Organisms Commons^™

Microorganisms Associated With The Carapace And Plastron Of Aquatic Turtles (Pseudemys Concinna And Trachemys Scripta) In Southwestern Arkansas, Renn Tumlison, Sharon Clark

Journal of the Arkansas Academy of Science

No abstract provided.

Experimental Peri-Implant Tissue Breakdown In Rhesus Monkeys, Oliver Hanisch

Loma Linda University Electronic Theses, Dissertations & Projects

The aim of this investigation was to characterize peri-implant tissue breakdown following ligature-induced plaque accumulation around osseointegrated implants in the rhesus monkey. Two hydroxyapatite-coated cylindrical implants were inserted bilaterally in the second premolar and first molar region of both mandible and maxilla in four non-human primates (Macaca mulatto). The implants were left submerged to osseointegrate for one year. Eight weeks after healing abutment connection, a two-month plaque control program was initiated. At the end of this period, clinical and radiographic recordings were carried out, and peri-implant subgingival microbial samples were obtained (baseline). Subsequently, cotton ligatures were placed around …

Signal Transduction In Bacterial Chemotaxis, Edward Heath Rowsell

Loma Linda University Electronic Theses, Dissertations & Projects

This study investigated the site of ATP utilization in the signal transduction pathway of bacterial chemotaxis and localized the point of convergence of a methylation-independent system of chemotaxis with the methylation-dependent system. The identity of the signal originating from the phosphotransferase system was investigated by substituting the fructose-inducible HPr-like protein FPr for HPr in transport and chemotaxis. In addition, a novel chemoattractant, glycerol, was identified for Salmonella typhimurium. Histidine-auxotrophic S. typhimurium strains ST23 (hisF) and ST171 (hisF cheB) were depleted for ATP. The times required for the bacteria to adapt to a step increase in serine, …

A Physical Map Of The Klebsiella Pneumoniae M5a1 Genome, Alexandrine Randriamahefa

Loma Linda University Electronic Theses, Dissertations & Projects

Klebsiella pneumoniae is an enteric opportunistic pathogen which commonly causes pulmonary, urinary tract and kidney infections. It has also been widely used for the study of nitrogen fixation. In this study, a macrorestriction map of K. pneumoniae M5a1 chromosomal DNA was constructed using pulsed field gel electrophoresis (PFGE) and Southern hybridization techniques. The genome DNA was digested with two rare cutting restriction enzymes (XbaI and BlnI) and the genome size was estimated from the sum of the fragment sizes as 5,121 Kb (+2.8%). A tentative order of fragments was deduced using Southern hybridization with purified restriction fragments. …

Laccase Production By Chaetomium Elatum, A Soft-Rot Fungus, Wilson H. Howe, Joyce M. Hardin

Journal of the Arkansas Academy of Science

Though enzymes responsible for rotting wood have been studied for some time, the enzymes and enzymatic systems responsible for breaking down lignin have only begun to be discovered. The lignin-degrading enzymes produced by soft-rot fungi, in particular, have not been sufficiently studied. The present study presents evidence that the enzyme called laccase, known to be associated with lignin biodegradation, is produced by the species Chaetomium elatum, a soft-rot fungus. Cerrena unicolor, a positive control, and Chaetomium elatum were grown in culture. These species were tested for the presence of laccase using syringaldazine as a chromogenic substrate. As expected, Cerrena unicolor …

Aerotaxis In Bacillus Subtilis, Laurence Samuel Wong

Loma Linda University Electronic Theses, Dissertations & Projects

B. subtilis, like Escherichia coli and Salmonella typhimurium, responded to a step increase in oxygen concentration by swimming smoothly (~ 35 s duration) and to a decrease in oxygen by tumbling. In a spatial gradient of oxygen in liquid media, a band of cells congregated near the air interface. Aerotaxis required a functioning respiratory chain. Adaptation of B. subtilis, E. coli and S. typhimurium to media containing amino acids requires methylation of receptors/methyl-accepting chemotaxis proteins. Adaptation to oxygen and phosphotransferase sugar substrates in B. subtilis was dependent on methylation, unlike similar adaptation in E. coli and S. typhimurium. …

The Distribution And Occurrence Of Aerobic Heterotrophic Antimicrobic-Producing Bacteria Isolated From The Lower Chesapeake Bay, Linda Lea Gilmer

