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Biomedical subjects

M Mizugaki

Publications and source records attributed to M Mizugaki.

At least 109 records · Page 6Linked to original sources
PubMed1994

Monoclonal antibody-based enzyme-linked immunosorbent assay for glycyrrhizin and its aglycon, glycyrrhetic acid.

Monoclonal antibodies (MoAbs) specific for glycyrrhetic acid (GA) were prepared and characterized. Obtained MoAbs (AGA-1, AGA-3, and AGA-6) reacted with GA dose-dependently, but not with glycyrrhizin (GL), carbenoxolone, and steroids. Next, an enzyme-linked immunosorbent assay (ELISA) system using AGA-1 was established. The standard curve showed good linearity between 0.01 and 1000 ng/ml of GA, and the detection limit was 5 pg/ml. Recovery, and intra- and interassay variations of this assay system was satisfactory. GL was also measurable quantitatively after acid-hydrolysis of the samples. The developed ELISA system would be useful to determine GL and GA in biological samples or drugs as an alternative method to high performance liquid chromatography (HPLC).

Antibodies, Monoclonal↗
PubMed1993

An immunohistochemical analysis for cancer of the esophagus using monoclonal antibodies specific for modified nucleosides.

BACKGROUND: Modified nucleosides such as 1-methyl-adenosine and pseudouridine exist as minute components of transfer ribonucleic acid (tRNA) and are excreted in the urine in large amounts in the presence of malignancy. Although use of these modified nucleosides as tumor markers has long been studied and many reports have detailed their relationship with malignant tumors and the urinary excretion of various modified nucleosides, there have been no reports on modified nucleosides in esophageal carcinoma. METHODS: Monoclonal antibody patterns against 1-methyladenosine and pseudouridine were studied in esophageal carcinoma, freshly resected esophageal carcinoma tissue specimens fixed in 10% neutral formaldehyde solution, embedded in paraffin, and sectioned for immunohistochemical study. Inhibition enzyme-linked immunosorbent assay (ELISA) was used to examine urinary excretion of these modified nucleosides in patients with esophageal carcinoma. RESULTS: Although rare in normal esophageal epithelium, these modified nucleosides were strongly stained in esophageal carcinoma cells. Most carcinoma cells exhibited a cytoplasmic pattern, although some cells at the infiltrating edge displayed a nuclear pattern. These modified nucleosides were intensely imaged in 11 of 12 cultured esophageal cell lines, the exception being one line that had a much longer doubling time. Using ELISA, urinary excretion of these modified nucleosides was found to be significantly higher in patients with esophageal carcinoma than in healthy subjects; such excretion correlated with carcinoma size and stage and tended to decrease after treatment. CONCLUSIONS: These findings indicate that the modified nucleosides 1-methyladenosine and pseudouridine may be useful as tumor markers for esophageal carcinoma.

Adenosine↗
PubMed1993

[Parenteral replacement of 1-T4 in hypothyroid patients with esophageal stenosis and unconsciousness].

Hypothyroid patients are usually treated with in an oral administration of 1-T4. When oral administration is impossible because of esophageal stenosis or unconsciousness in such patients, parenteral replacement is required. We prepared a solution of 1-T4 50 micrograms/ml for intravenous administration in Tohoku University Hospital as follows: 5mg of 1-T4 (Nakarai Co.) was dissolved in 1ml of 0.1N NaOH and diluted with 0.9% NaCl and sterilized with membrane filter. Two patients with esophageal stenosis due to thyroid cancer and esophageal cancer and one in a coma due to adrenal crisis had replacement with intravenous 1-T4. Initial doses of 12.5 micrograms or 25 micrograms diluted with 100ml of 0.9% NaCl containing 1% albumin were given by drip infusion. Every week 12.5 micrograms or 25 micrograms of 1-T4 was increased. By replacement of low doses, 50 micrograms or 75 micrograms, serum T4 reached a normal level. No adverse action was observed during or after parenteral replacement. The preparation of 1-T4 was stable at least for one year and 11 months. Parenteral replacement of T4 is a useful and safe method for patients who are unable to take drugs orally.

Aged↗
PubMed1993

Immunocytochemical localization of delta 3, delta 2-enoyl-CoA isomerase and NADPH-dependent-2,4-dienoyl-CoA reductase in rat kidney.

