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Association Between Chronic Liver And Colon Inflammation During The Development Of Murine Syngeneic Graft-Versus-Host Disease, Jason Anthony Brandon, Jacqueline Perez-Rodriguez, C. Darrell Jennings, Donald A. Cohen, Vishal J. Sindhava, Subbarao Bondada, Alan M. Kaplan, J. Scott Bryson 2010 University of Kentucky

Association Between Chronic Liver And Colon Inflammation During The Development Of Murine Syngeneic Graft-Versus-Host Disease, Jason Anthony Brandon, Jacqueline Perez-Rodriguez, C. Darrell Jennings, Donald A. Cohen, Vishal J. Sindhava, Subbarao Bondada, Alan M. Kaplan, J. Scott Bryson

Microbiology, Immunology, and Molecular Genetics Faculty Publications

The murine model of cyclosporine A (CsA)-induced syngeneic graft-versus-host disease (SGVHD) is a bone marrow (BM) transplantation model that develops chronic colon inflammation identical to other murine models of CD4+ T cell-mediated colitis. Interestingly, SGVHD animals develop chronic liver lesions that are similar to the early peribiliary inflammatory stages of clinical chronic liver disease, which is frequently associated with inflammatory bowel disease (IBD). Therefore, studies were initiated to investigate the chronic liver inflammation that develops in the SGVHD model. To induce SGVHD, mice were lethally irradiated, reconstituted with syngeneic BM, and treated with CsA. All of the SGVHD animals …


Bpab, A Novel Protein Encoded By The Lyme Disease Spirochete's Cp32 Prophages, Binds To Erp Operator 2 Dna, Logan H. Burns, Claire A. Adams, Sean P. Riley, Brandon L. Jutras, Amy Bowman, Alicia M. Chenail, Anne E. Cooley, Laura A. Haselhorst, Alisha M. Moore, Kelly Babb, Michael G. Fried, Brian Stevenson 2010 University of Kentucky

Bpab, A Novel Protein Encoded By The Lyme Disease Spirochete's Cp32 Prophages, Binds To Erp Operator 2 Dna, Logan H. Burns, Claire A. Adams, Sean P. Riley, Brandon L. Jutras, Amy Bowman, Alicia M. Chenail, Anne E. Cooley, Laura A. Haselhorst, Alisha M. Moore, Kelly Babb, Michael G. Fried, Brian Stevenson

Microbiology, Immunology, and Molecular Genetics Faculty Publications

Borrelia burgdorferi produces Erp outer surface proteins throughout mammalian infection, but represses their synthesis during colonization of vector ticks. A DNA region 5′ of the start of erp transcription, Operator 2, was previously shown to be essential for regulation of expression. We now report identification and characterization of a novel erp Operator 2-binding protein, which we named BpaB. erp operons are located on episomal cp32 prophages, and a single bacterium may contain as many as 10 different cp32s. Each cp32 family member encodes a unique BpaB protein, yet the three tested cp32-encoded BpaB alleles all bound to the same DNA …


Blood Kinetics Of Four Intraperitoneally Administered Therapeutic Candidate Bacteriophages In Healthy And Neutropenic Mice, Jumpei Uchiyama, Yoshihiro Maeda, Iyo Takemura, Russ Chess-Williams, Hiroshi Wakiguchi, Shigenobu Matsuzaki 2010 Bond University

Blood Kinetics Of Four Intraperitoneally Administered Therapeutic Candidate Bacteriophages In Healthy And Neutropenic Mice, Jumpei Uchiyama, Yoshihiro Maeda, Iyo Takemura, Russ Chess-Williams, Hiroshi Wakiguchi, Shigenobu Matsuzaki

Russ Chess-Williams

Due to multiple-drug resistant bacteria, phage therapy is being revisited. Although most animal experiments focus on therapeutic efficacy, the blood clearance kinetics of phages have not been well described. For further development of an efficient therapeutic strategy, information on phage blood kinetics is important. In this study, time-course concentration changes in peripheral blood of healthy and neutropenic mice were measured using four therapeutic phages (φMR11, KPP10, φEF24C, and KEP10). The results showed a two- to three-day rapid phage clearance, which fits a two-compartment model.


Blood Kinetics Of Four Intraperitoneally Administered Therapeutic Candidate Bacteriophages In Healthy And Neutropenic Mice, Jumpei Uchiyama, Yoshihiro Maeda, Iyo Takemura, Russ Chess-Williams, Hiroshi Wakiguchi, Shigenobu Matsuzaki 2010 Bond University

Blood Kinetics Of Four Intraperitoneally Administered Therapeutic Candidate Bacteriophages In Healthy And Neutropenic Mice, Jumpei Uchiyama, Yoshihiro Maeda, Iyo Takemura, Russ Chess-Williams, Hiroshi Wakiguchi, Shigenobu Matsuzaki

Russ Chess-Williams

Due to multiple-drug resistant bacteria, phage therapy is being revisited. Although most animal experiments focus on therapeutic efficacy, the blood clearance kinetics of phages have not been well described. For further development of an efficient therapeutic strategy, information on phage blood kinetics is important. In this study, time-course concentration changes in peripheral blood of healthy and neutropenic mice were measured using four therapeutic phages (φMR11, KPP10, φEF24C, and KEP10). The results showed a two- to three-day rapid phage clearance, which fits a two-compartment model.


