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Strategies For Deriving A Single Measure Of The Overall Burden Of Antimicrobial Resistance In Hospitals, Alessandro Orlando

Theses and Dissertations

Background: Antimicrobial-resistant infections result in hospital stays costing between $18,000 and $29,000. As of 2009, Centers for Medicare and Medicaid Services no longer upgrade payments for hospital-acquired infections. Hospital epidemiologists monitor and document rates of individual resistant microbes in antibiogram reports. Overall summary measures capturing resistance within a hospital may be useful. Objectives: We applied four techniques (L1- and L2-principal component analysis (PCA), desirability functions, and simple summary) to create summary measures of resistance and described the four summary measures with respect to reliability, proportion of variance explained, and clinical utility. Methods: We requested antibiograms from hospitals participating in the …

When Volunteering Doesn’T Cut It: A Critical Examination Of Carbapenem-Resistant Enterobacteriaceae Surveillance And Trends In The United States., Erica E. Smith

Theses and Dissertations

Background. Carbapenem-resistant Enterobacteriaceae, including Escherichia coli and Klebsiella pneumoniae, are newly emerging pathogens of public health importance. Currently no nationally representative or mandatory surveillance or reporting system exists to examine trends of these important pathogens. Objective. The purpose of the current study was to estimate trends in overall microbial burden and carbapenem resistance in E. coli and K. pneumoniae and to understand the extent to which hospitals which report to voluntary surveillance systems represent all hospitals in the United States. Design. We conducted a descriptive study to compare the hospitals participating in voluntary reporting systems of the University HealthSystem Consortium …

Biobehavioral Mechanisms Of Emotion And Hiv Disease: Exploring Potential Mediators Of The Relation Between Trait Positive And Negative Affect And Hiv Health Status, Karen Stewart

Theses and Dissertations

Considerable research supports an association between negative psychosocial functioning and adverse health outcomes. The biobehavioral model is well supported and posits that these effects occur via alterations in physiological response and health damaging behaviors. Evidence is accumulating about potential benefits of positive psychosocial functioning; however, less is known about the mechanisms of these effects. The broaden-and-build model of positive emotions holds that positive emotions can undo the physiological and behavioral restrictions associated with negative emotions and promote resource development. The present correlational study sought to explore whether cortisol, medication adherence, and health behaviors (smoking, alcohol use, physical activity, and nutrition) …

Image Segmentation And Analysis For Automated Classification Of Traumatic Pelvic Injuries, Simina Vasilache

Theses and Dissertations

In the past decades, technical advances have allowed for the collection and storage of more types and larger quantities of medical data. The increase in the volume of existing medical data has increased the need for processing and analyzing such data. Medical data holds information that is invaluable for diagnostic as well as treatment planning purposes. Presently, a large portion of the data is not optimally used towards medical decisions because information contained in the data is inaccessible through simple human inspection, or traditional computational methods. In the field of trauma medicine, where caregivers are frequently confronted with situations where …

Characterization Of Adherence, Cytotoxicity And Biofilm Formation By Gardnerella Vaginalis, Jennifer Patterson

Theses and Dissertations

Worldwide, bacterial vaginosis (BV) is the most common vaginal disorder in women of childbearing age. BV is of major clinical importance due to its ability to significantly affect pregnancy outcome and enhance the transmission and acquisition of HIV. BV is characterized by a dramatic shift in the vaginal microflora; in most BV cases, the predominant bacterial species is Gardnerella vaginalis. It has been demonstrated that G. vaginalis forms an adherent biofilm on the vaginal epithelium of women with BV. Furthemore, evidence suggests that the high rate of recurrence associated with BV is related to incomplete eradication of the biofilm. The …

The Effect Of Implicit Stereotypes On The Physical Performance In Older Adults, Gabriele R. Moriello

Theses and Dissertations

The purpose of this study was to explore how stereotypes affect physical performance in older adults. A multigroup pretest post test design was utilized to determine whether implicit activation of positive or negative stereotypes has an effect on physical performance. Ninety six community dwelling older adults 65 years of age or older were included in the sample. Participants were randomly assigned to one of three groups: exposure to positive stereotypes of aging, exposure to negative stereotypes of aging, or a control condition. In order to simulate how older adults are exposed to stereotypes in real world settings, participants were primed …

Pooled Protein Immunization For Identification Of Cell Surface Antigens In Streptococcus Sanguinis, Xiuchun Ge, Todd Kitten, Cindy L. Munro, Daniel H. Conrad, Ping Xu

Philips Institute for Oral Health Research Publications

Background

Available bacterial genomes provide opportunities for screening vaccines by reverse vaccinology. Efficient identification of surface antigens is required to reduce time and animal cost in this technology. We developed an approach to identify surface antigens rapidly inStreptococcus sanguinis, a common infective endocarditis causative species.

