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Full-Text Articles in Medicine and Health Sciences

Vitro Bacteriophage Treatment For A Staphylococcus Aureus And Pseudomonas Aeruginosa Co-Culture, Alexis Perry Mar 2024

Vitro Bacteriophage Treatment For A Staphylococcus Aureus And Pseudomonas Aeruginosa Co-Culture, Alexis Perry

Arkansas Women in STEM Conference

Recent studies show that up 27-36% of all infections are polymicrobial, involving more than one bacteria species. In all categories, polymicrobial infections are often more virulent and harmful to the patient. Since different types of bacteria can communicate with each other through quorum-sensing when in the presence of each other, they can display different genomic characteristics. Further research into polymicrobial infections needs to be done because these changing characteristics can prevent treatment from working, such as antibiotics or bacteriophage therapy. This experiment focused on the co-culture between the two bacteria, Pseudomonas aeruginosa and Staphylococcus aureus, which can be found co-existing …


Methionyl-Trna Synthetase Synthetic And Proofreading Activities Are Determinants Of Antibiotic Persistence, Whitney N. Wood, Miguel Angel Rubio, Lorenzo Eugenio Leiva, Gregory J. Phillips, Michael Ibba Mar 2024

Methionyl-Trna Synthetase Synthetic And Proofreading Activities Are Determinants Of Antibiotic Persistence, Whitney N. Wood, Miguel Angel Rubio, Lorenzo Eugenio Leiva, Gregory J. Phillips, Michael Ibba

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

Bacterial antibiotic persistence is a phenomenon where bacteria are exposed to an antibiotic and the majority of the population dies while a small subset enters a low metabolic, persistent, state and are able to survive. Once the antibiotic is removed the persistent population can resuscitate and continue growing. Several different molecular mechanisms and pathways have been implicated in this phenomenon. A common mechanism that may underly bacterial antibiotic persistence is perturbations in protein synthesis. To investigate this mechanism, we characterized four distinct metG mutants for their ability to increase antibiotic persistence. Two metG mutants encode changes near the catalytic site …


Interplay Of Periodontal Bacterial Metabolites In The Progression Of Coronary Artery Disease: A System Biological Approach, Janakiraman V Feb 2024

Interplay Of Periodontal Bacterial Metabolites In The Progression Of Coronary Artery Disease: A System Biological Approach, Janakiraman V

Annual Research Symposium

Purpose:

The purpose of this study is to investigate the intricate relationship between periodontal disease (PD) and coronary artery disease (CAD), as evidenced by epidemiological associations. Metalloproteinase inhibitor (TIMP1) plays a pivotal role in cellular signaling, differentiation, cell death, and migration by binding to target metalloproteinases, forming complexes with other molecules (collagenases) to inactivate them. However, the expression of TIMP1 is reduced in both PD and CAD, leading to an upregulation of other metalloproteinases. This research explores the hypothesis that metabolites released from (Porphyromonas gingivalis), a prevalent bacterium in atherosclerotic patients, may inhibit TIMP1, thereby influencing CAD progression. …


Reducing Food Scarcity: The Benefits Of Urban Farming, S.A. Claudell, Emilio Mejia Dec 2023

Reducing Food Scarcity: The Benefits Of Urban Farming, S.A. Claudell, Emilio Mejia

Journal of Nonprofit Innovation

Urban farming can enhance the lives of communities and help reduce food scarcity. This paper presents a conceptual prototype of an efficient urban farming community that can be scaled for a single apartment building or an entire community across all global geoeconomics regions, including densely populated cities and rural, developing towns and communities. When deployed in coordination with smart crop choices, local farm support, and efficient transportation then the result isn’t just sustainability, but also increasing fresh produce accessibility, optimizing nutritional value, eliminating the use of ‘forever chemicals’, reducing transportation costs, and fostering global environmental benefits.

