Research Methods in Life Sciences Commons^™

Growth And Survival Of Salamanders Exposed To Different Formulations Of Glyphosate-Based Herbicide, Jessica Johnson

Mahurin Honors College Capstone Experience/Thesis Projects

Amphibian populations have been experiencing rapid declines worldwide in the past few decades. There are many proposed causations, including the use of agricultural chemicals such as herbicides. Glyphosate based herbicides are one of the most widely used herbicides. This study looks at the effects of different brands of glyphosate-based herbicides, including those intended for aquatic use, on the survival and growth of axolotl salamander larvae. Out of four brands of glyphosate herbicide (Aquamaster, Aquaneat, Helosate plus, and Roundup Pro), the survival rates of Roundup Pro were the lowest. Most mortality occurred between the 3 mg/L and 6 mg/L concentrations, during …

Rnaseq Analysis Of The Drosophila Response To The Entomopathogenic Nematode Steinernema., Shruti Yadav, Sean Daugherty, Amol Carl Shetty, Ioannis Eleftherianos

Computational Biology Institute

Drosophila melanogaster is an outstanding model to study the molecular and functional basis of host-pathogen interactions. Currently, our knowledge of microbial infections in D. melanogaster is well understood; however, the response of flies to nematode infections is still in its infancy. Here, we have used the potent parasitic nematode Steinernema carpocapsae, which lives in mutualism with its endosymbiotic bacteria Xenorhabdus nematophila, to examine the transcriptomic basis of the interaction between D. melanogaster and entomopathogenic nematodes. We have employed next-generation RNA sequencing (RNAseq) to investigate the transcriptomic profile of D. melanogaster larvae in response to infection by S. carpocapsae symbiotic (carrying …

Effects Of Phosphodiesterase 3a Modulation On Murine Cerebral Microhemorrhages, Rachita K. Sumbria, Vitaly Vasilevko, Mher Mahoney Grigoryan, Annlia Paganini-Hill, Ronald Kim, David H. Cribbs, Mark J. Fisher

Pharmacy Faculty Articles and Research

Background: Cerebral microbleeds (CMB) are MRI-demonstrable cerebral microhemorrhages (CMH) which commonly coexist with ischemic stroke. This creates a challenging therapeutic milieu, and a strategy that simultaneously protects the vessel wall and provides anti-thrombotic activity is an attractive potential approach. Phosphodiesterase 3A (PDE3A) inhibition is known to provide cerebral vessel wall protection combined with anti-thrombotic effects. As an initial step in the development of a therapy that simultaneously treats CMB and ischemic stroke, we hypothesized that inhibition of the PDE3A pathway is protective against CMH development.

Methods: The effect of PDE3A pathway inhibition was studied in the inflammation-induced and …

Linking Large Scale Ocean-Atmospheric Patterns With Recruitment In Kellet’S Whelk (Kelletia Kelletii), Katherine N. Rodriguez

Biological Sciences

Global warming influences the biogeography of many marine and terrestrial species. Understanding species range shifts is ecologically and socioeconomically important when guiding management decisions for ecosystems exposed to a rapidly changing climate. In this natural experiment, I follow Danielle Zacherl’s methods (Zacherl et al. 2003) to study the effects of large-scale ocean-atmospheric patterns on recruitment of a marine snail, Kellet’s whelk (Kelletia kelletii); these organisms recently expanded their range North past the geographic barrier of Point Conception to Monterey, CA, USA. I use shell length data collected at 32 subtidal rocky reef kelp forest sites in 2015 (before …

Effects Of Food Consumption On Cell Proliferation In The Brain Of Python Regius, Stacy Star Habroun

Master's Theses

Neurogenesis is an important and vastly under-explored area in reptiles. While the ability to generate new brain cells in the adult mammalian brain is limited, reptiles are able to regenerate large populations of neuronal cells. Pythons exhibit a characteristic specific dynamic action (SDA) response after food intake with an increase in metabolic rate that facilitates processing the meal. Associated with this change in SDA, pythons (Python spp.) also exhibit impressive plasticity in their digestive and cardiovascular physiology due to the sheer magnitude of the increase in organ growth that occurs after a meal to speed digestion, absorption, and assimilation of …

The Effect Of Resource Quality And Species Interactions On The Colonization Behavior Of The Black Blow Fly, Phormia Regina (Meigen), Melissa N. Branker

Student Theses

During decomposition, there are many different insects groups that utilize carrion as a resource. In particular, blow flies (Order: Diptera; Family: Calliphoridae) are considered to be a forensically important family due to their ability to rapidly locate and colonize a carrion resource. As a result, blow flies are commonly used as indicator species in PMI estimations. However, recent research indicates that the colonization behavior of these species can be influenced by a variety of abiotic and biotic factors. In this study, the effects of arrival order, resource quality and bacterial or species cues on the oviposition behavior of Phormia regina …

Investigation Into The Mechanism Of Ion Transport In Rio Negro Characiformes, Vineza D. Reduta