Biological Sciences Theses & Dissertations

Three different estuarine microenvironments in the lower Chesapeake Bay were investigated for the occurrence and geographical distribution of antimicrobic-producing bacteria. Samples were taken from the water column, fish skin, and algal surfaces. A total of 1472 bacterial isolates were assayed for antimicrobial activity against fungal, Gram-negative and Gram-positive bacterial test organisms. Of the total bacterial isolates assayed, 5. 2% were active antimicrobic producers. Algal surf aces were shown to have a higher incidence of antimicrobic-producing bacteria than the water column or fish skin. No antimicrobic activity was demonstrated by bacteria isolated from the flounder fish skin. The majority of the …

Role Of Endophytes In Tall Fescue, E. L. Piper, C. P. West

Journal of the Arkansas Academy of Science

Tall fescue (Festuca arundinacea Schreb.) is the most commonly grown cool season grass used for pastures in Arkansas. Most tall fescue contains a fungal endophyte (Acremonium coenophialum Morgan-Jones & Gams), which causes fescue toxicosis in livestock and costs cattle producers millions of dollars annually in lost production. Endophyte presence is known to reduce wild mammal populations in areas where tall fescue is prevalent. The endophyte spends its entire life cycle within the plant and is transmitted through the seed. The association is mutualistic with the plant providing nutrients for the endophyte and the endophyte conferring drought, insect, and nematode resistance …

Development Of Periapical Lesions In Immunosuppressed Rats, Phillip A. Waterman Jr.

Loma Linda University Electronic Theses, Dissertations & Projects

The pathogenesis of periapical lesions is the interaction of the oral flora with the existing host defenses. The role of bacteria has been established in endodontic disease but the contribution of the host defenses in periapical lesion formation is less clear. The purpose of this study was to compare periapical lesion development in immunosuppressed rats with that in normal rats. Thirty-five, eight-week old Sprague-Dawley rats were equally divided into seven groups. Groups 1, 2, and 3 were given weekly injections of Cytoxan, an immunosuppressive agent. Groups 4, 5, and 6 received no immunosuppressive therapy. Group 7 served as a control, …

The Influence Of Antimicrobial Use On Bacterial Resistance, James T. Griffith

Walden Dissertations and Doctoral Studies

Antimicrobial resistance is becoming an increasingly serious problem accompanied by relatively few studies examining the relationship between use and resistance. The present study undertakes a twenty year analysis of antimicrobial production and factors affecting antimicrobial use for a particular microorganism (Stp. faecalis)/antimicrobial agent (Cephalothin) combination. The period is inclusive of the market introduction of the agent and considerate of prescribing practices to the present time. The accumulated data reveal that there is indeed a relationship between total drug availability (medicinal, agricultural) and increased antimicrobial resistance. The data also suggest that national (or global) use changes would likely have a long …

Biodegradation Of Crude Oil By Marine Higher Fungi, Brian J. Dyer

Biological Sciences Theses & Dissertations

Four experiments were performed to determine the ability of marine higher fungi to grow in and degrade crude oil. Eight species, previously determined to be hydrocarbonoclastic, were grown in artificial sea water medium (ASM) and southern Louisiana crude oil. The dry mycelial weights were measured and consumption of crude oil was measured gravimetrically. The two species with the best growth, Corollospora maritima and Zalerion maritimum, were grown in ASM containing crude oil spiked with three known hydrocarbons. To this was added glucose (0.15%) and incubated 49 days to test for possible cometabolism of hydrocarbons. Hydrocarbons remaining in the growth …

Revival Of Metabolism In Rehydrated Marasmius Oreades, Lorie J. Warren

Honors Theses, 1963-2015

Mushrooms from the genus Marasmius have the ability to revive -- viz., dried specimens regain their original shape when moistened. The purpose of this study was to determine if the basidiocarps are metabolically active upon revival or whether they simply absorb moisture like a sponge. The reduction of tetrazolium chloride to a red, water-insoluble formazan pigment was used as a measure of respiratory activity. Basidiocarp samples were incubated in a phosphate buffer containing 1% tetrasolium chloride. After a suitable period, the samples were extracted with MeOH to remove any formazan pigment and the absorbance measured at 530 nm. Fresh M. …

First Evidence Of Plague (Yersinia Pestis) In Nebraska Is Found In Panhandle Predators, Dallas Virchow, Wayne L. Kramer, Charles S. Brown, Scott E. Hygnstrom, Alan M. Barnes

Transactions of the Nebraska Academy of Sciences and Affiliated Societies

In September, 1992, plague (Yersinia pestis) antibody was found in the blood of a coyote (Canis latrans) (1:128 titer) and a badger (Taxidea taxus) (1:2048 titer) taken near a suspect black-tailed prairie dog (Cynomys ludovicianus) town in Sioux County. However, a 1989-1991 survey of 96 coyotes taken from nine Nebraska Panhandle counties demonstrated no plague antibodies. Passive hemagglutination tests of Nobuto blood-sampling paper proved useful to quickly survey a predator population that is distributed across a broad geographic area.

