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Activation In Vitro Of Transfer Rna-Guanine Ribosyltransferase By Protein Kinase C, Panayota Eriotou
Activation In Vitro Of Transfer Rna-Guanine Ribosyltransferase By Protein Kinase C, Panayota Eriotou
Chemistry & Biochemistry Theses & Dissertations
The purpose of this study was to isolate and purify the enzymes, transfer RNA-guanine ribosyltrasferase and protein kinase C, and to determine whether the phosphorylating enzyme activates the insertion enzyme in vitro. Transfer RNA-guanine ribosyltransferase lost activity within several days after isolation and total, complete reactivation was accomplished in the presence of protein kinase C. This demonstrated that ribosyltransferase's instability is related to the degree of its phosphorylation. It is proposed that modification of tRNA is controlled by protein kinase C. Deactivation of the insertion enzyme leads to hypomodified tRNA which in turn is associated with neoplasia. Potential use …
A Potentiometric Gaseous Hydrogen Sensor, Anne Guillory
A Potentiometric Gaseous Hydrogen Sensor, Anne Guillory
Chemistry & Biochemistry Theses & Dissertations
The development of a potentiometric gaseous hydrogen sensor using a 75% palladium - 25% silver alloy as a selectively hydrogen permeable electrode is described. The sensor showed some promise when used with a molten base electrolyte. Other electrolytes are investigated at ambient and higher temperatures. Various cell designs including a platinum/silver-silver chloride sensor with a gel electrolyte are discussed.
The Determination Of Clomiphene Citrate And Tamoxifen In Human Blood Plasma And Semen, Janice Irene Kiss
The Determination Of Clomiphene Citrate And Tamoxifen In Human Blood Plasma And Semen, Janice Irene Kiss
Chemistry & Biochemistry Theses & Dissertations
Triphenylethylene antiestrogen compounds are used to stimulate ovulation in anovulary women and spermatogenesis in oligozoospermatic males. Clomiphene Citrate (CC) is given therapeuticaly as a mixture of the trans (E) and cis (Z) isomers. Each of these isomers has its own characteristic agonist-antagonist profiles. Only the trans form of Tamoxifen (T) is administered therapeutically.
HPLC methodologies were developed for the determination of CC and Tin human blood and seminal plasma. The methodologies involved extraction of the triphenylethylene compounds using hexane, followed by evaporation of the hexane under N2. The residue was then taken up in a volume of HPLC …
Microwell Based Solid Phase Competitive Enzyme Immunoassay For Estradiol And Estriol, Jeng-Ting Yang
Microwell Based Solid Phase Competitive Enzyme Immunoassay For Estradiol And Estriol, Jeng-Ting Yang
Chemistry & Biochemistry Theses & Dissertations
A sensitive and simple microwell based competition enzyme immunoassay for the quantitative determination of estradiol (E2) and estriol (E3) was developed. Nicrowells coated with antibody were incubated with antigen followed by adding horseradish peroxidase (HRPO) conjugate. The assay, which can be performed within two hours at room temperature, involved simultaneous incubation of E2 - or E3-HRPO conjugate and serum sample in polystyrene microwells coated with anti- E2 or anti-E3 gamma globulin fraction.
Gamma globulin was isolated from whole anti-serum by DEAE-cellulose chromatography. A carbodiimide coupling method was utilized to prepare the …
Development Of A Solid Phase Enzyme Immunoassay For Total Serum Testosterone, Li Li
Development Of A Solid Phase Enzyme Immunoassay For Total Serum Testosterone, Li Li
Chemistry & Biochemistry Theses & Dissertations
An enzyme-labeled immunoassay of sufficient range and sensitivity was developed for serum testosterone determination. In this method, the testosterone in the serum sample and testosterone-HRPO conjugate compete with each other for the limited antibody binding sites on the anti-testosterone gamma globulin coated microwell. The assay can be performed in only 2.5 hours.
The gamma globulin fraction was isolated from the anti-testosterone whole serum by DEAE-cellulose column chromatography. Testosterone-peroxidase conjugate was prepared by a carbodiimide coupling method. The interference which arises from the binding of testosterone to steroid hormone binding protein was eliminated by the addition of 17 beta-estradiol. All assay …
Separation Of Transfer Rna Isoacceptors By Reversed Phase W-Porex C-4 High Pressure Liquid Chromatography, Christine D. Witte
Separation Of Transfer Rna Isoacceptors By Reversed Phase W-Porex C-4 High Pressure Liquid Chromatography, Christine D. Witte
Chemistry & Biochemistry Theses & Dissertations
Transfer RNA (tRNA), is a complex class of small molecules which have been proven to play a major role in protein synthesis. Transfer RNA is composed of 20 families of isoacceptors which may recognize only one particular amino acid. This family of isoacceptors may differ from each other by primary sequence or modified nucleosides. Queuine is a modified nucleoside which is found in the anticodon regions of tRNA isoacceptors for asparagine, aspartic acid, tyrosine and histidine. Queuine has gained the interest of many researchers since queuine deficient tRNA was found in many neoplastic and undifferentiated cell-lines. It is often difficult …
The Reaction Of Organoboranes With N-Chloro-N-Sodiocarbamates: A Convenient Synthesis Of N-Alkylcarbamates, Nanette M. Wachter-Jurcsak
The Reaction Of Organoboranes With N-Chloro-N-Sodiocarbamates: A Convenient Synthesis Of N-Alkylcarbamates, Nanette M. Wachter-Jurcsak
Chemistry & Biochemistry Theses & Dissertations
N-alkylcarbamic acid esters are used extensively as fungicides, herbicides and pesticides. Industrial methods of preparation employ highly toxic reagents in their synthesis. Convenient and safe alternative methods are necessary.
Organoboranes are electrophilic compounds which can be employed as a source of alkyl substituents. They have been shown to successfully transfer alkyl groups to the nitrogen of chloramines. N-Alkylation of carbamic acid esters by reacting the corresponding N-chloro-N-sodiocarbamate with a variety of trialkylboranes is described. The yields of the various N-substituted products are discussed.
Two synthetic methods were devised. Originally, an equivalent of the isolated N-chlorocarbamate salt was added to the …
A Pulse Gas Chromatographic Method For Determining The Dispersion And Surface Area Of Co Oxidation Catalysts, Susan Kay Ohorodnik
A Pulse Gas Chromatographic Method For Determining The Dispersion And Surface Area Of Co Oxidation Catalysts, Susan Kay Ohorodnik
Chemistry & Biochemistry Theses & Dissertations
Catalysts composed of platinum and/or palladium on tin(IV) oxide supports with or without silica gel have been developed for the recombination of carbon monoxide and oxygen to form carbon dioxide for use in carbon dioxide lasers. A pulse gas chromatographic method has been developed to measure the chemisorption properties of the catalysts. From the chemisorption measurements, the active surface area and dispersion of the catalysts have been determined.