Biochemistry, Biophysics, and Structural Biology Commons^™

Two Classes Of Camp Analogs Which Are Selective For The Two Different Camp-Binding Sites Of Type Ii Protein Kinase Demonstrate Synergism When Added Together To Intact Adipocytes, Stephen J. Beebe, Rob Holloway, Stephen R. Rannels, Jackie D. Corbin

Bioelectrics Publications

Twenty-five cyclic nucleotide analogs were tested individually to act as lipolytic agents and to activate adipocyte protein kinase. The lipolytic potency of individual analogs correlated better with their K(a) for protein kinase and their lipophilicity rather than with either parameters alone. Some of the most potent lipolytic analogs had high I50 values for the particulate low K(m) cAMP phosphodiesterase suggesting that their effect was not due to raising endogenous cAMP levels through inhibition of phosphodiesterase. The most potent lipolytic analogs contained a thio moiety at the C-8 or C-6 position. These analogs exhibited concave upward dose-response curves. At high concentrations …

Evaluation Of Peptide Assimilation In Ehrlich Ascites Tumor Cells, John M. Castellano

Biological Sciences Theses & Dissertations

The dipeptides glycyl-L-(³H)-leucine and L-phenylalanyl-L-(³H)-leucine were synthesized in radioactive form and utilized in the analysis of peptide transport and hydrolysis by Ehrlich ascites tumor cells. The tumor cells were cultured in the abdominal cavity of CF-1 albino mice and harvested into sterile isotonic buffer for all experimental analyses.

The results of this study reveal that the tumor cells rapidly accumulate radiolabel when incubated with the above mentioned peptides, but that the peptide is most probably hydrolyzed extracellularly and free L-(³)-leucine transported. This hypothesis is based on the observations of reduction in accumulation of radiolabel …

Electron Microscopic Demonstration Of Neural Connections Using Horseradish Peroxidase: A Comparison Of The Tetramethylbenzidine Procedure With Seven Other Histochemical Methods, Keith A. Carson, M-Marsel Mesulam

Biological Sciences Faculty Publications

Eight methods for the electron microscopic demonstration of horseradish peroxidase (HRP) labeling have been compared in adjacent series of vibratome sections of mouse lumbar spinal cord. The tracer, a HRP-wheat germ agglutinin (WGA) conjugate, was injected into the gastrocnemius muscle complex. Following retrograde axonal transport to the lumbar motor neurons and transganglionic anterograde transport of the tracer to the dorsal horn, the HRP activity was demonstrated in eight series of adjacent sections of lumbar spinal cord using eight methods. These included procedures using tetramethylbenzidine (TMB), benzidine dihydrochloride (BDHC), o-tolidine, paraphenylenediamine-pyrocatechol (PPD-PC), and 4 methods using 3,3'-diaminobenzidine (DAB). All eight methods …

In Vitro Enzymatic Assay Of Rna Methylation, Pamela Jean Eubanks Gallup

Chemistry & Biochemistry Theses & Dissertations

An assay procedure for in vitro enzymatic methylation of mannnalian ribosomal RNA has been developed in this study. The assay procedure, utilized for the comparison of normal and neoplastic methylase activities (using mouse liver and Ehrlich ascites cells as sources of enzyme), is a modification of previously published methods (52,53). A 100,000 x g supernatant (SlOO) enzyme preparation was incubated with 28S-5.8S rRNA and tritium-labeled S-adenosyl-L-methionine. The RNA was extracted, applied to DEAE cellulose paper, washed, and the radioactivity counted. The neoplastic cell methylase preparation was more active in methylating both exogenous neoplastic and normal 28S-5.8S rRNA than the normal …

The Analysis Of S-Adenosylmethionine And S-Adenosylhomocysteine In Normal And Neoplastic Cells, Kathryn Elizabeth Godburn

Chemistry & Biochemistry Theses & Dissertations

Altered patterns of methylation have been shown in both ribosomal and transfer RNA isolated from cancer cells. In contrast to the elevated activity of the methyltransferases responsible for this modification, hypomethylation appears as a general characteristic. The endogenous levels of S-adenosylmethionine and S-adenosylhomocysteine are important in relationship to their role as substrate and product of the transmethylation reaction. The levels of S-adenosylmethionine and S-adenosylhomocysteine were determined using phosphocellulose cation exchange or high pressure liquid chromatography. High voltage paper electrophoresis was used in a modified procedure to directly resolve (³⁵s) labeled S-adenosylmethionine and S-adenosylhomocysteine in small quantities of cell …

Multiple Methods Of Analysis Of 2'-O-Methylation In 5.8s Rrna, Sharon H. Ryan

Chemistry & Biochemistry Theses & Dissertations

5.8S rRNA is a low molecular weight ribosomal RNA which is found hydrogen bonded to 28S rRNA in the eucaryotic cell. There are two nucleotides which have 2'-0-methylations; a guanine residue at position 77 is fully methylated and a uridine residue at position 14 which is partially methylated. This partial 2'-0-methylation of the uridine residue has been found to vary with the tissue source, with the highest level in normal tissue and the lowest level in neoplastic tissue. In order to study the significance of this site-specific methylation, a reliable and convenient method of analysis was needed.

Early studies on …

Rapid Electroosmosis Measurements, James O. Wear

Journal of the Arkansas Academy of Science

A cell has been designed and built that allows for rapid measurement of volume moved in a definite time by electroosmosis. The cell is simple to use and is not very elaborate. Using a water jacket, the cell temperature can be controlled to ± 0.1° C. Measurements are presented for acetonitrile, dimethylformamide, and nitrobenzene at 25° C for applied voltages of 25, 50, 75, and 100 volts.

The Effect Of Sodium Chloride Upon The Fission Rate Within A Single Clone Of Paramecium Caudatum And The Heritability Of That Effect., Mary C. Adolph

Electronic Theses and Dissertations

No abstract provided.