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Endotoxin, Inflammation, And Intestinal Function In Livestock, Venkatesh Mani, Thomas E. Weber, Lance H. Baumgard, Nicholas K. Gabler 2012 Iowa State University

Endotoxin, Inflammation, And Intestinal Function In Livestock, Venkatesh Mani, Thomas E. Weber, Lance H. Baumgard, Nicholas K. Gabler

Animal Science Publications

Endotoxin, also referred to as lipopolysaccharide (LPS), can stimulate localized or systemic inflammation via the activation of pattern recognition receptors. Additionally, endotoxin and inflammation can regulate intestinal epithelial function by altering integrity, nutrient transport, and utilization. The gastrointestinal tract is a large reservoir of both gram-positive and gram-negative bacteria, of which the gram-negative bacteria serve as a source of endotoxin. Luminal endotoxin can enter circulation via two routes: 1) nonspecific paracellular transport through epithelial cell tight junctions, and 2) transcellular transport through lipid raft membrane domains involving receptor-mediated endocytosis. Paracellular transport of endotoxin occurs through dissociation of tight junction protein ...


Arsenic Contamination In Groundwater In Vietnam: An Overview And Analysis Of The Historical, Cultural, Economic, And Political Parameters In The Success Of Various Mitigation Options, Thuy M. Ly 2012 Pomona College

Arsenic Contamination In Groundwater In Vietnam: An Overview And Analysis Of The Historical, Cultural, Economic, And Political Parameters In The Success Of Various Mitigation Options, Thuy M. Ly

Pomona Senior Theses

Although arsenic is naturally present in the environment, 99% of human exposure to arsenic is through ingestion. Throughout history, arsenic is known as “the king of poisons”; it is mutagenic, carcinogenic, and teratogenic. Even in smaller concentrations, it accumulates in the body and takes decades before any physical symptoms of arsenic poisoning shows. According to the World Health Organization (WHO), the safe concentration of arsenic in drinking water is 10 µg/L. However, this limit is often times ignored until it is decades too late and people begin showing symptoms of having been poisoned.

This is the current situation for ...


Mutation And Complementation Of A Cellulose Synthase (Cesa) Gene, Ahmed Y. El-Araby 2012 University of Rhode Island

Mutation And Complementation Of A Cellulose Synthase (Cesa) Gene, Ahmed Y. El-Araby

Senior Honors Projects

Cellulose is a carbohydrate polymer that is composed of repeating glucose subunits. Being the most abundant organic compound in the biosphere and comprising a large percentage of all plant biomass, cellulose is extremely plentiful and has a significant role in nature. Cellulose is present in plant cell walls, in commercial products such as those made from wood or cotton, and is of interest to the biofuel industry as a potential alternative fuel source. Although indigestible by humans, cellulose is nutritionally valuable, serving as a dietary fiber. Because of its ubiquity and importance in many areas, studying cellulose will prove to ...


The Herring River Estuary: Understanding Salt Marsh Restoration And How To Predict The Response Of Phragmites Australis To Increased Tidal Flow, Theresa Murphy 2012 University of Rhode Island

The Herring River Estuary: Understanding Salt Marsh Restoration And How To Predict The Response Of Phragmites Australis To Increased Tidal Flow, Theresa Murphy

Senior Honors Projects

My presentation invites you to learn about what is involved in planning a salt marsh restoration project. The Herring River Estuary is a disturbed salt marsh ecosystem at Cape Cod National Seashore which has been diked since 1909. The National Park Service (NPS), in cooperation with many partners, is engaged in efforts to restore the now impacted 1,100 acre estuary by re-introducing tidal flow. There is significant complexity involved in trying to restore such an intricate system- from the multitude of environmental factors to important social and economic consequences. There are also several benefits to restored tidal flow. My ...


The Influence Of Anadromous Alewife On Maine Lakes And Streams: Using Nutrient Limitation Assays And Stable Isotopes To Track Marine-Derived Nutrients, Katie G. Norris 2012 The University of Maine

The Influence Of Anadromous Alewife On Maine Lakes And Streams: Using Nutrient Limitation Assays And Stable Isotopes To Track Marine-Derived Nutrients, Katie G. Norris

Electronic Theses and Dissertations

Anadromous fish can act as nutrient subsidies to freshwater ecosystems when they return there to spawn. However, relatively few studies have quantified the role of alewife (Alosa pseudoharengus) as an ecologically important source of marine-derived nutrients (MDN) to lakes and streams. Primary producers in lakes and streams are often limited by nutrients, such as nitrogen and phosphorus. If alewife bring nutrients to lakes and streams, then the limitation of primary producers in those systems should be alleviated. Nutrient limitation assays and stable isotopes were used to examine the effects of alewife MDN on Maine lakes and their outlet streams. Nutrient ...


