Skip to main content Skip to navigation
Showcase Marilyn Reed

Herbicide Detection with Nanoparticle-Amplified Immunoassays

Herbicide Detection with Nanoparticle-Amplified Immunoassays

Primary author: Eunice Kwon
Faculty sponsor: Bernard Van Wie

Primary college/unit: Voiland College of Engineering and Architecture
Campus: Pullman

Abstract:

New detection methods are being developed to monitor potentially harmful pesticides and herbicides, which are suspected of contributing to ailments ranging from diarrhea to death. In this study, we present the detection of the herbicide atrazine—approximately 65 million pounds of which are used in the United States per year—with two types of immunoassay while using a novel mesoporous palladium@platinum (Pd@Pt) core-shell nanoparticle (NP) detection label. Pd@Pt NPs have peroxidase-like catalytic activity, reducing hydrogen peroxide while oxidizing the substrate, resulting in higher pH- and thermo-stability than enzymes and greater catalytic activity than monometallic Pt black. We replaced the enzyme in the indirect ELISA method with Pd@Pt NPs, forming a nanoparticle-linked immunosorbent assay (NLISA) that eliminated a step in the detection process. We used this competitive NLISA on atrazine, yielding a limit of detection of 0.5 ppb (10% inhibition) with 0.1 – 500 ppb linear range, then on water samples spiked with atrazine at three concentrations, yielding 98 – 115 % recoveries. We then used LFIA with a Pd@Pt NP detection label on atrazine; in this case, test line intensity increased with decreasing atrazine concentration, because competitive immunoassays yield inverse results. Finally, we evaluated our methods by comparing our results with those obtained with the instrumental assay HPLC, which yielded an atrazine limit of detection of 10 ppb. We found that our novel Pd@Pt NP detection label has a higher sensitivity than HPLC and that NLISA saves time and reagents by eliminating the secondary antibody step.

Tropomyosin binding is essential for tropomodulin to regulate spine reorganization

Tropomyosin binding is essential for tropomodulin to regulate spine reorganization

Primary author: Balaganesh Kuruba
Faculty sponsor: Alla Kostyukova

Primary college/unit: Voiland College of Engineering and Architecture
Campus: Pullman

Abstract:

Formation of connections between neurons (synapses) is essential for proper brain function. Synapses are formed by axon terminals and dendrites (spines and shafts). Spine formation and reorganization depend on actin polymerization and depolymerization. Disruption in this process affects spine formation and thereby impairs many brain cognitive functions. Tropomodulin is a protein which controls polymerization of actin by binding to actin via tropomyosin, another actin binding protein. In our study, we showed that disruption of tropomyosin-binding ability of tropomodulin 2 resulted in changes in spine morphology, overall reduction of spine density and average spine length in primary hippocampal neurons. Tropomodulin interacts with two tropomyosin molecules during regulation of actin polymerization. No atomic structural information is available for the binding interface between tropomodulin and tropomyosin. Establishing the structure is critical to understand the actin dynamics regulation mechanism by tropomodulin. Using circular dichroism and nuclear magnetic resonance spectroscopic studies, we showed that tropomyosin peptide containing first 44 N-terminal residues is the optimal fragment to form respective stable complexes with the two tropomyosin-binding sites in tropomodulin.

Moving to Better Health Care? Evidence from the Impact of Medicaid Expansion on Homeless Individuals in the U.S.

Moving to Better Health Care? Evidence from the Impact of Medicaid Expansion on Homeless Individuals in the U.S.

Primary author: Ashutosh Kumar
Faculty sponsor: Ben Cowan

Primary college/unit: Agricultural, Human and Natural Resource Sciences
Campus: Pullman

Abstract:

