Organisms Commons^™

The Locomotor Kinematics Of Asian And African Elephants: Changes With Speed And Size, John R. Hutchinson, Delf Schwerda, Daniel J. Famini, Robert H.I. Dale, Martin S. Fischer, Rodger Kram

Scholarship and Professional Work - LAS

For centuries, elephant locomotion has been a contentious and confusing challenge for locomotion scientists to understand, not only because of technical difficulties but also because elephant locomotion is in some ways atypical of more familiar quadrupedal gaits. We analyzed the locomotor kinematics of over 2400 strides from 14 African and 48 Asian elephant individuals (body mass 116-4632 kg) freely moving over ground at a 17-fold range of speeds, from slow walking at 0.40 m s^-1 to the fastest reliably recorded speed for elephants, 6.8 m s^-1. These data reveal that African and Asian elephants have some subtle …

In Vitro Antimicrobial Efficacy Of Calcium Hydroxides In Root Dentin, Josef W. Lubisich

Loma Linda University Electronic Theses, Dissertations & Projects

Enterococcus faecalis is the most commonly isolated bacteria in failed root canal treatment. Endodontic intracanal medicaments are commonly tested using standardized bovine cylinders infected with bacteria. The literature is not clear on whether calcium hydroxides are able to remove E. faecalis from the dentinal tubules. One reason for this is that there are several varying forms of calcium hydroxide commonly used. The purpose of the present experiment was to determine whether four commonly used calcium hydroxide products were able to reduce E. faecalis from four incremental samples of dentin and to determine if there was a statistically significant difference between …

Comparing The Use Of A Manual And A Power Toothbrush By 3-To-4 Year-Old Children, Lorena Delgado Salcedo

Loma Linda University Electronic Theses, Dissertations & Projects

PURPOSE: To compare the ability of three-to four-year-old children in performing toothbrushing with manual versus battery-powered toothbrushes with and without oral hygiene instructions.

METHODS: This study was a randomized, controlled, examiner-blind, 4-period crossover design performed on 50 healthy children, ages 3 to 4 years old. Children were assigned either a manual or power toothbrush at visit one and alternated between the two types of toothbrushes each week, for four weeks. Plaque was scored before and after brushing using the Greene and Vermillion -Simplified Oral Hygiene Index. ^18,19 At their last two visits of the study, the children received brushing instructions …

Isolation Of A Ubiquitous Obligate Thermoacidophilic Archaeon From Deep-Sea Hydrothermal Vents, Anna-Louise Reysenbach, Yitai Liu, Amy B. Banta, Terry J. Beveridge, Julie D. Kirshtein, Stefan Schouten, Margaret K. Tivey, Karen L. Von Damm, Mary A. Voytek

Biology Faculty Publications and Presentations

Deep-sea hydrothermal vents are important in global biogeochemical cycles, providing biological oases at the sea floor that are supported by the thermal and chemical flux from the Earth's interior. As hot, acidic and reduced hydrothermal fluids mix with cold, alkaline and oxygenated sea water, minerals precipitate to form porous sulphide–sulphate deposits. These structures provide microhabitats for a diversity of prokaryotes that exploit the geochemical and physical gradients in this dynamic ecosystem. It has been proposed that fluid pH in the actively venting sulphide structures is generally low (pH < 4.5), yet no extreme thermoacidophile has been isolated from vent deposits. Culture-independent surveys based on ribosomal RNA genes from deep-sea hydrothermal deposits have identified a widespread euryarchaeotal lineage, DHVE2 (deep-sea hydrothermal vent euryarchaeotic 2) Despite the ubiquity and apparent deep-sea endemism of DHVE2, cultivation of this group has been unsuccessful and thus its metabolism remains a mystery. Here we report the isolation and cultivation of a member of the DHVE2 group, which is an obligate thermoacidophilic sulphur- or iron-reducing heterotroph capable of growing from pH 3.3 to 5.8 and between 55 and 75 °C. In addition, we demonstrate that this isolate constitutes up to 15% of the archaeal population, providing evidence that thermoacidophiles may be key players in the sulphur and iron cycling at deep-sea vents.

Ewe And Wether Trials - Tools For Benchmarking Your Sheep Genetics, Lock Butler

Bulletins 4000 -

Research and sheep productivity trial results demonstrate a huge variability in genetic productivity between flocks. For example a range of up to 2 kg clean fleece weight, 5 microns, 55 percentage points in lambing percentage and 20 kg live weight, can lead to big differences in gross margin between flocks.

