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Distribution Of Ground-Layer Plant Species In A Fragmented Landscape In The Corozal District, Belize, Central America, Divan Catzim Jan 2007

Distribution Of Ground-Layer Plant Species In A Fragmented Landscape In The Corozal District, Belize, Central America, Divan Catzim

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In this study, I specifically looked at three major issues regarding 36 target plant species in a fragmented landscape in the Corozal district, Belize: 1) Determine woodlot characteristics that tend to favor the target species. 2) Determine plant characteristics that tend to favor the target species. 3) Determine whether age and size of a woodlot favors the presence of the target species. The study area was divided into three areas and each area had woodlots varying in sizes and ages. 36 plant species were sampled in all woodlots upon which woodlot characteristics and species characteristics were associated with the number …


Tree Seedling Establishment Under The Native Shrub, Asimina Triloba, Marilyn Cabrini Baumer Jan 2007

Tree Seedling Establishment Under The Native Shrub, Asimina Triloba, Marilyn Cabrini Baumer

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Species that form forest understory layers affect canopy tree seedling establishment worldwide. In the Eastern United States, shrub understories like Rhododendrom maximum, a native evergreen species, and Lonicera maackii, an exotic, invasive species, diminish tree seedling survival. I compared the density and survival of canopy tree seedlings under and outside patches of the native shrub, Asimina triloba (L.) Dunal (Annonaceae) (pawpaw). I also conducted a manipulative experiment to determine whether above ground or below ground competition was more important in seedling growth and survival. Above ground competition was manipulated by tying back the leaves of the pawpaw and below ground …


Modulation Of The 3'Igh Regulatory Region (3'Igh Rr), A Prospective In Vitro Screening Tool For Identifying Potential Immunotoxicants, Rebecca Anne Henseler Jan 2007

Modulation Of The 3'Igh Regulatory Region (3'Igh Rr), A Prospective In Vitro Screening Tool For Identifying Potential Immunotoxicants, Rebecca Anne Henseler

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The immune system is critical to human survival. However, assessing alterations of immune function by potential immunotoxicants is complicated by the diffuse nature of the immune system, which is composed of various effector cells each with differing effector functions. Current immunotoxicity testing is limited to animal studies. We have developed a model, which may provide an in vitro alternative to animal studies in identifying immunotoxicants that specifically target B cell function (i.e., alteration of immunoglobulin (Ig) or expression and antibody secretion). This model consists of a well-characterized B cell line, CH12.LX, which appears to appropriately model primary B cell function. …


Neurodegeneration And Neuroinflammation In A Mouse Model Of Sarin Exposure, Molly Elizabeth Davidson Jan 2007

Neurodegeneration And Neuroinflammation In A Mouse Model Of Sarin Exposure, Molly Elizabeth Davidson

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Sarin is an organophosphorus (OP) ester chemical warfare agent (CWA) that has been used in past terrorist attacks. It remains a threat today because of its ease of manufacture and dispersal. Sarin acts by irreversibly inactivating acetylcholinesterase and interfering with neurotransmission by allowing acetylcholine to build up at neuro-effector junctions, where it continuously elicits a response. Symptoms of sarin toxicity include seizures, hypersecretions, respiratory distress and death in extreme cases. Previous studies on OP poisoning indicate that sarin exposure causes neurodegeneration and neuroinflammation in conjunction with seizure activity. In order to determine the mode of neuronal death and the extent …


Molecular Identification Of Chironomid Species Based On Its-1 And Its-2 Regions Of Rdna, Monita Sharma Jan 2007

Molecular Identification Of Chironomid Species Based On Its-1 And Its-2 Regions Of Rdna, Monita Sharma

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Of all major aquatic invertebrate groups, members of family Chironomidae are most abundant and show a wide range of habitat preferences. The importance of correct identification of Chironomids has been realized in many bioassessment studies mainly because of their worldwide distribution, substrate specificities and predictable responses to various pollutants in the water sources. This study establishes that the sequence data from the Intergenic Spacer Regions (ITS) of ribosomal DNA could be used as molecular markers to distinguish between different Chironomidae species and also to identify them. The need to use molecular approaches, to identify various Chironomidae species, comes from the …


Acute Toxicity And Immunotoxicity Testing Of Total Petroleum Hydrocarbons In Aquatic And Terrestrial Organisms, Andrea Renee Handy Jan 2007

Acute Toxicity And Immunotoxicity Testing Of Total Petroleum Hydrocarbons In Aquatic And Terrestrial Organisms, Andrea Renee Handy

