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8,150 full-text articles. Page 274 of 311.

Clade C Hiv-1 Isolates Circulating In Southern Africa Exhibit A Greater Frequency Of Dicysteine Motif-Containing Tat Variants Than Those In Southeast Asia And Cause Increased Neurovirulence, Vasudev R. Rao, Ujjwal Neogi, Joshua S, Talboom, Ligia Padilla, Mustafizur Rahman, Cari Fritz-French, Sandra Gonzalez-Ramirez, Anjali Verma, Charles Wood, Ruth M. Ruprecht, Udaykumar Ranga, Tasnim Azim, Vinayaka R. Prasad 2013 Albert Einstein College of Medicine

Clade C Hiv-1 Isolates Circulating In Southern Africa Exhibit A Greater Frequency Of Dicysteine Motif-Containing Tat Variants Than Those In Southeast Asia And Cause Increased Neurovirulence, Vasudev R. Rao, Ujjwal Neogi, Joshua S, Talboom, Ligia Padilla, Mustafizur Rahman, Cari Fritz-French, Sandra Gonzalez-Ramirez, Anjali Verma, Charles Wood, Ruth M. Ruprecht, Udaykumar Ranga, Tasnim Azim, Vinayaka R. Prasad

Nebraska Center for Virology: Faculty Publications

Background: HIV-1 Clade C (Subtype C; HIV-1C) is responsible for greater than 50% of infections worldwide. Unlike clade B HIV-1 (Subtype B; HIV-1B), which is known to cause HIV associated dementia (HAD) in approximately 15% to 30% of the infected individuals, HIV-1C has been linked with lower prevalence of HAD (0 to 6%) in India and Ethiopia. However, recent studies report a higher prevalence of HAD in South Africa, Zambia and Botswana, where HIV-1C infections predominate. Therefore, we examined whether Southern African HIV-1C is genetically distinct and investigated its neurovirulence. HIV-1 Tat protein is a viral determinant of neurocognitive dysfunction. …


Global Neuroaids Roundtable, Jeymohan Joseph, Cristian L. Achim, Michael J. Boivin, Bruce J. Brew, David B. Clifford, Deborah A. Colosi, Ronald J. Ellis, Robert K. Heaton, Amadou Gallo-Diop, Igor Grant, Georgette D. Kanmogne, Mahendra Kumar, Scott Letendre, Thomas D. Marcotte, Avindra Nath, Carlos A. Pardo, Robert H. Paul, Lynn Pulliam, Kevin Robertson, Walter Royal III, Ned Sacktor, Pasiri Sithinamsuwan, Davey M. Smith, Victor Valcour, Brian Wigdahl, Charles Wood 2013 National Institutes of Health

Global Neuroaids Roundtable, Jeymohan Joseph, Cristian L. Achim, Michael J. Boivin, Bruce J. Brew, David B. Clifford, Deborah A. Colosi, Ronald J. Ellis, Robert K. Heaton, Amadou Gallo-Diop, Igor Grant, Georgette D. Kanmogne, Mahendra Kumar, Scott Letendre, Thomas D. Marcotte, Avindra Nath, Carlos A. Pardo, Robert H. Paul, Lynn Pulliam, Kevin Robertson, Walter Royal Iii, Ned Sacktor, Pasiri Sithinamsuwan, Davey M. Smith, Victor Valcour, Brian Wigdahl, Charles Wood

Nebraska Center for Virology: Faculty Publications

In May 2012, the Division of AIDS Research at the National Institute of Mental Health (NIMH) organized the “Global NeuroAIDS Roundtable” in conjunction with the 11th International Symposium on Neurovirology and the 2012 Conference on HIV in the Nervous System. The meeting was held in New York, NY, USA and brought together NIMH-funded investigators who are currently working on projects related to the neurological complications of AIDS (NeuroAIDS) in Africa, Asia, Eastern Europe, and Latin America in order to provide an opportunity to share their recent findings and discuss the challenges encountered within each country. The major goals of the …