There is an opportunity for genetic improvement, depending on your current ram source or sires performance. For example, Western Australian (WA) Wether Trial results suggest half the WA flocks could improve clean fleece weight per head by half a kilogram or more. The trial results suggest that this could occur …

Chlorella Virus Mt325 Encodes Water And Potassium Channels That Interact Synergistically, Sabrina Gazzarrini, Ming Kang, Svetlana Epimashko, James L. Van Etten, Jack Dainty, Gerhard Thiel, Anna Moroni

James Van Etten Publications

Fast and selective transport of water through cell membranes is facilitated by water channels. Water channels belonging to the major intrinsic proteins (MIPs) family have been found in all three domains of life, Archaea, Bacteria, and Eukarya. Here we show that Chlorella virus MT325 has a water channel gene, aqpv1, that forms a functional aquaglyceroporin in oocytes. aqpv1 is transcribed during infection together with MT325 kcv, a gene encoding a previously undescribed type of viral potassium channel. Coexpression of AQPV1 and MT325-Kcv in Xenopus oocytes synergistically increases water transport, suggesting a possible concerted action of the two channels in …

Chlorella Viruses, Takashi Yamada, Hideki Onimatsu, James L. Van Etten

James Van Etten Publications

Chlorella viruses or chloroviruses are large, icosahedral, plaque‐forming, double‐stranded‐DNA— containing viruses that replicate in certain strains of the unicellular green alga Chlorella. DNA sequence analysis of the 330‐kbp genome of Paramecium bursaria chlorella virus 1 (PBCV‐1), the prototype of this virus family (Phycodnaviridae), predict ∼366 protein‐encoding genes and 11 tRNA genes. The predicted gene products of ∼50% of these genes resemble proteins of known function, including many that are completely unexpected for a virus. In addition, the chlorella viruses have several features and encode many gene products that distinguish them from most viruses. These products include: (1) multiple …

Antibiotic Resistant And Coliform Bacteria In The Ohio River; 2002 To 2004, Lisa Marie Smith

Theses, Dissertations and Capstones

During 2002 and 2003 samples, collected every five miles along the Ohio River, were analyzed for total cultivable bacteria, ciprofloxacin resistant bacteria, erythromycin resistant bacteria, tetracycline resistant bacteria, and fecal coliforms. During 2004 samples were analyzed for total cultivable bacteria, ciprofloxacin resistant bacteria, sulfamethizole resistant bacteria, tetracycline resistant bacteria, Virginiamycin resistant bacteria, total coliforms, and Escherichia coli. The objectives of this study were to systematically collect data on fecal coliforms, E. coli, and antibiotic resistant bacteria in the Ohio River and its major tributaries; to determine if antibiotic resistance populations are correlated to each other or to coliforms; and …

Stromal Haze, Myofibroblasts, And Surface Irregularity After Prk, Marcelo V. Netto, Rajiv R. Mohan, Sunilima Sinha, Ajay Sharma, William Dupps, Steven E. Wilson

Pharmacy Faculty Articles and Research

The aim of this study was to investigate the relationship between the level of stromal surface irregularity after photorefractive keratectomy (PRK) and myofibroblast generation along with the development of corneal haze.

Variable levels of stromal surface irregularity were generated in rabbit corneas by positioning a fine mesh screen in the path of excimer laser during ablation for a variable percentage of the terminal pulses of the treatment for myopia that does not otherwise generate significant opacity. Ninety-six rabbits were divided into eight groups[.]

Slit lamp analysis and haze grading were performed in all groups. Rabbits were sacrificed at 4 hr …

2,6-Hexadecadiynoic Acid And 2,6-Nonadecadiynoic Acid - Novel Synthesized Acetylenic Fatty Acids As Potent Antifungal Agents, Nestor Carballeira, David Sanabria, Clarisa Cruz, Keykavous Parang, Baojie Wan, Scott Franzblau