Localization of delta 3, delta 2-enoyl-CoA isomerase (ECI) and NADPH-dependent-2,4-dienoyl-CoA reductase (DCR) in the rat kidney was investigated by immunocytochemical techniques. The kidneys were perfusion-fixed and embedded in Epon or LR White. For light microscopy, semi-thin sections of Epon-embedded materials were stained by the immunoenzyme technique after the epoxy resin was removed by treatment with sodium ethoxide. For electron microscopy, ultra-thin sections of LR White-embedded materials were stained by the protein A-gold technique. By light microscopy, the S1 segment of the proximal tubule was most heavily stained for ECI and DCR whilst S2 and S3 segments showed intermediate staining. A weak staining reaction was observed in the distal tubule and the medullary collecting tubule. In the cortical collecting tubule, heavily stained cells were present between weakly stained cells. By electron microscopy, gold particles showing the antigenic sites for ECI were confined mainly to the mitochondria, but few particles were observed in the peroxisomes. Gold labeling for DCR was localized both in the mitochondria and the peroxisomes. The labeling intensity of the peroxisomes was much higher than that of the mitochondria. The results suggest that metabolism of unsaturated fatty acids occurs mainly in the mitochondria and the peroxisomes of the proximal tubule in the kidney.

Animals↗
PubMed1993

Distribution of carbon-11 labeled methamphetamine and the effect of its chronic administration in mice.

[11C]Methamphetamine, a psychotropic agent, was synthesized by N-methylation of amphetamine with [11C]CH3 I in hopes that it could be applied in the near future to assist positron emission tomography (PET) in the imaging of its distribution in the human brain. The regional distribution of [11C]methamphetamine was investigated in the mice brain at various intervals after an intravenous (i.v.) injection. Radioactivity was higher in the hypothalamus, cortex, striatum and hippocampus. Furthermore, in chronically administered mice, the uptake of [11C]methamphetamine was higher in the striatum than those in other regions. The regional differences in the distribution of methamphetamine in the mice brain may enable the imaging of its distribution by PET using [11C]methamphetamine.

Animals↗
PubMed1993

Cytotoxic effect of hinokitiol and tropolone on the growth of mammalian cells and on blastogenesis of mouse splenic T cells.

Hinokitiol (I) and tropolone (II) showed characteristic cytotoxic effects in vitro on five kinds of human and murine cell lines and blastic lymphocytes from mouse splenocytes. The cytotoxic effect of I on the growth of murine and human tumor cell lines, including RL male-1, MH134, HL60, K562 and KATO-III was definite when examined by thymidine incorporation into DNA and its 50% inhibitory concentration (IC50) on all cells was 0.3-0.6 microgram/ml. Compound II also showed comparable cytotoxic effects on these cell lines, indicating a little lower activity when compared to I. Furthermore, I and II also completely suppressed the [3H]thymidine ([3H]TdR) incorporation of mitogen-induced blastic lymphocytes. The suppressive activity on mouse lymphocyte proliferative response to concanavaline-A was also found with both compounds at a low concentration of 0.32 microgram/ml. As compound I is known to be of fairly low toxicity (LD50: 453 + 24 mg/kg in mice), the antitumor and immuno-suppressive effect of hinokitiol (I) should be further investigated.

Animals↗
PubMed1993

[Expression of modified nucleoside, 1-methyladenosine in intraocular tumors and the retinas].

1-methyladenosine is one of the modified nucleosides, the levels of which are elevated in urine of patients with malignant tumors. We report herein immunohistological expression of 1-methyl-adenosine in tumor cells and retinas. Eight retinoblastomas, 4 malignant melanomas, two metastatic choroidal tumors, 3 retinal dysplasias, one intraocular hemorrhage and 5 normal eye retinas in human were examined. In addition, 8 experimental rabbit choroidal tumor XV2s, and 5 normal rabbit retinas were examined. 1-Methyladenosine was expressed in almost all malignant tumors and retinas with these tumors, while there was little expression in benign tumor cells, retinas with benign tumor and retinas in normal eyes. Results in rabbits were almost the same as in humans. Examination of expression of 1-methyladenosine is expected to be useful for the histological diagnosis of intraocular tumors.

Adenosine↗
PubMed1992

Alterations in biodistribution of 11C-methamphetamine (MAP), 14C-MAP, and 123I-N-isopropyl-iodoamphetamine (IMP) in MAP- and cocaine-sensitized animals.

