phosphatase. Rat kidney type 2C protein phosphatase is distantly related to yeast adenylate cyclase but is not related to the catalytic subunits of two other protein phosphatases (types 1 and 2A).

Adenylyl Cyclases↗
PubMed1989

Intrahepatic periportal abnormal intensity on MR images: an indication of various hepatobiliary diseases.

The frequency and degree of intrahepatic periportal abnormal intensity (PAI) on magnetic resonance images in patients with or without various hepatobiliary and pancreatic diseases were analyzed. In 63 patients without hepatobiliary disease, except for a small metastatic liver tumor or cavernous hemangioma, no definite PAI was seen. Definite PAI was seen in all patients with obstructive jaundice, cholangitis, and cholangiocellular carcinoma. It was also clearly seen in all four cases of malignant lymphadenopathy in the hepatoduodenal ligament, in one of two cases of acute hepatitis, and in four of 47 cases of liver cirrhosis. However, in patients with bile duct dilatation or with gallstone or pancreatic disease without obstructive jaundice or cholangitis, no definite PAI was seen. Histologic studies of the liver performed in 23 patients with definite PAI showed edema, ductular proliferation, dilatation of lymph vessels, and inflammatory cell infiltration in portal tracts. It is concluded that definite intrahepatic PAI is a useful sign that indicates the presence of biliary or diffuse hepatic disease.

Adult↗
PubMed1989

New projection for portography.

The right anterior caudocranial oblique (RACCO) view is proposed for improved depiction of the portal venous system. It is achieved by tilting the image intensifier 25 degrees caudal and 25 degrees-30 degrees to the right and maintaining the patient in the supine position. Transarterial portography with digital subtraction angiography was performed in the RACCO and posteroanterior (PA) views in 22 patients. Comparison of the two views revealed that the RACCO view was superior to the PA view of the left main branch in 15 patients (68%) and of the right posterior lobe branch in 19 patients (86%). The RACCO view will be useful for the evaluation of the portal system in patients with primary and secondary hepatic neoplasms in whom detailed images are important for diagnosis treatment planning.

Humans↗