Microbiology Commons^™

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 …

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 …

Cyanonews (Vol. 1, No. 2, December 1985), Jeff Elhai

CyanoNews

CyanoNews was a newsletter that served the cyanobacteriological community from 1985 to 2003, with content provided by readers (sort of a blog before there were blogs). The newsletter reported new findings from the lab, summaries of recent meetings (often provided by graduate students and post-docs entering the field), positions sought or available, life transitions, a compendium of recent cyanobacteria-related articles, and other items of interest to those who study cyanobacteria.

Cyanonews (Vol. 1, No. 1, July 1985), Jeff Elhai

CyanoNews

CyanoNews was a newsletter that served the cyanobacteriological community from 1985 to 2003, with content provided by readers (sort of a blog before there were blogs). The newsletter reported new findings from the lab, summaries of recent meetings (often provided by graduate students and post-docs entering the field), positions sought or available, life transitions, a compendium of recent cyanobacteria-related articles, and other items of interest to those who study cyanobacteria.

Dissection Of Microphage Activation Using T Cell Hybridoma Derived Lymphokines, William S. Futch Jr.

Theses and Dissertations

Macrophage phenotype/function can be modulated by various T-cell lymphokines (LK). The alteration of macrophage phenotype is a result of LK concentration, duration of exposure, and the level of macrophage activation when obtained from in vivo sources through elicitation by either sterile irritants or immune cellular mechanisms. In order to dissect macrophage activation into discrete signals T cell hybridomas were constructed by fusing HAT sensitive BW5147 cells with nylon-wool purified, con A stimulated T cells. The resulting T cell hybrids were screened for their ability to: (a) protect macrophages from the cytopathic effect of Naegleria; (b) induce class II MHC gene …

Enflagellation Of Naegleria Fowleri, Terry Wayne Woodworth

Theses and Dissertations

Organisms of the genus Naegleria differentiate from feeding, dividing amebae into temporary swimming flagellates when deprived of nutrients. Factors critical for enflagellation of the pathogenic species, N. fowleri, were delineated and optimal conditions established for evoking reproducible conversion of N.fowleri populations. N. fowleri enflagellation differed from that of N. gruberi in its dependence upon growth phase, population density during enflagellation and in the timing and extent of the conversion. N. fowleri amebae from stationary phase cultures grown at 37°C, washed free of medium and suspended in nutrient~free ameba saline, acquired flagella and converted to mature flagellates in a synchronous manner …

Solubilization And Partial Characterization Of An Activity Regulating Complement Activation From Membranes Of Raji And Tonsil Cells, Patricia L. Carlson

Theses and Dissertations

Complement is one of the major innate nonspecific mechanisms for host defense in serum. More than a dozen proteins have been isolated from serum which have a function in either the activation or regulation of complement action. Complement is similar to the coagulation sequence in that it comprises a number of precursor proenzymes in plasma that are sequentially cleaved to generate biologically and enzymatically active proteins.

The Role Of Retained Antigen As An Etiological Agent In Rheumatoid Arthritis, Patricia Liccardi Rice

Theses and Dissertations

The cause(s) of arthritis and many other connective tissue diseases are largely unknown. An infectious agent, either bacterial or viral, has not been unequivocally isolated. Theories on the pathogenesis of arthritis abound. Many of these theories implicate the immune system as the problem.

The early information on animal arthridites implicates retained bacterial cell wall antigens as the basis of the arthritis seen. How-ever, numerous types of antigens, both complex polymers and simple proteins, have been shown to persist in immune animals. The antigens persist in the lymph nodes and spleens playing a role in mediating antibody feedback mechanisms. Antigens also …

Efficacy Of Salinomycin On Infections Of Plasmodium Berghei In Male Icr Mice, Anthony Stephen Tokarz

Theses and Dissertations

The objective of this study was to determine whether or not salinomycin, a drug with proven effectiveness against intestinal sporozoan parasites, has any effect on the survival time of mice infected with P. berghei.

