Medicine and Health Sciences Commons^™

Biochemical Assay Optimization And Computational Screening Efforts To Identify Potential Luxs Inhibitors, Keeshia Q. Wang

Master's Theses

Quorum sensing (QS) is a process of coordination of bacterial gene expression in response to cell population. System two QS is regulated by the small signaling molecule autoinducer-2 (AI-2) and is implicated in the infectious behaviors of various bacterial species. AI-2 is biosynthesized from S-ribosylhomocysteine (SRH) by the enzyme LuxS and induces interspecies cell-to-cell communication. Inhibition of LuxS would therefore inhibit interspecies QS. Herein, a search for novel molecular species that will competitively bind with SRH in the LuxS binding site is performed in silico. Computational screening results are then validated in vitro using an optimized LuxS inhibition …

The Development Of A New Dry Powder Inhaler, Xi Zhang

Electronic Thesis and Dissertation Repository

A new dry powder inhaler (DPI) for respiratory drug delivery was developed. This novel device is characterized by a micro-dose, passive delivery and multiple doses individually sealed in one replaceable disk. The micro-dose delivery system uses only a small amount of excipient, such as 2-3mg lactose, thereby improving the drug delivery efficiency. The passive delivery method eliminates the need for coordination between breath and device actuation such as the pressure metered dose inhaler (pMDI). Finally, 14 doses on a disk reduce the need to frequently change dosage disks. In addition, each dose is effectively protected by a blister package to …

Design And Synthesis Of Novel Sultams As Non-Nucleoside Inhibitors Of Hiv Reverse Transcriptase, Brian Chadwick Lecroix

Doctoral Dissertations

The compound 2-methyl-3-phenyl-2,3-dihydro-1,2-benzisothiazole 1,1-dioxide (NSC 108406) was identified as an HIV-1 reverse transcriptase inhibitor by the National Cancer Institute. Using this lead, the Baker group has developed a series of analogues with various groups at the 3-position that show a spectrum of biological activities. In the end, the substituents used could not compare to the biological activity of the inhibitor efavirenz (Sustiva^® [trademark]), and so it was decided to synthesize sultams with alkylethynyl substituents at the 3-position of the sultams in an attempt to mimic the activity of efavirenz.

Previous research analyzed the proposed novel sultams in the modeling …

Safety And Immunoreactivity Of A Xenogeneic Dna Plasmid Vaccine Expressing Human Tyrosinase In Tumor-Bearing Horses, Luis Miguel Lembcke Perez Prieto

Doctoral Dissertations

Melanomas are among the most common skin tumors in horses (second only to sarcoids), with prevalence rates reaching as high as 80% in adult gray horses. Despite the wide availability of measures of local control, there are currently no systemic therapies that can effectively prevent spread, or treat metastatic or locally advanced/non-resectable melanoma in horses. A form of gene immunotherapy based on a plasmid DNA construct containing a xenogeneic form of the antigen tyrosinase have been developed and optimized for targeting cancer in both humans and dogs; and have demonstrated significant immunoreactivity and clinical benefit in the treatment of melanocytic …

Developing A Presumptive Test For Select Synthetic Cannabinoids, Carrie Snyder

Graduate Theses and Dissertations

Synthetic cannabinoids (SC's) began to gain popularity around the world in 2009. Since then, many of the compounds have been outlawed and methods developed to detect them and their metabolites using mass spectrometry. Our work investigated the possibility of developing a colorimetric presumptive test. The SC JWH-019 was synthesized and its ketone targeted as a possible reaction site. Many SC's contain ketones and thus a reaction at this site would be applicable to many of the compounds. Since JWH-019 is costly and time consuming to synthesize, much of the experimental work was done using benzophenone (BP). BP contains a diaryl …

Erg11-Mediated Azole Resistance In Candida Albicans, Stephanie Ann Flowers

Theses and Dissertations (ETD)

Although many medically important Candida species are commensal to the gut or colonizers of the skin, these organisms have the propensity to cause disease in the event of a waning immune system. Clinical manifestations of infections with Candida species can range from superficial mucosal infections to deep organ involvement usually resulting from haematogenous spread of infection. Despite significant progress made in the management of patients with fungal infections, the emergence of antifungal resistant clinical isolates creates significant problem in regards to antifungal prophylaxis and empirical treatment strategies. Antifungal resistance is associated with high mortality rates and hefty medical costs. The …

Full-Gestational Exposure To Nicotine And Ethanol Results In Long-Term Dysregulation In The Ventral Tegmental Area, Emily Elizabeth Roguski

Theses and Dissertations (ETD)

Nicotine is considered a gateway drug for other drugs of abuse. The majority of smokers that begin smoking in adolescence, continue into adulthood. Multiple factors have been linked with smoking initiation, including maternal smoking. Drug exposure during pregnancy has long been suspected to exert deleterious effects on the fetal brain. Concurrent use of smoking and drinking alcohol throughout pregnancy is an all too frequent occurrence in the human population especially in disadvantaged and younger women.