Imagine Doris, who is …


Mutational Analysis Of The Nitrogenase Carbon Monoxide Protective Protein Cown Reveals That A Conserved C‑Terminal Glutamic Acid Residue Is Necessary For Its Activity, Dustin L. Willard, Joshuah J. Arellano, Mitch Underdahl, Terrence M. Lee, Avinash S. Ramaswamy, Gabriella Fumes, Agatha Kliman, Emily Y. Wong, Cedric P. Owens Dec 2023

Mutational Analysis Of The Nitrogenase Carbon Monoxide Protective Protein Cown Reveals That A Conserved C‑Terminal Glutamic Acid Residue Is Necessary For Its Activity, Dustin L. Willard, Joshuah J. Arellano, Mitch Underdahl, Terrence M. Lee, Avinash S. Ramaswamy, Gabriella Fumes, Agatha Kliman, Emily Y. Wong, Cedric P. Owens

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

Nitrogenase is the only enzyme that catalyzes the reduction of nitrogen gas into ammonia. Nitrogenase is tightly inhibited by the environmental gas carbon monoxide (CO). Many nitrogen fixing bacteria protect nitrogenase from CO inhibition using the protective protein CowN. This work demonstrates that a conserved glutamic acid residue near the C-terminus of Gluconacetobacter diazotrophicus CowN is necessary for its function. Mutation of the glutamic acid residue abolishes both CowN’s protection against CO inhibition and the ability of CowN to bind to nitrogenase. In contrast, a conserved C-terminal cysteine residue is not important for CO protection by CowN. Overall, this work …


Additive Effects Of Cyclic Peptide [R4w4] When Added Alongside Azithromycin And Rifampicin Against Mycobacterium Avium Infection, Melissa Kelley, Kayvan Sasaninia, Arbi Abnousian, Ali Badaoui, James Owens, Abrianna Beever, Nala Kachour, Rakesh Kumar Tiwari, Vishwanath Venketaraman Aug 2023

Additive Effects Of Cyclic Peptide [R4w4] When Added Alongside Azithromycin And Rifampicin Against Mycobacterium Avium Infection, Melissa Kelley, Kayvan Sasaninia, Arbi Abnousian, Ali Badaoui, James Owens, Abrianna Beever, Nala Kachour, Rakesh Kumar Tiwari, Vishwanath Venketaraman

Pharmacy Faculty Articles and Research

Mycobacterium avium (M. avium), a type of nontuberculous mycobacteria (NTM), poses a risk for pulmonary infections and disseminated infections in immunocompromised individuals. Conventional treatment consists of a 12-month regimen of the first-line antibiotics rifampicin and azithromycin. However, the treatment duration and low antibiotic tolerability present challenges in the treatment of M. avium infection. Furthermore, the emergence of multidrug-resistant mycobacterium strains prompts a need for novel treatments against M. avium infection. This study aims to test the efficacy of a novel antimicrobial peptide, cyclic [R4W4], alongside the first-line antibiotics azithromycin and rifampicin in reducing M. avium survival. Colony-forming unit (CFU) …


Evaluation Of The Virulence Potential Of Avian Pathogenic Escherichia Coli Isolated From Broiler Breeders With Colibacillosis In Mississippi, Jiddu Joseph Aug 2023

Evaluation Of The Virulence Potential Of Avian Pathogenic Escherichia Coli Isolated From Broiler Breeders With Colibacillosis In Mississippi, Jiddu Joseph

Theses and Dissertations

Avian pathogenic Escherichia coli (APEC) is a bacterium that is responsible for colibacillosis in birds. However, information about broiler breeder APEC isolates is limited, but the data is critical due to the transfer of this bacteria down the production pyramid to progenies resulting in high mortality. Therefore, we evaluated the phenotypic virulence characteristics of 28 isolates using embryo lethality and day-old chick challenge assays. Also, the in vitro adhesion and invasion potential of selected nine isolates were identified. Results showed more than 1/3rd of the isolates were highly virulent and the virulence increased as the number of virulence-associated genes …


Analyzing Pseudomonas Aeruginosa With Bacteriophage Tags Using Photoacoustic Flow Cytometry, Jennifer C. Schinke Aug 2023

Analyzing Pseudomonas Aeruginosa With Bacteriophage Tags Using Photoacoustic Flow Cytometry, Jennifer C. Schinke