Pharmacy Faculty Articles and Research

The hitherto unknown 2,6-hexadecadiynoic acid, 2,6-nonadecadiynoic acid, and 2,9-hexadecadiynoic acid were synthesized in two steps and in 11–18% overall yields starting from either 1,5-hexadiyne or 1,8-nonadiyne. Among all the compounds 2,6-hexadecadiynoic acid displayed the best overall antifungal activity against both the fluconazole resistant Candida albicans strains ATCC 14053 and ATCC 60193 (MIC = 11 μM) and against Cryptococcus neoformans ATCC 66031 (MIC < 5.7 μM). The 2,9-hexadecadiynoic acid did not display any significant cytotoxicity against the fluconazole resistant C. albicans strains, but it showed fungitoxicity against C. neoformans ATCC 66031 with a MIC value of <5.8 μM. Other fatty acids, such as 2-hexadecynoic acid, 5-hexadecynoic acid, 9-hexadecynoic acid, and 6-nonadecynoic acid were also synthesized and their antifungal activities compared. The 2-hexadecynoic acid, a known antifungal fatty acid, exhibited the best antifungal activity (MIC = 9.4 μM) against the fluconazole resistant C. albicans ATCC 14053 strain, but it showed a MIC value of only 100 μM against C. albicans ATCC 60193. The fatty acids 2,6-hexadecadiynoic acid and 2-hexadecynoic acid also displayed a MIC of 140–145 μM towards Mycobacterium tuberculosis H37Rv in Middlebrook 7H12 medium. In conclusion, 2,6-hexadecadiynoic acid exhibited the best fungitoxicity profile compared to other analogues. This diynoic fatty acid has the potential to be further evaluated for use in topical antifungal formulations.

Rapid Determination Of Reduced And Oxidized Glutathione Levels Using A New Thiol-Masking Reagent And The Enzymatic Recycling Method: Application To The Rat Liver And Bile Samples, Imam H. Shaik, Reza Mehvar

Pharmacy Faculty Articles and Research

A microtiter plate assay for quantitation of reduced (GSH) and oxidized (GSSG) glutathione in the rat liver tissue and bile is described. The assay is based on the established enzymatic recycling method and a new thiol-masking reagent, 1-methyl-4-vinyl-pyridinium trifluoromethane sulfonate (M4VP). Samples were first processed by homogenization with (liver) or addition of (bile) sulfosalicylic acid. The total glutathione and GSSG were then determined before and after rapid (>= 2 min) and efficient (100%) masking of the GSH content of the samples with M4VP followed by the enzymatic recycling assay. The percentages of error and coefficient of variation of the …

Effect Of Prophylactic And Therapeutic Mitomycin C On Corneal Apoptosis, Cellular Proliferation, Haze, And Long-Term Keratocyte Density In Rabbits, Marcelo V. Netto, Rajiv R. Mohan, Sunilima Sinha, Ajay Sharma, Pankaj C. Gupta, Steven E. Wilson

Pharmacy Faculty Articles and Research

PURPOSE—To determine the mechanism through which topical mitomycin C prevents and treats corneal haze after photorefractive keratectomy (PRK) and to examine the effects of dosage and duration of exposure.

METHODS—In 224 New Zealand rabbits, −9.0 diopter PRK with mitomycin C or balanced salt solution was performed. Haze level was graded at the slit-lamp. Rabbits were sacrificed at 4 hours, 24 hours, 4 weeks, or 6 months after surgery and immunohistochemistry was performed with TUNEL assay, Ki67 and α-SMA.

RESULTS—TUNEL-positive apoptotic cells marginally increased in all mitomycin C groups whereas Ki67-positive mitotic cells decreased significantly following mitomycin C application. A greater …

Attenuation Of Acute Rejection In A Rat Liver Transplantation Model By A Liver-Targeted Dextran Prodrug Of Methylprednisolone, Anjaneya Chimalakonda, Donald L. Montgomery, Jon A. Weidanz, Imam H. Shaik, Justin H. Nguyen, John J. Lemasters, Eiji Kobayashi, Reza Mehvar

Pharmacy Faculty Articles and Research

Background. The use of methylprednisolone (MP) and other corticosteroids for the treatment of acute liver allograft rejection is associated with severe toxicities in nontarget tissues. Therefore, selective delivery of NIP to the liver may improve its efficacy and alleviate its side effects. We investigated the effects of a novel liver-targeted dextran prodrug of MP (DMP) in an orthotopic rat liver transplantation (OLT) model.