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The acute toxicity and immunotoxicity of JP-8 jet fuel on Chironomus tentans, Hyallela azteca, Lactuca sativa, Eisenia foetida, and Lumbricus terrestris was assessed using standard USEPA acute toxicity and static renewal toxicity tests. Three methods of spiking test soil with jet fuel were evaluated. In one method acetone was utilized as a carrier and the soil was dried in the fume hood; in another the soil was spiked directly with jet fuel and also was dried; and in the last the soil was spiked directly without drying. There was low survival in C. tentans in all treatments, including controls. There …


Angiotensin At1 Receptor Blockade Protects The Brain From Ischemic Damage, Madhuri Penchikala Jan 2007

Angiotensin At1 Receptor Blockade Protects The Brain From Ischemic Damage, Madhuri Penchikala

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Angiotensin (Ang) AT1 receptors are considered to play an important role in ischemic stroke via degenerative processes leading to cell death. Recent clinical and basic studies show that systemic blockade of Ang AT1 receptors reduces brain lesion in ischemic stroke. In this study we evaluated whether blockade of central Ang AT1 receptors protects the brain from ischemia and inflammation during ischemic stroke. Adult male C57BL/6 mice were divided into two groups for chronic intracerebroventricular (ICV) infusion of a selective Ang AT1 receptor antagonist, losartan (Los, n=18, 2 ug/hr) or isotonic saline (Con, n=20) using osmotic minipump. Twelve days post infusion, …


Investigation Of Interactions Between Rev And Microtubules: Purification Of Wild-Type And Mutant Rev Protein And Optimization Of Microtubule Depolymerization Assays, Miller, Kelly Robbins Jan 2007

Investigation Of Interactions Between Rev And Microtubules: Purification Of Wild-Type And Mutant Rev Protein And Optimization Of Microtubule Depolymerization Assays, Miller, Kelly Robbins

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As a logical pharmaceutical target for antiviral drugs, HIV-1 Rev is a regulatory protein essential for viral infection (Hope, 1999). The development of antiviral drugs that target Rev has been hindered by the lack of high-resolution structural information due to the protein's tendency to aggregate in solution. While searching for solution conditions rendering Rev amenable to crystallographic analyses, Watts et al., (2000) discovered a novel in vitro interaction between Rev and microtubules (MTs) whereby addition of equimolar Rev and tubulin forms bilayered rings called Rev-tubulin toroidal complexes (RTTs). RTTs are similar to those seen when MTs are mixed with certain …


Analysis Of Sex Reversal And Tra-2 Nucleotide Variation In Tropical And Temperate Clades Of Caenorhabditis Briggsae, Irene Zelepuhin Jan 2007

Analysis Of Sex Reversal And Tra-2 Nucleotide Variation In Tropical And Temperate Clades Of Caenorhabditis Briggsae, Irene Zelepuhin

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Reproductive isolation results when members of the same species cannot reproduce due to either prezygotic or postzygotic mechanisms, therefore restricting gene flow between populations. A leading model describing reproductive isolation developed by J.B. Haldane (1922) states, "When offspring from two different animal species have one sex that is rare, absent, or sterile, that sex is the heterozygous (XO) or heterogametic (XY) sex". Haldane's rule is illustrated among various animal taxa regardless of which sex is heterogametic. To date, Caenorhabditis mating tests are the only example of Haldane's rule that is caused by sexual transformation and not gender specific lethality or …


Characteristics Of A Foamy Virus-Derived Vector That Allow For Safe Autologous Gene Therapy To Correct Leukocyte Adhesion Deficiency Type 1, Ryan Matthew Mcnichol Jan 2007

Characteristics Of A Foamy Virus-Derived Vector That Allow For Safe Autologous Gene Therapy To Correct Leukocyte Adhesion Deficiency Type 1, Ryan Matthew Mcnichol

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The hematopoeitic stem cell is a prime target for gene therapy in the attempt to correct a number of single gene inherited genetic defects that affect the immune system. In persons affected by leukocyte adhesion deficiency type 1 (LAD-1) the gene for the Beta-2 subunit of the integrin molecule is mutated. This autosomal recessive gene defect yields a phenotype with little or no beta-2 integrin expression on leukocytes. Beta-2 integrin expression is essential for leukocytes to travel from the blood to the tissues to fight infection. Persons with this disease have lowered leukocyte counts in the tissues and as a …


Immunological And Developmental Effects Of Polybrominated Diphenyl Ethers (Pbdes) And 2,3,7,8-Tetrachloro-P-Dioxin (Tcdd) In Birds, Randy T. Stetzer Jan 2007