Extracellular Proteases Are Key Mediators Of Staphylococcus Aureus Virulence Via The Global Modulation Of Virulence-Determinant Stability, Stacey L. Kolar, J. Antonio Ibarra, Frances E. Rivera, Joe M. Mootz, Jessica E. Davenport, Stanley M. Stevens Jr., Alexander R. Horswill, Lindsey N. Shaw 2013 University of South Florida

Extracellular Proteases Are Key Mediators Of Staphylococcus Aureus Virulence Via The Global Modulation Of Virulence-Determinant Stability, Stacey L. Kolar, J. Antonio Ibarra, Frances E. Rivera, Joe M. Mootz, Jessica E. Davenport, Stanley M. Stevens Jr., Alexander R. Horswill, Lindsey N. Shaw

Molecular Biosciences Faculty Publications

Staphylococcus aureus is a highly virulent and successful pathogen that causes a diverse array of diseases. Recently, an increase of severe infections in healthy subjects has been observed, caused by community-associated methicillin-resistant S. aureus (CA-MRSA). The reason for enhanced CA-MRSA virulence is unclear; however, work suggests that it results from hypersecretion of agr-regulated toxins, including secreted proteases. In this study, we explore the contribution of exo-proteases to CA-MRSA pathogenesis using a mutant lacking all 10 enzymes. We show that they are required for growth in peptide-rich environments, serum, in the presence of antimicrobial peptides (AMPs), and in human blood. …


A Transient Α-Helical Molecular Recognition Element In The Disordered N-Terminus Of The Sgs1 Helicase Is Critical For Chromosome Stability And Binding Of Top3/Rmi1, Jessica A. Kennedy, Gary W. Daughdrill, Kristina H. Schmidt 2013 University of South Florida

A Transient Α-Helical Molecular Recognition Element In The Disordered N-Terminus Of The Sgs1 Helicase Is Critical For Chromosome Stability And Binding Of Top3/Rmi1, Jessica A. Kennedy, Gary W. Daughdrill, Kristina H. Schmidt

Molecular Biosciences Faculty Publications

The RecQ-like DNA helicase family is essential for the maintenance of genome stability in all organisms. Sgs1, a member of this family in Saccharomyces cerevisiae, regulates early and late steps of double-strand break repair by homologous recombination. Using nuclear magnetic resonance spectroscopy, we show that the N-terminal 125 residues of Sgs1 are disordered and contain a transient α-helix that extends from residue 25 to 38. Based on the residue-specific knowledge of transient secondary structure, we designed proline mutations to disrupt this α-helix and observed hypersensitivity to DNA damaging agents and increased frequency of genome rearrangements. In vitro binding assays …


Identification Of Proteins At Active, Stalled, And Collapsed Replication Forks Using Isolation Of Proteins On Nascent Dna (Ipond) Coupled With Mass Spectrometry, Bianca M. Sirbu, W. Hayes McDonald, Huzefa Dungrawala, Akosua Badu-Nkansah, Gina M. Kavanaugh, Yaoyi Chen, David L. Tabb, David Cortez 2013 Vanderbilt University School of Medicine

Identification Of Proteins At Active, Stalled, And Collapsed Replication Forks Using Isolation Of Proteins On Nascent Dna (Ipond) Coupled With Mass Spectrometry, Bianca M. Sirbu, W. Hayes Mcdonald, Huzefa Dungrawala, Akosua Badu-Nkansah, Gina M. Kavanaugh, Yaoyi Chen, David L. Tabb, David Cortez