Methods. The model consisted of a high responder rejection strain combination (Dark Agouti donors and Lewis recipients). Liver recipients were intravenously administered saline or a single subtherapeutic dose of MP (5 mg/kg) as the parent …

Natural And Synthetic Viniferins Associated With The Grapevine Disease Young Vine Decline, David Michael Mcginnis

Chemistry & Biochemistry Theses & Dissertations

Grapevine disease has been thc subject of intense research amongst viticulturists over the last few decades, especially during the 1990's. There has been discoveries that suggest grapevine disease is commonly caused by fungal pathogens. One of the most common fungi that the vine may become infected by is known as Botrytis cinerea. B. cinerea is capable of attacking the grapevine which in turn will lead to bunch rot in the grape clusters. This disease has been researched in great detail during the past several years and is one of only few microorganisms that have actually been identified. Phaeoacremrmium chnlmydospnrum …

The Structure Of A T=169d Algal Virus, Pbcv-1, At 15Å Resolution, X. Yan, V. Bowman, N. H. Olson, James Gurnon, James L. Van Etten, Michael G. Rossmann, T. S. Baker

James Van Etten Publications

Paramecium bursaria chlorella virus 1 (PBCV-1) (genus Chlorovirus, family Phycodnaviridae), infects certain unicellular, exsymbiotic, chlorella-like green algae [1]. The PBCV-1 virion (~1x109 Da) has a linear dsDNA genome (330kbp) and contains at least 100 different proteins [1, unpublished data]. A published cryo-electron microscopy and three-dimensional (3D) image reconstruction of PBCV-1 (26Å resolution) revealed that the outer icosahedral glycoprotein capsid, with a maximum diameter of 1,900Å along the five-fold axis, consists of 1680 trimeric capsomers (trimer) and 12 pentameric capsomers (pentamer) [2]. These capsomers are arranged on a T=169d (h=7, k=8) quasi-equivalent lattice. The trimers and pentamers are organized into 20 …

Functional Implication Of The Trna Genes Encoded In The Chlorella Virus Pbcv-L Genome, Da Young Lee, Michael V. Graves, James L. Van Etten, Tae-Jin Choi

James Van Etten Publications

The prototype Chlorella virus PBCV-l encodes 11 tRNA genes and over 350 protein-encoding genes in its 330 kbp genome. Initial attempts to overexpress the recombinant A189/192R protein, a putative virus attachment protein, in E. coli strain BL21(DE3) SI were unsuccessful, and multiple protein bands were detected on Western blots. However, the full-length A189/192R recombinant protein or fragments derived from it were detected when they were expressed in E. coli BL21 CodonPlus (DE3) RIL, which contains extra tRNAs. Codon usage analysis of the a1891192r gene showed highly biased usage of the AGA and AUA codons compared to genes encoded by E. …

Inhibition Modifies The Effects Of Slow Calcium-Activated Potassium Channels On Epileptiform Activity In A Neuronal Network Model, Keun-Hang Susan Yang, Piotr J. Franaszczuk, Gregory K. Bergey

Mathematics, Physics, and Computer Science Faculty Articles and Research

Generation of epileptiform activity typically results from a change in the balance between network excitation and inhibition. Experimental evidence indicates that alterations of either synaptic activity or intrinsic membrane properties can produce increased network excitation. The slow Ca2+-activated K+ currents (sI AHP) are important modulators of neuronal firing rate and excitability and have important established and potential roles in epileptogenesis. While the effects of changes in sI AHP on individual neuronal excitability are readily studied and well established, the effects of such changes on network behavior are less well known. The experiments here utilize a defined small network model of …

Levels Of Intravenous Enterococcus Faecalis That Cause Heart Colonization, Louis Zane Stromberg

Loma Linda University Electronic Theses, Dissertations & Projects

While previous studies have shown that presence of bacteria in systemic circulation can cause infective endocarditis, there is no information on the specific amount of bacteria necessary to cause this condition. The purpose of this study was to establish the minimum level of circulating bacteria that will cause colonization of damaged heart valves in rats. Fifty-two Sprague-Dawley rats were anesthetized and their heart valves were damaged using an established protocol. A clinical isolate of Enterococcus faecalis was transformed with a plasmid bearing the luxF and Chloramphenicol cassettes to label the bacteria with the light-emitting protein. After four weeks, the rats …

Biochemical Enrichment And Biophysical Characterization Of A Taste Receptor For L-Arginine From The Catfish, Ictalurus Puntatus., William Grosvenor, Yuri Kaulin, Andrew I Spielman, Douglas L Bayley, D Lynn Kalinoski, John H Teeter, Joseph G Brand

