The fixation of /sup 14/CO/sub 2/ may be required at some future time because of the significant fractional contribution of /sup 14/C, via the ingestion pathway, to the total population dose from the nuclear fuel cycle, even though the actual quantity of this dose is very small when compared to natural background. The work described here was done in support of fuel reprocessing development of both graphite fuel (HTGRs) and metal-clad fuel (LWRs and LMFBRs), and was directed to the control of /sup 14/CO/sub 2/ released during reprocessing operations. However, portions of this work are also applicable to the control of /sup 14/CO/sub 2/ released during reactor operation. The work described falls in three major areas: (1) the application of liquid-slurry fixation with Ca(OH)/sub 2/, which converts the CO/sub 2/ to CaCO/sub 3/, carried out after treatment of the CO/sub 2/-containing stream to remove other gaseous radioactive components, mainly /sup 85/Kr. This approach is primarily for application to HTGR fuel reprocessing; (2) the above process for CO/sub 2/ fixation, but used ahead of krypton removal, and followed by a molecular sieve process to take out the /sup 85/Kr. This approach was developed for use with HTGR reprocessing, but certain aspects also have application to metal-clad fuel reprocessing and to reactor operation; (3) the use of solid Ba(OH)/sub 2/ hydrate, reacting directly with the gaseous phase. This process is generally applicable to both reprocessing and reactor operation.

A cell extract from Trichosporon cutaneum containing catechol 1,2-oxygenase catalyzes the oxidation of catechol to cis,cis-muconic acid. The absorbance of the cis,cis-muconic acid at 260 nm can be correlated with the initial catechol concentration in the range 5 × 10−6 M to 5 × 10−5 M in aqueous solutions. This enzymatic assay has been applied to the determination of catechol in aqueous samples derived from coal processing.

Antisera against human placental proteins were developed in goats and rabbits, using immunoadjuvants and a prolonged injection schedule. The antisera were absorbed with normal serum proteins and then tested in immunodiffusion against normal and pregnancy sera. Two bands of precipitation due to pregnancy antigens were observed in pregnancy sera as early as 18 days after conception. Detection of these antigens has possibilities for application as an early pregnancy test.

Summary This paper discusses theoretical considerations leading to recognition of the importance of the isolation and characterization of human tumor-associated antigens (especially autoantigens) as central problems in cancer research and presents a report on progress made in attempts to develop the concepts and methods required to solve these problems. Aside from tumor and tissue extracts, five main sources of tumor antigens are considered: the isolated tumor cell membrane, the medium in which tumor cells have grown, serum from tumor patients, the human kidney (from which antigen-antibody complexes may be eluted), and urine from tumor patients. Methods of recovering and concentrating both particulate and soluble fractions are discussed. For separation of soluble materials, the development is charted of automated immunospecific methods, based on cycling immunoabsorption of antigens or antibodies on columns of immobilized antigens or antibodies or “sandwich” columns, and examples are given of separations achieved. The preparation and rationale of use of cascade systems for removing normal substances in the search for abnormal ones are discussed, and the scope of the methods is indicated. Emphasis is placed on the “amplification” inherent in the method arising from repetitive operation and from the biological amplification of the immune response in giving in a systematic manner large quantities of antigens and antibodies for use and study.

The specificity of antibodies was employed in the identification of bands separated by acrylamide gel electrophoresis by subtracting the band prior to the electrophoretic separation. This immunosubtraction was accomplished without sacrificing any of the high resolution obtained on gradient polyacrylamide gels. Using purified antibody (IgG) isolated by chromatography, the subtraction was performed in several ways. The utility of this technique was demonstrated on samples of human serum using antibodies against human transferrin, albumin, α2-macroglobulin, and whole human serum. Specific animal proteins added to the human serum samples were not subtracted.

Publisher Summary This chapter describes a useful procedure for the purification of several tRNA's from calf liver. A combination of chromatographic methods, BD-cellulose, reversed-phase, and DEAE-Sephadex, is employed to achieve the purification. Rat liver serine tRNA, purified by partition chromatography, is the only mammalian tRNA that has been sequenced. The procedure described in this chapter was developed so that a number of mammalian tRNA's could be purified in adequate quantities to permit determination of the nucleotide sequence, use as substrate for modifying enzymes, and identification of enzymatic recognition sites. Double-label experiments to identify which isoaccepting species of a tRNA has been isolated are performed on each tRNA product using RPC-5 minicolumns. The final purity of each tRNA product is defined as the respective amino acid acceptance per 3'-terminal adenosine nucleoside.

Five tRNAs (aspartic acid-2, leucine-1, lysine-2, phenylalanine, and serine-3) were isolated from crude calf liver tRNA by chromatographic procedures involving benzoylated DEAE-cellulose, reversed-phase chromatography, and DEAE-Sephadex A-50. Calculated activities (amino acid acceptance per 3′-terminal adenosine) were from 87 to 102 %. Crude calf liver tRNA contains much smaller quantities of RNA contaminants than crude tRNA from the mature beeves. The procedures for the preparation of the crude tRNA and chromatographic steps for isolation of these five tRNAs are amenable to scale-up for the preparation of larger samples.

The five chromatographically resolvable leucine tRNA's of Escherichia coli were purified by aminoacylation, chemical derivatization, benzoylated DEAE-cellulose (BD-cellulose) chromatography, basic hydrolysis, reversed-phase chromatography, and DEAE-Sephadex chromatography. The leucine tRNA-1, -3, -4, and -5 were estimated to be 80–100 % pure. The leucine tRNA-2, present in only minor amounts, was less pure. In ribosome binding experiments, leucine tRNA-1 and -2 recognized the codon CUG and leucine tRNA-5 recognized UUG. The leucine tRNA-3 and -4 did not recognize any of the known leucine codons. The method is amenable to scaleup and could be used to prepare large quantities of purified leucine tRNA's. The four arginine tRNA's from E. coli were also recovered by this method but they were less pure, possibly due to chemical damage in the derivatization step.