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Full-Text Articles in Cell and Developmental Biology

Evaluation Of Peptide Assimilation In Ehrlich Ascites Tumor Cells, John M. Castellano Jan 1984

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 …


In Vitro Enzymatic Assay Of Rna Methylation, Pamela Jean Eubanks Gallup Jul 1981

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 …


Fine Structure Of The Nucleus And Cytoplasmic Feulgen-Positive Areas In The Developing Oocyte Of Argus (Persicargas) Radiatus, Bonnie J. Harding Apr 1981

Fine Structure Of The Nucleus And Cytoplasmic Feulgen-Positive Areas In The Developing Oocyte Of Argus (Persicargas) Radiatus, Bonnie J. Harding

Biological Sciences Theses & Dissertations

A transmission electron microscope analysis of the changes that occur in the nuclear chromatin and the Feulgen-positive areas of the oocyte cytoplasm as the female develops, feeds and mates is described. The description includes analysis of oocytes from three types of females: unfed, unmated; fed, unmated; and fed, mated. In all types, dense material passes through the extremely porous nuclear membrane where it accumulates in the cytoplasm.

Nuclei of previtellogenic oocytes appear the same in all females studied. Fibrillar bodies and up to four large nucleoli are seen. No typical chromatin is seen, but structures resembling nucleosomes appear throughout the …


The Effects Of 712-Dimethylbenz (A) Anthracene On Ovarian Steroidogenesis And Uterine Growth In The Mouse, Jeffrey Lynn Clark Jul 1980

The Effects Of 712-Dimethylbenz (A) Anthracene On Ovarian Steroidogenesis And Uterine Growth In The Mouse, Jeffrey Lynn Clark

Biological Sciences Theses & Dissertations

It has been previously demonstrated that 7,12-dimethylbenz(a) anthracene (DMBA) is an initiator of ovarian granulosa cell tumors. It is also known that DMBA leads to destruction of primordial oocytes, and that tumor induction may involve the interaction of pituitary gonadotropins. However, the effects of DMBA on ovarian steroidogenesis and uterine growth in relation to the tumorigenic process have not been investigated. Therefore, the present study was conducted to examine these parameters using adult C57Bl/6N mice treated in proestrus and diestrus II with 0.1 ml corn oil with or without 1.5 mg DMBA and killed 44 hours later. The uteri and …


The Analysis Of S-Adenosylmethionine And S-Adenosylhomocysteine In Normal And Neoplastic Cells, Kathryn Elizabeth Godburn Jul 1980

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 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 …


Detection Of Unique Tumor-Associated Proteins In The Urine Of Patients With Transitional Cell Carcinoma By High Resolution Two-Dimensional Polyacrylamide Gel Electrophoresis, Robert David Lehman Jul 1979

Detection Of Unique Tumor-Associated Proteins In The Urine Of Patients With Transitional Cell Carcinoma By High Resolution Two-Dimensional Polyacrylamide Gel Electrophoresis, Robert David Lehman

Biological Sciences Theses & Dissertations

A two-dimensional polyacrylamide gel electrophoretic technique was developed for the detection of unique tumor-associated proteins in urine of patients with transitional cell carcinoma (TCC) of the urinary bladder. This technique yielded high resolution of polypeptides in the urine of cancer patients. Urine was chosen as a source of tumor-associated components because the location of the tum or should release already solublized tum or substances in to the urine.

Urinary proteins were concentrated and then analyzed by the two - dimensional electrophoretic technique using isoelectric focusing in the first dimension and sodium dodecylsulfate - polyacrylamide gel electrophoresis in the second dimension. …


A Potential Macroregulatory Mechanism For Growth Regulation In Neurospora Crassa, Martha Mooney Jan 1979

A Potential Macroregulatory Mechanism For Growth Regulation In Neurospora Crassa, Martha Mooney

Biological Sciences Theses & Dissertations

Neurospora produces a phase specific, cationic mucopolysaccharide composed primarily of galactosamine (GAG-MP) which becomes part of the cell wall and is later secreted into the media. Its appearance coincides with the onset of the restricted phase of growth and causes efflux of small molecular weight metabolites when incubated with conidial cells. This activity may be a product of electrostatic interactions of the GAG-MP with the conidial plasma membrane. The activity is blocked by acetylation of the primary amines on the molecule, digestion by enzymes that hydrolyze carbohydrate linkages and the inclusion of NaCl (lM) in the GAG-MP/conidia reaction mixture. The …


Sodium Dodecyl Sulfate Polyacrylamide Gel Electrophoretic Studies Demonstrating Cytoplasmic Protein Components Unique To The Mycelial Phase And To The Yeast Phase Of Candida Albicans, Theresa Catherine Burgess Apr 1976

Sodium Dodecyl Sulfate Polyacrylamide Gel Electrophoretic Studies Demonstrating Cytoplasmic Protein Components Unique To The Mycelial Phase And To The Yeast Phase Of Candida Albicans, Theresa Catherine Burgess

Biological Sciences Theses & Dissertations

Blastospore and mycelial cytoplasmic extracts from four strains of Candida albicans, varying in virulence, were compared by sodium dodecyl sulfate (SDS) polyacrylamide disc gel electrophoresis Cytoplasmic extracts were made by disrupting the cultures in a Braun homogenizer followed by ultracentrifugation. The supernatant fractions were then resolved on polyacrylamide gels containing SDS. Each of the preparations yielded a distinct pattern. There were mycelial specific and blastospore specific protein bands. There were more components resolved from the blastospore phase cytoplasmic extracts than from the mycelial phase cytoplasmic extracts. There were bands common to both phases. These results demonstrate protein components unique …


Comparison Of Interferon Produced In Vitro By Monkey Kidney Cells Demonstrating Interference Against Polio Ii, Coxsackie A-9, Influenza A2/Hong Kong/68, And Echo-9 Viruses, Archer Duncan Farmer Jr. Jan 1974

Comparison Of Interferon Produced In Vitro By Monkey Kidney Cells Demonstrating Interference Against Polio Ii, Coxsackie A-9, Influenza A2/Hong Kong/68, And Echo-9 Viruses, Archer Duncan Farmer Jr.

Biological Sciences Theses & Dissertations

Abstract unavailable


Cytogenic Studies Of A Chesapeake Bay Population Of Molgula Manhattensis (Dekay) (Ascidiacea: Stolidobranchia), Elizabeth A. Crawford Jul 1973

Cytogenic Studies Of A Chesapeake Bay Population Of Molgula Manhattensis (Dekay) (Ascidiacea: Stolidobranchia), Elizabeth A. Crawford

Biological Sciences Theses & Dissertations

Abstract unavailable.


The Effects Of The Cyclic 3'5'-Monophosphate Of Adenosine And Its Dibutyryl Derivative On The In-Vitro Immunization Of Mouse Spleen Cell Suspensions, James A. Blanks Apr 1972

The Effects Of The Cyclic 3'5'-Monophosphate Of Adenosine And Its Dibutyryl Derivative On The In-Vitro Immunization Of Mouse Spleen Cell Suspensions, James A. Blanks

Biological Sciences Theses & Dissertations

Abstract unavailable.