Department of Pathology, Anatomy, and Cell Biology Faculty Papers

BACKGROUND: The channel catfish, Ictalurus punctatus, is invested with a high density of cutaneous taste receptors, particularly on the barbel appendages. Many of these receptors are sensitive to selected amino acids, one of these being a receptor for L-arginine (L-Arg). Previous neurophysiological and biophysical studies suggested that this taste receptor is coupled directly to a cation channel and behaves as a ligand-gated ion channel receptor (LGICR). Earlier studies demonstrated that two lectins, Ricinus communis agglutinin I (RCA-I) and Phaseolus vulgaris Erythroagglutinin (PHA-E), inhibited the binding of L-Arg to its presumed receptor sites, and that PHA-E inhibited the L-Arg-stimulated ion conductance …

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 …

Hepatic Disposition Of Cyclosporine A In Isolated Perfused Rat Livers, Reza Mehvar, Anjaneya Chimalakonda

Pharmacy Faculty Articles and Research

PURPOSE. To develop an isolated perfused rat liver model to study the hepatic disposition of cyclosporine A (CyA) in both sexes.

METHODS. Livers were isolated from male (n = 6) and female (n = 7) rats and perfused with a physiological buffer in a single-pass manner. A bolus 1-mg dose of CyA was injected into the inlet catheter and periodical samples (0-15 min) were collected from the outlet perfusate. The concentrations of CyA in the outlet perfusate, collected bile (0-15 min), and liver tissue (at the end of perfusion) were quantitated by HPLC and subjected to statistical moment analysis. …

Glycosyltransferases Encoded By Viruses, Nicolas Markine-Goriaynoff, Laurent Gillet, James L. Van Etten, Haralambos Korres, Naresh Verma, Alain Vanderplasschen

James Van Etten Publications

Studies of cellular biology in recent decades have highlighted the crucial roles of glycans in numerous important biological processes, raising the concept of glycomics that is now considered as important as genomics, transcriptomics and proteomics. For millions of years, viruses have been co-evolving with their hosts. Consequently, during this co-evolution process, viruses have acquired mechanisms to mimic, hijack or sabotage host processes that favour their replication, including mechanisms to modify the glycome. The importance of the glycome in the regulation of host–virus interactions has recently led to a new concept called ‘glycovirology’. One fascinating aspect of glycovirology is the study …

Phytoplankton Composition Within The Tidal Freshwater-Oligohaline Regions Of The Rappahannock And Pamunkey Rivers In Virginia, Harold G. Marshall, Lubomira Burchardt

Biological Sciences Faculty Publications

The Rappahannock River is a major river system across north central Virginia prior to entering the Chesapeake Bay. In contrast, the Pamunkey River is smaller in size and joins the Mattoponi River to form the York River, which flows parallel to the Rappahannock before it also flows into Chesapeake Bay. A unique mixing area for both flora and environmental conditions exists in the tidal freshwater-oligohaline region of both rivers. This is a dynamic mixing section where freshwater and estuarine species are subject to the interaction of river flow and daily tidal rhythms. The phytoplankton composition in this region of the …

Characterization Of Spy1600 A Putative Hyaluronidase Gene In Group A Streptococci, Karin M. Berling

Biological Sciences Theses & Dissertations

Group A Streptococci (GAS), also known as Streptococcus pyogenes, can cause a variety of human diseases ranging from asymptomatic to life threatening. Exactly how a single type of organism is able to inflict such a multitude of diseases remains to be fully understood. One possibility includes the large number of secreted virulence factors expressed by the organism. The recent sequencing of three streptococcal genomes has indicated the existence of several previously unknown genes, some of which may encode possible virulence factors. Among these is Spy1600, which based on its sequence similarities has been proposed to encode a hyaluronidase, a …

Tomographic Reconstruction Of Treponemal Cytoplasmic Filaments Reveals Novel Bridging And Anchoring Components, Jacques Izard, Bruce F. Mcewen, Rita M. Barnard, Thomas Portuese, William A. Samsonoff, Ronald J. Limberger