Alterations in brain distribution of 11C-MAP, 14C-MAP, and 123I-IMP in MAP- and cocaine-sensitized animals were examined to investigate the mechanism involved in increased dopaminergic transmission and behavioral sensitization. First, a significant increase in 11C-MAP radioactivity in the striatum and hypothalamus was found in the mice pretreated with MAP for 7 days. Secondly, in MAP-sensitized rats, marked increases in 14C-MAP radioactivity were found in the striatum and limbic forebrain, respectively (370% and 650%). These findings may propose a new hypothesis that subchronic MAP administration may result in a long-term change in the presynaptic cell membrane at the nerve terminal which may in turn cause an increase in both MAP and DA uptake accompanied by an increased release of DA at the synaptic cleft.

Amphetamines↗
PubMed1992

cDNA cloning of mitochondrial delta 3, delta 2-enoyl-CoA isomerase of rat liver.

A 1.08 kbp cDNA encoding rat liver mitochondrial delta 3, delta 2-enoyl-CoA isomerase (ECI) of 298 amino acid residues (Mr 32,895) was isolated from rat liver lambda gt11, lambda gt10 cDNA libraries by the combination of an immunochemical method with a rabbit-antibody against rat liver ECI and a plaque hybridization method. The deduced amino acid sequence from the cDNA indicates that ECI is synthesized with an amino-terminal extrasequence of 35 amino acid residues and processed to the mature enzyme (Mr 29,256).

Amino Acid Sequence↗
PubMed1992

Analysis of the eicosapentaenoic acid (EPA) metabolite delta 17-6-keto-PGF1 alpha in human plasma by GC/SIM using [18O] delta 17-6-keto-PGF1 alpha.

A method of the microdetermination of delta 17-6-keto-PGF1 alpha, a hydrolyzed metabolite of PGI3, is described. An authentic delta 17-6-keto-PGF1 alpha (120 mg) was prepared from eicosapentaenoic acid (EPA) incubated with homogenate of bovine aortic intima. [18O]delta 17-6-Keto-PGF1 alpha was synthesized by repeating base-catalyzed hydrolysis of methyl ester derivatives in [18O]water, to obtain an internal standard in gas chromatography/selected ion monitoring (GC/SIM) of delta 17-6-keto-PGF1 alpha. Good linear response over the range of 10 pg-10ng was demonstrated. Chromatographic conditions using a MP-65HT column presented nearly baseline separation of delta 17-6-keto-PGF1 alpha and 6-keto-PGF1 alpha. We were able to detect delta 17-6-keto-PGF1 alpha in the range from 6 to 26 pg/ml of the human plasma. The present method can be applied to the determination of delta 17-6-keto-PGF1 alpha in the human urine and plasma.

6-Ketoprostaglandin F1 alpha↗
PubMed1992

Separation and concentration of delta 17-6-keto-PGF1 alpha using monoclonal antibody to omega 3-olefin structure of trienoic prostanoids.

A monoclonal antibody against cis-3-hexen-1-ol was prepared and used to separate and/or concentrate delta 17-6-keto-prostaglandin F1 alpha (PGF1 alpha) in the human sera. cis-3-Hexen-1-ol was conjugated with the human serum albumin (HSA) according to the N-succinimidylester method and hyperimmunized to BALB/c mouse. The monoclonal antibodies were obtained from hybridoma clones established by a fusion between SP2/0-Ag14-k13 mouse myeloma cells and splenocytes of a mouse. A monoclonal antibody, named 4G9-12B, recognized the epitope characteristic for omega 3-olefin structure. The 4G9-12B antibody became more specific for delta 17-6-keto-PGF1 alpha than 6-keto-PGF1 alpha by applying inhibition ELISA using amino-residue coating plates. Using the prepared immunoaffinity columns of this antibody, delta 17-6-keto-PGF1 alpha was clearly detected in 6 pg/ml of the human blood sera by GC/MS analysis. These results suggest that the monoclonal antibody to the partial structure of trienoic prostanoid, omega 3-olefin unit, and that its immunoaffinity columns are useful in separating and concentrating delta 17-6-keto-PGF1 alpha in the human blood or urine.

6-Ketoprostaglandin F1 alpha↗
PubMed1992

[Extra-weak chemiluminescence of drugs. XIV. Quenching effects of anthraquinones on the extra-weak chemiluminescence from lipid peroxidation in rat brain homogenates].

Quenching effects of anthraquinones on the extra-weak chemiluminescence (CL) derived from lipid peroxidation in rat brain homogenates were investigated. Such anthraquinone derivatives as emodin, rhein, and alizarin quenched the CL, while anthraquinone did not quench the CL. A linear relationship between CL-quenching activity and inhibitory rate of malondialdehyde production of various compounds was demonstrated. This technique is useful for the screening method of antioxidants.

Animals↗
PubMed1992

The influence of tetrodotoxin on the toxic effects of aconitine in vivo.