Methods and Findings

We applied bioinformatics for antigen prediction and pooled antigens for immunization. Forty-seven surface-exposed proteins including 28 lipoproteins and 19 cell wall-anchored proteins were chosen based on computer algorithms and comparative genomic analyses. Eight proteins among these candidates and 2 other proteins were pooled together to immunize rabbits. The antiserum reacted …

Rifaximin Treatment In Hepatic Encephalopathy, Nathan M. Bass, Kevin D. Mullen, Arun J. Sanyal, Fred Poordad, Guy Neff, Carroll B. Leevy, Samuel Sigal, Muhammad Y. Sheikh, Kimberly Beavers, Todd Frederick, Lewis Teperman, Donald Hillebrand, Shirley Huang, Kunal Merchant, Audrey Shaw, Enoch Bortey, William P. Forbes

Internal Medicine Publications

Background

Hepatic encephalopathy is a chronically debilitating complication of hepatic cirrhosis. The efficacy of rifaximin, a minimally absorbed antibiotic, is well documented in the treatment of acute hepatic encephalopathy, but its efficacy for prevention of the disease has not been established.

Methods

In this randomized, double-blind, placebo-controlled trial, we randomly assigned 299 patients who were in remission from recurrent hepatic encephalopathy resulting from chronic liver disease to receive either rifaximin, at a dose of 550 mg twice daily (140 patients), or placebo (159 patients) for 6 months. The primary efficacy end point was the time to the first breakthrough episode …

Reversible Conformational Change In Herpes Simplex Virus Glycoprotein B With Fusion-From-Without Activity Is Triggered By Mildly Acidic Ph, Carlos R. Siekavizza-Robles, Stephen J. Dollery, Anthony V. Nicola

Microbiology and Immunology Publications

Background

The pre-fusion form of the herpes simplex virus (HSV) fusion protein gB undergoes pH-triggered conformational change in vitro and during viral entry (Dollery et al., J. Virol. 84:3759-3766, 2010). The antigenic structure of gB from the fusion-from-without (FFWO) strain of HSV-1, ANG path, resembles wild type gB that has undergone pH-triggered changes. Together, changes in the antigenic and oligomeric conformation of gB correlate with fusion activity. We tested whether the pre-fusion form of FFWO gB undergoes altered conformational change in response to low pH.

Results

A pH of 5.5 - 6.0 altered the conformation of Domains I and V …

Antibodies Against Multiple Merozoite Surface Antigens Of The Human Malaria Parasite Plasmodium Falciparum Inhibit Parasite Maturation And Red Blood Cell Invasion, Ute Woehlbier, Christian Epp, Fiona Hackett, Michael J. Blackman, Hermann Bujard

Microbiology and Immunology Publications

Background

Plasmodium falciparum merozoites expose at their surface a large protein complex, which is composed of fragments of merozoite surface protein 1 (MSP-1; called MSP-1₈₃, MSP-1₃₀, MSP-1₃₈, and MSP-1₄₂) plus associated processing products of MSP-6 and MSP-7. During erythrocyte invasion this complex, as well as an integral membrane protein called apical membrane antigen-1 (AMA-1), is shed from the parasite surface following specific proteolysis. Components of the MSP-1/6/7 complex and AMA-1 are presently under development as malaria vaccines.

Methods

The specificities and effects of antibodies directed against MSP-1, MSP-6, MSP-7 on the growth …

Virginia Commonwealth University Graduate And Professional Programs Bulletin Courses [2010], Virginia Commonwealth University

VCU Bulletins

Listing of professional and graduate courses for 2010-2011.