Homeless individuals grapple with varied health problems but have limited access to health care. This study extends the literature on health care and homelessness and provides the first causal evidence of the impact of the Medicaid expansion on migration of homeless individuals from non-expansion to expansion states. The Medicaid expansion, adopted by 26 states and Washington DC and rejected by 24 states in January 2014, expanded coverage to previously uninsured homeless individuals. Besides health care, the expansion equipped homeless service providers with extra flexibility to tackle homelessness through several supportive services and housing-related activities, absent in non-expansion states. Using the state level data, released by the Department of Housing and Urban Development (HUD), on the homeless population from 2009-2018, estimates from a difference-in-differences model suggest migration of homeless individuals, where expansion states saw statistically significant 4.4 percent increase, while non-expansion states simultaneously experienced a 22.6 percent decline. Furthermore, utilizing the difference in coverage status of homeless individuals vis-a-vis homeless people in families (who had pre-expansion coverage), estimates from a triple difference (DDD) model also confirm a significant migration. Previous studies documenting the positive impact of Medicaid expansion on a number of outcomes – improved coverage and health care utilization, reduced financial hardships and medical bills sent to collection, and increased household savings – compliment the results of this study. This paper provides additional evidences that Medicaid expansion had no significant impact on the number of homeless veterans or on indicators like bankruptcy, unemployment rate and poverty rate.

Evaluating the impact of pharmacist-led HIV and HCV screening and education on adults experiencing homelessness in Spokane, Washington

Evaluating the impact of pharmacist-led HIV and HCV screening and education on adults experiencing homelessness in Spokane, Washington

Primary author: Sorosh Kherghehpoush
Co-author(s): Kimberly McKeirnan

Primary college/unit: College of Pharmacy and Pharmaceutical Sciences
Campus: Spokane

Abstract:

Over half a million people experience homelessness on a given night in the United States. As a result of increased exposure to disease, violence, unsanitary conditions, stress, malnutrition and substance abuse, homeless persons experience medical problems and treatment complications at higher rates than the general population.

Chronic disease states that require uninterrupted treatment and high rates of adherence, such as Hepatitis C and HIV/AIDS, are more difficult to control in those with unstable housing. Individuals living with HIV/HCV who are unaware of their infection are more likely to transmit these diseases than persons who are aware of their HIV/HCV diagnosis. Gay and bisexual men account for the majority of new HIV diagnoses followed by injection drug users who account for the majority of Hepatitis C infection, two sub-populations that are also disproportionately affected by homelessness.

Given the barriers to clinical engagement and the persistent stigma, HIV and HepC provide an important opportunity for pharmacist involvement.

In this research study, participants will undergo an HIV and HCV point-of-care screening test complimented with comprehensive HIV and HCV education and personalized risk mitigation strategies. Study participants who have a reactive screening are referred to a partnering HIV/HCV specialist to establish care and the local health district for anonymous partner notification.

There are wide-ranging implications associated with this study. Early recognition and treatment to reduce transmission. Increased access to care even for the uninsured. Lower healthcare costs associated with emergency room visits. improved health literacy of a vulnerable population.

The Use of Ecological Momentary Assessment Protocols in Neuropsychology: A Meta-Analysis

The Use of Ecological Momentary Assessment Protocols in Neuropsychology: A Meta-Analysis

Primary author: Olasunkanmi Kehinde
Co-author(s): Maureen Schmitter-Edgecombe
Faculty sponsor: Prof. Maureen Schmitter-Edgecombe

Primary college/unit: College of Education
Campus: Pullman

Abstract:

The aim of this meta-analysis is to examine the use of Ecological Momentary Assessment (EMA) protocols in different kinds of neuropsychological disorders to uncover the different factors that could moderate the effectiveness of EMA protocols in neuropsychology. Studies with the use of EMA to collect neuropsychological and psychological disorder data in the last 10 years were considered. A meta-analysis of 16 studies was performed to investigate the design characteristics of EMA protocols and possible factors that could moderate the effective use of EMA protocols in measuring any form of disorder in neuropsychology. Overall, the use of EMA protocols in measuring the neuropsychological and psychological disorder across studies were found to be effective (g =0.32). The distribution was heterogeneous Q (15) = 492.48, p < .05, I^2 = 96.95. A total of 97% of the variance that is due to true heterogeneity was between-studies variance while 3% of the variance was within-study variance based on sampling error. The studies with incentives, daily random prompts, duration of EMA, and the length of EMA might positively promote the quality of data collected from participants who are diagnosed with a neurological or psychological disorder. This meta-analysis has implications for the ways psychological disorders are measured momentarily.

