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Full-Text Articles in Life Sciences

Identification Of Proteins Involved In Chloroplast Dna Replication, Matthew G. Lassen Dec 2004

Identification Of Proteins Involved In Chloroplast Dna Replication, Matthew G. Lassen

Theses and Dissertations

Chapter 1

Chloroplast nucleoids (ct-nucleoids) are DNA/protein complexes involved in compacting the chloroplast genome, and may play a role in regulating DNA replication. Ct-nucleoids were isolated from young soybean plants and separated by 2-D gel electrophoresis. Gel spots were excised and analyzed by MALDI-ToF mass spectrometry, resulting in several protein identifications. The proteins identified all have functions unrelated to DNA replication. While some of these proteins may be due to contamination, it is possible that some of these proteins are dual-functional, playing direct roles in the regulation of DNA replication.

Chapter 2

A 28 kDa soybean protein was isolated by …


Using A Bioluminescent Bacterial Bioreporter To Assess Iron Bioavailability In The Oceans, Cecile Elise Mioni Dec 2004

Using A Bioluminescent Bacterial Bioreporter To Assess Iron Bioavailability In The Oceans, Cecile Elise Mioni

Doctoral Dissertations

Recent improvements in modern analytical methods have considerably increased our understanding of Fe biogeochemistry in the Ocean. Compiled data have shown that Fe concentrations are low in most open ocean surface waters and that the bioavailability of this Fe is influenced by organic complexation. Of presumed biotic origin, the importance of this organic complexation to Fe availability remains to be elucidated. Unfortunately, current analytical tools do not allow for a linkage to be established between Fe speciation to Fe bioavailability.

To supplement chemical analyses, we have developed a bioanalytical tool: a heterotrophic bacterial bioluminescent reporter system that responds quantitatively to …


The Potential Role Of Ledgf/P75 In Prostate Cancer, Tracy Ruth Daniels Dec 2004

The Potential Role Of Ledgf/P75 In Prostate Cancer, Tracy Ruth Daniels

Loma Linda University Electronic Theses, Dissertations & Projects

The serum autoantibody repertoire from cancer patients is currently being exploited for the identification of tumor associated antigens (TAA) and the design of TAA arrays. Such arrays would facilitate autoantibody profiling and potentially aid in the serological diagnosis and prognosis of tumors. The goal of this study was to identify and characterize prostate-specific TAA. We observed that while the general frequency and titers of autoantibodies in PCa patients were relatively similar to those in matched controls, significant differences could be detected between the two groups in the autoantibody response to the lens epithelial-derived growth factor p75 (LEDGF/p75). LEDGF/p75 is a …


Enterotoxin B Subunit Lectins As Adjuvants For Improvement Of Mucosal Vaccine, Nak-Won Choi Dec 2004

Enterotoxin B Subunit Lectins As Adjuvants For Improvement Of Mucosal Vaccine, Nak-Won Choi

Loma Linda University Electronic Theses, Dissertations & Projects

In comparison with whole organism vaccines, subunit vaccines may be safer for immunization but may lack sufficient immunogenicity to provide complete immunity to the pathogen. To resolve this problem, bacterial and plant enterotoxin B subunit adjuvants containing a variety of receptor-binding properties were used to enhance the immunogenicity of rotavirus subunit vaccines. Enterotoxin B subunit adjuvants were employed to enhance protection against virus infection. Pentameric cholera toxin B subunit (CTB), shiga toxin-1 B subunit (STB) and monomeric ricin toxin B subunit (RTB) molecules were genetically linked to a 90 amino acid peptide from the simian rotavirus (SA11) nonstructural protein NSP4 …


Identifying The Signature Of The Natural Attenuation Of Mtbe In Groundwater Using Molecular Methods And "Bug Traps", Anita Eva Biernacki Aug 2004

Identifying The Signature Of The Natural Attenuation Of Mtbe In Groundwater Using Molecular Methods And "Bug Traps", Anita Eva Biernacki

Masters Theses

Natural attenuation through intrinsic bioremediation is the risk-based management approach commonly used for gasoline (BTEX) contamination sites. This approach has not yet been utilized for the fuel oxygenate methyl tertiary-butyl ether (MTBE). MTBE is more resistant to biodegradation than BTEX. MTBE is more abundant than benzene in oxygenated gasoline, has a greater water solubility than BTEX, and sorbs weakly to soil. These properties complicate developing a risk based management option to be implemented as easily as for BTEX. The purpose of this project is to contribute to a growing database containing information on MTBE contaminated sites nationwide with a variety …


