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Full-Text Articles in Biochemistry

Effects Of Chemical Aneuploidogens On Taxol Purified Drosophila And Mouse Brain Microtubules Polymerization And Depolymerization In Vitro, Anil Sehgal Jul 1990

Effects Of Chemical Aneuploidogens On Taxol Purified Drosophila And Mouse Brain Microtubules Polymerization And Depolymerization In Vitro, Anil Sehgal

Biological Sciences Theses & Dissertations

The effects of aneuploidogens (aneuploidy causing agents) on taxol-purified microtubules from Drosophila and mouse brain in vitro were studied by using a spectrophotometric assay and electron microscopy. Colchicine, acetonitrile, propionitrile, acrylonitrile, dimethyl sulfoxide (DMSO), griseofulvin and cadmium chloride inhibited microtubule polymerization whereas methoxyethyl acetate (MEA) and methyl mercuric chloride (MMC) did not. All aneuploidogens tested (at 50mM) resulted in reduced rate of elongation of mouse brain microtubules. MMC, cadmium chloride and DMSO resulted in increased rates of Drosophila microtubule elongation whereas the rest of the drugs resulted in decreases. The in vitro results from Drosophila correlate well with the previously …


The Role Of The Voltage Gradient In The Agarose Gel Electrophoresis Of Dna, David Wheeler Apr 1990

The Role Of The Voltage Gradient In The Agarose Gel Electrophoresis Of Dna, David Wheeler

Theses and Dissertations in Biomedical Sciences

In Part I of this dissertation, empirical equations for predicting DNA mobility during agarose gel electrophoresis (AGE) from voltage gradient are developed from the data of McDonnel (36) for electrophoresis in a 1.6% agarose gel. These equations represented the data well for DNA between 2 and 10 kilobase pairs (KBp) in length. A computer program, called GELSIM, which incorporates these equations is described in Part II. GELSIM was designed to allow researchers to analyze electrophoresis data by predicting the effect on DNA migration of altering the voltage of electrophoresis. In this way, electrophoretic banding patterns produced using different voltages could …


Regulation Of Queuine Insertion Into Transfer Rna: Effects Of Tumor Promoters, Bonnie Jean Brooks Oct 1989

Regulation Of Queuine Insertion Into Transfer Rna: Effects Of Tumor Promoters, Bonnie Jean Brooks

Chemistry & Biochemistry Theses & Dissertations

The purpose of this study was to treat normal human fibroblasts with known tumor promoters and observe queuine modification of tRNA. The queuine insertion enzyme, tRNAguanine ribosyltransferase, was studied in vivo and in vitro. Tumor promoter-treated human fibroblast cultures exhibited variable queuine-insertion rates with a transient inhibition that correlated with variable levels of queuine modified tRNA over time in culture from passages 3 — 8. In contrast the in vitro studies showed that phorbol cetera and saccharin actually increased insertion with strong evidence indicating phosphorylation as a positive modulating force of the enzyme activity. It is proposed that chronic stimulation …


Microwell Based Competitive Enzyme Immunoassay For Quantifying Serum Triiodothyronine And Thyroxine Levels, Yiwen Yang Jul 1989

Microwell Based Competitive Enzyme Immunoassay For Quantifying Serum Triiodothyronine And Thyroxine Levels, Yiwen Yang

Chemistry & Biochemistry Theses & Dissertations

A microwell based competitive enzyme immunoassay for determination of total thyroxine and triiodothyronine in human serum was developed with use of horseradish peroxidase conjugate. The assay, which can be performed in only 1.5 hours at room temperature, involves simultaneous incubation of T3- or T4- HRPO conjugate and serum sample in anti-T3 or anti-T4 gamma globulin fraction coated polystyrene microwells.

Isolation of anti-T3 and anti-T4 gamma globulin fractions were accomplished from whole antiserum by using DEAE-cellulose chromatograph. A carbodiimide coupling method was described to prepare the T4- and T3-HRPO …


Hypoxanthine-Induced Differentiation Of Cultured Human Leukemia Cells, Gayle Jennette Singleton Apr 1989

Hypoxanthine-Induced Differentiation Of Cultured Human Leukemia Cells, Gayle Jennette Singleton