Molecular Biosciences Faculty Publications

Both DNA and chromatin need to be duplicated during each cell division cycle. Replication happens in the context of defects in the DNA template and other forms of replication stress that present challenges to both genetic and epigenetic inheritance. The replication machinery is highly regulated by replication stress responses to accomplish this goal. To identify important replication and stress response proteins, we combined isolation of proteins on nascent DNA (iPOND) with quantitative mass spectrometry. We identified 290 proteins enriched on newly replicated DNA at active, stalled, and collapsed replication forks. Approximately 16% of these proteins are known replication or DNA …


Cpg And Interleukin-15 Synergize To Enhance Ifn-Gamma Production By Activated Cd8(+) T Cells, Dustin Cobb, Sigi Guo, Ronald B. Smeltz 2013 Old Dominion University

Cpg And Interleukin-15 Synergize To Enhance Ifn-Gamma Production By Activated Cd8(+) T Cells, Dustin Cobb, Sigi Guo, Ronald B. Smeltz

Bioelectrics Publications

Interleukin-15 (IL-15) regulates the development and maintenance of memory CD8(+) T cells. Paradoxically, we previously reported that IL-15 could enhance CD8(+) T-cell responses to IL-12, a proinflammatory cytokine required for optimal priming of effector CD8(+) T cells. To expand the physiological relevance of these findings, we tested IL-15 for its ability to enhance T-cell responses to bacterial CpG. Expectedly, CpG enhanced the production of IFN-gamma by CD8(+) T cells polyclonally activated with anti-CD3. However, addition of IL-15 to CpG-stimulated cultures led to a striking increase in IFN-gamma production. The effect of CpG and IL-15 was also evident with CD8(+) T …


Resolving The Nutritional Requirements Of The Bile Acid-Dehydroxylating Gut Bacterium Clostridium Scindens, Oindrila Paul 2013 Eastern Illinois University

Resolving The Nutritional Requirements Of The Bile Acid-Dehydroxylating Gut Bacterium Clostridium Scindens, Oindrila Paul

Masters Theses

Compared to the other parts of the human body, the gastrointestinal tract harbors a complex microbiota. The impact of the indigenous microbiota on host physiology is most pronounced in the colon, where the primary bile acids chenodeoxycholic acid and cholic acid are converted, via 7α-dehydroxylation, to the toxic secondary bile acids lithocholic acid and deoxycholic acid, respectively, by Clostridium scindens, an obligate anaerobe. Interestingly, other than bile acid dehydroxylation, little is known about the basic physiology of C. scindens. Understanding the metabolism of C. scindens will hopefully provide much-needed information as to how this gut bacterium impacts human health and …


Optimizing Electrode Design For Microbial Fuel Cells Used For Wastewater Treatment, Lindsay Nichols, John A. Hogan 2013 NASA Ames Research Center

Optimizing Electrode Design For Microbial Fuel Cells Used For Wastewater Treatment, Lindsay Nichols, John A. Hogan

STAR Program Research Presentations

Microbial fuel cells (MFC) utilize bacteria to generate an electrical current that can be used in the decomposition of sludge and human urine. In a MFC there is an anode (for oxidation of organic compounds), cathode (reduction of oxygen or carbon dioxide), and a proton exchange membrane (PEM, allows protons to migrate); reduction-oxidation reactions between the anode and cathode produce a measurable current. Bacteria that are found in sludge can be used to produce electrons in a voltaic cell, but optimizing conditions for harnessing the energy is crucial to making a MFC efficient. Research has shown that the ratios of …


Non-Cytotoxic Antibacterial Silver–Coumarin Complex Doped Sol–Gel Coatings, Swarna Jaiswal, Kunal Bhattacharya, Maeve Sullivan, Maureen Walsh, Bernadette Creaven, Fathima Laffir, Brendan Duffy, Patrick McHale 2013 Technological University Dublin

Non-Cytotoxic Antibacterial Silver–Coumarin Complex Doped Sol–Gel Coatings, Swarna Jaiswal, Kunal Bhattacharya, Maeve Sullivan, Maureen Walsh, Bernadette Creaven, Fathima Laffir, Brendan Duffy, Patrick Mchale