The present study investigated the potential contributing factors for the enhanced nicotine selfadministration as seen in offspring with gestational exposure to nicotine and ethanol (Nic+EtOH).* …

Radiosensitization Of Head & Neck Carcinoma Cells By Linifanib, A Receptor Tyrosine Kinase Inhibitor, Heng-Wei Hsu

Loma Linda University Electronic Theses, Dissertations & Projects

Tumor angiogenesis is a hallmark of advanced cancers and promotes invasion and metastasis. Over 90% of head and neck squamous cell carcinomas (HNSCC) express angiogenic factors such as vascular endothelial growth factor (VEGF). Since radiotherapy is one of the most commonly used treatments for HNSCC, it is imperative to identify the interactions between antiangiogenic therapy and radiotherapy, and to develop combination therapy to improve clinical outcome. The mechanisms between antiangiogenic agents and ionizing radiation are complicated and involve many interactions between the vasculature, tumor stroma and tumor cells. The proliferation and metastasis of tumor cells rely on angiogenesis/blood vessel formation. …

Formulation Development Of A Polymer-Drug Matrix With A Controlled Release Profile For The Treatment Of Glaucoma, Eric W. Tsoi

Master's Theses

Glaucoma is the leading cause of blindness in the United States accounting for 9-12% of all cases of blindness. Currently, the front line treatment for glaucoma are prostaglandins that may have to be taken up to several times a day. Even with proper treatment, roughly 11% of the patients using the treatment are non-compliant and lose their vision. In this project, ForSight Laboratories has developed a pharmaceutical drug delivering implant with the capability of sustaining long-term release of a prostaglandin as a new way to treat the condition. This project reports the product development of a polymer drug matrix with …

Bio-Identical Hormone Therapy: Understanding Women's Decision-Making Process And Family Physicians' Views, Lemmese Alwatban

Electronic Thesis and Dissertation Repository

This thesis explored women’s and family physicians’ experiences with Bio-identical Hormone Therapy (BHT). It aimed to develop a deeper understanding of women’s decision-making process in choosing this therapeutic modality, and the influence family physicians may have on this process. To capture the phenomenon under study, two complementary and sequential qualitative studies were conducted. The studies involved in-depth interviews with women using BHT and family physicians that care for this population. The collective findings of both studies demonstrated the complexity of menopause care. The findings illuminated the major factors involved in women’s BHT decision-making process. It also offered important information about …

Resveratrol Induced Apoptosis In A Human Adenosquamous Carcinoma Cell Line (Cal-27 Cells), Saquib A. Siddiqi

PCOM Biomedical Studies Student Scholarship

Radiotherapy and surgery are the two principal modalities in the treatment of head and neck cancers, and both therapies can result in severe adverse effects and ultimately lower the quality of life. It is of paramount importance to develop reagents that target the cancer cell specifically without affecting the normal non-cancer cells. Using the tongue cancer cell line Cal 27 as a model system, we dissected the molecular mechanism of the resveratrol-induced cancer cell apoptosis. After demonstrating that resveratrol induces the cancer cell apoptosis in a dose- and time-dependent manner, a systemic apoptosis protein array was conducted to identify the …

Kinetics And Mechanism Of S-Nitrosation And Oxidation Of Cysteamine By Peroxynitrite, Wilbes Mbiya

Dissertations and Theses

Cysteamine (CA), which is an aminothiol drug medically known as Cystagon® was studied in this thesis. Cysteamine was reacted with a binary toxin called peroxynitrite (PN) which is assembled spontaneously whenever nitric oxide and superoxide are produced together and the decomposition of peroxyinitrite was monitored. PN was able to nitrosate CA in highly acidic medium and excess CA to form S-nitrosocysteamine (CANO) in a 1:1 with the formation of one mole of CANO from one mole of ONOOH. In excess oxidant (PN) the following 1:2 stoichiometric ratio was obtained; ONOO^- + 2CA → CA-CA + NO2^- + H …

Effects Of Prenatal Testosterone On The Reproductive And Metabolic Neurons Of The Sheep Hypothalamus, Maria Cernea