Keywords: Protocol; Neuropsychology; Ecological Momentary Assessment

De-escalation of antibiotic therapy in acute exacerbation of COPD (AECOPD)

De-escalation of antibiotic therapy in acute exacerbation of COPD (AECOPD)

Primary author: Anne Keef
Faculty sponsor: Dr. Megan Undeberg

Primary college/unit: College of Pharmacy and Pharmaceutical Sciences
Campus: Spokane

Abstract:

COPD patients are at increased risk of pulmonary infections secondary to their underlying pathology of the disease: compromised lung function coupled with increased inflammation and mucus production within the lungs provides for a breeding ground for infection. COPD patients are at increased risk of infection by M. catarrhalis, H. influenzae, and S. pneumoniae. Typically, these pathogens induce upper respiratory tract infections. In the COPD patient, however, the compromised lung function and decline in innate respiratory elevator clearing functions results in an increased risk for bacteria to invade the lower respiratory tract and induce inflammation and infection. Additionally, infection with Pseudomonas is not uncommon in COPD patients with more severe symptoms at baseline and especially those with recurrent infections. Regardless of the pathogenic cause, the resultant increase in inflammation in the lungs places the COPD patient at increased risk for further decompensation and increased morbidity. As a result, when a patient presents with cardinal symptoms of an infection inducing an acute exacerbation of COPD (AECOPD), it is not uncommon for a patient to be started on empiric, broad spectrum antibiotic therapy with Pseudomonas coverage, pending sputum culture results. However, once sputum cultures have resulted, antimicrobial therapy is not always refined to correlate with the pathogen present. Our project proposes looking at AECOPD admissions for the first quarter of 2019, initial antibiotic choice, sputum culture results, and subsequent change or no change to antibiotic therapy. Results from this information will guide antimicrobial stewardship and provider education.

Pricing Strategies in the Presence of Interventions

Pricing Strategies in the Presence of Interventions

Primary author: Sadegh Kazemi
Faculty sponsor: Stergios B. Fotopoulos

Primary college/unit: Carson College of Business
Campus: Pullman

Abstract:

Motivated by real-life pricing practices, we consider a pricing problem under uncertain conditions where the customer’s willingness-to-pay (WtP) changes at an unknown point over the selling horizon. An important feature of our model is that the seller only observes the sales outcomes and has limited knowledge of the underlying WtP distribution before and after the intervention. Given the uncertainty associated with the seller’s estimate of the time of change, we obtain the probability distribution of the seller’s maximum likelihood estimate (MLE) of the intervention time. Furthermore, we characterize the seller’s expected revenue loss due to the under- or overestimation of the intervention time and propose an easily implementable procedure to approximate the seller’s revenue under-performance. Our study reveals two important findings. First, the seller tends to underestimate the intervention time in the face of negative events that lower the customer’s reservation price. Conversely, the seller is prone to overestimation when the intervention inflates the customer’s reservation price. Second, we show that the seller’s revenue under-performance is minimal both when the shift in WtP distribution parameter(s) is either very small or considerably large. While our analytical results significantly contribute to the revenue management literature on their own, we also provide an accurate numerical method to easily obtain and interpret the results in a meaningful way for managerial use.

Gene expression varies with disease and parasitism in the green sea turtle (Chelonia mydas) skin transcriptome

Gene expression varies with disease and parasitism in the green sea turtle (Chelonia mydas) skin transcriptome

Primary author: Rachael Kane
Faculty sponsor: Andrew Storfer

Primary college/unit: Arts and Sciences
Campus: Pullman

Abstract:

Emerging infectious diseases (EIDs) are a major threat to biodiversity in the 21st Century. Fibropapillomatosis (FP) has been classified as an EID and it plagues both juvenile and adult marine turtles. FP is an epithelial tumor disease that affects marine turtles globally. While FP tumor gene expression has been characterized, no transcriptomics studies have been performed on healthy Chelonia mydas individuals or tissues. Here, we perform RNA-Seq on healthy skin tissue of juvenile C. mydas individuals with FP and without FP from the Indian River Lagoon, Florida, USA. We assembled a de novo C. mydas transcriptome to identify significantly differentially expressed genes (DEGs) based on turtle presence of FP tumors and leech parasitism. Significantly DEGs were found in all expression analyses and included candidate genes that may play a role in C. mydas recovery from FP. Although tumor inhibition genes were found to be expressed in both FP-negative and positive individuals, positive individuals had twice as many upregulated significantly differentially expressed genes, indicating a possible response to FP affliction. A general trend of downregulated intra- and inter- cell signaling genes was observed in the leech infected individuals. A Gene Ontology enrichment analysis showed few enriched biological processes. Interestingly, FP-negative individuals showed enrichment of T cell cytokine production. Clearly, C. mydas respond to disease and parasitism by regulating their transcription, and transcriptomics provides a promising venue to further explore this crippling disease.

Modeling and Miniaturization of a Centrifugal Bioreactor with Applications in Cancer Immunotherapy and Chemical Engineering Education

Modeling and Miniaturization of a Centrifugal Bioreactor with Applications in Cancer Immunotherapy and Chemical Engineering Education

Primary author: Kitana Kaiphanliam
Co-author(s): Brenden Fraser-Hevlin, Bernard Van Wie
Faculty sponsor: Bernard J. Van Wie

Primary college/unit: Voiland College of Engineering and Architecture
Campus: Pullman

Abstract:

A centrifugal bioreactor (CBR) system has been designed and studied in Professor Bernard Van Wie’s laboratory with applications ranging from tissue engineering for arthritis to T cell biomanufacturing for cancer therapies. A major issue in using the CBR for T cell expansion is the numerous sources for potential contamination, as half of the system is exposed outside of a biosafety cabinet. If the current system were implemented in hospitals, it would require a cleanroom costing up to $3 million; however, if the CBR was downsized to fit in a biosafety cabinet, containment costs would be reduced to $15,000, at most. By reducing the size of the CBR to fit in a biosafety cabinet and assuming proper aseptic technique is followed, we will nearly eliminate contamination sources, making the system more affordable and accessible for cancer immunotherapy applications. Current efforts in the downsizing process include drafting and modeling of a prototype scalable to that of a compact disc (CD). Additionally, the CBR can be further miniaturized as a hands-on learning module for classroom use. The physics principles that define the CBR can be used to introduce separations to chemical engineering undergraduate students, as well as expose them to applications in the biomedical field. We hypothesize that these CBR-like fidget spinner modules will increase motivation and retention amongst female students in a freshman-level chemical engineering course. Prototypes for the hands-on learning modules have been manufactured, and we will be implementing them along with motivational assessments in the spring CHE 110 class.

When is a threat more or less of a threat? The sensitivity of highly central identities to threat and the increased likelihood of feeling offended, identity protection, withdrawal, and antisocial behaviors

When is a threat more or less of a threat? The sensitivity of highly central identities to threat and the increased likelihood of feeling offended, identity protection, withdrawal, and antisocial behaviors

Primary author: Hana Johnson
Co-author(s): JT Bates

Primary college/unit: Carson College of Business
Campus: Pullman

Abstract:

High identity centrality refers to identities (i.e., self-definitions) that are so important to individuals that they are top-of-mind for them across situations. These identities are highly salient and may therefore easily transition from being top-of-mind to actually affecting behavior; this can occur when identities are under threat. In the workplace, identity threat may result directly from insulting comments or criticisms but may also arise more inadvertently through work practices or changes in management. If these types of experiences involve a highly central identity, we argue that employees are more likely to perceive a threat. We then further explore how employees respond to threat to highly central identities by identifying the different emotional and behavioral responses individuals engage when the target of the threat is a more versus less central identity.

We test the sensitivity of highly central identities to threat in an experimental pilot study and then explore responses to threat related to highly central identities in a qualitative study. Using a grounded theory approach, we find that individuals are more likely to feel offended and engage in behaviors to protect their identities when threat is related to highly central identities. This protection of identities requires sustained effort to minimize the identity threat. In addition, when individuals experience threat to highly central identities, they are more likely to withdraw from situations and behave in an antisocial manner such as engaging in angry and aggressive behavior. Our work has implications for theory on identity, identity threat, and negative emotions.