Electronic Theses and Dissertations

The number of daily bacterial infections is climbing and the CDC explains that this is due to the antibiotic-resistant threat in the United States. Finding a faster way of bacterial identification is necessary as it currently takes 1-4 days for a medical lab to culture and identify bacteria. Photoacoustic flow cytometry (PAFC) can be used as an alternative method resulting in swift identification within an hour (Edgar, 2019). Pseudomonas aeruginosa, cell line PA01, will be coated in up to a few hundred red dyed phages making it detectible by the photoacoustic flow cytometry system. Bacteriophages (phages) are viruses that …


Microbe Hunters, Paul De Kruif Jul 2023

Microbe Hunters, Paul De Kruif

Zea E-Books Collection

Microbe Hunters by Paul de Kruif was first published in 1926 by Harcourt, Brace and Company, New York. It dramatically recounts the breakthrough discoveries of the fundamental elements of bacteriology. It features exciting profiles of Antony Leeuwenhoek, Lazzaro Spallanzani, Louis Pasteur, Robert Koch, Émile Roux, Emil Behring, Élie Metchnikoff, Theobald Smith, David Bruce, Ronald Ross, Battista Grassi, Walter Reed, and Paul Ehrlich. Their development of germ theory and its scientific proofs led to the first effective treatments for human diseases like anthrax, rabies, diptheria, malaria, sleeping sickness, syphilis, and yellow fever. They also made discoveries that saved the dairy, wine, …


A Review On Antibiotic Resistance And The Use Of Medicinal Plants In The Management Of Uropathogenic Bacteria, Hubza Ruatt Khan, Mehvish Javeed, Iqra Batool, Rabeea Anwar, Asma Ashraf, Sara Janiad Jun 2023

A Review On Antibiotic Resistance And The Use Of Medicinal Plants In The Management Of Uropathogenic Bacteria, Hubza Ruatt Khan, Mehvish Javeed, Iqra Batool, Rabeea Anwar, Asma Ashraf, Sara Janiad

Journal of Bioresource Management

UTIs are the most prevalent infections and are caused by uropathogenicmicrobes such as Escherichia coli, Klebsiella pneumoniae, Proteus mirabilis, Pseudomonas aeruginosa, Staphylococcus aureus, and Enterococcus spp. Antibiotic resistance has hampered the management of UTIs over the years, with direct repercussions on the treatment cost, the infection severity, and the duration of hospitalization. This review discussed the route of infections, risk factors connected to UTIs, antibiotic resistance issues as well as an alternative therapy to overcome the problem of antibiotic resistance. The medicinal plants which have been utilized for thousands of years to cure a variety of ailmentsrepresent a significant antibiotic …


The Pros Of Changing Trna Identity, Michael Ibba Jun 2023

The Pros Of Changing Trna Identity, Michael Ibba

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

The notion that errors in protein synthesis are universally harmful to the cell has been questioned by findings that suggest such mistakes may sometimes be beneficial. However, how often these beneficial mistakes arise from programmed changes in gene expression as opposed to reduced accuracy of the translation machinery is still unclear. A new study published in JBC shows that some bacteria have beneficially evolved the ability to mistranslate specific parts of the genetic code, a trait that allows improved antibiotic resistance.


Helices In Fluids And Their Applications, Eva M. Strawbridge May 2023

Helices In Fluids And Their Applications, Eva M. Strawbridge

Biology and Medicine Through Mathematics Conference

No abstract provided.


The Effects Of Light Intensity And Cell Structure On The Cultivation Of Arthrospira Platensis, Taylor Barnhart May 2023

The Effects Of Light Intensity And Cell Structure On The Cultivation Of Arthrospira Platensis, Taylor Barnhart

Honors Theses

As scientists explore further into space, more cost-effective resources are needed for long-term space travel. An interesting solution is Arthrospira platensis, a filamentous cyanobacteria high in proteins and nutrients, and known for its helical structure. In unfavorable conditions, coiled spirulina cells become straight. Spirulina converts carbon dioxide gas into pure oxygen and the different cell structures stimulate different responses in oxygen production and cultivation. In these experiments, 2.3 L containers of pure coiled spirulina and mixed (coiled and straight) spirulina were placed into 3 incubators with different light intensities: 51μmol/m2/s, 25μmol/m2/s, 12μmol/m2/s. Each experiment length was 72 hours and the …


Effect Of Temperature On The Microbiome Of A Laboratory Reared Colony Of Haemaphysalis Longicornis Ticks, Brianna Mitchell May 2023

Effect Of Temperature On The Microbiome Of A Laboratory Reared Colony Of Haemaphysalis Longicornis Ticks, Brianna Mitchell

Poster Presentations

Honors research poster.