Electronic Thesis and Dissertation Repository

Polycystic ovary syndrome (PCOS) is one of the most common endocrine disorders affecting reproductively aged women. Women with PCOS and ewes prenatally exposed to testosterone (T) show similar reproductive and metabolic defects, including anovulatory dysfunctions stemming from abnormal gonadotropin releasing hormone (GnRH) secretion and insulin resistance. For this dissertation, I examined the effects of prenatal T treatment on androgen receptor (AR) and insulin receptor (IR) expression with the reproductive and metabolic neurons of the hypothalamus, the ARC KNDy (co-expressing kisspeptin, neurokinin B/dynorphin), AgRP (agouti-related peptide) and proopiomelanocortin (POMC) neurons, and the preoptic area (POA) kisspeptin neurons, and the GnRH neurons. …

Functional Analysis Of Corazonin And Its Receptor In Drosophila Melanogaster, Kai Sha

Doctoral Dissertations

Corazonin (Crz) is an amidated undecapeptide originally isolated from the American cockroach. It has been shown to affect diverse physiological functions in a species-specific manner. However, the functionality of Crz in Drosophila melanogaster has not yet been determined. To gain insight into the role of Crz signaling in vivo, Crz and CrzR null alleles were obtained by transposable element mobilization. Flies carrying a deficiency uncovering Crz and pr-set7 loci were generated via P-element excision, and the latter was rescued by wild-type pr-set7 transgene. A mutation of Crz receptor (CrzR) was generated by Minos-element mobilization from …

Folate Receptor-Targeting Liposomes For The Delivery Of Antisense Molecules To Cancer Cells, Colin J. Way

Electronic Thesis and Dissertation Repository

RNAi (RNA interference) is emerging as a promising tool for cancer therapy. Small interfering RNA (siRNA) molecules are activated in that pathway to reduce specific tumour cell RNAs that mediate malignancy. SiRNA treatment has been primarily limited to in vitro studies: lack of efficient, preferential in vivo delivery to target cells remains a major obstacle. Many human tumours overexpress folate receptors (FR), and siRNA-mediated reduction of thymidylate synthase (TS) sensitizes tumour cells to anti-TS drugs. I developed a folate-containing cationic liposome to preferentially deliver anti-TS siRNA to FR-expressing human tumour cells. I show, in vitro, that liposome-encapsulated siRNA (but …

Developing Thyronamine Analog Pharmaceuticals Targeting Taar1 To Treat Methamphetamine Addiction, Troy Andrew Wahl

Dissertations and Theses

As a part of the overall program in the Grandy laboratory at Oregon Health & Science University (OHSU), studying the underlying chemical biology of methamphetamine (Meth) addiction, this dissertation reports on the development of six new thyronamine analogs which were synthesized and assayed against trace amine associated receptor 1 (TAAR1), giving preliminary results consistent with the analogs being inverse agonists. Due to highly variable TAAR1 expression levels in the assays, based on inter-assay response to control Meth stimulation as well as other possible factors, kinetic models were developed to qualitatively explain the assay results. The models set approximate limits on …

The Protumorigenic Role Of Caspase-8 In Neuroblastoma, Devin Drew Twitchell

Theses and Dissertations (ETD)

Neuroblastoma (NB), the most common extracranial solid tumor in children, accounts for 15% of cancer-related deaths in pediatric patients. Caspase-8 (casp8), a proapoptotic protein, is silenced in approximately, 50-70% of neuroblastoma patient samples. Loss of casp8 has been suggested to increase NB metastasis and correlated, in some studies, with advanced-stage NB. Furthermore, decreased casp8 expression may facilitate neuroblastoma tumorigenesis by protecting cells from cell death mediated by either integrins or chemotherapeutics. Paradoxically, casp8 expression is maintained in 30-50% of NB patient samples giving rise to the possibility that casp8 may provide selective advantages for NB tumorigenesis. Caspase-8 is shown to …

A Mathematical Model For Antibiotic Resistance In A Hospital Setting With A Varying Population, Edward H. Snyder

Electronic Theses and Dissertations

Antibiotic-resistant bacteria(ARB) is causing increased health risk and cost to society. Mathematical models have been developed to study the transmission of resistant bacteria and the efficacy of preventive measures to slow its spread within a hospital setting. The majority of these models have assumed a constant total hospital population with the admission and discharge rates being equal throughout the duration. But a typical hospital population varies from day to day and season to season. In this thesis, we apply variable admission and discharge daily rates to existing deterministic and stochastic models which examine the transmission of single and dual resistant …