Berberine Inhibits Hiv Protease Inhibitor-Induced Inflammatory Response By Modulating Er Stress Signaling Pathways In Murine Macrophages, Weibin Zha, Guang Liang, Jian Xiao, Elaine Studer, Phillip B. Hylemon, William M. Pandak Jr., Guangji Wang, Xiaokun Li, Huiping Zhou

Microbiology and Immunology Publications

Background

HIV protease inhibitor (PI)-induced inflammatory response plays an important role in HIV PI-associated dyslipidemia and cardiovascular complications. This study examined the effect of berberine, a traditional herb medicine, on HIV PI-induced inflammatory response and further investigated the underlying cellular/molecular mechanisms in macrophages.

Methodology and Principal Findings

Cultured mouse J774A.1 macrophages and primary mouse macrophages were used in this study. The expression of TNF-α and IL-6 were detected by real-time RT-PCR and ELISA. Activations of ER stress and ERK signaling pathways were determined by Western blot analysis. Immunofluorescent staining was used to determine the intracellular localization of RNA binding protein …

Putative Cis-Regulatory Elements Associated With Heat Shock Genes Activated During Excystation Of Cryptosporidium Parvum, Benjamin Cohn, Patricio A. Manque, Ana M. Lara, Myrna G. Serrano, Nihar U. Sheth, Gregory A. Buck

Microbiology and Immunology Publications

Abstract

Background

Cryptosporidiosis is a ubiquitous infectious disease, caused by the protozoan parasitesCryptosporidium hominis and C. parvum, leading to acute, persistent and chronic diarrhea worldwide. Although the complications of this disease can be serious, even fatal, in immunocompromised patients of any age, they have also been found to lead to long term effects, including growth inhibition and impaired cognitive development, in infected immunocompetent children. The Cryptosporidium life cycle alternates between a dormant stage, the oocyst, and a highly replicative phase that includes both asexual vegetative stages as well as sexual stages, implying fine genetic regulatory mechanisms. The …

Parametric Frailty Models For Clustered Data With Arbitrary Censoring: Application To Effect Of Male Circumcision On Hpv Clearance, Xiangrong Kong, Kellie Archer, Lawrence H. Moulton, Ronald H. Gray, Mei-Cheng Wang

Biostatistics Publications

Background

In epidemiological studies, subjects are often followed for a period during which study outcomes are measured at selected time points, such as by diagnostic testing performed on biological samples collected at each visit. Although test results may indicate the presence or absence of a disease or condition, they cannot provide information on when exactly it occurred. Such study designs generate arbitrarily censored time-to-event data, which can include left, interval and right censoring. Adding to this complexity, the data may be clustered such that observations within the same cluster are not independent, such as time to recovery of an infectious …

Antibiotic Use By Members Of The American Association Of Endodontics: A National Survey For 2009- A Follow Up From The Report In 1999, Pye Kyu

Theses and Dissertations

The purpose of this study was to determine the changes in prescribing habits of active members of American Association of Endodontics (AAE) with regards to antibiotics in comparison to the findings reported by Yingling et al. in 1999. The invitations to take the online survey were sent via email to 2593 active members. A response rate of 37.75% was obtained. It was determined to be adequate for analysis and for comparison to the results obtained by Yingling et al. Comparisons between the percentages shown in this survey and the previous survey were tested using a z-test. An ANOVA model was …

Examining The Association Of Fruit And Vegetable Intake And Breast And Prostate Cancer Screening, Mark Yu

Theses and Dissertations

Breast and prostate cancer incidence and mortality have been steadily decreasing. Reasons for these reductions may be related to increased rates of cancer screening and other factors such as improvements in diet, including consumption of fruits and vegetables. We wanted to determine if individuals who get screened for breast and prostate cancer are more or less likely to consume adequate servings of fruit and vegetables. A cross-sectional study using the BRFSS survey was conducted. Individuals included in this study (n=26,222), were asked about their breast or prostate cancer screening history. They were also asked about their servings per day of …

The 2009 H1n1 Influenza A “Swine Flu” Virus Presentation In Virginia 2009, Tammie Smith

Theses and Dissertations

Objective: 2009 H1N1 influenza was first detected in the Northern Hemisphere in April 2009. National data have suggested that the novel influenza virus disproportionately causes severe illness in children and young adults, a somewhat different presentation from traditional seasonal flu which normally strikes hardest in the very young and older adults. This may or may not be the case in Virginia, which, if it is different, may suggest a need to alter flu prevention messages and vaccine policy as the outbreak continues through the fall 2009-10 influenza season. This report examined the early presentation of the new influenza virus in …

Commonwealth Times 2009-12-03 [Front Page Has 2009-11-30]

Commonwealth Times, 1969-

No abstract provided.