Analyzing Big Cat Behaviors In An Artificial Environment, Krystal L. Ostrowski 2012 Olivet Nazarene University

Analyzing Big Cat Behaviors In An Artificial Environment, Krystal L. Ostrowski

Honors Program Projects

The purpose of this research is, to observe big cat behaviors at The Exotic Feline Rescue Center, and analyze these behaviors in comparison to known behaviors, to see the affects an artificial environment has on these cats. In this study the term artificial environment refers to anything outside of the natural habitat. The behaviors studied include: aggressive territory behaviors, feeding behaviors and communication behaviors. The behaviors were studied in Tigers, Lions, Cougars and Bobcats. These cats were studied during feeding, while on tours, and while doing normal walk-arounds.

The results of this study show cats in captivity do exhibit similar ...


Anonymity And Consumption: How Modern Technology And Pressure Affect The Eating Habits Of College Students, Jessica A. Laso 2012 University of Rhode Island

Anonymity And Consumption: How Modern Technology And Pressure Affect The Eating Habits Of College Students, Jessica A. Laso

Senior Honors Projects

One of the biggest issues in our society today is the increase in obesity. Despite the amount of available data on the negative health effects or possible solutions and food alternatives, the problem has not seemed to haven gotten any better. In more recent years, the notorious "freshman 15" has even become a victim to obesity and is weighing in as the "freshman 30." What is causing college students to become more susceptible to weight gain? There has been much research conducted to find the common causes of over-eating and weight gain, especially amongst those in college. After reading several ...


Possible Distorting Effects Of Gef26 In Drosophila Melanogaster, Kaylie C. Church 2012 Olivet Nazarene University

Possible Distorting Effects Of Gef26 In Drosophila Melanogaster, Kaylie C. Church

Honors Program Projects

Segregation distortion is a meiotic drive system that results in the favorable inheritance of the SD chromosome over the SD+counterpart. SD produces a malfunctioning form of RanGAP, instead of being able to move in and out of the nucleus this truncated anGAP is unable to be exported and therefore aggregates within the nucleus. This appears to affect RspS during the condensation phase of spermatogenesis, but the exact mechanism for this is unknown. In order to further understand the working components of this system, specific deletions within the second chromosome were studied. The study was conducted systematically by beginning with ...


Automation Of Tangential Flow Filtration For Purification Of Biosynthetic Spider Silk, Candace N. Clark 2012 Utah State University

Automation Of Tangential Flow Filtration For Purification Of Biosynthetic Spider Silk, Candace N. Clark

Undergraduate Honors Capstone Projects

The objective of this project is to create a user-friendly, automated flow regulation system for a tangential flow filtration (TFF) process. These filtration units are crucial for the initial stages of extracting the spider silk proteins from transgenic goat milk. Automated flow regulation systems do exist, but not at an appropriate scale for this application. This system will allow bench-top studies to be conducted with automated efficiency. Spider silk is an amazing material and if commercially available, it could be used in hundreds of applications. Currently, cost effective production is the most significant issue stopping large-scale production and use of ...


The Haptotactic Motility Of Angiogenic Endothelial Cells, Breana E. Bennett 2012 University of Maine

The Haptotactic Motility Of Angiogenic Endothelial Cells, Breana E. Bennett

Honors College

Angiogenesis, an essential but often pathological biological process, requires complex cellular coordination. This coordination is achieved through numerous extracellular signals. We investigated the role of the extracellular matrix (ECM) protein fibronectin in the support of angiogenesis and endothelial cell motility. The directed migration in response to increasing concentration of ECM proteins is termed haptotaxis. We created a preliminary, two-dimensional model of the haptotactic motility of endothelial cells using a step change in fibronectin density as a substrate. Bovine aortic endothelial cells (BAECs) exhibited directional motility towards the higher fibronectin concentration side. In addition, the physical and mechanical properties of BAECs ...


