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T Kitagawa

Publications and source records attributed to T Kitagawa.

At least 649 records · Page 36Linked to original sources
PubMed1982

High dimensional structure of the antigen-binding site of anti-viomycin immunoglobulin analyzed by enzyme immunoassay.

Precise immunological recognition of anti-viomycin antiserum at detailed parts in the structure of viomycin was studied by cross reactivities of the antiserum to viomycin and its ten analogs using an enzyme immunoassay of viomycin. The antiserum clearly recognized all minor modifications in the sixteen membered ring of viomycin, indicating that the antiserum clearly recognizes the whole structure of the sixteen membered ring. Recognition of the antiserum on the beta-lysine terminus was also examined showing that the antiserum was also recognized on this part. Thus, the anti-viomycin antiserum was deduced to recognize the whole structure of viomycin, from which the deduction was made that the anti-viomycin antibodies in the antiserum must possess cavities fitting the whole structure of viomycin. The crystal dimensions of viomycin are 13 A in length, 8 A in width, and 7 A in depth. Thus, the high dimensional structure of the binding sites of the anti-viomycin antibodies was deduced to possess cavities of a similar size to that of viomycin.

Animals↗
PubMed1982

Enzyme immunoassay of blasticidin S with high sensitivity: a new and convenient method for preparation of immunogenic (hapten-protein) conjugates.

An antibody against blasticidin S (BLS), an antibiotic effective for blast disease of rice, has been produced in rabbits immunized with a blasticidin S-protein conjugate prepared by a novel and convenient procedure devised to couple BLS to bovine serum albumin (BSA) after sodium borohydride reduction of its disulfide bonds, using N-(m-maleimidobenzoyloxy)succinimide (MBS) as a cross-linker. BLS-MBS-BSA conjugate contained about 16 BLS per BSA molecule. Enzyme labeling of BLS with beta-D-galactosidase was performed by utilizing another cross-linker, N-(gamma-maleimidobutyryloxy)succinimide by means of a convenient labeling method which we introduced last year. A double antibody enzyme immunoassay of BLS which could determine as little as 100 pg per tube of BLS was developed using labeled BLS and anti-BLS antiserum. Various commonly used drugs were found to have little reactivity in this immunoassay, indicating that the anti-BLS produced is highly specific. The titer of the anti-BLS was excellent and 10,000,000-fold diluted solution could bind with the enzyme labeled BLS.

Animals↗
PubMed1982

The preparation of puromycin antibody and its use in enzyme immunoassay for the quantification using beta-D-galactosidase as a label.

An antibody specific for puromycin (PU) was prepared by immunization of rabbits with a PU conjugate of bovine serum albumin, which was newly synthesized by coupling PU to mercaptosuccinylated bovine serum albumin via a cross-linker, N-(gamma-maleimidobutyryloxy)succinimide. Enzyme labeling of PU was performed using beta-D-galactosidase [EC 3.2.1.23] via N-(m-maleimidobenzoyloxy) succinimide. An ultrasensitive and specific enzyme immunoassay for PU was developed utilizing these reagents by a double antibody technique. The standard curve of the assay was linear in the range of 2 pg to 100 pg, and the lower limit of detection was 28.2 pm (2 pg/tube); so the enzyme immunoassay was found to be approximately 326,000 times more sensitive than a microbiological assay. Further, the enzyme immunoassay is free from interference by any purine or pyrimidine analogs, or by other drugs commonly used for the inhibition of protein synthesis. Using this assay, drug levels were easily determined in rat tissue following PU administration. Since PU is extensively available as an inhibitor of protein synthesis, the enzyme immunoassay should provide useful tool for developing biochemical and toxicity studies of PU.

Animals↗
PubMed1982

Afterloading technique for interstitial irradiation of lesions in deep-seated organs.

