Life Sciences Commons^™

Selenium-Induced Enhancement Of Hematoporphyrin Derivative Phototoxicity In Murine Bladder Tumor Cells, Jeffrey M. Tosk

Loma Linda University Electronic Theses, Dissertations & Projects

The phototoxicity of hematoporphyrin derivative (Hpd) to murine bladder tumor (MBT-2) cells was studied in vitro. It was observed that selenium in the form of sodium selenite enhanced Hpd-sensitized photodamage in MBT-2 cells under conditions where the selenite alone was non-toxic. Sodium selenite was found to enhance the fluorescence emission of Hpd and augment the Hpd-sensitized photooxidation of tryptophan. The data indicate that sodium selenite is able to disaggregate Hpd, thereby enhancing Hpd-sensitized phototoxicity.

The Effect Of Dietary Fat Level On Tumor Development And Immunity In Balb/C Mice Fed Casein Of Wheat Gluten As Protein And Challenged With Herpes Type 2-Transformed Cells, Helen Drakou

Loma Linda University Electronic Theses, Dissertations & Projects

A high percentage of fat in the diet has been implicated through epidemiological studies in several human cancers. Studies in experimental animals have produced evidence that increasing the fat in the diet decreases the animal’s ability to restrict tumor development and growth. In previous work done in this laboratory with BALB/c mice injected with herpes simplex Type 2-transformed mouse cells (H238), the effects of a diet which greatly enhanced tumor growth was compared with one which restricted tumor growth. The latter, a low (5%) fat, low protein diet, in which the protein was casein, was also found to produce a …

The Expression Of Dna Restriction-Modification Genes Of Escherichia Coli K12, Ainu Prakash

Loma Linda University Electronic Theses, Dissertations & Projects

To facilitate the study of the expression of hsd genes in Escherichia coli K, hsdK::MudX (amp crop lac) operon fusion mutants have successfully been constructed and characterized for the first time. The results indicate that Promoters 1 and 2 for hsdK genes appear to be relatively weak, as reflected by about 50 units of beta-gal activity. Both promoters were active in all the conditions tested except during Beta-gal activity was higher in aerobic than in anaerobic growth; at 30°C and 37°C than at 42°C; and in L-broth early log phase of the culture. than in minimal media. Potential future uses …

Sprague-Dawley Rats Fed Milk Or Beef Protein : Differences In Response To 1,2-Dimethylhydrazine Carcinogenesis, Stanley W. L. Ng

Loma Linda University Electronic Theses, Dissertations & Projects

Colon cancer is responsible for a high percentage of cancer deaths in developing countries, and there is convincing epidemiological evidence that meat protein and fat in the diet increase the incidence of this form of cancer. An animal tumor model which has been used by many investigators interested in colon cancer is the 1,2-dimethylhydrazine (DMH)-rat or DMH-mouse tumor model. In previous work done in this laboratory the DMH-BALB/c mouse tumor model was used to compare the production of colon tumors in mice fed a diet using non-fat powdered milk as a source of protein with those in mice fed beef …

The Effects Of Certain Oral Bacteria On The In Vitro Growth Of Bacteroides Gingivalis, Steven G. Morrow

Loma Linda University Electronic Theses, Dissertations & Projects

The effect of nine gram positive and grain negative cocci and bacilli, which are indigenous to the oral cavity, on the in vitro growth of Bacteroides gingivalis was examined in this study. A pure culture of B. gingivalis is was obtained from the American Type Culture Collection. The nine oral test organisms were Streptococcus mitis, Streptococcus mutans, Streptococcus faecalis, Staphylococcus epidermidis, Staphylococcus aureus, Corynebacteriurn hofmanii, Lactobacillus acidophilus, Branhamella catarrhalis, and Escherichia coli. The effect on the growth of B. gingivalis of the nine test organisms was evaluated on a solid medium by use of …

Augmentation Of Natural Killer Cell Activity By Corynebacterium Parvum: Involvement Of Lipoxygenase Pathway, Gregory D. Kuo

Loma Linda University Electronic Theses, Dissertations & Projects

The ⁵¹Chromium release assay was used to measure natural killer (NK) cell activity associated with Corynebacterium parvum (CP) injection against YAC-1 and MBT-2 targets. The peritoneal exudate cells from intraperitoneal treatment of CP at different dosages consistently gave higher cytotoxicity than their respective spleen cell fractions. In contrast, CP given intravenously showed the reversed effect. Our results demonstrate that the route of administration and dosage of CP are two crucial variables for determining the effectiveness of this immunostimulant. In vitro manipulations of nordihydroguaiaretic acid, indomethacin, and prostaglandin E2 on CP-stimulated NK cells suggest that the lipoxygenase pathway is involved …