Chemistry & Biochemistry Theses & Dissertations

Human cultured leukemia cells appear to have a decreased amount of inosine in their tRNA. When cells with inosine deficient tRNA are placed in a hypoxanthine fortified media, they incorporate hypoxanthine into their tRNA by the action of the enzyme tRNA-hypoxanthine ribosyl transferase. This generates the nucleoside inosine in the tRNA. The cultured human leukemia cell lines, CCRF-CEM, HL-60, and HGPRT(-) HL- 60, incorporate hypoxanthine into their tRNA, as determined by tRNA isolation, hydrolysis, and HPLC analysis. Hypoxanthine treatment dramatically inhibited cell growth in conjunction with partial induction of differentiation in the CCRF-CEM, HL-60, and HGPRT ( - ) HL-60 …


A Method For The Large Scale Purification Of Hcg (Human Chorionic Gonadotropin) From The Urine Of Pregnant Women, Chun-Shyan Kuo Oct 1988

A Method For The Large Scale Purification Of Hcg (Human Chorionic Gonadotropin) From The Urine Of Pregnant Women, Chun-Shyan Kuo

Chemistry & Biochemistry Theses & Dissertations

A large scale preparation of human chorionic gonadotropin (HCG) from the urine of pregnant women was accomplished by using kaolin adsorption, NH4OH extraction and DEAE-cellulose ion exchange. A recovery about 81% of HCG and a specific activity in the 2,000-3,000 IU/mg range was achieved using this purification method.

Two HCG activity fractions, HCG I & HCG II, were isolated from DEAE-cellulose chromatography by a stepwise sodium chloride gradient elution. HCG I was eluted at 0.01-0.02 M NaCl while HCG II was eluted at 0.12-0.02 M NaCl.

The differences between HCG I and HCG II have been studied. The …


Molecular Study Of The B19 (Human) Pathogenic Parvovirus, Jamshed Ayub Jul 1988

Molecular Study Of The B19 (Human) Pathogenic Parvovirus, Jamshed Ayub

Theses and Dissertations in Biomedical Sciences

The B19 (human) parvovirus is a small single stranded DNA virus of 5.4 kilobases. B19 is specific for erythroid progenitor cells and has been propagated in vitro only with human erythroid bone marrow. Replication of viral DNA and the viral protein products of B19 appear similar to those of other animal parvoviruses. However, B19 differs from other parvoviruses in some important aspects, which include the initiation of all transcripts at a strong left side promoter (p6) and the absence of a functional internal promoter. B19 has an unusual transcription map which is described in this study.

The transcription map of …


Modulation Of Queuine Uptake In Cultured Human Fibroblasts By Phorbol Esters And Interferons, Debra L. Crane Jul 1988

Modulation Of Queuine Uptake In Cultured Human Fibroblasts By Phorbol Esters And Interferons, Debra L. Crane

Chemistry & Biochemistry Theses & Dissertations

Queuosine, a nucleoside found exclusively in the first position of the anticodon of transfer RNA (tRNA), is generated post-transcriptionally in an exchange of guanine for queuine by the modifying enzyme tRNA-guanine ribosyltransferase. Phorbol ester tumor promoters were shown to induce queuine hypomodified tRNA, and that phorbol ester action was due, in part, to inhibition of queuine transport across the cell membrane. An unidentified protein designated conditioned medium factor (CMF) that potentiated a phorbol-induced inhibition of queuine uptake was also documented. We suggest here that phorbol ester-induced inhibition of queuine uptake is not a significant factor in inducing queuine-deficient tRNA although …


Comparison Of Surface Polysaccharides Of R. Leguminosarum Anu57 (Exo-1), R. Leg. Anu57(Pbr1an) (Nod+, Nif-), And R. Leg. Anu57(Pjb5j1) (Nod+, Nif-), Frank G. Hustmyer Jan 1984

Comparison Of Surface Polysaccharides Of R. Leguminosarum Anu57 (Exo-1), R. Leg. Anu57(Pbr1an) (Nod+, Nif-), And R. Leg. Anu57(Pjb5j1) (Nod+, Nif-), Frank G. Hustmyer

Masters Theses

Extracellular polysaccharides (EPS) and lipopolysaccharides (LPS) are suspected to be involved in the legume/Rhizobium symbiotic process. Polysaccharide compositions from the EPS, LPS, capsular polysaccharide (CPS), and small polysaccharide (SmPS) were compared between Rhizobium leguminosarum ANU57 (parent, Exo-1) and two mutants R. leg. ANU57(pBR1AN) (nod+, nif-) and R. leg. ANU57(pJB5J1) (nod+, nif-) both containing a Sym (symbiotic) plasmid insertion. R. leg. ANU57(pBR1AN) and R. leg. ANU57(pJB5J1) are nod+ on clover and peas, respectively. The nod+ mutants produce larger amounts of EPS and decreased amounts of LPS compared to …