Haemaphysalis longicornis is a species of tick native to eastern Asia, including eastern China, Japan, eastern Russia, and Korea. To date, it has invaded and has now established its existence in Australia, New Zealand, and several of the Pacific Islands. This species of tick has recently been introduced to the United States, having a confirmed sighting in November 2017 on a sheep farm in New Jersey and since establishing populations in 18 states along the east coast and Appalachia. Based on the existing locations of H. longicornis in its native regions, as well as in the United …


Determining The Effects Of Maternal Adiposity On Preterm Neonatal Microbiome And Short Chain Fatty Acid Profiles, Dalton James, William A. Clark Phd, Kristy L. Thomas May 2023

Determining The Effects Of Maternal Adiposity On Preterm Neonatal Microbiome And Short Chain Fatty Acid Profiles, Dalton James, William A. Clark Phd, Kristy L. Thomas

Undergraduate Honors Theses

The gut microbiota and its metabolites have vast impacts on the human digestive system, immune system, and health outcomes. Short chain volatile fatty acids (SCVFAs) present in feces can be representative of the interactions of the microbiota present in the gut. Low microbiota diversity in the human gut is highly associated with obesity and adverse health outcomes. Furthermore, the maternal microbiome has a direct impact on neonatal microbiota through various pathways such as environment, skin flora, breast milk composition, and vaginal secretions. This study is aimed to further understand the associations between various factors (maternal adiposity, gestational time, length of …


Role Of Pseudomonas Aeruginosa Exoenzymes S, T, And Y In The Modulation Of Intrinsic Apoptosis In Pulmonary Microvascular Endothelial Cells, Andrea M. Vavrinek May 2023

Role Of Pseudomonas Aeruginosa Exoenzymes S, T, And Y In The Modulation Of Intrinsic Apoptosis In Pulmonary Microvascular Endothelial Cells, Andrea M. Vavrinek

Honors Theses

P. aeruginosa is the most common cause of ventilator-associated pneumonia in ICU patients. P. aeruginosa uses a type III secretion system to inject exoenzymes S, T, U, and Y into host cells, exhibiting unique effects. Pulmonary microvascular endothelial cells (PMVECs) are used to evaluate cellular changes caused by exoenzymes. ExoY infection of PMVECs leads to cell rounding but does not lead to cell death, unlike ExoS/T. The current study evaluated the exoenzyme-induced modulation of intrinsic apoptosis in endothelial cells. Strain PAK, producing ExoS, T, and Y, was compared to isogenic strains expressing either S, SY, T, TY, Y, or none …


Development, Optimization, And In Vitro/In Vivo Evaluation Of Azelaic Acid Transethosomal Gel For Antidermatophyte Activity, Ali Nasr, Noha Badawi, Yasmine Tartor, Nader Sobhy, Ali Nasr Apr 2023

Development, Optimization, And In Vitro/In Vivo Evaluation Of Azelaic Acid Transethosomal Gel For Antidermatophyte Activity, Ali Nasr, Noha Badawi, Yasmine Tartor, Nader Sobhy, Ali Nasr

Pharmacy

Treatment of dermatophytosis is quite challenging. This work aims to investigate the antidermatophyte action of Azelaic acid (AzA) and evaluate its efficacy upon entrapment into transethosomes (TEs) and incorporation into a gel to enhance its application. Optimization of formulation variables of TEs was carried out after preparation using the thin film hydration technique. The antidermatophyte activity of AzA-TEs was first evaluated in vitro. In addition, two guinea pig infection models with Trichophyton (T.) mentagrophytes and Microsporum (M.) canis were established for the in vivo assessment. The optimized formula showed a mean particle size of 219.8 ± 4.7 nm and a …


The Effects Of Specialized Pro-Resolving Mediator Lipoxin A4 On Pseudomonas Aeruginosa Biofilms And Interactions With Monocytes, Julianne M. Thornton Apr 2023