Restriction Analysis Of Bacteriophage, Ali Reza Mostaghimi

Loma Linda University Electronic Theses, Dissertations & Projects

A restriction map of DNA from bacteriophage P3-C₁ for the endonucleases BamH I, Bgl II, EcoR I, Hind III, Sac I and Sca I is described in this study. The phage DNA was determined to be a linear double stranded molecule with a unit genomic length of 31 kb. After electrophoresis in 0.5% agarose gels, the undigested DNA appeared as three molecules of 31, 62 and 93 kb in length. The Hind III digestion pattern of the individual 31 kb molecule was identical to the 62 kb and 93 kb Hind III pattern. With all enzymes except Hind III, …

Purification Of Anthrax Toxin Protective Antigen Component And Characterization Of Its Binding Interaction With Bovine Kidney Cells, Daniel Dalton Martin

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Protective antigen component of B. anthracis toxin was produced and purified to the >99% level. Toxin was purified from culture supernatant utilizing concentration and liquid chromatography techniques. Purity was determined by sodium dodecyl sulfate-polyacrylamide gel electrophoresis.

The purified protective antigen retained biological and antigenic activity as evidenced respectively by lethality in Fischer 344 rats when injected in combination with lethal factor, and by positive results on the Ouchterlony double diffussion assay.

Radioiodinated protective antigen was used both in the in vivo and the in vitro experiments.

In vivo distribution of labelled protective antigen was determined in Fischer 344 rats. Assay …

Characterization Of A Staphylococcal Trimethoprim Resistance Gene, Jerald Preston Coughter

Theses and Dissertations

Trimethoprim resistance(Tp r) is encoded by conjugative plasmids in clinically significant staphylococcal isolates. Two genetically and physically similar plasmids from S. aureus, pG01 and pGOS, have Tp r genes that map in different locations on these plasmids. In order to study the relatedness of the Tp r genes and their products to other known Tp r genes, a 1.2 kb fragment of pG01 and a 4.2 kb fragment of pGOS were cloned in E. coli and used as probes for in situ filter hybridization experiments.

A 500 base pair subclone of the original 1.2 kb fragment containing only the staphylococcal …

The Effect Of A Bacteriophage On The Competition Of Rhizobium Japonicum Strains For Nodulation Of Glycine Max (L.) Merr, Lori Kelley

Masters Theses

The symbiotic relationship between Rhizobium japonicum (Kir.) Buch. and Glycine max (L.) Merr. was the concern of this thesis. This relationship occurs naturally in soybean fields. In the field there are many different strains of Rhizobium. Some of these strains fix atmospheric nitrogen more efficiently than others resulting in a higher crop yield. The problem is the more efficient nitrogen fixers are out-competed by less efficient nitrogen fixers. In order to solve this problem the more competitive strains have to be controlled. There are two main ways to do this. One is to increase the number of the desired …

Analysis Of The Charleston, Illinois Water Supply For The Presence Of Organic Mutagens Utilizing The Ames Salmonella/Microsome Assay, Steven Lee Washburn

Masters Theses

Water samples from the Charleston, Illinois water supply and selected agricultural run-off areas were tested for the presence of organic mutagenic chemicals. The Ames Salmonella/microsome mutagenicity assay utilizing strains TA98 and TA100 was used to analyze concentrated water samples. A special set of samples was exposed to the S9 activation system coupled with the TA98 strain to simulate the mammalian metabolic system.

No mutagens were detected in any of the samples tested. Several positive and negative control systems were included in the testing system. Negative control systems were used to determine the average spontaneous reversion rates for each strain for …

Degradation Of Human Anaphylatoxin C3a By Rat Peritoneal Mast Cells: A Role For The Secretory Granule Enzyme Chymase And Heparin Proteoglycan, James Edmund Gervasoni Jr

Theses and Dissertations

Purified human C3a was iodinated (¹²⁵I-C3a) and used to study the interaction of labeled peptide with rat peritoneal mast cells (RMC). Cellular binding of ¹²⁵I-C3a occurred within 30 sec, followed by a rapid dissociation from the cell. Both the binding of ¹²⁵I-C3a and the rate of dissociation from the cell were temperature dependent. At 0°C, the binding of ¹²⁵I-C3a was increased and the rate of dissociation reduced, as compared to 37°C. Once ¹²⁵I-C3a was exposed to RMC, it lost the ability to rebind to a second batch of RMC. Analysis of the supernatants by …

Restriction Mapping And Expression Of Recombinant Plasmids Containing The Arsenic Resistance Genes Of The Plasmid R45, Terry M. Coons

Dissertations and Theses

The trivalent (arsenite) and pentavalent (arsenate) forms of arsenic are introduced into the environment through the use of arsenic in herbicides, pesticides, fertilizers, and the smelting of arsenic-bearing ores. Bacteria resistant to arsenic are readily isolated from surface waters, sewage, and clinical infections. Although some bacterial resistance is provided by inducible phosphate transport systems that discriminate against arsenate, marked resistance is carried on bacterial plasmids.

A 6.9 kilobase fragment previously derived from one such plasmid, R45, and containing the genes for inducible resistance to arsenite and arsenate was ligated into the cloning vectors puce and pUC9 in opposite orientations and …