Sol-Gel Encapsulation Of A Bioluminescent Bioreporter, Elizabeth F. Mitchell Aug 2004

Sol-Gel Encapsulation Of A Bioluminescent Bioreporter, Elizabeth F. Mitchell

Masters Theses

Genetic engineering has allowed for the development of a number of whole-cell bacterial bioreporters. In order for these cells to be used in certain devices and field applications, they must be maintained, and protected, but exposed to environmental conditions. One approach used to accomplish this goal is cellular encapsulation. The recent development of techniques to form inorganic matrices, in particular through the sol-gel process, displays promise as a system of encapsulation. The silica sol-gel process was originally designed for the fabrication of glass, and given that reactions are performed in standard lab conditions and room temperature, the process can be …


The Assessment Of Antibiotic Resistance And Detection Of Class 1 And Class 2 Integrons In Fecal Coliform Bacteria Isolated From The Triplett Creek Watershed, Rowan County, Kentucky, Tina Howard Ousley Jul 2004

The Assessment Of Antibiotic Resistance And Detection Of Class 1 And Class 2 Integrons In Fecal Coliform Bacteria Isolated From The Triplett Creek Watershed, Rowan County, Kentucky, Tina Howard Ousley

Morehead State Theses and Dissertations

A thesis presented to the faculty of the College of Science and Technology at Morehead State University in partial fulfillment of the requirements for the Degree of Master of Science by Tina Howard Ousley on July 15, 2004.


Mechanisms Of Oxidative Stress Resistance In Porphyromonas Gingivalis W83, Neal Antonio Johnson Jun 2004

Mechanisms Of Oxidative Stress Resistance In Porphyromonas Gingivalis W83, Neal Antonio Johnson

Loma Linda University Electronic Theses, Dissertations & Projects

Porphyromonas gingivalisis one of the most important bacterial etiological agents involved in adult periodontitis. It possesses several virulence factors which aid in its persistence in the periodontal pocket leading to the development of some systemic illnesses. As an anaerobe, P. gingivalismust employ mechanisms to avoid oxidative stress generated by reactive oxygen species during phagocytosis, or the occasional exposure to air. Presently, only three proteins with antioxidant enzymatic function have been identified as playing a role in oxidative stress resistance in P. gingivalis. In this study, attention was focused on the alkyl hydroperoxidase subunit C (ahpC)and bacterioferritin comigratory …


The Effects Of Fe On Plankton In Hnlc Regions Of The World’S Oceans, Melanie Lynn Eldridge May 2004

The Effects Of Fe On Plankton In Hnlc Regions Of The World’S Oceans, Melanie Lynn Eldridge

Doctoral Dissertations

Ecosystem-scale productivity in many marine environments has been demonstrated over the last 15 years to be regulated by the biological availability of iron (Fe). Increasingly, more attention has been focused on coastal upwelling regions, like those off the coasts of California and Peru, since these areas are responsible for a disproportionately high contribution to new global production. A mosaic of nutrient gradients exists in upwelling regions, making them ideal sites for studies of nutrient affects on aquatic microbial communities. Paradoxically, both the California and Peruvian upwelling regions have also been shown to be Fe-limited. The present studies took place in …


Methods For Detection Of Salmonella Spp., Parichaya Attaphongse May 2004

Methods For Detection Of Salmonella Spp., Parichaya Attaphongse

All Graduate Plan B and other Reports, Spring 1920 to Spring 2023

Worldwide concern about food safety and associated health costs is increasing, and Salmonella contamination of foods is one of the most important causes of foodborne disease outbreaks. Although conventional detection methods for Salmonella offer high sensitivity and low cost, they require many different steps and are very time consuming. Ideally, methods to detect Salmonella in foods should be rapid, provide high specificity and sensitivity, be cost-effective, and low labor-intensive. Many rapid tests have been developed to address these goals, including DNA-based tests such as nucleic acid hybridization and PCR, immunoassay-based tests such as ELISA, ELF A and immunomagnetic method, and …


The Effects Of Iron On Growth And Physiology Of The Cyanobacterium Microcystis Aeruginosa, Shannon Pedigo Efteland May 2004