Evaluation Of Aposphaeria Amaranthi As A Bioherbicide For Pigweed (Amaranthus Spp.), A. S. Mintz, G. J. Weidmann

Journal of the Arkansas Academy of Science

Studies were conducted to determine the potential of the fungus, Aposphaeria amaranth!, as a bioherbicide for pigweeds (Amaranthus spp.). Experiments to establish the environmental parameters necessary for control of tumble pigweed (A. albus) demonstrated that an 8-hr dew period was sufficient for control of seedlings with four to six leaves, and that temperatures ranging from 20 to 28 C were conducive for disease development. Conidial concentrations as lowas 1x 10s conidia per ml also were sufficient for plant mortality. Host range tests demonstrated pathogenicity of A. amaranthi to several other species of Amaranthus, including biotypes resistant to triazine herbicides. Disease …

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 …

Vocal Recognition Of Pups By Mother Mexican Free-Tailed Bats, Tadarida Brasiliensis Mexicana, Jonathan P. Balcombe

Sentience Collection

The ability of Mexican free-tailed bat mothers and pups to recognize vocalizations of their presumptive kin (pup isolation calls and mother echolocation calls, respectively) was tested using playbacks of recorded calls. Captive individuals were presented with calls of two bats, one presumptive kin and the other a stranger, from opposite sides of a circular wire arena. Response was determined by amount of time spent on each side of the arena, time spent in contact with a cloth bat model in front of each speaker, and number of separate contacts with each model. For the latter two measures, mothers showed a …

Biological Control Of Doublegee, Dane Panetta

Journal of the Department of Agriculture, Western Australia, Series 4

Doublegee (Emex australis) is one of the worst agricultural weeds in Western Australia. To date, however, biological control of this weed has proved elusive. Multiple releases of two weevils which attack doublegee have not led to insect establishment. For one of these species, further research has shown that doublegee control would probably not be achieved in the wheatbelt even if insect establishment were enhanced by growing its host during the summer months. A joint Western Australian Department of Agriculture/ CSIRO project is investigating the virulence and host specificity of an undescribed South African species o/Phomopsis fungus. Should this pathogen prove …

Bulletin 4133 - Fungal Diseases Of Pasture Legumes In Western Australia, M. J. Barbetti

Bulletins 4000 -

Subterranean clover (Trifolium subterraneum L.) is the most important annual pasture legume in Western Australia, forming the basis of some 6.5 million ha of annual pastures. The success of subterranean clover may be attributed to its ability to increase soil fertility as a consequence of nitrogen fixed, to withstand heavy grazing, to control soil erosion and, with some cultivars, to tolerate waterlogging. Fungal diseases have been a major limitation to the productivity of subterranean clover, affecting both the amount of plant matter and the quantity of seed produced.

Annual medic (Medicago spp., in particular M. polymorpha L.) is also an …

Effect Of Inhibitors Of Arachidonic Acid Metabolism On Corneal Neovascularization In The Rat, W. L. Haynes, A. D. Proia, G. K. Klintworth

Osteopathic Medicine, Jerry M. Wallace School of

No abstract provided.

The Composition And Concentrations Of Cyanobacteria In The North Landing River, Virginia And Upper Currituck Sound, North Carolina, Sonja E. Midgette

Biological Sciences Theses & Dissertations

A 12 month study of cyanobacteria composition and concentrations in the North Landing River and upper Currituck Sound was conducted from March 1986 to February 1987. Epifluorescence microscopy and the fluorochrome proflavin were used to determine cell concentrations and vertical, station to station and seasonal distribution of these cells. Cyanobacterial assemblage patterns were coupled with pH, temperature, salinity and water transparency readings.

Cyanobacteria were found to be a persistent and prolific phytoplankton component of both the river and upper sound. For a comparison of vertical distribution for each station, an analysis of variance for. two groups of equal size was …

The Amino Acid Sequence Of The Adult Sumatran Tiger (Panthera Tigris, Carnivora) Hemoglobins, Meeno Jahan, Aftab Ahmed, Gerhard Braunitzer, Reinhard Göltenboth

Pharmacy Faculty Articles and Research

The complete amino-acid sequences of the hemoglobins from the adult Sumatran tiger (Panthera tigris sumatrae) have been determined on automatic liquid- and gas-phase sequenators. The globin chains were isolated by reverse phase HPLC on a column of Nucleosil-C4.7V-Acetylserine was detected by FAB-mass spectroscopy as TV-terminal amino acid residue of the βI chain. Comparing the sequences of the globin chains of the tiger with that of human Hb-A, 23 substitutions were recognized in the a, 29 in βI and 28 in the βII chain.