Articles

Microbial colonisation on clinical and industrial surfaces is currently of global concern and silane based sol–gel coatings are being proposed as potential solutions. Sol–gels are chemically inert, stable and homogeneous and can be designed to act as a reservoir for releasing antimicrobial agents over extended time periods. In the present study, silver nitrate (AgN) and a series of silver coumarin complexes based on coumarin-3-carboxylatosilver (AgC) and it is 6,7 and 8 hydroxylated analogues (Ag6, Ag7, Ag8) were incorporated into sol–gel coatings. The comparative antibacterial activity of the coatings was determined against meticillin resistant Staphylococcus aureus (MRSA) and multidrug resistance Enterobacter …


Microfluidic-Assisted Atomic Force Microscopy For The Mechanical Characterization Of Soft Biological Materials, Aaron Peter Mosier 2013 University at Albany, State University of New York

Microfluidic-Assisted Atomic Force Microscopy For The Mechanical Characterization Of Soft Biological Materials, Aaron Peter Mosier

Legacy Theses & Dissertations (2009 - 2024)

Viable methods for bacterial biofilm remediation require a fundamental understanding of biofilm mechanical properties and their dependence on dynamic environmental conditions. Mechanical test data, quantifying elasticity or adhesion, may be used to perform physical modeling of biofilm behavior, thus enabling the development of novel remediation strategies. To achieve real-time, dynamic measurements of these properties, a novel analysis platform consisting of a microfluidic flowcell device has been designed and fabricated for in situ analysis using atomic force microscopy (AFM) and confocal laser scanning microscopy (CLSM). The flowcell consists of microfluidic channels for biofilm establishment that are then converted into an open …


Arbovirus Persistence And Selection Of Persistent Variants Following Chronic Infection In Aedine Mosquitoes: A Comparative Study Between Ae. Aegypti And Ae. Albopictus 30 Days Post Infection With Sindbis Virus, Zoe Leah Lyski 2013 University of North Florida

Arbovirus Persistence And Selection Of Persistent Variants Following Chronic Infection In Aedine Mosquitoes: A Comparative Study Between Ae. Aegypti And Ae. Albopictus 30 Days Post Infection With Sindbis Virus, Zoe Leah Lyski

UNF Graduate Theses and Dissertations

In the present investigation two container breeding mosquitoes, Aedes aegypti and Aedes albopictus were exposed to Sindbis virus (SINV). Mosquitoes were proffered a viremic bloodmeal using a vertical membrane feeder in an attempt to infect females while preserving virus-gut interactions that are speculated to be responsible for amplification and selective roles encountered in nature. Cohorts of 50 mosquitoes of each species were exposed to SINV strain TR339 or EMEM in a bloodmeal and incubated in insectary conditions for 30 days. Once infected, the mosquito remains persistently infected for life, accumulating mutations in the virus RNA genome. Plaque size variants may …


Evading Innate And Adaptive Immunity During Adenovirus Cell Entry, Shauna Marvin 2013 Loyola University Chicago

Evading Innate And Adaptive Immunity During Adenovirus Cell Entry, Shauna Marvin

Dissertations

Adenovirus (Ad), a non-enveloped, dsDNA virus, enters cells via clathrin-mediated endocytosis. For viral genome delivery to the nucleus, Ad must penetrate endosomal membranes to create defects sufficient for the passage of the 90 nm diameter capsid across cell membranes. Recent observations suggest that adenovirus type 5 (Ad5) capsid uncoating occurs at the cell surface upon binding to both the coxsackievirus and adenovirus receptor and αv integrins. This uncoating event leads to the exposure of the capsid membrane lytic protein VI. Using the cytosolic protein galectin-3 (gal3) as a marker of membrane rupture, we demonstrate that Ad5 membrane rupture occurs …