The Effects Of Iron On Growth And Physiology Of The Cyanobacterium Microcystis Aeruginosa, Shannon Pedigo Efteland

Masters Theses

To determine the effects of iron on the growth of the cyanobacterium Microcystis aeruginosa, a series of growth and iron uptake experiments were conducted. Studies included the effects of iron and organic iron-binding chelators on batch cultures of known bacteria and on the natural community of Lake Erie, where blooms of M. aeruginosa have been documented since 1995. Results of growth rate studies under iron limitation suggest that M. aeruginosa uses an active, high-affinity transport system to acquire iron after a lag time at initial limitation. Further studies indicate that cells continue to take up nutrients and possibly metals, while …


Rapid Detection Of Salmonella Without Enrichment, Emily J. Harrington May 2004

Rapid Detection Of Salmonella Without Enrichment, Emily J. Harrington

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Salmonella is one of the leading foodborne pathogens causing illness today. Because of this, Salmonella rapid detection methods are under immense study for use in food. The traditional method, using the Food and Drug Administration- approved Bacterial Analytical Manual procedure, takes 4-6 days for Salmonella detection in food. Other rapid methods still take at least 16 h for detection due to their enrichment steps.

The hypothesis of this study was that the use of immobilized antibodies coupled with polymerase chain reaction (PCR) can be used for the rapid capture and detection of Salmonella spp. in food without the need for …


Development And Characterization Of Eukaryotic Biomimetic Liposomes, Bradley Jay Taylor May 2004

Development And Characterization Of Eukaryotic Biomimetic Liposomes, Bradley Jay Taylor

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

This study developed and characterized phospholipid vesicles, or liposomes, that mimic cell surfaces. Microemulsified liposomes contained biotinylated phosphatidylethanolamine, allowing them to be immobilized to avidin-coated glass. Laminin (LN), glycosphingolipids (GMl and GM3), and Escherichia coli's mechanosensitive channel of large conductance (EcoMscL) were embedded into liposome membranes. It was determined whether these embedded molecules exhibited their physiological roles of adhesion, cell recognition, and mechanosensation, respectively. Confocal laser scanning microscopy (CLSM) was employed to examine the interaction of fluorescently probed proteins, toxins, and bacteria with the immobilized microemulsified liposomes. Capture of individual and simultaneous multiple species of bacteria by GMl, GM3, …


Hormone Mediated Transport Of Calcium And Phosphate In Polarized Epithelial Cells, Tremaine M. Sterling May 2004

Hormone Mediated Transport Of Calcium And Phosphate In Polarized Epithelial Cells, Tremaine M. Sterling

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The effects of 1,25(OH)2D3, PTH and 25(OH)D3 on phosphate or calcium uptake were studied in cultured, adherent chick enterocytes over a period of 10 min after hormone addition. Time course studies of cells treated with 130 pM 1,25(OH)2D3 showed an increase in 32P uptake as early as 3 min. Similar studies with 65 pM bPTH(l1-34) resulted in an increase in 45Ca uptake only if the cells had been cultured in serum. (OH)D3, which is not firmly established as an active metabolite of vitamin D, was shown to increase …


Fabrication, Characterization, And Chemical Sensing Of Silicon Dioxide Microcantilevers, Yanjun Tang Apr 2004

Fabrication, Characterization, And Chemical Sensing Of Silicon Dioxide Microcantilevers, Yanjun Tang

Doctoral Dissertations

The objective of this work is to design and fabricate an advanced silicon dioxide microcantilever sensor and to investigate chemical and biological sensing by microtechnology.

Microcantilever sensor technology has many advantages including fast response time, lower cost of fabrication, the possibility of sensor arrays with small overall dimensions, the ability to explore microenvironments, and improved portability for field applications. For all of these advantages, microcantilever chemical and biological sensors have drawn more and more attention.