Histone Deacetylase Inhibitors And Innate Immunity In Septic Shock, Joseph Bertsche

Theses and Dissertations

Innate immunity depends on pattern recognition receptors, which recognize pathogen associated molecular patterns (PAMPS), such as Toll-like receptor 4 (TLR4), which detects the gram-negative bacterial toxin, lipopolysaccharide. Engagement of TLR4 by LPS sets off a cascade ending in the activation of pro-inflammatory cytokines and interferon-β (IFN-β) which alerts the host to the infection. However, these responses can be mal-adaptive, especially in the context of bacterial sepsis, where a "cytokine storm" results in death of the host. Pharmacological modulation of these responses may therefore be a promising treatment modality. Inhibition of classic pro-inflammatory cytokines such as IL-1β and TNF-α has been …

Examining The Effects Of Penning On Juvenile Eastern Box Turtles (Terrapene Carolina Carolina), Nicolas Frederick

Theses and Dissertations

Box turtle (Terrapene carolina) populations have been declining over the last several decades, and one major cause is increasing urbanization. As a result of habitat fragmentation, wildlife managers are frequently turning to new and alternative management strategies. Traditional box turtle management has included relocation, which has been met with limited success. This study aims to combine these strategies with another less-studied one: forcing turtles to overwinter on site by penning them in an outdoor enclosure. Two sets of juvenile box turtles were released at the Virginia Commonwealth University Rice Center: one penned on site in a pen for one year, …

Shafer Court Connections (2009-09)

Shafer Court Connections, 1994-2010

For alumni of the Academic Campus of Virginia Commonwealth University.

Frequency Of Tlr-2, 4, 9 And Cd14 Polymorphisms In Aggressive Periodontitis Population In African-Americans, Melanie Chou

Theses and Dissertations

Aim: The aim of this study is to determine the frequency of single nucleotide polymorphisms (SNPs) in various pattern recognition receptor (PRR) genes, including Toll like receptors (TLR) -2, -4, -9, and CD14 in chronic (CP), localized (LAP) and generalized aggressive (GAP) periodontitis and periodontally healthy (NP) patients in an African American population. Methods: A total of 205 subjects were involved in the study. The LAP group consists of 25 subjects, the GAP group 50 subjects, the CP group 73 subjects and the NP group 57subjects. Genotyping was performed in TLR2 (G2408A), TLR4 (A896G),TLR9 (T1486C) and CD14 (C260T) genes by …

Determinants Of Hepatitis B Vaccination Among Adults In The United States: Nhanes 1999-2006, Conschetta Wright

Theses and Dissertations

Purpose: The primary objective of this study was to estimate the prevalence of vaccination and HBV infection status of adults and to evaluate the trend in self reported vaccination and seroprevalence for Hepatitis B for this population. Additionally, this study sought to assess the association between vaccination rates, seroprevalence (HBsAg, anti-HBc, and anti-HBs), demographic (age, gender, location of birth, race/ethnicity), and socioeconomic (annual household income, education level, insurance coverage and access to care, marital status) characteristics. Methods: Eight years, 1999-2006, of the National Health and Nutrition Examination Survey (NHANES) data were used. NHANES participants aged 20-59 years who contributed data …

Interpersonal And Shared Decision Making Models Of Communication Applied To Simulated Requests For Organ Donation, Daniel Baughn

Theses and Dissertations

Using an analogue format, the present study evaluated the viability of relationship and interactional concepts that have been applied to the physician-patient interaction to the field of organ donation by examining the donation request process between procurement coordinators and simulated families. Interpersonal processes were assessed using behavioral ratings by independent observers. Procurement coordinators were viewed as being more submissive than dominant and more friendly than hostile. Family members were viewed as being more hostile than friendly, more dominant and hostile than submissive or friendly, disclosing slightly more personal information than medical information, and engaging in slightly more shared decision making …