An afterloading procedure using iridium 192 seeds was developed for the control of both localized primary lesions that are difficult to remove and superficial residual lesions that remain after the partial removal of tumors in relatively inaccessible, deep-seated organs. This technique makes possible the delivery of a minimal radiation dose to lesions in deep-seated organs. Fewer complications result, the seeds can be adjusted at appropriate intervals in proportion to the amount of radioactivity desired, and radiation exposure to personnel can be reduced. This paper describes the techniques and apparatus used to place the seeds in the tubing. Primary lesions of the urinary bladder, the prostate gland, and the esophagus, residual lesions in the brain and lung, and metastases in intrapelvic lymph nodes were treated. No technical difficulties or complications were encountered. Radiation exposures to personnel were minimized. The results indicate that the procedure has practical applications.

Brachytherapy↗
PubMed1982

Heterotopic ossification of the hip as a complication of tetanus.

Heterotopic ossification is a very rare complication of tetanus. In one case heterotopic ossification occurred around both hip joints. The values of serum creatine phosphokinase had been elevated significantly when the patient had major muscle spasms. The elevation in serum alkaline phosphatase values following that in creatine phosphokinase values persisted for about four weeks. Partial resection of the bone mass about the right hip joint resulted in a satisfactory improvement in performance of daily activities. The specimens incised at operation revealed both lamellar and woven bone surrounded by fibrous connective tissue. Very near the bone mass were severely degenerated muscle fibers. In addition, evidence suggesting metaplasia of fibroblasts to osteoblasts was seen in some areas. Clinical and laboratory data indicate trauma as a main etiologic factor of heterotopic ossification following tetanus. Heterotopic bone formation should be considered if elevation of the serum alkaline phosphatase values persists beyond the period of elevation of serum creatine phosphokinase values. Artificial ventilation may be beneficial for preventing heterotopic ossification following tetanus if it is administered before there is significant elevation of the serum creatine phosphokinase values.

Adult↗
PubMed1982

Enzyme immunoassay for the quantification of mitomycin C using beta-galactosidase as a label.

A mitomycin C (MMC) antibody was produced following immunization of rabbits with a MMC-bovine serum albumin conjugate, which was newly synthesized by coupling MMC to mercaptosuccinylated bovine serum albumin via a cross-linker, N-maleoyl aminobutyric acid. Enzyme labeling of MMC was performed using beta-D-galactosidase (EC 3.2.1.23) via m-maleoyl benzoic acid. An enzyme immunoassay for MMC was developed utilizing these reagents by a double-antibody technique. The standard curve of the assay was linear on a logit-log plot, and the lower limit of detection was 12 nM (0.2 ng/tube) so the enzyme immunoassay was found to be approximately 25 times more sensitive than a microbiological assay. Further, the enzyme immunoassay is practically free from interference by any other anticancer drugs. No significant decrease in MMC immunoreactivity was observed following 24 hr of incubation of the drug in normal human serum or urine at 37 degrees. Using this assay, serum or urine levels of MMC can be determined accurately after administration of the drug to rats at a single dose of 600 micrograms/kg. The sensitivity and specificity of the enzyme immunoassay for MMC should provide a valuable new tool for use in pharmacokinetic and toxicity studies of MMC.

Animals↗
PubMed1982

Failure of phorbol ester TPA to promote growth of in vivo-initiated rat hepatocytes transferred into a culture system.

The effect of 12-O-tetradecanoylphorbol-13-acetate (TPA), a potent promoter in epidermal carcinogenesis, on the growth of rat hepatocytes initiated in vivo and transferred into a culture system was investigated. The hepatocytes were isolated by enzymatic perfusion from the rat liver after 12 weeks of acetylaminofluorene feeding or 2--6 weeks of diethylnitrosamine treatment. TPA did not show any promotive effect in terms of the number and size of proliferative epithelial cell foci derived from initiated hepatocytes, in contrast to the remarkable effect of phenobarbital, which is a potent promoter in hepatocarcinogenesis. The results suggest the existence of organ or target cell specificity of promoters in the 2-stage concept of carcinogenesis.

Animals↗