Department of Food Science and Technology: Faculty Publications

An understanding of the involvement of bacterial cytoplasmic filaments in cell division requires the elucidation of the structural organization of those filamentous structures. Treponemal cytoplasmic filaments are composed of one protein, CfpA, and have been demonstrated to be involved in cell division. In this study, we used electron tomography to show that the filaments are part of a complex with a novel molecular organization that includes at least two distinct features decorating the filaments. One set of components appears to anchor the filaments to the cytoplasmic membrane. The other set of components appears to bridge the cytoplasmic filaments on the …

Ultrasonic Removal Of Bacteria From Plated Cells, Cecilia Chi-Pei Kao

Loma Linda University Electronic Theses, Dissertations & Projects

Children often present with dental trauma to pediatric emergency departments and pediatric dental offices. There is a wide spectrum of types of dental trauma. Although research has been done concerning the treatment of avulsed teeth, the current recommendations in the published guidelines might still be improved for better long term prognoses. One may speculate that ultrasonification of an avulsed tooth prior to replantation may dislodge existing surface bacteria and improve the prognosis for the tooth. This was as an in vitro study to test this concept. Epithelial cells were grown in 6-well tissue culture plates. Standardized amounts of Staphylococcus aureus …

Prevalence And Risk Factors For Vaginal Candida Colonization In Women With Type 1 And Type 2 Diabetes, Ella M. De Leon, Scott J. Jacober, Jack D. Sobel, Betsy Foxman

Wayne State University Associated BioMed Central Scholarship

Abstract

Background

Diabetes mellitus increases the rate of vaginal colonization and infection with Candida species

Methods

We surveyed women with diabetes receiving care at either an urban or suburban diabetes clinic to examine the relationship between vaginal Candida colonization, diabetes type and duration, and HbA_1c level. 101 participants completed the self-administered questionnaire and self-collected a vaginal swab for Candida culture. Candida colonization was similar by age and race.

Results

Type 1 diabetics were three times as likely as type 2 diabetics to be colonized with any Candida species (OR = 3.4; 95% CI: 1.03, 11.41; p = 0.04); even …

Dextran-Methylprednisolone Succinate As A Prodrug Of Methylprednisolone: Plasma And Tissue Disposition, Xiaoping Zhang, Reza Mehvar

Pharmacy Faculty Articles and Research

Plasma and tissue disposition of a macromolecular prodrug of methylprednisolone (MP), dextran (70 kDa)–methylprednisolone succinate (DMP), was studied in rats. Single 5‐mg/kg doses of DMP or unconjugated MP were administered into the tail veins of different groups of rats (n  = 4/group/time point). Blood (cardiac puncture) and tissues (liver, spleen, kidney, heart, lung, thymus, and brain) were collected at various times after DMP (0–96 h) or MP (0–2 h) injections. Concentrations of DMP and MP in samples were analyzed by size‐exclusion chromatography (SEC) and reversed‐phase high‐performance liquid chromatography (HPLC), respectively. Conjugation of MP with 70‐kDa dextran resulted in 22‐, …

Development Of An Electrotransformation Technique For Streptococcus Iniae And Preliminary Characterization Of The Hemolysin Associated With This Bacterium, Kimberly Ann Hahn

Biological Sciences Theses & Dissertations

Streptococcus iniae is a gram-positive organism responsible for causing disease in both freshwater as well as saltwater fish. Every year fisheries lose fish by the tons due to diseases caused by this organism. In 1991, the first reported human case of disease associated with this organism was described. Since this initial case, there have been numerous other reported cases of S. iniae infections. This organism is a catalase negative, facultatively anaerobic organism that produces a capsule and when plated onto blood agar demonstrates β-hemolytic activity.

In this study, the relationship between the hemolysin produced by S. iniae and the lactate …

Investigations Into The Innate Resistance Of The Tick, Dermacentor Variabilis, When Challenged With The Bacterium, Escherichia Coli, Shane Michael Ceraul

Biological Sciences Theses & Dissertations

In addition to the soluble response, many invertebrates control bacterial infections by means of phagocytosis or melanotic encapsulation. In some insects, Escherichia coli growth is reported to be inhibited by aggregation/encapsulation. Soluble and phagocytic responses to bacterial challenge have been reported in ticks, but evidence of an aggregation/encapsulation response was reported only for inanimate (araldite) implants. This study was done to determine how ticks control infection by E. coli. Ticks were challenged by direct inoculation of bacteria into the hemocoel cavity. Using plate counts, no viable E. coli were detected I hour post-inoculation. A direct fluorescence assay (DF A) …