Immunological And Developmental Effects Of Polybrominated Diphenyl Ethers (Pbdes) And 2,3,7,8-Tetrachloro-P-Dioxin (Tcdd) In Birds, Randy T. Stetzer

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This thesis contains two separate and distinct research projects with a common overall theme - the study of immunotoxicity associated with the developmental exposure of young birds to halogenated chemicals posing environmental concern. These chemicals share many chemical characteristics, including environmental ubiquity and longevity, one has been studied extensively since the 1970s, and one is a relatively new environmental contaminant with few studies pertaining to toxicological affects on humans or wildlife. Specific summaries of each study begin each project chapter. The first study was entitled Developmental and Immunological Effects of a Commercial Mixture of PBDE Flame Retardants in Chicken Embryos. …


Hsv-1 Infection Of C3h Central Nervous System Cell Lines, Lauren Kay Van Buren Jan 2007

Hsv-1 Infection Of C3h Central Nervous System Cell Lines, Lauren Kay Van Buren

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Herpes Simplex Virus Type 1 (HSV-1) can infect the nervous system, resulting in a disease known as herpes encephalitis (HSE). Herpes encephalitis affects thousands of people each year; many cases are fatal or permanently debilitating. Approximately two thousand known cases occur in the United States each year alone (Neuroland online source). Acyclovir has been the drug of choice used to treat herpes encephalitis. Even after the administration of acyclovir, permanent neurological damage and/or death often results. Thousands of individuals would benefit by the discovery of drugs that are more effective at preventing lasting HSE damage and death. Knowledge concerning HSE …


Hypoxic Induction And The Role Of Hifs In The Activation Of Luciferase Constitutive Reporters In Placental Stem Cells, Diane Michelle Doran Jan 2007

Hypoxic Induction And The Role Of Hifs In The Activation Of Luciferase Constitutive Reporters In Placental Stem Cells, Diane Michelle Doran

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Hypoxia is critically important to the development of the embryo and placenta. Proper placental development is critical for normal fetal growth and embryonic survival. Abnormal placental development has been implicated in numerous obstetric complications, including preeclampsia, which affects about 7% of all pregnancies and can be fatal for both mother and baby. Rodent and murine trophoblast stem cells differentiate into three distinct cell lineages: giant cells, spongiotrophoblasts, and labyrinthine cells, which form different layers and have different functions within the placenta. Recent studies in our laboratory have focused on the invasive giant cell layer using the rodent Rcho-1 choriocarcinoma stem …


Detection And Destruction Of Escherichia Coli Bacteria And Bacteriophage Using Biofunctionalized Nanoshells, Joseph E. Van Buren Jan 2007

Detection And Destruction Of Escherichia Coli Bacteria And Bacteriophage Using Biofunctionalized Nanoshells, Joseph E. Van Buren

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The ability to detect chemical and biological agents is arguably one of the highest priority technical challenges today. The capability to obtain specific information at and near single-molecule resolution is the ultimate goal in chemical and biological agent detection. Metallic nanostructures, nanoshells and nanorods in particular, are attractive substrates because of their plasmonic properties. Combining the specificity of biomolecular recognition with these nanostructures might lead to increased sensitivity and selectivity. Localization of biological recognition motifs to the surface of these nanostructures could provide a mechanism for highly specific and directed energy transfer when bound to its target. This study utilizes …


Due-B In Chromatin And Nuclear Speckles, Nadia Katrangi Jan 2007

Due-B In Chromatin And Nuclear Speckles, Nadia Katrangi

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The DNA unwinding element binding protein (DUE-B) was first identified by using a yeast one hybrid screen with the DNA unwinding element (DUE) from the c-myc origin as bait. DUE-B's orthologue in the yeast Saccharomyces cerevisiae lacks the last 60 C-terminal amino acids and has been identified as a D-tyrosyl-tRNA deacylase. A substantial group of evidence suggests a role for DUE-B in the regulation of replication initiation. Here we show that DUE-B is focused in nuclear speckles and colocalizes with spliceosome associated protein 145 (SAP145), an mRNA splicing factor 3B subunit. Mass spectrometry results show that SAP145 co-purifies with the …


Role Of Angiotensin Converting Enzymes Ace And Ace2 In Diabetes Induced Cardiovascular Dysfunction, Keerthy Kanakamedala Jan 2007

Role Of Angiotensin Converting Enzymes Ace And Ace2 In Diabetes Induced Cardiovascular Dysfunction, Keerthy Kanakamedala