Interactions Between Aquatic Chromogenic Bacteria And Pathogenic Vibrio Spp., John Louis Harris

Biological Sciences Theses & Dissertations

Interactions between populations inhabiting an ecosys­tem are responsible, in large part, for determining which species coexist in that ecosystem. In this study, interac­tions between selected Vibrio species, V. alginolyticus and V. anguillarum, and marine heterotrophic, chromogenic bac­teria in aquatic microcosms were investigated. The ultimate goal of this project was to evaluate the feasibility of ex­ ploiting competitive interactions as a means to biologically control growth of the pathogenic marine bacteria, V. alginolyticus and V. anguillarum. In the majority of ex­periments (14/16), if chromogenic species were allowed to develop stable populations before a Vibrio spp. was intro­duced into a …

An Analysis Of Protein-Ligand Interactions For Enzyme Ii-Mannitol From Escherichia Coli, Brent Lee Wood

Loma Linda University Electronic Theses, Dissertations & Projects

Enzyme II^mtl of Escherichia coli was purified from mtlA-overexpressing E. coli strain LJ1112 extraction of isolated membranes with deoxycholate, followed by hexyl agarose and ω-amino hexyl agarose chromatography in Lubrol PX. A 10-fold increase in total pure protein and 2.5-fold increase in specific activity over previously reported procedures was obtained. Tryptic fragments of Enzyme II^mtl were also purified and identified as the membrane and cytoplasmic domains by protein sequencing and SDS-PAGE. The fluorescence spectrum of Enzyme II^mtl suggested that two populations of tryptophan residues existed with emission maxima at 322 and 344 nm, corresponding to buried …

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 …

Determination Of Homology Between The Arsenic Resistance Plasmids R45 And R773 In Escherichia Coli, Joshua T. Clark

Dissertations and Theses

The resistance transfer factor R45 from Escherichia coli confers inducible arsenate and arsenite resistance in that bacterium. The genes for these resistances were cloned into the EcoR1 - Sph1 multiple cloning site of PGEM3 Blue vector (Promega) to produce a 4.9 kilobase plasmid, pJC1. This recombinant plasmid, pJC1, conferred IPTG induced resistance to arsenite and arsenate. In addition, pJCl was tested for homology with the E. coli plasmid R773, which encodes for arsenic resistance in that bacterium as well.

Through DNA-DNA hybridization the arsenic resistance determinants of R45 and R773 were compared. Under stringent hybridization conditions, R45 demonstrated DNA sequence …

Effects Of Oral Hygiene Measures On Clinical And Microbiological Parameters Of Periodontal Disease, Bruno Loos

Loma Linda University Electronic Theses, Dissertations & Projects

The effects of a 12-week period of oral hygiene alone on gingival conditions and subgingival microflora in 15 patients with severe periodontitis were investigated. In addition, subgingival microsamples were compared during this oral hygiene phase with those obtained 1 week after debridement. Clinical measurements and subgingival samples from selected sites were taken at week 0 (baseline), week 6, and week 12. Microbial samples were also taken at week 13, that is, one week following debridement. At week 0 the patients were instructed in supragingival plaque control and at week 6 the hygiene regimen was supplemented with the subgingival use of …

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 …

Short Term Temporal And Spatial Variability Of Phytoplankton In The Elizabeth River, Robert L. O'Reilly

Biological Sciences Theses & Dissertations

This study was designed to evaluate short-term temporal and spatial components of phytoplankton variability within a tidal estuarine system, in reference to natural changes in the local environment.

Multiple water samples were collected weekly from October to December 1984 at 4 stations in different branches, or sections, of the Elizabeth River. Collection of chlorophyll~ data was structured to fit an analysis of variance, while the phytoplankton species and their environmental relationships were analyzed using multivariate techniques.

Lower chlorophyll a concentrations from 0.75 to 2.87 ug/1 were characteristic of the Main Stem and Southern Branch, while higher values of 1.27 …

Long Season Wheat, W. R. Smith, K. Anderson

Experimental Summaries - Plant Research

Agronomy of long season wheats, 87AL9, 87AL10, 87ES3, 87ES4, 87JE2, 87JE3, 87MT8, 87MT9 and 87NA9. Septoria control in long season wheat, 87E4 and 87MT10. Nitrogen response by long season wheat, 87ES5 and 87JE4. Phenology of long season wheats, 87E5 and 87MT11.