Undergraduate Honors Theses

Four fish species within the Characiform Order [(Rosy tetras (Hyphessobrycon rosaceus), Serpae tetras (Hyphessobrycon eques), Emperor tetras (Nematobrycon palmeri) and Penguin tetras (Thayeria obliqua)] are native to the ion-poor, acidic waters of the Rio Negro. In this paper, we focus on Wood’s revised Na⁺/NH₄⁺ exchange model to gain better insight into the mechanisms of ion transport within the Characids. We exposed each species to two experimental treatments: (i) 1mM ammonia (high external ammonia [HEA]), to test coupling of Na⁺ uptake and ammonia excretion, and (ii) 100μM Acetazolamide …

Estimation Of The True Evolutionary Distance Under The Fragile Breakage Model., Nikita Alexeev, Max A Alekseyev

Computational Biology Institute

BACKGROUND: The ability to estimate the evolutionary distance between extant genomes plays a crucial role in many phylogenomic studies. Often such estimation is based on the parsimony assumption, implying that the distance between two genomes can be estimated as the rearrangement distance equal the minimal number of genome rearrangements required to transform one genome into the other. However, in reality the parsimony assumption may not always hold, emphasizing the need for estimation that does not rely on the rearrangement distance. The distance that accounts for the actual (rather than minimal) number of rearrangements between two genomes is often referred to …

Mitigating The Conflict Between Pitfall-Trap Sampling And Conservation Of Terrestrial Subterranean Communities In Caves, Peter Kozel, Tanja Pipan, Nina Šajna, Slavko Polak, Tone Novak

International Journal of Speleology

Subterranean habitats are known for their rich endemic fauna and high vulnerability to disturbance. Many methods and techniques are used to sample the biodiversity of terrestrial invertebrate fauna in caves, among which pitfall trapping remains one of the most frequently used and effective ones. However, this method has turned out to be harmful to subterranean communities if applied inappropriately. Traditionally, pitfall traps have been placed in caves solely on the ground. Here we present an optimized technique of pitfall trapping to achieve a balance between sampling completeness and minimal disturbance of the fauna in the cave. Monthly we placed traps …

Tumor Necrosis Factor Α Inhibition For Alzheimer's Disease, Rudy Chang, Kei-Lwun Yee, Rachita K. Sumbria

Pharmacy Faculty Articles and Research

Tumor necrosis factor α (TNF-α) plays a central role in the pathophysiology of Alzheimer’s disease (AD). Food and Drug Administration–approved biologic TNF-α inhibitors are thus a potential treatment for AD, but they do not cross the blood-brain barrier. In this short review, we discuss the involvement of TNF-α in AD, challenges associated with the development of existing biologic TNF-α inhibitors for AD, and potential therapeutic strategies for targeting TNF-α for AD therapy.

Responsible Translation Of Stem Cell Research: An Assessment Of Clinical Trial Registration And Publications, Moses Fung, Yan Yuan, Harold Atkins, Qian Shi, Tania M. Bubela

Office of the Provost

We assessed the extent to which the publication of clinical trial results of innovative cell-based interventions reflects International Society for Stem Cell Research best practice guidelines. We assessed: (1) characteristics and time to publication of completed trials; (2) quality of reported trials; and (3) results of published trials. We identified and analyzed publications from 1,052 novel stem cell clinical trials: 179 (45.4%) of 393 completed trials had published results; 48 trials were registered by known stem cell tourism clinics, none of which reported results. Completed non-industry-sponsored trials initially published more rapidly, but differences with industry-sponsored trials decreased over time. Most …

Development Of Neurotensin-Based Radiopharmaceuticals For Neurotensin-Receptor-1-Positive Tumors Targeting, Yinnong Jia

Theses & Dissertations

The neurotensin receptor 1 (NTR1) is overexpressed in many cancers, due to its role as a growth pathway. These NTR1-positive cancers include pancreatic, colon, prostate and breast cancers. In the radiopharmaceutical field, the overexpression of NTR1 in cancer has prompted the development of NTR1-targeted diagnostics and therapeutics. The neurotensin (NT) peptide exhibits low nanomolar affinity for NTR1 and has been the paradigm for NTR1-targeted agents. Since the 1980’s, radiolabeled NT analogs have been developed and evaluated for targeting NTR1-positive cancers. Since native NT is rapidly degraded in vivo by a variety of peptidases, a tremendous amount of effort has been …

California Horn Snail Exhibit A Bimodal Size Distribution And Size-Associated Dispersal Patterns, Isai L. Lopez

Honors Thesis

The California Horn Snail (Cerithideopsis californica) is an important primary intermediate host in the life cycle of a variety of parasitic species that have extensive effects on ecological food webs. As such, parasite load in the California Horn Snail can serve as an important tool in assessing the effectiveness of restoration projects. The goal of the study was to investigate the population dynamics of the California Horn Snail in Ballona Wetlands, California, the only major coastal salt marsh in Los Angeles County. This study evaluated the spatial dispersion, size distribution, and density of C. californica collected from the …

Does Genotype Correlate With Phenotype? Evaluating Ruffed Lemur (Varecia Spp.) Color Vision Using Subject Mediated Automatic Remote Testing Apparatus (Smarta), Raymond Vagell

Theses and Dissertations

Ruffed lemur (Varecia spp.) color vision research was conducted using a multidisciplinary approach: psychophysics, genetic analysis, technology, and animal training. The behavioral manifestation of Varecia spp. trichromacy was shown using a touchscreen apparatus (SMARTA). Trichromats performed better than dichromats when discriminating red from green (G₂ = 78.10, p < 0.001).