Both aconite toxins (aconitine, mesaconitine, and hypaconitine) and a pufferfish toxin (tetrodotoxin, TTX) were detected in the blood of a legal autopsy case. In order to elucidate the in vivo influence of TTX on the toxic effects of aconitine, a mixture of aconitine and TTX was administered to male ICR mice orally or intraperitoneally. The animal experiments revealed that the time of death due to aconitine was significantly delayed in proportion to the dose of TTX compared with the case for aconitine alone, and that the mortality of aconitine was lowered by TTX when the dose ratio of the two toxins was in a particular range. Accordingly, it is thought that the toxic effects of aconitine are attenuated by TTX in vivo.

Aconitine↗
PubMed1992

Diagnostic use of anti-modified nucleoside monoclonal antibody.

By use of monoclonal antibodies (MoAbs) termed APU-6 and AMA-2, we determined the usefulness of urinary modified nucleosides, pseudouridine and 1-methyladenosine, as markers for malignancy. In patients with leukemia and other forms of cancer, these nucleosides elevated significantly and reflected the disease status of patients. The immunohistochemical analysis showed that cancer cells were specifically stained with the MoAbs. Chemical identification of the cellular components reactive with the MoAbs revealed that APU-6-associated antigens were mainly rRNA and AMA-2-associated antigens were mainly tRNA. These results suggest that APU-6 and AMA-2 would be useful tools for clinical and biological studies of cancer.

Adenosine↗
PubMed1992

Selective purification of two distinct protein kinases (C-kinase and casein kinase II) from the membrane fraction of mouse brain by NED-affinity column chromatography.

By means of NED-affinity column chromatography, two distinct protein kinases have been selectively purified from the crude membrane extract of mouse brain. One (designated P-I kinase) was eluted from the column by the buffer containing 5 mM EGTA and the other (designated P-II kinase) was eluted by the buffer containing 0.6 M KCl. The activity of A-kinase was detected in the column passed through fraction. Biochemical characteristics of P-I and P-II kinases corresponded exactly to those of C-kinase and casein kinase II (CK-II), respectively. In addition, immunoprecipitate experiment using anti-CK-II antiserum against the beta-subunit of Drosophila CK-II showed that P-II kinase is identical to CK-II and the 62 kDa cellular polypeptide is associated with the kinase.

Animals↗
PubMed1991

Novel derivatization and immunoextraction to improve microanalysis of 11-dehydrothromboxane B2 in human urine.

A new, highly selective procedure for the determination of 11-dehydrothromboxane B2 (11-dehydro-TXB2) in human urine is described. Following the addition of [19,19,20,20-2H4]11-dehydro-TXB2 as an internal standard, samples were extracted with an affinity column of anti-11-dehydro-TXB2. Conversion of the immunoextracted 11-dehydro-TXB2 into its 1-methyl ester-11-n-propylamide-9,12,15-tris-dimethylisopropylsilyl ether derivative was followed by gas chromatography-selected-ion monitoring. The mass spectrum of the 11-dehydro-TXB2 derivative was dominated by the base peak ion of [M-C3H7]+ at m/z 698, which accounted for more than 10% of the total ion current. A typical result showed that the immunoaffinity purification procedures provided an extremely clean alternative to more conventional methods of chromatographic fractionation, and that interfering substances from the urine matrix were almost entirely eliminated during the microanalysis.

Antibodies, Monoclonal↗
PubMed1991

Detection of heat-stable delta 3,delta 2-enoyl-CoA isomerase in rat liver mitochondria and peroxisomes by immunochemical study using specific antibody.

The subcellular distribution of delta 3,delta 2-enoyl-CoA isomerase [EC 5.3.3.8] and the inducing effect of clofibrate, a peroxisomal proliferator, on the enzyme activity were examined in rat liver. From the results of spectrophotometric investigation of the fractions, which were prepared by sucrose discontinuous gradient centrifugation from the light mitochondrial fraction, the isomerase activity was found in the fractions enriched in mitochondria and those enriched in peroxisomes of the control and the clofibrate treated rat livers. The anti-isomerase antibody reacted with both the mitochondrial isomerase and the peroxisomal isomerase, revealing a single band with an apparent molecular weight of 30,000. However, the isomerase was induced by clofibrate administration mainly in the mitochondrial fraction. These results suggest that delta 3,delta 2-enoyl-CoA isomerase is located in the mitochondria and the peroxisomes of the normal rat liver, and that the isomerase in the mitochondria is induced by clofibrate administration.

Animals↗