Optimization Of A Fluorescent In Situ Hybridization Protocol In The Chloroplast Hosting Mollusc Elysia Chlorotica, Geoffry Austin Davis 2012 The University of Maine

Optimization Of A Fluorescent In Situ Hybridization Protocol In The Chloroplast Hosting Mollusc Elysia Chlorotica, Geoffry Austin Davis

Honors College

The symbiosis between the mollusc Elysia chlorotica and chloroplasts of its algal prey, Vaucheria litorea, has challenged the understanding of chloroplast biology. E. chlorotica feeds on and retains the algal chloroplasts within its digestive cells. The chloroplasts remain photosynthetically active for months in the animal’s cells devoid of the algal nucleus which encodes approximately 90% of the proteins required for the chloroplasts. To help explain the ability of E. chlorotica to maintain functionally active chloroplasts, horizontal gene transfer (HGT) of V. litorea nuclear genes to the E. chlorotica genome has been hypothesized. However, the extent of HGT, as well ...


Characterization Of Genes In The Cftr-Mediated Innate Immune Response, Eric Peterman 2012 The University of Maine

Characterization Of Genes In The Cftr-Mediated Innate Immune Response, Eric Peterman

Honors College

Recently, the Kim Lab has shown that the cystic fibrosis transmembrane conductance regulator (cftr) gene is responsible for mediating resistance to Pseudomonas aeruginosa in a zebrafish infection model. Using the Gene Expression Omnibus, an NCBI functional genomics data repository, it was determined that Smad3, a transcription factor in the TGF-β signaling pathway, is upregulated in the presence of P. aeruginosa. It was found that in our zebrafish model, the Smad3 paralogs Smad3a and Smad3b are upregulated following microinjection of a cftr antisense morpholino oligomer. It was also found that microinjection of Smad3a and Smad3b morpholinos, along with a Smad2 morpholino ...


The Role Of Reactive Oxygen Species In Autophagy Activation During Candida Albicans Infection, Ashley E. Norum 2012 The University of Maine

The Role Of Reactive Oxygen Species In Autophagy Activation During Candida Albicans Infection, Ashley E. Norum

Honors College

The immune system protects us against disease through a variety of mechanisms that result in pathogen elimination. Host innate immune cells can control infections by activating NADPH oxidase, which generates reactive oxygen species (ROS) to kill pathogens directly. A defective NADPH oxidase leads to chronic granulomatous disease (CGD), which causes recurrent infections within the host. Autophagy, a cellular recycling pathway, can also target pathogens for destruction and may be a pathway that is compromised within a CGD patient. Recent work suggests that autophagy can be activated by ROS in vitro. By utilizing transparent zebrafish, we are able to characterize the ...


Environmental Factors Linked To Harmful Algal Bloom Induced Shellfish Toxicity In Cobscook Bay, Maine, Hannah M. Horecka 2012 The University of Maine

Environmental Factors Linked To Harmful Algal Bloom Induced Shellfish Toxicity In Cobscook Bay, Maine, Hannah M. Horecka

Honors College

The Gulf of Maine experiences annual closures of shellfish harvesting due to the accumulation of toxins resulting from harmful algal blooms of the dinoflagellate Alexandrium spp. If ingested by humans, these toxins can cause paralytic shellfish poisoning. The factors affecting the timing, location, and magnitude of these events remain poorly understood. Previous work found no obvious correlations between Gulf of Maine oceanographic variability and interannual variability in toxicity in the strongly tidally mixed eastern Maine coastal region in the vicinity of Cobscook Bay. Using 21 years (1985-2005) of Maine Department of Marine Resources shellfish toxicity data, interannual variability in two ...


Salinity Tolerance Of The Oyster Mudworm Polydora Websteri, Shannon W. Brown 2012 The University of Maine

Salinity Tolerance Of The Oyster Mudworm Polydora Websteri, Shannon W. Brown

Honors College

The marine worm Polydora websteri is one of many polychaete species that burrow into the shells of commercially important shellfish. In Maine, local eastern oyster (Crassostrea virginica) farmers are struggling with an infestation of this pest. The worm egests muddy wastes in its burrow causing irritation to the oyster. In response, the oyster secretes new shell material over the burrow forming mud blisters. These blisters are unsightly and decrease the market value of infested oysters, especially for oysters sold in the half-shell trade. In addition to the reduction in market value, the worm may cause physiological stress on the oyster ...