Design, Synthesis And Development Of Transporter Targeting Agents For Image-Guided Therapy And Drug Delivery, Ning Tsao

Dissertations & Theses (Open Access)

The purpose of this study was to design, synthesize and develop novel transporter targeting agents for image-guided therapy and drug delivery. Two novel agents, N4-guanine (N4amG) and glycopeptide (GP) were synthesized for tumor cell proliferation assessment and cancer theranostic platform, respectively. N4amG and GP were synthesized and radiolabeled with ^99mTc and ⁶⁸Ga. The chemical and radiochemical purities as well as radiochemical stabilities of radiolabeled N4amG and GP were tested. In vitro stability assessment showed both ^99mTc-N4amG and ^99mTc-GP were stable up to 6 hours, whereas ⁶⁸Ga-GP was stable up to 2 hours. Cell culture studies …

Stimulation Through Tlr4 Increases Fviii Inhibitor Formation In A Mouse Model Of Hemophilia A, Claire K. Holley

Dissertations & Theses (Open Access)

Hemophilia A is a clotting disorder caused by functional factor VIII (FVIII) deficiency. About 25% of patients treated with therapeutic recombinant FVIII develop antibodies (inhibitors) that render subsequent FVIII treatments ineffective. The immune mechanisms of inhibitor formation are not entirely understood, but circumstantial evidence indicates a role for increased inflammatory response, possibly via stimulation of Toll-like receptors (TLRs), at the time of FVIII immunization. I hypothesized that stimulation through TLR4 in conjunction with FVIII treatments would increase the formation of FVIII inhibitors. To test this hypothesis, FVIII K.O. mice were injected with recombinant human FVIII with or without concomitant doses …

Comparison Of Methodologies For Synthesis Of 3-(Cyclopropylethynyl)Benzisothiazole 1,1-Dioxide, Rachel Lee Naramore

Chancellor’s Honors Program Projects

No abstract provided.

The Relationship Between Vitamin D Status Of Adult Women And Diet, Sun Exposure, Skin Reflectance, Body Composition, And Insulin Sensitivity, Marisa M. Mcadler

Master's Theses

As the prevalence of vitamin D deficiency continues to grow, mounting evidence supporting its link with chronic disease strengthens suggesting vitamin D’s candidacy in the prevention and treatment of multiple disease states and their complications. Dietary guidelines, however, do not take sun exposure into account. The present study sought to explore the impact of sun exposure on vitamin D status (serum 25(OH)D), and identify other significant determinants of serum levels which may have the greatest effects on overall health. Participants (n = 34) were pre-menopausal women aged 18 to 50 years (mean age 39 ± 6 years), who had their …

Development Of A Rapid Spme/Gc-Ms Method For The Detection And Quantification Of Synthetic Cathinones In Oral Fluid, David Correll

Senior Theses and Projects

The recent emergence and widespread abuse of new classes of compounds on the designer drug market as “legal” alternatives to scheduled drugs such as Ecstasy has prompted interest in the development of analytical methods for their detection and characterization. Synthetic cathinones, which are structurally similar to amphetamines, are commonly advertised as a “legal highs” or “herbal highs,” and are marketed under names such as “bath salts” and “plant food.” To avoid drug abuse legislation, a “not for human consumption” warning is typically printed on the label. Their ready availability on the Internet and in “head” shops, convenience stores, and even …

Norepinephrine Involvement In The Intermittent Swim Stress-Induced Deficit In Spatial Learning And Memory, Emily Elgert

Honors Theses and Capstones

Learning and memory impairments are often caused by stress disorders including depression. The present study investigated the involvement of norepinephrine in the swim stress-induced deficits of spatial learning and memory. Exposure to intermittent swim stress (ISS) followed by learning and memory tests in the Morris water maze (MWM) were used to investigate this relationship. The ISS paradigm consists of intermittent exposure to cold water, producing stress responses in rats. Reboxetine, a norepinephrine selective reuptake inhibitor (NSRI), was employed to investigate whether this compound reverses the ISS-induced deficit. In other words, rats exposed to the ISS, were hypothesized to experience impaired …

Synthesis And Spectroscopic Studies Of Substituted Pyrrolocytidines, Mckenry Charles

Electronic Thesis and Dissertation Repository

This thesis reports work in the area of modified nucleosides for potential use as molecular probes in nucleic acid chemistry. These heterocyclic base surrogates that are capable of canonical base pairing have use in the study of nucleic acid conformation, as reporters of the state of hybridization.^[1]

The synthesis of a 5-phenylpyrrolocytidine was attempted in order to compare its properties with its 6-substituted pyrrolocytidine counterpart. Unfortunately, the 5-substituted pyrrolocytidine was not achieved.