Assessing The Effects Of Titanium Dioxide Nanoparticles On Microbial Communities In Stream Sediment Using Artificial Streams And High Throughput Screening, Alexandra Ozaki 2013 Loyola University Chicago

Assessing The Effects Of Titanium Dioxide Nanoparticles On Microbial Communities In Stream Sediment Using Artificial Streams And High Throughput Screening, Alexandra Ozaki

Master's Theses

Nano-titanium dioxide (nano-TiO2) is an engineered nanomaterial used in a wide array of commercial products. The production and use of large amounts of nano-TiO2 is resulting in the unintended release to the environment. Nano-TiO2 is known to be cytotoxic due primarily to its ability to generate reactive oxygen species, and negative impacts on a variety of organisms have been demonstrated, but the effects of nano-TiO2 on complex microbial communities under ecologically relevant conditions have rarely been tested. We conducted a controlled manipulative experiment using recirculating model streams dosed with a one-time amendment of 1mg L-1 nano-TiO2 (specifically P25). Within one …


Hypoxia Inducible Factor 1 Alpha (Hif-1a): A Major Regulator Of Placental Development, Renee E. Albers 2013 Wright State University - Main Campus

Hypoxia Inducible Factor 1 Alpha (Hif-1a): A Major Regulator Of Placental Development, Renee E. Albers

Browse all Theses and Dissertations

Hypoxia-inducible factor-1 alpha (HIF-1a) is a critical component of the cellular oxygen-sensing machinery and is essential for placental formation and embryonic survival. In this study, we promoted prolonged expression of HIF-1a, by using a form that is insensitive to oxygen, denoted as CA-HIF-1a. In order to have continual placental specific expression of the CA-HIF-1a, lentiviral infection was performed on embryos at the blastocyst stage of development and transferred into pseudo-pregnant mothers. Placental analysis was performed via in situ hybridization on embryonic day 14.5 (E14.5) to determine the effects of CA-HIF-1a prolonged expression. Data indicate that prolonged activity of CA-HIF-1a restricted …


Antilisterial Characteristics Of Volatile Essential Oils, Leeann L. Slaughter 2013 University of Kentucky

Antilisterial Characteristics Of Volatile Essential Oils, Leeann L. Slaughter

Theses and Dissertations--Animal and Food Sciences

This study explored the in vitro and in situ antilisterial inhibitory activity of 16 essential oils during indirect exposure: Spanish Basil oil (Ocimum basilicum), Bay oil (Pimenta racemosa), Italian Bergamot oil (Citrus bergamia), Roman Chamomile oil (Anthemis nobilis), Sir Lanka Cinnamon oil (Cinnamomum zeylanicum), Citral, Clove Bud oil (Syzygium aromaticum), Cumin Seed oil (cuminum cyminum), Eucalyptus oil (Eucalyptus globulus), Eugenol, Geranium extract (Pelargonium graveolens), Marjoram oil (Origanum majorana), Neroli extract (Citrus aurantium), Peppermint oil (Mentha piperita L.), …


The Relative Contribution Of Methanotrophs To Microbial Communities And Carbon Cycling In Soil Overlying A Coal-Bed Methane Seep, Christopher T. Mills, Gregpry F. Slater, Robert F. Dias, Stephanie A. Carr, Christopher M. Reddy, Raleigh Schmidt, Kevin W. Mandernack 2013 Old Dominion University

The Relative Contribution Of Methanotrophs To Microbial Communities And Carbon Cycling In Soil Overlying A Coal-Bed Methane Seep, Christopher T. Mills, Gregpry F. Slater, Robert F. Dias, Stephanie A. Carr, Christopher M. Reddy, Raleigh Schmidt, Kevin W. Mandernack