The Effects Of Specialized Pro-Resolving Mediator Lipoxin A4 On Pseudomonas Aeruginosa Biofilms And Interactions With Monocytes, Julianne M. Thornton

Graduate School of Biomedical Sciences Theses and Dissertations

Pseudomonas aeruginosa (P. aeruginosa) is an opportunistic pathogen known as a major cause of hospital-acquired secondary infections, commonly causing chronic respiratory infections in immunocompromised individuals, especially those with cystic fibrosis, and often found in wound infections. P. aeruginosa uses the quorum sensing pathway to readily form protective biofilms, which reduce the efficacy of antibiotics and access by host immune cells to eradicate the pathogen. Specialized pro-resolving mediators (SPMs) are lipids endogenously produced by the host immune response to infection to aid in infection resolution. One SPM, Lipoxin A4 (LxA4), has been shown to be a robust quorum sensing inhibitor.

The …


Investigating The Antibacterial And Immunomodulatory Properties Of Lactobacillus Acidophilus Postbiotics, Rachael M. Wilson Apr 2023

Investigating The Antibacterial And Immunomodulatory Properties Of Lactobacillus Acidophilus Postbiotics, Rachael M. Wilson

Graduate School of Biomedical Sciences Theses and Dissertations

Probiotics are nonpathogenic microorganisms that have been extensively studied for their ability to prevent various infectious, gastrointestinal, and autoimmune diseases. The mechanisms underlying these probiotic effects have not been elucidated. However, we and other researchers have evidence suggesting that probiotic bacteria secrete metabolites that are antimicrobial and anti-inflammatory. As such, we developed a methodology to collect the secreted metabolites from a probiotic bacterium, Lactobacillus acidophilus, and tested this cell free filtrate (CFF) both in vitro and in vivo. Using this CFF, we have demonstrated that L. acidophilus secretes a molecule(s) that has specific bactericidal activity against the opportunistic pathogen, Pseudomonas …


Protocol To Identify The Core Gene Supported By An Essential Gene In E. Coli Bacteria Using A Genome-Wide Suppressor Screen, Isao Masuda, Ya-Ming Hou Mar 2023

Protocol To Identify The Core Gene Supported By An Essential Gene In E. Coli Bacteria Using A Genome-Wide Suppressor Screen, Isao Masuda, Ya-Ming Hou

Department of Biochemistry and Molecular Biology Faculty Papers

We describe here a genome-wide screening approach to identify the most critical core reaction among a network of many that are supported by an essential gene to establish cell viability. We describe steps for maintenance plasmid construction, knockout cell construction, and phenotype validation. We then detail isolation of suppressors, whole-genome sequencing analysis, and reconstruction of CRISPR mutants. We focus on E. coli trmD, which encodes an essential methyl transferase that synthesizes m1G37 on the 3'-side of the tRNA anticodon. For complete details on the use and execution of this protocol, please refer to Masuda et al. (2022).


The Immunomodulating Effects Of Delta-9 Tetrahydrocannabinol (Thc) And Cannabidiol (Cbd) In The Context Of Infection, Rose D. Goodman, Kate Rouse, Victor Jimenez Feb 2023

The Immunomodulating Effects Of Delta-9 Tetrahydrocannabinol (Thc) And Cannabidiol (Cbd) In The Context Of Infection, Rose D. Goodman, Kate Rouse, Victor Jimenez

Annual Research Symposium

No abstract provided.


Identification Of Novel Biosynthetic Gene Clusters Encoding For Polyketide/Nrps-Producing Chemotherapeutic Compounds From Marine-Derived Streptomyces Hygroscopicus From A Marine Sanctuary, Hannah Ruth Flaherty Jan 2023

Identification Of Novel Biosynthetic Gene Clusters Encoding For Polyketide/Nrps-Producing Chemotherapeutic Compounds From Marine-Derived Streptomyces Hygroscopicus From A Marine Sanctuary, Hannah Ruth Flaherty