So far, all other microcantilevers were designed and fabricated for AFM applications. We developed a novel SiO2 microcantilever especially for chemical and biological sensor applications. …


The Biological Burden Of Antibiotic Resistance In Staphylococcus Aureus, Natasha Samantha Dean Mar 2004

The Biological Burden Of Antibiotic Resistance In Staphylococcus Aureus, Natasha Samantha Dean

Loma Linda University Electronic Theses, Dissertations & Projects

Antibiotic resistance is a major problem. Resistance is often mediated by genes on bacterial plasmids and dissemination of resistance is commonly achieved by plasmid transfer. The mechanisms of resistance that are presently understood suggest that resistance is energetically costly. If this is generally true, resistance would reduce the fitness of cells in the absence of antibiotics. We examined the hypothesis that resistance reduces the fitness of microorganism and requires continuous selection to be maintained. To test this hypothesis, we measured the effects of plasmid-borne resistance genes on cell growth by comparing the growth rates of Staphylococcus aureus with and without …


Detection Of Bacteria To Dental Tissue By Low-Light Imaging, G-Hong Robert Hsu Mar 2004

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 Immune Response And Gene Expression Profiling In Crohn's Dise, Claudia Romero Jan 2004

Cellular Immune Response And Gene Expression Profiling In Crohn's Dise, Claudia Romero

Electronic Theses and Dissertations

Despite the chronic debate in the etiology of crohn's disease (cd), a debilitating inflammatory bowel disease (ibd) closely related to ulcerative colitis (uc), an emerging interest in a possible mycobacterial role has been marked. Granuloma and pathologic manifestations in cd resemble aspects found in tuberculosis, leprosy and paratuberculosis. The latter, a chronic enteritis in cattle, goat, sheep and primates, which is similar to human enteritis, also known as cd, is caused by a fastidious, slow growing mycobacterium avium subspecies paratuberculosis (map). Due to the similarities between cd and paratuberculosis, a mycobacterial cause in cd has been proposed. Recent discovery of …


Pathobiology Of Mycobacteria In Striped Bass (Morone Saxatilis), David T. Gauthier Jan 2004

Pathobiology Of Mycobacteria In Striped Bass (Morone Saxatilis), David T. Gauthier

Dissertations, Theses, and Masters Projects

Striped bass (Morone saxatilis) in Chesapeake Bay, USA, are experiencing an epizootic of mycobacteriosis. This disease, caused by bacteria in the genus Mycobacterium, causes granulomatous lesions of the skin and viscera. Diseased fish are often emaciated, and fish with skin lesions may be significantly disfigured. The overall goal of this work was to examine aspects of the pathobiology of mycobacteria in striped bass via laboratory exposure studies and cellular assays. Striped bass were injected intraperitoneally with a sublethal dose of Mycobacterium marinum, M. shottsii, or M. gordonae and sampled for histology and bacteriology at regular intervals to 45 weeks post-injection …


Extracullular Atp Regulates Il-1beta Release From Microglial Cells Via Purinergic Receptor After In Vitro Trauma, Chengya Liang Jan 2004

Extracullular Atp Regulates Il-1beta Release From Microglial Cells Via Purinergic Receptor After In Vitro Trauma, Chengya Liang

Electronic Theses and Dissertations

Traumatic brain injury (TBI) induces a state of microglialactivation, which includes upregulation of macrophage functions and release inflammatory mediators such as certain inflammatory cytokines. Current literature suggests that interleukin-1Beta is an important cytokine mediator, which is dramatically increased after brain injury. Previous studies indicate that ATP is released by traumatically injured astrocytes and serves as a cell-to-cell mediator through purinergic receptors after in vitro injury. However, the mechanism of interleukin-1Beta release after traumatic brain injury remains poorly defined and is difficult to study using in vivo models. Using an in vitro model for traumatic brain injury (cell strain or stretch), …


Evaluation Of Immunogenicity Of Transgenic Chloroplast Derived Protect, Vijay Koya Jan 2004

Evaluation Of Immunogenicity Of Transgenic Chloroplast Derived Protect, Vijay Koya

Electronic Theses and Dissertations

Anthrax, a fatal bacterial infection is caused by Bacillus anthracis, a gram-positive, spore forming, capsulated, rod shaped organism. Centers for Disease Control (CDC) lists anthrax as Category A biological agent due to its severity of impact on human health, high mortality rate, acuteness of the disease and potential for delivery as a biological weapon. The currently available human vaccine in the United States (AVA anthrax vaccine adsorbed) is prepared from Alum adsorbed formalin treated supernatant culture of toxigenic, non-encapsulated strain of Bacillus anthracis with the principle component being protective antigen (PA83). Evaluation of anthrax vaccine given to nearly 400,000 US …


Survival Of Mycobacterium Avium Subspecies Paratuberculosis In The Pol, John Rumsey Jan 2004