Chemistry & Biochemistry Faculty Publications

Seepage of coal-bed methane (CBM) through soils is a potential source of atmospheric CH4 and also a likely source of ancient (i.e. 14C-dead) carbon to soil microbial communities. Natural abundance 13C and 14C compositions of bacterial membrane phospholipid fatty acids (PLFAs) and soil gas CO2 and CH4 were used to assess the incorporation of CBM-derived carbon into methanotrophs and other members of the soil microbial community. Concentrations of type I and type II methanotroph PLFA biomarkers (16:1ω8c and 18:1ω8c, respectively) were elevated in CBM-impacted soils compared with a control site. Comparison …


Expression Of An Epitope Tagged Tarp Effector In Chlamydia Trachomatis, Brenda Nguyen 2013 University of Central Florida

Expression Of An Epitope Tagged Tarp Effector In Chlamydia Trachomatis, Brenda Nguyen

HIM 1990-2015

Previous studies performed on Chlamydia trachomatis have demonstrated how these obligate intracellular microbes invade host cells through the utilization of secreted effector proteins. One secreted effector called Tarp (translocated actin recruiting protein) is implicated in cytoskeleton rearrangements that promote bacterial entry into the host cell. The focus of our study is to create a plasmid that carries the tarP gene that when transcribed and translated from within Chlamydia trachomatis will generate a c-Myc epitope tagged Tarp. The tag will be used in future studies to track the progression of the protein through the infectious process and will allow us to …


Development Of An Alkaline Phosphatase Reporter System For Use In The Lyme Disease Spirochete Borrelia Burgdorferi, Selina Sutchu 2013 University of Central Florida

Development Of An Alkaline Phosphatase Reporter System For Use In The Lyme Disease Spirochete Borrelia Burgdorferi, Selina Sutchu

HIM 1990-2015

The use of the periplasmic alkaline phosphatase (PhoA) reporter protein from E. coli has been critical for definition of the topology of transmembrane proteins of multiple bacterial species. This report demonstrates development of a PhoA reporter system in B. burgdorferi. Codon usage of the E. coli phoA in B. burgdorferi was analyzed and an optimized version of the gene was obtained. In order to assess the differential activity of the reporter system, two optimized PhoA-fusion construct using B. burgdorferi proteins were engineered: one using the periplasmic protein OppAIV and one using the cytoplasmic protein PncA. The activity of PhoA requires …


Understanding The Role Of Plasmodium Falciparum Vamp8 Snare Homologue, Katherine Ferreira 2013 University of Central Florida

Understanding The Role Of Plasmodium Falciparum Vamp8 Snare Homologue, Katherine Ferreira

HIM 1990-2015

Malaria is one of the worlds most deadly infectious diseases and results in almost a million deaths each year, largely in children under the age of five in Sub-Saharan Africa. Outside Africa, malaria is responsible for a large number of cases in the Amazon rainforest of Brazil, Middle East, and in some areas of Asia [37]. According to the World Health Organization, there was an estimated 655, 000 deaths from malaria in 2012. Malaria is caused by a eukaryotic Apicomplexan parasite, Plasmodium, which has three distinct life cycles occurring in the midgut of the female Anopheles mosquito, the liver of …


Equine Serum Antibody Responses To Streptococcus Equi And Streptococcus Zooepidemicus, Rafaela De Negri 2013 University of Kentucky

Equine Serum Antibody Responses To Streptococcus Equi And Streptococcus Zooepidemicus, Rafaela De Negri

Theses and Dissertations--Veterinary Science

Streptococcus zooepidemicus (Sz) and Streptococcus equi (Se) share 98% DNA sequence homology, but display different pathogenic properties. Infection by one organism does not cross-protect against the other. To better understand pathogenic differences between these organisms and gain information about which proteins are expressed in horses infected experimentally with Se, intrauterine Sz or naturally with respiratory Sz we compared antibody specificities of convalescent sera using ELISA. These comparisons were based on sets of 8 and 14 immunoreactive recombinant proteins of Se strain CF32 and Sz strain NC78, respectively. Sera from donkeys that were previously naturally affected with strangles and later developed …


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