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Articles 1 - 11 of 11

Full-Text Articles in Microbiology

Campylobacter Ureolyticus: An Emerging Gastrointestinal Pathogen?, Susan Bullman, Daniel Corcoran, James O'Leary, Brigid Lucey, Deirdre Byrne, Roy D. Sleator Dec 2010

Campylobacter Ureolyticus: An Emerging Gastrointestinal Pathogen?, Susan Bullman, Daniel Corcoran, James O'Leary, Brigid Lucey, Deirdre Byrne, Roy D. Sleator

Department of Biological Sciences Publications

A total of 7194 faecal samples collected over a 1-year period from patients presenting with diarrhoea were screened for Campylobacter spp. using EntericBios, a multiplex-PCR system. Of 349 Campylobacter-positive samples, 23.8% were shown to be Campylobacter ureolyticus, using a combination of 16S rRNA gene analysis and highly specific primers targeting the HSP60 gene of this organism. This is, to the best of our knowledge, the first report of C. ureolyticus in the faeces of patients presenting with gastroenteritis and may suggest a role for this organism as an emerging enteric pathogen.


Study Of Population Diversity Of Toxoplasma Gondii, Debashree Majumdar Dec 2010

Study Of Population Diversity Of Toxoplasma Gondii, Debashree Majumdar

Masters Theses

Toxoplasma gondii, the causal agent of toxoplasmosis, is an important water and food borne protozoan parasite. T. gondii was previously shown to have a distinct clonal population structure composed of Type I, II and III lineages in North America and Europe. But more recent studies demonstrated high diversity in South America. In the present project we have conducted an intensive study of the population diversity of T. gondii and surveyed the extent of genetic variation among natural T. gondii isolates on a global scale in order to better understand the population dynamics and pathogenesis of this parasite. To this …


Deletion Of The Cel48s Cellulase From Clostridium Thermocellum, Daniel G. Olson, Shital A. Tripathi, Richard J. Giannone, Jonathan Lo, Nicky C. Caiazza, David A. Hogsett, Robert L. Hettich, Adam M. Guss, Genia Dubrovsky, Lee R. Lynd Oct 2010

Deletion Of The Cel48s Cellulase From Clostridium Thermocellum, Daniel G. Olson, Shital A. Tripathi, Richard J. Giannone, Jonathan Lo, Nicky C. Caiazza, David A. Hogsett, Robert L. Hettich, Adam M. Guss, Genia Dubrovsky, Lee R. Lynd

Dartmouth Scholarship

Clostridium thermocellum is a thermophilic anaerobic bacterium that rapidly solubilizes cellulose with the aid of a multienzyme cellulosome complex. Creation of knockout mutants for Cel48S (also known as CelS, S(S), and S8), the most abundant cellulosome subunit, was undertaken to gain insight into its role in enzymatic and microbial cellulose solubilization. Cultures of the Cel48S deletion mutant (S mutant) were able to completely solubilize 10 g/L crystalline cellulose. The cellulose hydrolysis rate of the S mutant strain was 60% lower than the parent strain, with the S mutant strain also exhibiting a 40% reduction in cell yield. The cellulosome produced …


Development Of Pyrf-Based Genetic System For Targeted Gene Deletion In Clostridium Thermocellum And Creation Of A Pta Mutant, Shital A. Tripathi, Daniel G. Olson, D. Aaron Argyros, Bethany B. Miller, Trisha F. Barrett, Daniel M. Murphy, Jesse D. Mccool, Anne K. Warner, Vineet B. Rajgarhia, Lee R. Lynd, David A. Hogsett, Nicky C. Caiazza Aug 2010

Development Of Pyrf-Based Genetic System For Targeted Gene Deletion In Clostridium Thermocellum And Creation Of A Pta Mutant, Shital A. Tripathi, Daniel G. Olson, D. Aaron Argyros, Bethany B. Miller, Trisha F. Barrett, Daniel M. Murphy, Jesse D. Mccool, Anne K. Warner, Vineet B. Rajgarhia, Lee R. Lynd, David A. Hogsett, Nicky C. Caiazza