Determination Of Erythrocyte Zinc Concentrations Using Zeeman Effect Atomic Absorption Spectroscopy, Tanya Maranda Lewis Jul 1983

Determination Of Erythrocyte Zinc Concentrations Using Zeeman Effect Atomic Absorption Spectroscopy, Tanya Maranda Lewis

Chemistry & Biochemistry Theses & Dissertations

The purpose of this research project was to develop assay procedures for determination of zinc in erythrocytes. Three methodologies were developed. The methods were evaluated on the basis of within-run and between-run precision. The most reproducible method, the 213.856 nm flame methodology, was used to determine red blood cell zinc concentrations in more than 200 samples obtained from the Neonatal Intensive care Unit at the Children's Hospital of the King's Daughters.

This study demonstrated that erythrocyte zinc levels in premature infants were similar to those of healthy adults. A linear relation between plasma and red blood cell zinc concentrations was …


Isomers Of 5.8s Ribosomal Rna, David Smith Jul 1982

Isomers Of 5.8s Ribosomal Rna, David Smith

Chemistry & Biochemistry Theses & Dissertations

When whole cell RNA was separated by high resolution PAG (i.e., polyacrylamide gel) electrophoresis, 5.8S rRNA migrated as three higher mobility intense bands, and three faint bands of lower mobility. The three intense bands represent conformational isomers which migrated as a single band under denaturing conditions on PAG. The three faint bands represent conformational isomers of a minor form of 5.8S rRNA which is elongated at the 5' terminus of the molecule. This minor form migrates as a single band of lower mobility than the major form when electrophoresed on a denaturing PAG. The minor form was determined to have …


Functions Of Deadenylation Factors In Mrna Decay And Mrna Processing Body Formation, Dinghai Zheng Sep 1980

Functions Of Deadenylation Factors In Mrna Decay And Mrna Processing Body Formation, Dinghai Zheng

Dissertations & Theses (Open Access)

Most newly synthesized messenger RNAs possess a 5’ cap and a 3’ poly(A) tail. The process of poly(A) tail shortening, also termed deadenylation, is important for post-transcriptional gene regulation, because deadenylation not only leads to mRNA translational inhibition but also is the first step of major mRNA degradation. Translationally inhibited mRNAs can be stored and/or degraded in dynamic cytoplasmic foci termed mRNA processing bodies, or P bodies, which are conserved in eukaryotes.

To shed new light on the mechanisms of P body formation and P body functions, I focused on the link between deadenylation factors and P bodies. I found …


High Resolution Two-Dimensional Electrophoretic Study Of Human Seminal Plasma Proteins, Edward E. Gaunt Jul 1980

High Resolution Two-Dimensional Electrophoretic Study Of Human Seminal Plasma Proteins, Edward E. Gaunt

Chemistry & Biochemistry Theses & Dissertations

A comprehensive biochemical screening procedure for the evaluation of seminal plasma constituents is needed which, when used in conjunction with semen analysis, can provide the physician with both qualitative and quantitative information regarding the fertility status of an individual.

High resolution two-dimensional electrophoresis is a technique whereby proteins in a complex mixture such as a biological fluid are separated in one dimension by molecular charge and in the second dimension by molecular mass. It has been the purpose of this investigation to adapt and evaluate this technique for the analysis of human seminal plasma.

Our efforts have shown that this …


The Association Of 5.8 S With 28s Ribosomal Rna, Nandita Banerjee Jan 1980

The Association Of 5.8 S With 28s Ribosomal Rna, Nandita Banerjee

Chemistry & Biochemistry Theses & Dissertations

5.8S rRNA is a low molecular weight ribosomal RNA which is noncovalently bonded to the larger ribosomal subunit 28S rRNA; through its 3' end and through its 5' end. This interaction is an integral part of the ribosome, and plays an important role in the ribosome structure and function.

There is a high degree of homology between the 5.8S rRNA primary structures of rat, turtle and chicken. The base sequence of rat 5.8S rRNA differs only in one position from that of turtle and in three positions fr.om that of cl1.icken. Tl1ere is a single purine substitution at the 5' …


Multiple Methods Of Analysis Of 2'-O-Methylation In 5.8s Rrna, Sharon H. Ryan Jan 1980

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 …