Antiviral Activity Of Peritoneal Exudate Cells Of Mice Against Infection With Herpes Simplex Virus Type 2, Margaret Byrd Mcgeorge

Theses and Dissertations

Within the past decade, there has been increasing evidence which suggests that herpes simplex virus type two (HSV-2) is associated with cervical carcinoma. Because cancer of the cervix ranks as the second most common malignant disease of women, with 35 thousand new cases and 10,000 deaths per year, further investigation is warranted to determine if there is a causal relationship (Goldberg, 1976). Currently, most of the evidence which correlates HSV-2 with cancer of the cervix has been, for the most part, indirect: (i) there is an increased incidence of cervical anaplasia in women with cytologically detectable genital herpes infection, (ii) …

Oncogenic Transformation By Herpes Simplex Virus, James Christian Burns

Theses and Dissertations

Many lines of evidence exist associating herpes simplex virus (HSV) with the development of carcinoma. Data from human studies includes seroepidemiologic studies of carcinoma patients and the localization of viral markers in human cancers. Experimental studies include in vitro transformation of cultured cells and viral induced alterations of host DNA. Much of this evidence is anecdotal or associative in nature and does not prove a cause and effect. The purpose of this research was to investigate the oncogenic potential of HSV type 2 (HSV-2) in vivo and in vitro.

An in vivo mouse model for lib carcinogenesis was designed to …

Intravenous Infection Of Mice With Naegleria Fowleri, Richard G. May

Theses and Dissertations

Primary amebic meningoencephalitis is a fatal disease of man caused by the free-living ameboflagelate Naegleria fowleri. In general, the victims have been active, healthy, young adults with a recent history of swimming or other fresh water-related activity. Infection with N. fowleri is apparently by way of nasal introduction of amebae-containing water. After nasal installation, electron microscopic and histopathologic studies with experimental animals reveal that amebae reside in the olfactory mucosa and then invade and migrate through the submucosal structures into the nerve plexuses. Amebae pass through pores of the cribiform plate and into the subarachnoid space. Subsequently, amebae invade the …

The Biological And Structural Characterization Of Transferable Bacteroides R Plasmids, Rodney A. Welch

Theses and Dissertations

In this literature review I will briefly describe the general biology of transferable antibiotic resistance in bacteria, the genetic elements involved (plasmids) and several specific plasmid associated phenotypes. This will be followed with a review of the general biology of Bacteroides, the information known concerning its plasmid reservoir and finally a review of the information documenting the emergence of transferable clindamycin resistance in Bacteroides. The latter aspect represents the central focus of research described in this thesis.

The Molecular Nature And Replication Of R Factor 222 In Proteus Mirabilis, Dennis Jon Kopecko

Theses and Dissertations

The molecular nature and replicative behavior of R factor 222 was examined in Proteus mirabilis . In deoxyribonucleic acid (DNA} from R+ P. mirabilis , R factor 222 was identified by CsCl density gradient centrifugation as 2 satellite DNA bands at densities corresponding to 50 and 58 moles percent guanine plus cytosine (% GC) . Replication of the 50 and 58% GC components of R factor 222 in P. mirabilis was analyzed during growth in the presence and absence of chloramphenicol (CAM} and after shifting exponentialand stationary- phase cells to conditions which inhibit host protein or DNA synthesis . CAM …

Studies Of Teratogenic Viruses: Minute Virus Of Mice And Colorado Tick Fever Virus, Robert Eldred Harris

Theses and Dissertations

Studies were conducted in DUB/ICR mice with minute virus of mice (MVM), a single stranded DNA virus, and Colorado tick fever (CTF) virus, a double stranded RNA Virus, to determine if CTF virus had teratogenic potential and to characterize further MVM and its teratogenic effects. MVM is a known teratogen, whereas CTF virus had never been investigated previously for teratogenic potential.

In characterization studies of MVM infectivity, the following were determined: (a) Rat embryo cells proved to be superior to six cell lines in assaying for MVM infectivity; (b) MVM infectivity could be inactivated with common laboratory disinfectants, ultraviolet radiation, …

Characterization Of Deoxyribonucleic Acid From Actinomycetes, Lynn William Enquist

Theses and Dissertations

Deoxyribonucleic acid (DNA) analyses were used to assess on a molecular level, the relationships among representatives of the genera Streptomyces, Nocardia and Mycobacterium. The methods developed in this study have been used for routine analysis of DNA from a large number of actinomycetes and have given reliable and reproducible data.

DNA isolated from various actinomycetes was characterized by buoyant density determinations in CsCl from which the mole fraction guanine plus cytosine (GC) content was calculated. All the streptomycete DNA preparations studied had buoyant densities in the range of 1.7287 to 1.7312 g cm^-3 which corresponded to GC compositions of …