Dartmouth Scholarship

We report development of a genetic system for making targeted gene knockouts in Clostridium thermocellum, a thermophilic anaerobic bacterium that rapidly solubilizes cellulose. A toxic uracil analog, 5-fluoroorotic acid (5-FOA), was used to select for deletion of the pyrF gene. The ΔpyrF strain is a uracil auxotroph that could be restored to a prototroph via ectopic expression of pyrF from a plasmid, providing a positive genetic selection. Furthermore, 5-FOA was used to select against plasmid-expressed pyrF, creating a negative selection for plasmid loss. This technology was used to delete a gene involved in organic acid production, namely pta, which encodes …


An Analysis Of Global Gene Expression Resulting From Exposure To Energetic Materials, Vernon L. Mcintosh Jr. Aug 2010

An Analysis Of Global Gene Expression Resulting From Exposure To Energetic Materials, Vernon L. Mcintosh Jr.

Doctoral Dissertations

AN ANALYSIS OF GLOBAL GENE EXPRESSION RESULTING FROM EXPOSURE TO ENERGETIC MATERIALS

A Dissertation

Presented for the Doctor of Philosophy Degree

University of Tennessee, Knoxville

VERNON LASHAWN MCINTOSH JR.

August 2010

Dedication

This dissertation is dedicated to my family. My mother and father Debra and Vernon McIntosh instilled in me the respect for academic excellence and the drive maximize my potential. Early on, my younger brother Kyle started showing signs of a shared interest in biology thus my desire to be a positive role model for him kept me motivated. Last but certainly not least, my loving wife and best …


Electrically Mediated Delivery Of Plasmid Dna To The Skin, Using A Multielectrode Array, Richard Heller, Yolmari Criz, Loree C. Heller, Richard A. Gilbert, Mark J. Jaroszeski Mar 2010

Electrically Mediated Delivery Of Plasmid Dna To The Skin, Using A Multielectrode Array, Richard Heller, Yolmari Criz, Loree C. Heller, Richard A. Gilbert, Mark J. Jaroszeski

Bioelectrics Publications

The easy accessibility of skin makes it an excellent target for gene transfer protocols. To take full advantage of skin as a target for gene transfer, it is important to establish an efficient and reproducible delivery system. Electroporation is a strong candidate to meet this delivery criterion. Electroporation of the skin is a simple, direct, in vivo method to deliver genes for therapy. Previously, delivery to the skin was performed by means of applicators with relatively large distances between electrodes, resulting in significant muscle stimulation and pain. These applicators also had limitations in controlling the directionality of the applied field. …


Quantitative Pcr Assay For Mycobacterium Pseudoshottsii And Mycobacterium Shottsii And Application To Environmental Samples And Fishes From The Chesapeake Bay, D. T. Gauthier, K. S. Reece, J. Xiao, M. W. Rhodes, H. I. Kator, R. J. Latour, C. F. Bonzek, J. M. Hoenig, W. K. Vogelbein Jan 2010

Quantitative Pcr Assay For Mycobacterium Pseudoshottsii And Mycobacterium Shottsii And Application To Environmental Samples And Fishes From The Chesapeake Bay, D. T. Gauthier, K. S. Reece, J. Xiao, M. W. Rhodes, H. I. Kator, R. J. Latour, C. F. Bonzek, J. M. Hoenig, W. K. Vogelbein

Biological Sciences Faculty Publications

Striped bass (Morone saxatilis) in the Chesapeake Bay are currently experiencing a very high prevalence of mycobacteriosis associated with newly described Mycobacterium species, Mycobacterium pseudoshottsii and M. shottsii. The ecology of these mycobacteria outside the striped bass host is currently unknown. In this work, we developed quantitative real-time PCR assays for M. pseudoshottsii and M. shottsii and applied these assays to DNA extracts from Chesapeake Bay water and sediment samples, as well as to tissues from two dominant prey of striped bass, Atlantic menhaden (Brevoortia tyrannus) and bay anchovy (Anchoa mitchilli). Mycobacterium …


Electric Pulses To Prepare Feeder Cells For Sustaining And Culturing Of Undifferentiated Embryonic Stem Cells, Lauren M. Browning, Tao Huang, Xiao-Hong Nancy Xu Jan 2010

