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N Monji

Publications and source records attributed to N Monji.

28 records · Page 2Linked to original sources
PubMed1980

Practical enzyme immunoassay for plasma cortisol using beta-galactosidase as enzyme label.

Enzyme immunoassay for cortisol was developed using beta-galactosidase as an enzyme label and m-maleimidobenzoyl derivatives of cortisol, i.e. cortisol-21-m-maleimidobenzoate (CT-MB) and cortisol-21-hemisuccinate conjugated with m-maleimidobenzoic acid through p-phenylenediamine linkage (CHS-MB), as the haptens coupled to sulfhydryl groups of the enzyme. This enzyme-coupling procedure was highly efficient; over 90% of the enzyme was labeled while full enzyme activity was retained. CHS-MB-beta-galactosidase conjugate showed high immunoreactivity to antibody produced against cortisol-21-hemisuccinate-bovine serum albumin but showed poor displacement with the added cortisol. CT-MB-beta-galactosidase conjugate, however, showed not only a high immunoreactivity to the antibody but also displaced well with cortisol, showing maximum sensitivity of 1 microgram/dl with a 20-microliter sample size. Modification around the linkage of cortisol derivative resulted in high sensitivity to cortisol. Cross-reactions to cortisol-21-acetate, cortisone, and corticosterone were 150%, 10%, and 7%, respectively. The accuracy, precision and correlation with RIA of this method were satisfactory for clinical application.

Galactosidases↗
PubMed1980

Phenobarbital specific antibody production: preparation of 5-phenyl-5-(4-aminobutyl) barbituric acid-bovine serum albumin conjugate.

The aminobutyl derivative of phenobarbital, 5-phenyl-5-(4-aminobutyl)barbituric acid hydrochloride, was synthesized through two synthetic pathways for the preparation of immunogen in production of phenobarbital specific antibody. The produced antiserum had high titer, specificity, affinity and sensitivity (0.5ng/ml), when examined by radioimmunoassay.

Animals↗
PubMed1979

Automated radioimmunoassay of nicotine.

We have developed an automated nonequilibrium procedure for the radioimmunoassay of nicotine. The use of a unique iodinated nicotine derivative in this procedure gave a sensitivity of 10 micrograms/l for nicotine with a between-run precision of 7.4% and within-run precision of 6.0%. Nicotine levels of 60 to 67 micrograms/ml were found in subjects 15 min after smoking one standard cigarette. The technique herein reported is a very rapid, and sensitive radioimmunoassay for nicotine and facilitates the determination of nicotine in smoking subjects during the actual process of smoking.

Adult↗
PubMed1979

Enzyme-linked immunosorbent choriomammotropin assay.

We have devloped an enzyme-linked immunosorbent assay for determining choriomammotropin (human placental lactogen) in serum. Unlabeled hormone competes with choriomammotropin-beta-galactosidase conjugate for antibody bound to polystyrene tubes. The entire assay can be performed in 2.5 h with good precision. The coefficient of variation for one sample with a mean concentration of 5.6 mg/L, assayed 10 times on the same day, was 5.7%. The coefficient of variation for nine samples (3.5 to 9.0 mg/L) assayed on five different days was 7.9%. Forty-eight clinical samples were assayed (y) and compared with results obtained by radial immunodiffusion (x). The resulting regression equation was: y = 1.05x + 0.78; r = 0.91.

Enzyme-Linked Immunosorbent Assay↗
PubMed1979

Steric hindrance enzyme immunoassay (SHEIA); a novel method in enzyme immunoassay.

We have developed a new method for separation of antibody bound and unbound enzyme conjugates. The technique as applied to the assay of choriomammotropin involves the use of beta-D-galactosylamine bound to agarose to separate the unbound choriomammotropin-beta-galactosidase conjugates for antibody bound conjugates. When beta-galactosidase was conjugated with choriomammotropin using the N-hydroxy-succinamide ester of m-maleimidobenzoic acid the affinity of the enzyme conjugate to beta-D-galactosylamine attached to agarose diminished markedly following incubation with antibody. In a typical enzyme immunoassay of choriomammotropin, 5 microliter of swelled affinity gel per tube was required to precipitate unbound enzyme following one hour gentle shaking at room temperature. Choriomammotropin antibody was used at titer of 1:1,000. The standard curve for the assay was adjusted to cover a range of 0-10 mg/l with maximum sensitivity between 1-4 mg/l.

Animals↗
PubMed1979

Plasma nicotine pharmacokinetics in dogs after intravenous administration: determination by radioimmunoassay.

Nicotine plasma levels in dogs were examined by radioimmunoassay after intravenous administration of S-nicotine at the dosage of 100 microgram/kg. After a rapid decline of nicotine level in plasma immediately following the injection, retention of the level was observed until 30 min. From that point the plasma level decreased monoexponentially. A biological half life (t 1/2, beta) of 0.61 hr we observed in dogs was similar to that in man and one half of that in rats. Total body clearance (TBC) and apparent volume of distribution (Vd, beta) in dogs were about 1/5 of that in rats. The results suggested that nicotine does not distribute in dogs as readily as in rats. Similarity in a biological half life of nicotine in dogs and humans suggested that the dog may be a better experimental model than the rate in the investigation of pharmacokinetic parameters for nicotine.

Animals↗
PubMed1976

Microbial production of amphotericin B-3H and the synthesis of its sodium desoxycholate (carboxyl-14C) complex and methyl-14C-ester.

Amphotericin B-3H with a specific radioactivity in excess of 4 muCi/mg was produced by fermentation of Streptomyces nodosus IMRU 3694 in a complex medium, using acetate-3H as a precursor. The medium employed gave a production yield of 2.5 approximately 3.5 mg/ml of amphotericin B. The most efficient incorporation of acetate-3H occurred when the precursor was added at 24 hours after inoculation. It was observed, that the amount of amphotericin A co-produced in the fermentation broth with amphotericin B was significantly reduced by the addition of ethanol to the production medium. Complete inhibition of amphotericin A production was achieved at a level of 2% ethanol in the fermentation medium without an appreciable effect on the yield of amphotericin B. Methanol, 1-propanol, 2-propanol and 1-butanol lowered the yield of both antibiotics indiscriminately. The syntheses of amphotericin B-3H-Na desoxycholate (carboxyl-14C) complex and amphotericin B-3H methyl-14C-ester are also described.

Acetates↗
PubMed1975

Studies on the absorption, distribution and excretion of radioactivity after intravenous and intraperitoneal administration of 14C-methyl ester of amphotericin B.

Distribution and balance studies with carbon-14-labeled amphotericin B methyl ester (AME) were carried out in mice. The radioactive AME was administered by either the intraperitoneal (i.p.) or intravenous (i.v.) route. In the organ distribution study, the percent radioactivity accumulating in the lung of i.v. treated mice at 1 hour after administration was about 150 times greater than that observed when the intrapertinoneal route was used. No accumulation of radioactivity with time was detected in the kidneys of either the i.v. or i.p. treated mice. After 4 days, about 51% of the total radioactivity was excreted into the urine and feces of mice after i.v. administration, but only about 15% of the total radioactivity was excreted in the case of mice receiving radioactive AME by the i.p. route. In the identification of the substances excreted in the urine, thin-layer chromatography (TLC), radioactivity, and bioautographic evidence suggest that there was no detectable de-esterification of AME to the parent compound in mice treated either intraperitoneally or intravenously with AME.

Amphotericin B↗