A Mathematical Model For Anti-Malarial Drug Resistance, Amanda Matthews

Theses and Dissertations

Despite the array of medical advances of our modern day society, infectious diseases still plague millions of people worldwide. Malaria, in particular, causes substantial suffering and death throughout both developed and developing countries. Aside from the socioeconomic challenges presented by the disease's prevalence in impoverished nations, one of the major difficulties scientists have encountered while attempting to eradicate the disease is the parasite's ability to become resistant to new drugs and methods of treatment. In an effort to better understand the dynamics of malaria, we analyze a mathematical model that accounts for both the treatment aspect as well as the …

The Economic Impact Of Antimicrobial Resistance In Patients With Nosocomial Staphylococcus Aureus Bacteremia, Suzanne Phillips

Theses and Dissertations

Background: The proportion of nosocomial Staphylococcus infections caused by methicillin-resistant Staphylococcus aureus (MRSA) has increased from 22% in 1995 to 63% in 2004. Blood stream infections, more commonly referred to as bacteremias, represented the majority (75.5%) of hospital-onset MRSA cases. The economic impact of Staphylococcus aureus bacteremia merits investigation. Methods: This was a retrospective cohort analysis within Cerner HealthFacts data warehouse. Eligible patients were those who had Staphylococcus aureus bacteremia and were discharged between January 1, 2000, and December 31, 2006. Inclusion criteria include age > 18 years old and onset of infection > 48 hours post admission. The crude association was …

The Presence Of Amphibian Ranavirus In Virginia Warm Water Fish Hatchery Ponds, Elizabeth Nelson

Theses and Dissertations

Amphibian declines have been occurring world wide over the past several decades. Infectious disease and environmental changes have been implicated as the causative agents in these declines. Fish stocking from hatcheries provides a unique opportunity for organisms, including infectious diseases, to travel over long distances. Ranavirus was previously found in two ponds at Harrison Lake National Fish Hatchery in Charles City County, Virginia. Therefore, the primary objective of this study was to determine if ranavirus is present in tadpoles from four warm water fish hatcheries in Virginia. A secondary objective of this study was to determine if there are relationships …

Identification Of Binding Partners Of A Novel P. Falciparum Exported Protein, Monica Zapata

Theses and Dissertations

Plasmodium falciparum is the causative agent of the most severe form of malaria. This parasite drastically modifies its host cell, the erythrocyte, to create a hospitable environment for its growth and reproduction. In order for these modifications to occur, the parasite secretes proteins into the erythrocyte. While the secretion machinery is still unknown, many secreted proteins have been found to have a hydrophobic signal sequence and a novel host-targeting signal downstream of the hydrophobic sequence. A novel P. falciparum protein has been shown to be secreted from the parasitophorous vacuole, yet it lacks both a hydrophobic signal sequence and a …

Preventive Dental Services For Infants And Subsequent Utilization Of Dental Services, Elizabeth Berry

Theses and Dissertations

The purpose of this study was to examine the use of dental services for young children following a preventive oral health intervention in a pediatric medical clinic. Over a 3 year period (2005-2008), children 0-36 months of age, enrolled in Medicaid, were provided preventive oral health services in a medical setting. Descriptive statistics and multivariate logistic regression were used to determine the effect receiving the preventive oral health services in a medical setting with the outcomes of dental utilization. 15% were determined to have dental caries at the intervention and 42% found to have a dental visit post-intervention. Children determined …

Diagnosis Of Infections Caused By Pathogenic Free-Living Amoebae, Bruno Da Rocha-Azevedo, Herbert B. Tanowitz, Francine Marciano-Cabral

Microbiology and Immunology Publications

Naegleria fowleri, Acanthamoeba spp., Balamuthia mandrillaris, and Sappinia sp. are pathogenic free-living amoebae. N. fowleri causes Primary Amoebic Meningoencephalitis, a rapidly fatal disease of the central nervous system, whileAcanthamoeba spp. and B. mandrillaris cause chronic granulomatous encephalitis.Acanthamoeba spp. also can cause cutaneous lesions and Amoebic Keratitis, a sight-threatening infection of the cornea that is associated with contact lens use or corneal trauma. Sappinia pedata has been identified as the cause of a nonlethal case of amoebic encephalitis. In view of the potential health consequences due to infection with these amoebae, rapid diagnosis is critical for early treatment. Microscopic examination and …