The synthesis of five nucleosides based on the pyrrolocytidine scaffold was reported. Their synthesis was achieved through the tandem Sonogashira/annulations reaction between 5-iodocytidine derivatives and …

Regulation Of Alpha Synuclein Following Chronic Methamphetamine Administration In Guinea Pigs: Correlation With Memory And Synaptic Plasticity, Adnouse Blanc

PCOM Biomedical Studies Student Scholarship

Methamphetamine (METH) is a highly addictive drug of abuse that has a severe impact on neuronal changes in the brain including modulations of plasticity, cognitive dysfunction, as well as memory impairment. These changes can be seen as modifications in the expression of biochemical markers associated with synaptic plasticity. One such marker associated with memory impairment is alpha synuclein (α-syn). Alteration of α-syn expression has been linked to memory impairment in patients with Alzheimer’s disease (AD) and Parkinson’s disease (PD). Here we assess the effect of chronic METH treatment in correlation to cognitive functions.

Twenty-nine guinea pigs (male, 150-250 g) were …

Does The Addition Of Muramyl Tripeptide To Chemotherapy Improve Overall Survival For Patients With Osteosarcoma?, Jennifer Jones

PCOM Physician Assistant Studies Student Scholarship

OBJECTIVE: The objective of this selective EBM review is to determine whether or not “Does the addition of muramyl tripeptide to chemotherapy improve overall survival for patients with osteosarcoma?”

STUDY DESIGN: Review of three English language primary randomized controlled trials published between 2005 and 2009.

DATA SOURCES: Randomized controlled trials evaluating the addition of muramyl tripeptide (MTP) to chemotherapy for patients with osteosarcoma were found using Medline/PubMed databases.

OUTCOMES MEASURED: Event-free survival (EFS) and overall survival were the outcome measures used to determine the effectiveness of the additional chemotherapy treatment in osteosarcoma patients. EFS was defined as …

Is Reduction Of Caffeine Intake Effective In Reducing The Symptoms Of Panic Attack In Panic Disorder Patients?, Elizabeth Wasson

PCOM Physician Assistant Studies Student Scholarship

OBJECTIVE: The objective for this selective EMB review is to determine whether or not the reduction of caffeine intake is effective in reducing the symptoms of panic attack in panic disorder patients.

STUDY DESIGN: Review of three English language randomized control trials published in 2007, 2008, and 2009.

DATA SOURCES: The double-blind placebo-controlled randomized control trials were obtained via PubMed.

OUTCOMES MEASURED: The prevalence of a clinical panic attack. Pre and post caffeine/placebo administration questionnaires were given to the participants. These surveys included the Subjective Units of Disturbance Scale (SUDS) and the Diagnostic Symptom Questionnaire (DSQ). …

Biosynthetic Pathway Of The Aminoribosyl Component Of Lipopeptidyl Nucleoside Antibiotics, Xiuling Chi

Theses and Dissertations--Pharmacy

Several lipopeptidyl nucleoside antibiotics that inhibit bacterial translocase I (MraY) involved in peptidoglycan cell wall biosynthesis contain an aminoribosyl moiety, an unusual sugar appendage in natural products. A-90289 and muraminomicin are the two representative antibiotics that belong to this family. Bioinformatic analysis of the biosynthetic A-90289 gene clusters revealed that five enzymes are likely involved in the assembly and attachment of the aminoribosyl unit. These enzymes of A-90289 are functionally assigned by in vitro characterization. The results reveal a unique ribosylation pathway that highlighted by uridine-5′-monophosphate as the source of the sugar, a phosphorylase strategy to generate a sugar-1-phosphate, and …

The Case For Extending Patent Terms For Drugs That Treat Rare Diseases, Joanna Louise Thompson

Electronic Theses and Dissertations

This paper seeks to determine if extended patent terms can positively effect the production of drugs that treat rare diseases. It reviews the structure of the modern pharmaceutical company and considers the regulatory history that lead to this structure. The paper applies historically significant economic research in the field of patents and considers patent alternatives to establish the best method for incentivizing the development of these drugs. The paper finds that while there are numerous pitfalls and issues with the patent method, there are no viable alternatives. It also concludes that extending patent terms for drugs that treat rare diseases …