The Effect Of Ambient Temperature On Recovery Of Surgical Stress In Sprague-Dawley Rats, Romie D. Powell

Masters Theses, 2010-2019

Laboratory animals are housed at ambient temperatures ranging from 20°C – 26°C per recommended guidelines. Rats in particular typically prefer ambient temperatures (Tamb) of ~27°C (Brown et al, 2011). When rats undergo surgical instrumentation for experimental use, they often recover at normal room temperature (~21°C). While this is comfortable to those maintaining them, it may lead to a cold thermal stress for the rats. It is hypothesized that housing rats at ambient temperatures away from their preferred Tamb could lead to a thermal stress, which adversely affects surgical recovery. To address this, rats (220g-350g) were surgically instrumented with a radiotelemetry …

Functional Analysis And Treatment Of Self-Injurious Feather Plucking In A Black Vulture (Coragyps Atratus), Kristen L. Morris

Thesis Projects

Feather plucking (FP) is a maladaptive behavior observed in captive avian species. This self-injurious behavior results in damage to and removal of feathers and skin tissue, resulting in animal welfare and financial consequences. The etiology and maintenance of FP have been hypothesized through medical and environmental processes, yet a definitive solution has not been found. The current study investigated the environmental variables maintaining the FP of a Black Vulture (Coragyps atratus), as well as evaluated a function-based treatment for this behavior. The behavior was found to be maintained by positive reinforcement in the form of contingent attention. Treatment …

Transcriptomic Effects Of Dispersed Oil In A Non-Model Decapod Crustacean, Hernan Vazquez-Miranda, Brent Thoma, Juliet Wong, Darryl Felder, Keith A. Crandall, Heather Bracken-Grissom

Computational Biology Institute

Background. Oil spills are major environmental disasters. Dispersants help control spills, as they emulsify oil into droplets to speed bioremediation. Although dispersant toxicity is controversial, the genetic consequences and damages of dispersed oil exposure are poorly understood. We used RNA-seq to measure gene expression of flatback mudcrabs (Eurypanopeus depressus, Decapoda, Brachyura, Panopeidae) exposed to dispersed oil.

Methods. Our experimental design included two control types, oil-only, and oil-dispersant treatments with three replicates each. We prepared 100 base pair-ended libraries from total RNA and sequenced them in one Illumina HiSeq2000 lane. We assembled a reference transcriptome with all replicates per treatment, …

Lymphoid Hematopoiesis And The Role Of B-Cells In Transgenic Mouse Model Of Sickle Cell Disease, Christina Cotte

University Scholar Projects

Sickle cell disease (SCD) has been shown to be associated with decreased baseline immunity and thus increased susceptibility to infection. I sought to discern possible causes of this by looking into the correlations between SCD and hematopoiesis, the immune system and the neuroendocrine system, and ultimately by conducting experiments surrounding the impaired immune system of SCD. These experiments focused on the potential causes and effects of the diminution of B-1a cells in the SCD spleen. Adoptive transfers, infections with Streptococcus pneumoniae, and histologic imaging were conducted to establish if the diminution of the B-1a cells in the SCD spleen …

The Use Of Probiotics To Control The Microbial Load Present In Commercial Broiler Chicken Hatch Cabinets As An Alternative To Formaldehyde Fumigation, Lucas Elzie Graham

Graduate Theses and Dissertations

Formaldehyde has been used for decades as a disinfectant in the poultry hatchery. Hatch cabinets are treated with formaldehyde to control the microbial bloom that occurs inside of the hatch cabinet as the hatch progresses. Even with formaldehyde being a known human carcinogen and the detriment that it has on living creatures millions of chicks are exposed to formaldehyde in the hatch cabinet. In these experiments we tested a lyophilized probiotic spray inside of the hatch cabinets from day nineteen to day twenty one to control the microbial bloom that occurs. Hatch cabinet environments were sampled in six experiments. Media …

In Ovo Evaluation Of Floramax-B11 On Marek's Disease Hvt Vaccine Protective Efficacy, Hatchability, Microbiota Composition, Morphometric Analysis, And Salmonella Enteritidis Infection In Broiler Chickens, Kyle Dean Teague

Graduate Theses and Dissertations

It has previously been shown that effective probiotics can accelerate gut maturation and the development of a normal microflora in poultry. This results in increased resistance to enteric pathogens encountered by chicks early in life. Our objective in experiments 1 and 2 was to evaluate the effect of in ovo administration of FloraMax®-B11 (FM) on Marek’s disease (MD) herpesvirus of turkeys (HVT) vaccine protective efficacy. In Exp. 1, day 18 White Leghorn embryos were randomly distributed in four groups, 1) HVT vaccinated, no MDV challenge, 2) HVT + FM vaccinated, no MDV challenge, 3) HVT vaccinated, challenge with virulent MDV, …