Electric Pulses To Prepare Feeder Cells For Sustaining And Culturing Of Undifferentiated Embryonic Stem Cells, Lauren M. Browning, Tao Huang, Xiao-Hong Nancy Xu

Chemistry & Biochemistry Faculty Publications

Current challenges in embryonic-stem-cell (ESC) research include inability of sustaining and culturing of undifferentiated ESCs over time. Growth-arrested feeder cells are essential to the culture and sustaining of undifferentiated ESCs, and they are currently prepared using gammaradiation and chemical inactivation. Both techniques have severe limitations. In this study, we developed a new, simple and effective technique (pulsed-electric-fields, PEFs) to produce viable growth-arrested cells (RTS34st) and used them as high-quality feeder cells to culture and sustain undifferentiated zebrafish ESCs over time. The cells were exposed to 25 sequential 10- nanosecond-electric-pulses (10nsEPs) of 25, 40 and 150 kV/cm with 1s pulse interval, …


Plasmid Injection And Application Of Electric Pulses Alter Endogenous Mrna And Protein Expression In B16.F10 Mouse Melanomas, L. C. Heller, Y. L. Cruz, B. Ferraro, H. Yang, R. Heller Jan 2010

Plasmid Injection And Application Of Electric Pulses Alter Endogenous Mrna And Protein Expression In B16.F10 Mouse Melanomas, L. C. Heller, Y. L. Cruz, B. Ferraro, H. Yang, R. Heller

Bioelectrics Publications

The application of electric pulses to tissues causes cell membrane destabilization, allowing exogenous molecules to enter the cells. This delivery technique can be used for plasmid gene therapy. Reporter gene expression after plasmid delivery with eight representative published protocols was compared in B16.F10 mouse melanoma tumors. This expression varied significantly based on the pulse parameters utilized for delivery. To observe the possible influence of plasmid injection and/or pulse application on endogenous gene expression, levels of stress-related mRNAs 4 and 24 h after delivery were determined by PCR array. Increases in mRNA levels for several inflammatory chemokines and cytokines were observed …


Isolation And Molecular Characterization Of Mycobacterium Avium Subsp. Paratuberculosis In Ireland, Pierre Emmanuel Douarre Jan 2010

Isolation And Molecular Characterization Of Mycobacterium Avium Subsp. Paratuberculosis In Ireland, Pierre Emmanuel Douarre

Theses

MAP is a proven animal pathogen causing Johne's disease, one of the most widespread and economically important diseases of ruminants. Since 1992 and the opening of the European market, the prevalence of MAP in Ireland has increased considerably. Improvements in diagnostic strategies for Ireland and elsewhere are urgently required. MAP infects a wide host range and has emerged as a potential threat to human health and has been associated with Crohn's disease. The control of paratuberculosis infection requires a better understanding of the genetic diversity of the pathogen. The objective of this study was to isolate and characterize this enteric …


Increased Perfusion And Angiogenesis In A Hindlimb Ischemia Model With Plasmid Fgf-2 Delivered By Noninvasive Electroporation, B. Ferraro, Y. L. Cruz, M. Baldwin, D. Coppola, R. Heller Jan 2010

Increased Perfusion And Angiogenesis In A Hindlimb Ischemia Model With Plasmid Fgf-2 Delivered By Noninvasive Electroporation, B. Ferraro, Y. L. Cruz, M. Baldwin, D. Coppola, R. Heller

Bioelectrics Publications

Gene therapy approaches delivering fibroblast growth factor-2 (FGF-2) have shown promise as a potential treatment for increasing blood flow to ischemic limbs. Currently, effective noninvasive techniques to deliver plasmids encoding genes of therapeutic interest, such as FGF-2, are limited. We sought to determine if intradermal injection of plasmid DNA encoding FGF-2 (pFGF) followed by noninvasive cutaneous electroporation (pFGFE+) could increase blood flow and angiogenesis in a rat model of hindlimb ischemia. pFGFE+ or control treatments were administered on postoperative day 0. Compared to injection of pFGF alone (pFGFE-), delivery of pFGFE+ significantly increased FGF-2 expression for 10 days. Further, the …