Organisms Commons^™

Effect Of Short Exposure Of Naoci/Edta On E. Faecalis In Extracted Human Teeth, Rylan N. Gustafson

Loma Linda University Electronic Theses, Dissertations & Projects

The purpose of this project was to study the antibacterial effect of the short exposure of 5.25% NaOCl and 17% EDTA on eight strains of Enterococcus faecalis in extracted human teeth. The crowns of 240 single rooted teeth were removed and the canals were instrumented to ISO 0.36. The canals were irrigated with 5.25% NaOCl and 17% EDTA, autoclaved and separated into eight groups of 30 teeth consisting of 20 experimental teeth, 5 positive and 5 negative controls. Each group was inoculated with one of eight different strains of E. faecalis in BHl broth and incubated for four weeks. The …

Detection Of Bacteria To Dental Tissue By Low-Light Imaging, G-Hong Robert Hsu

Loma Linda University Electronic Theses, Dissertations & Projects

Bacteria have been shown to play an important role in the development of pulp and periradicular disease. The source of the infective bacteria is most often the oral cavity. Previous studies have detected bacteria in teeth that are structurally intact that seemingly have no communication intraorally. Anachoresis has been proposed as a mechanism for localizing circulating bacteria to such teeth. In several previous bacteriologic anachoresis studies, bacteria have been found to localize in inflamed dental tissues. The criticism most commonly associated with these investigations has been the potential contribution of contaminant bacteria resulting in false positive findings.

Low-light image analysis …

Cellular Responses In Escherichia Coli To Lethal And Sublethal Doses Of Ozone, Indira Ruth Komanapalli

Loma Linda University Electronic Theses, Dissertations & Projects

Ozone is a major component of photochemical smog. High levels of this pollutant, sufficient to affect human health are found in many urban areas worldwide. Though limited studies in humans are supported by extensive findings from animal experiments, a difficulty in interpreting the results of these experiments has lead to an ambiguity on the biochemical mechanism of ozone toxicity. To elucidate the mechanism by which ozone causes cell damage and eventual cell death we conducted a comprehensive study using Escherichia coli K-12 as a model.

Studies on the comparative inactivation of bacteriophage lambda (λ), Escherichia coli, and Candida albicans …

Concentration Of Leukotrienes B4 And C4 In Human Periradicular Lesions, Elisabetta Cotti

Loma Linda University Electronic Theses, Dissertations & Projects

The 5-lipoxygenase metabolites of arachidonic acid such as leukotrienes (LT) B₄ and C₄, are potent mediators of inflammation. The purpose of this investigation was to determine the concentrations of LTB₄ and LTC₄ in human periradicular lesions. Specimens from asymptomatic and symptomatic patients were obtained and immediately frozen in liquid nitrogen. Periradicular tissues from unerupted third molars as well as chronically inflamed gingival tissues were also obtained, frozen and were used as negative and positive controls respectively. The concentrations of LTB₄ and LTC₄ were determined by the reverse phase high pressure liquid chromatography. Representative …

Determination Of Antibody Levels In Periapical Lesions Against Sixteen Oral Microorganisms By The Elisa Technique, Sammee Lee Jones

Loma Linda University Electronic Theses, Dissertations & Projects

The root canal system, which includes the periapical region of the tooth, may become infected by several types of microorganisms which are normally associated with these tissues. A bacteria-specific antibody response may occur at the local level, where various classes of immunoglobulins have been found and reported in the literature. The purpose of this study was to quantitatively measure locally produced immunoglobulin' levels in periapical lesion abscess materials and to determine the specific reactivity of these antibodies to several microorganisms which are normal flora, as well as being previously associated with the development and pathogenesis of endodontic infections. Periapical lesions …

Immunologic Mechanisms Involved With Human Endodontic Lesions, Sunita V. Prabhu

Loma Linda University Electronic Theses, Dissertations & Projects

Endodontic or root canal infection results in immunologic changes in periapical region, which causes the destruction of pulpal and periapical tissue. No definitive study has identified a specific organism or a group of organisms as a etiological agents. Past studies have indicated that immunoglobulin E play a significant role in the pathogenesis of periapical lesions. The presence of this factor suggests that some of the endodontic flare-ups may be IgE-mediated hypersensitivity reactions. Antibody levels of IgA have been quantitatively measured by ELISA and IgE by modified RAST assay, against eleven oral bacteria which are routinely isolated from such lesions. The …

The Determination Of Antibody Levels In Endodontic Patients Against Eleven Microorganisms Using Ifa And Elisa Techniques, William C. Payne

Loma Linda University Electronic Theses, Dissertations & Projects

Endodontic (root canal) infections are generally considered to be caused by the invasion of microorganisms which destroy pulp tissue and extend to the periapical region. No definitive study has identified a specific bacterium or group of bacteria as etiological agents. We quantitively measured antibodies present in the serum of 30 normal individuals and patients with either chronic (n = 30) or acute (n = 30) periapical lesions with the indirect fluorescent antibody (IFA) and enzyme-linked immunosorbent assay (ELISA) for IgG and IgM against 11 oral microorganisms routinely isolated from such lesions. The results were analyzed statistically. Analysis of variance of …

A Study Of Transferable Antibiotic Resistance In Enteric Bacteria, Charles H. Regeski

Loma Linda University Electronic Theses, Dissertations & Projects

A group of 48 enteric bacteria was selected from a total of 170 at Loma Linda University Medical Center because of resistance to three or more antibiotics. They were examined to see if any of the antibiotic resistances were transferred by conjugation to either of two recipient bacteria. These were a restrictionless, antibiotic sensitive, azide resistant mutant of Escherichia coli K 12 designated E. coli 1228 and a similar phenotypic strain of Salmonella typhimurium LT2 designated LB 5000. Forty-three transferred one or more antibiotic resistances to either or both recipients, a frequency of 25.3% of the total bacteria and 89.6% …

A Study Of The Bacteriological Effectiveness Of Oral Thermometer Procedures In Three Selected Hospitals, Esther Mae Rose

Loma Linda University Electronic Theses, Dissertations & Projects

Because pathogens such as streptococcus and staphylococcus have been transferred in many hospitals, the source of the infections is of concern to doctors, nurses, and other medical personnel. As shown by the review of literature, good techniques are necessary to stop the spread of disease.

It was the purpose of this study to investigate one facet of patient safety by: (1) the culture of thermometers ready for use in three selected hospitals; (2) to determine the effectiveness of the Group, Individual, and Central Supply methods of disinfection currently practiced in the three selected hospitals.

The method for the experiment of …