The Effects Of White Noise Disturbance On Zebra Finch Behavior; Does Disturbance Predictability Matter?, Kathryn Chenard 2012 The University of Maine

The Effects Of White Noise Disturbance On Zebra Finch Behavior; Does Disturbance Predictability Matter?, Kathryn Chenard

Honors College

It is undeniable that the progress of human civilization has altered the natural landscape of the world in ways that range from the merely aesthetic to the irreparably destructive. Some impacts are patently obvious. Others may not be as obvious to the casual observer, and yet they can be just as important in terms of truly understanding not only our impact on the world around us, but how we can mitigate this impact.

One of the most far-reaching of these latter impacts is the increased and altered levels of background noise upon the natural acoustic landscape. These changes have the ...


The Role Of Traf2 In Zebrafish, Bradie N. Manion 2012 The University of Maine

The Role Of Traf2 In Zebrafish, Bradie N. Manion

Honors College

Tumor necrosis factor (TNF) receptor associated factor 2 (Traf2) is suspected to be involved in the anti-apoptotic pathways of the innate immune system in the zebrafish. The expression of three different forms of Traf2, 2a1, 2a2, and 2b, was knocked down in pairs using antisense morpholino oligonucleotides in zebrafish embryos. A rescue was attempted by knocking down a potential receptor for the Traf2 to pathway. After infection with snakehead rhabdovirus (SHRV), mortality was quantified and the apoptotic effects of each of the Traf2 genes was assessed. Cell death was quantified using the TUNEL technique. The findings indicated that at least ...


Resistance Of Abomasal Parasites To Common Anthelmintics In Small Ruminants In The Northeast, Alexandra M. Settele 2012 The University of Maine

Resistance Of Abomasal Parasites To Common Anthelmintics In Small Ruminants In The Northeast, Alexandra M. Settele

Honors College

The abomasal worm of ruminants, Haemonchus contortus, is detrimental to Northeast sheep and goats. It is also often resistant to anthelmintics commonly used by sheep producers in Maine. We developed methods to assess response of these parasites to anthelmintics. Fecal samples from experimentally infected sheep in West Virginia and from two farms in Maine were used as sources of parasite ova and larvae in these experiments. Parasites were grown to the L3 stage, examined, and then studied using motility tests, Methylthiazol Tetrazolium (MTT) assays and spectrophotometry. Due to selection for resistance over time in Maine parasites, we expect anthelmintics to ...


Effect Of Combined Drug Therapy And Genetic Modifiers On Hepatosteatosis And Fibrosis In A Mouse Model For Alström Syndrome, Ryan Hanusek 2012 The University of Maine

Effect Of Combined Drug Therapy And Genetic Modifiers On Hepatosteatosis And Fibrosis In A Mouse Model For Alström Syndrome, Ryan Hanusek

Honors College

Alström Syndrome (ALMS) is a genetic disorder characterized by obesity, progressive hearing and vision loss, and insulin resistance in humans. Variability of additional phenotypes exists among patients, often complicating diagnosis of ALMS (Marshall et al., 2011). Postmortem studies of patients with ALMS revealed severe fibrosis in multiple organs (Marshall et al., 2011). Currently, there are no known treatments for the fibrosis observed in ALMS patients. The purpose of the studies described herein was to examine the effects of losartan, an antifibrotic drug, on fibrogenesis and to identify genomic loci that modify ALMS phenotypes in a mouse model for ALMS (Alms1Gt ...


Identification Of Internal Parasites Of Sheep And Goats, Amanda Chaney 2012 The University of Maine

Identification Of Internal Parasites Of Sheep And Goats, Amanda Chaney

Honors College

Abomasal worms are a major cause of small ruminant disease. Differentiation of the most pathogenic nematode, H. contortus, from the other common species can be difficult using standard diagnostic fecal floatation techniques because the ova are similar in size and morphology. Known pure culture H. contortus fecal samples from West Virginia University were used to develop morphologic assays using FITC-labeled lectin agglutination and immunocytochemistry to identify species of abomasal worms. These assays were applied to assess disease due to abomasal worms on selected small ruminant farms in Maine. The diagnostic tests were used to test the hypothesis that H. contortus ...


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