Survival Of Mycobacterium Avium Subspecies Paratuberculosis In The Pol, John Rumsey

Electronic Theses and Dissertations

Mycobacterium avium subspecies paratuberculosis (map) is an intracellular pathogen that is known to parasitize macrophages and monocytes. Map infiltrates gastrointestinal tract host tissue where it is the known etiological agent of johne's disease in ruminants and implicated in the etiology of crohn's disease in humans. Map's ability to survive within macrophages enables it to disseminate throughout the rest of the host, possibly infecting other circulating blood leukocytes. In this study, the survival and fate of map strain atcc 43015 (human isolate) following phagocytosis was determined using in vitro murine macrophage cell line j774a.1 and polymorphonuclear cells (pmnc's) from five crohn's …


Evaluation Of The Host Range Of Polyvalent Staphylococcal Bacteriophages To Control Mrsa (Staphylococcus Aureus) From Irish Hospitals, Mohamed Farag M. Elbreki Jan 2004

Evaluation Of The Host Range Of Polyvalent Staphylococcal Bacteriophages To Control Mrsa (Staphylococcus Aureus) From Irish Hospitals, Mohamed Farag M. Elbreki

Theses

This study describes firstly, the assembly of a collection of a varied spectrum of staphylococci which can be used to test the efficacy of bacteriophages for the biocontrol of problematic members of this genus. The collection assembled includes a variety of multi-antibiotic resistant MRSA (methicillin resistant S. aureus) strains, hVRSA (hetero vancomycin resistant S. aureus), VRSA and also teicoplenin resistant isolates. It also included a broad range of species of coagulase-negative {non-aureus) staphylococci including S. caprea, S. haemolyticus, S. saprophyticus, S. epidermidis, S. chromogenes, S. capitis, S. hominins and S. hyicus. All strains were characterized by morphology on Baird Parker, …


An Investigation Of Dissolved Organic Matter In A Shallow Coastal Bay Subject To Aureococcus Anophagefferens Blooms, Jean-Paul Simjouw Jan 2004

An Investigation Of Dissolved Organic Matter In A Shallow Coastal Bay Subject To Aureococcus Anophagefferens Blooms, Jean-Paul Simjouw

OES Theses and Dissertations

Aureococcus anophagefferens, the pelagophyte responsible for brown tide blooms, was identified in Chincoteague Bay in 1997 and has “bloomed” there since at least 1998. Aureococcus anophagefferens is capable of using dissolved organic nitrogen (DON) and dissolved organic carbon (DOC) substrates to support growth, and this utilization is hypothesized to give the organism a competitive advantage relative to other phytoplankton when inorganic nutrient concentrations are low or depleted. Because previous studies suggest dissolved organic matter (DOM) is important in initiating and sustaining brown tide blooms, a field study of the variations in DOC concentration and DOM composition was performed at …


Dynamics Of The Host-Parasite Interaction: In Vitro Correlates Of Crassostrea-Induced Modulation Of Perkinsus Marinus Function, Christopher G. Earnhart Jan 2004

Dynamics Of The Host-Parasite Interaction: In Vitro Correlates Of Crassostrea-Induced Modulation Of Perkinsus Marinus Function, Christopher G. Earnhart

Dissertations, Theses, and Masters Projects

Perkinsus marinus is an alveolate protozoan parasite of the eastern oyster (Crassostrea virginica) which is responsible for much of the decline in United States oyster populations. Perkinsus marinus can be cultured in vitro, but is rapidly attenuated in the process. Supplementation of a protein-free medium with oyster products altered proliferation, changed protease expression in the parasite extracellular products (ECP), induced morphological forms typically seen in vivo, and partially reversed parasite attenuation. Supplements derived from dissected oyster tissues were used to determine if these changes could be differentially elicited. These supplements, with the exception of adductor muscle, reduced proliferation. Whole oyster …


Do Sulfide-Oxidizing Bacteria Produce Light?, Rachel Elizabeth Ann Horak Jan 2004

Do Sulfide-Oxidizing Bacteria Produce Light?, Rachel Elizabeth Ann Horak

Dissertations, Theses, and Masters Projects

No abstract provided.


Plumage As A Habitat For Bacilli, Justine M. Whitaker Jan 2004

Plumage As A Habitat For Bacilli, Justine M. Whitaker

Dissertations, Theses, and Masters Projects

No abstract provided.