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Cardiovascular disease is a long term complication of diabetes, which remains a leading cause of mortality and morbidity. There is recent evidence for activation of the Renin angiotensin system (RAS) in diabetic animals and humans. Emerging evidence shows that the vasoconstrictor actions of Ang II may be opposed by formation of the vasodilator, Ang (1-7). There is limited data on blood pressure in murine models of type 2 diabetes. The aim is to study the role of angiotensin converting enzymes ACE and ACE2 in diabetes induced cardiovascular dysfunction using type 2 diabetic murine mouse models (db/db mice). Both db/db mice …


Oral Ld50 Of Botulinum Toxin Serotype A In Guinea Pigs, Christina Marie Wilhelm Jan 2007

Oral Ld50 Of Botulinum Toxin Serotype A In Guinea Pigs, Christina Marie Wilhelm

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As a disease, botulism is a neuroparalytic illness resulting from the action of a potent neurotoxin produced by C. Botulinum. Of the seven distinct C. Botulinum neurotoxin serotypes: A, B, C, D, E, F, and G, only serotypes A, B, E and F cause human disease. The duration of action of the seven toxin serotypes varies with serotype A having the most sustained action (i.e. months vs. days in serotype E). This study was performed due to recently identified critical gaps in our food safety procedures. The goal of this study was to assess whether fresh 2% milk provided protective …


The Processing Of Β-Endorphin In Morphine Treated Rats Using Seldi-Tof Mass Spectrometry, Jennifer Y. Edwards Jan 2007

The Processing Of Β-Endorphin In Morphine Treated Rats Using Seldi-Tof Mass Spectrometry, Jennifer Y. Edwards

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Endocrine glands secrete peptide hormones that bind to specific receptors, and elicit a response. In the pituitary, prohormone convertases (PC) PC1/3 and PC2 convert inactive prohormones into biologically active peptide hormones. Proopiomelanocortin (POMC) is a precursor molecule that proteolytically cleaves at paired basic residue sites, and produces smaller biologically active peptides, such as adrenocorticotropic hormone (ACTH), α-melanocyte stimulating hormone (α-MSH), and β-endorphin. β-endorphin is an endogenous opioid peptide hormone that plays a vital role in the body's physiological response to stress, fear, and anxiety. Morphine is an exogenous opioid, used for the treatment of moderate to severe pain and competes …


Discovery Of New Antimicrobial Agents Using Combinatorial Chemistry, William I. Northern Jan 2007

Discovery Of New Antimicrobial Agents Using Combinatorial Chemistry, William I. Northern

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Combinatorial chemistry has become an important aspect of medicinal research due to its flexibility and the ability to produce large numbers of potential therapeutic agents. Once compounds are made, they must be screened to determine if there is any biological activity. This research project focused on developing a screening method for chemical agents produced by a graduate student in the chemistry department at Wright State University. After an acceptable screening method was found, the goal of the project was to determine if compounds produced had either antibacterial activity, antifungal activity, or both. Seven compounds exhibited biological activity. Two of these …


Differential Effects Of Mutant Tap63Γ On Transactivation Of P53 And/Or P63 Responsive Genes And Their Effects On Global Gene Expression, Shama Khan Khokhar Jan 2007

Differential Effects Of Mutant Tap63Γ On Transactivation Of P53 And/Or P63 Responsive Genes And Their Effects On Global Gene Expression, Shama Khan Khokhar

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p63, a member of the p53 gene family, known to play a role in development, has more recently also been implicated in cancer progression. Mice lacking p63 exhibit severe developmental defects such as limb truncations, abnormal skin, and absence of hair follicles, teeth, and mammary glands. Germline missense mutations of p63 have been shown to be responsible for several human developmental syndromes including SHFM, EEC and ADULT syndromes and are associated with anomalies in the development of organs of epithelial origin. The contrasting phenotypes associated with the different classes of p63 mutations might be in part due to the differential …


Vglut And Gad65 Expression In Physiologically Characterized Ia Afferents, Ivonne Nkoli Ukpabi Jan 2007

Vglut And Gad65 Expression In Physiologically Characterized Ia Afferents, Ivonne Nkoli Ukpabi

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Peripheral nerve injury is known to induce several changes in the physiology and morphology of the injured afferent. These changes include hyperexcitability, decreased dorsal root potentials (DRP), loss of synaptic vesicles as well as loss of the vesicular glutamate transporter, VGLUT1. While many of the changes caused by peripheral injury revert with regeneration, others appear to be permanent. The loss of the stretch reflex for example is a puzzling outcome of recovery after peripheral nerve transection and regeneration, especially given that the electrical counterpart of the stretch reflex (the H-reflex) recovers after regeneration. We hypothesized that stretch induced transmission is …