Honors Theses and Capstones

Nearly one out of six deaths in 2020, around ten million people, were caused by cancer, making it a leading cause of death worldwide (WHO, 2022). This major public health issue, in addition to the rise of multidrug-resistant (MDR) pathogens, provides a high demand for the discovery of new pharmaceutical drugs to be used clinically to treat these conditions. The Streptomyces genus accounts to produce 39% of all microbial metabolites currently approved for human health, indicating its potential as an important species to study for antimicrobial and anticancer agents. The long linear genome of Streptomyces contains specialized sequences known as …


Probing The Porphyromonas Gingivalis Nitrosative Stress Response Network, Alexandra Galina Jan 2023

Probing The Porphyromonas Gingivalis Nitrosative Stress Response Network, Alexandra Galina

Theses and Dissertations

Objective: To persist in the oral cavity, the perio-pathogen Porphyromonas gingivalis must have an efficient nitrosative stress response mechanism. To better understand how P. gingivalis responds to nitrite (NO2-) we must determine what genes are involved in the nitrosative stress response network.

Methods: Through genomic screening, a list of genes was generated that were hypothesized to be part of the nitrosative stress response network and believed to be involved in nitrate/nitrite metabolism or redox state of the cells. Protein coding regions were replaced with the ermF sequence by allelic exchange mutagenesis. 15 mutants were created …


Comparing The Microbiomes Of Dental Plaques In 19th Century Ancestral Remains, Ananya Udyaver Jan 2023

Comparing The Microbiomes Of Dental Plaques In 19th Century Ancestral Remains, Ananya Udyaver

Undergraduate Research Posters

During the construction of VCU’s Hermes A. Kontos Medical Sciences Building in April 1994, nineteenth century ancestral remains were found in an abandoned well on the Medical College of Virginia (MCV) campus. This well, now known as the East Marshall Street Well (EMSW), is thought to have been used as a disposal location for cadaver dissection for surgical and other medical waste in the past. VCU is now seeking to use DNA sequencing technology to match and assemble bones from each individual for a proper burial, uncover the cultural and historical context in which these people lived, and bring a …


Identification Of The Type Eleven Secretion System (T11ss) And Characterization Of T11ss-Dependent Effector Proteins, Alex S. Grossman Dec 2022

Identification Of The Type Eleven Secretion System (T11ss) And Characterization Of T11ss-Dependent Effector Proteins, Alex S. Grossman

Doctoral Dissertations

Host-associated microbes live in dangerous environments as a result of host immune killing, nutrient provisioning, and physiological conditions. Bacteria have evolved a host of surface and secreted proteins to help interact with this host environment and overcome nutrient limitation. The studies included within this dissertation describe the identification of a novel bacterial secretion system which has evolved to transport these symbiosis mediating proteins. This system, termed the type eleven secretion system (T11SS), is present throughout the Gram negative phylum Proteobacteria, including many human pathogens such as Neisseria meningitidis, Acinetobacter baumanii, Haemophilus haemolyticus, and Proteus vulgaris. Furthermore, …


Occurrence Of Kanamycin-Resistant Bacteria Relative To Anthropogenic Pollution Along Richland Creek In Nashville, Tn​, Jolene Ho Mach, Annie Le, Brandon Torres Ramirez Nov 2022

Occurrence Of Kanamycin-Resistant Bacteria Relative To Anthropogenic Pollution Along Richland Creek In Nashville, Tn​, Jolene Ho Mach, Annie Le, Brandon Torres Ramirez

Science University Research Symposium (SURS)

The overuse of antibiotics has caused an increase in antibiotic-resistant (AR) bacteria, which is a serious public health concern. Previous studies showed a significant correlation between anthropogenic pollution and AR bacteria. This project aims to identify AR bacteria in Richland Creek relative to local anthropogenic pollution. Water samples were collected at four locations along Richland Creek in Nashville, Tennessee. Bacteria resistant to the antibiotic kanamycin were isolated from the water samples, identified to genera using DNA barcoding, and compared among the sites. We expect to see a greater abundance and diversity of kanamycin-resistant bacteria closer to the end than near …


Comparison Of The Humoral Immune Response Following Both Bacterial Challenge And Rnai Of Major Factors On Proliferation Of Bartonella Quintana In The Human Louse, Jake Zina Oct 2022

Comparison Of The Humoral Immune Response Following Both Bacterial Challenge And Rnai Of Major Factors On Proliferation Of Bartonella Quintana In The Human Louse, Jake Zina

Masters Theses

Human body lice, Pediculus humanus humanus, and head lice, Pediculus humanus capitis, have been hematophagous ectoparasites of humans for thousands of years. Despite being ecotypes, only body lice are known to transmit bacterial diseases to humans, and it appears that lower humoral and cellular immune responses allow body lice to possess a higher vector competence. We previously observed that the transcription level of the defensin 1 gene was up-regulated only in head lice following oral challenge of Bartonella quintana, a causative agent of trench fever, and also that body lice excreted more viable B. quintana in their …


Biomedical Applications Of Protein Films And Polymeric Nanomaterials, Sanjana Gopalakrishnan Oct 2022

Biomedical Applications Of Protein Films And Polymeric Nanomaterials, Sanjana Gopalakrishnan

Doctoral Dissertations

Biomaterials are widely applied for the diagnosis and treatment of numerous diseases. In addition to fulfilling specific biological functions, biomaterials must also be non-toxic, biocompatible, and sterilizable to be regarded as safe-for-use. Polymers are excellent candidates for fabricating functional biomaterials due to their wide availability and varied properties and may be natural or synthetic. Polymer precursors are fabricated into coatings, foams, scaffolds, gels, composites, and nanomaterials for several biomedical applications. This dissertation focuses on two types of polymeric biomaterials – protein-based materials and synthetic polymeric nanoparticles. Proteins are biopolymers that naturally occur with a variety of structural and functional properties. …


Cyclic Di-Gmp Regulates Motility, Biofilm Formation, And Desiccation Tolerance In Acinetobacter Baumannii, Garrett Reynolds Aug 2022

Cyclic Di-Gmp Regulates Motility, Biofilm Formation, And Desiccation Tolerance In Acinetobacter Baumannii, Garrett Reynolds

Electronic Theses and Dissertations

Acinetobacter baumannii is an increasingly multidrug-resistant pathogen contributing to hospital-acquired infections necessitating the discovery of novel treatments. A bacterial second messenger, cyclic diguanosine monophosphate (cyclic di-GMP), can regulate various persistence factors that are potentially advantageous for survival in hospital environments. Cyclic di-GMP–modulating enzymes and cyclic di-GMP–binding effectors predictively are encoded in the Acinetobacter baumannii genome. I hypothesized that cyclic di-GMP controls motility, biofilm formation, and desiccation tolerance in Acinetobacter baumannii. Disrupting cyclic di-GMP–modulating enzymes or cyclic di-GMP–binding effectors should alter the regulatory effectiveness of these phenotypes. I tested the multidrug-resistant isolate Acinetobacter baumannii strain AB5075 and identified several transposon …


Jatropha Tanjorensis A Flora Of Southeast Nigeria: Isolation And Characterization Of Naringenin And Validation Of Bio-Enhanced Synergistical Activity Of Α- Tocopherol Toward Clinical Isolates Of Resistant Bacterial, Ikechukwu Kingsley Ijoma, Vincent Ishmael Egbulefu Ajiwe Jun 2022

Jatropha Tanjorensis A Flora Of Southeast Nigeria: Isolation And Characterization Of Naringenin And Validation Of Bio-Enhanced Synergistical Activity Of Α- Tocopherol Toward Clinical Isolates Of Resistant Bacterial, Ikechukwu Kingsley Ijoma, Vincent Ishmael Egbulefu Ajiwe

Makara Journal of Science

Jatropha tanjorensis is among the rich floras of Southeast Nigeria and used by ethnic people to treat infections and manage health conditions. Ethnomedicine has long been employed in the treatment of ailments caused by bacterial pathogens. Studies showed that the incorporation of synthetic α-tocopherol to an antibacterial agent improves its activity. However, knowledge about the antibacterial-enhanced activity of plant-based α-tocopherols, especially those isolated from Jatropha tanjorensis, is limited because of the different bioactivities of synthetic and natural α-tocopherols. To determine the phytochemicals in J. tanjorensis, we carried out the structural elucidation of its leaf extracts. Naringenin and α-tocopherol …