Primary Human Mammary Epithelial Cells Endocytose Hiv-1 And Facilitate Viral Infection Of Cd4+ T Lymphocytes, Stephanie M. Dorosko, Ruth I. Connor 2010 Dartmouth College

Primary Human Mammary Epithelial Cells Endocytose Hiv-1 And Facilitate Viral Infection Of Cd4+ T Lymphocytes, Stephanie M. Dorosko, Ruth I. Connor

Dartmouth Scholarship

The contribution of mammary epithelial cells (MEC) to human immunodeficiency virus type 1 (HIV-1) in breast milk remains largely unknown. While breast milk contains CD4(+) cells throughout the breast-feeding period, it is not known whether MEC directly support HIV-1 infection or facilitate infection of CD4(+) cells in the breast compartment. This study evaluated primary human MEC for direct infection with HIV-1 and for indirect transfer of infection to CD4(+) target cells. Primary human MEC were isolated and assessed for expression of HIV-1 receptors. MEC were exposed to CCR5-, CXCR4- and dual-tropic strains of HIV-1 and evaluated for viral reverse transcription …


Harnessing The Effect Of Adoptively Transferred Tumor-Reactive T Cells On Endogenous (Host-Derived) Antitumor Immunity, Yolanda Nesbeth, Jose R. Conejo-Garcia 2010 Dartmouth College

Harnessing The Effect Of Adoptively Transferred Tumor-Reactive T Cells On Endogenous (Host-Derived) Antitumor Immunity, Yolanda Nesbeth, Jose R. Conejo-Garcia

Dartmouth Scholarship

Adoptive T cell transfer therapy, the ex vivo activation, expansion, and subsequent administration of tumor-reactive T cells, is already the most effective therapy against certain types of cancer. However, recent evidence in animal models and clinical trials suggests that host conditioning interventions tailored for some of the most aggressive and frequent epithelial cancers will be needed to maximize the benefit of this approach. Similarly, the subsets, stage of differentiation, and ex vivo expansion procedure of tumor-reactive T cells to be adoptively transferred influence their in vivo effectiveness and may need to be adapted for different types of cancer and host …


Mononucleosis And Antigen-Driven T Cell Responses Have Different Requirements For Interleukin-2 Signaling In Murine Gammaherpesvirus Infection, Michael Molloy, Weijun Zhang, Edward Usherwood 2010 Dartmouth College

Mononucleosis And Antigen-Driven T Cell Responses Have Different Requirements For Interleukin-2 Signaling In Murine Gammaherpesvirus Infection, Michael Molloy, Weijun Zhang, Edward Usherwood

Dartmouth Scholarship

Interleukin-2 (IL-2) has been implicated as being necessary for the optimal formation of primary CD8+ T cell responses against various pathogens. Here we have examined the role that IL-2 signaling plays in several aspects of a CD8+ T cell response against murine gammaherpesvirus 68 (MHV-68). Exposure to MHV-68 causes a persistent infection, along with infectious mononucleosis, providing a model for studying these processes in mice. Our study indicates that CD25 is necessary for optimal expansion of the antigen-specific CD8+ T cell response but not for the long-term memory response. Contrastingly, IL-2 signaling through CD25 is absolutely required …


Cross-Reactivity Of Antibodies Against Leptospiral Recurrent Uveitis-Associated Proteins A And B (Lrua And Lrub) With Eye Proteins, Ashutosh Verma, Pawan Kumar, Kelly Babb, John F. Timoney, Brian Stevenson 2010 University of Kentucky

Cross-Reactivity Of Antibodies Against Leptospiral Recurrent Uveitis-Associated Proteins A And B (Lrua And Lrub) With Eye Proteins, Ashutosh Verma, Pawan Kumar, Kelly Babb, John F. Timoney, Brian Stevenson

Microbiology, Immunology, and Molecular Genetics Faculty Publications

Infection by Leptospira interrogans has been causally associated with human and equine uveitis. Studies in our laboratories have demonstrated that leptospiral lipoprotein LruA and LruB are expressed in the eyes of uveitic horses, and that antibodies directed against LruA and LruB react with equine lenticular and retinal extracts, respectively. These reactivities were investigated further by performing immunofluorescent assays on lenticular and retinal tissue sections. Incubation of lens tissue sections with LruA-antiserum and retinal sections with LruB-antiserum resulted in positive fluorescence. By employing two-dimensional gel analyses followed by immunoblotting and mass spectrometry, lens proteins cross-reacting with LruA antiserum were identified to …


Identification Of The Causative Bacteria In Musculoskeletal Infections Using 16s Rdna - Denaturing Gradient Gel Electrophoresis Analysis, Karen Gomez 2010 University Of Texas Graduate School of Biomedical Sciences at Houston

Identification Of The Causative Bacteria In Musculoskeletal Infections Using 16s Rdna - Denaturing Gradient Gel Electrophoresis Analysis, Karen Gomez

Dissertations & Theses (Open Access)

Musculoskeletal infections are infections of the bone and surrounding tissues. They are currently diagnosed based on culture analysis, which is the gold standard for pathogen identification. However, these clinical laboratory methods are frequently inadequate for the identification of the causative agents, because a large percentage (25-50%) of confirmed musculoskeletal infections are false negatives in which no pathogen is identified in culture. My data supports these results. The goal of this project was to use PCR amplification of a portion of the 16S rRNA gene to test an alternative approach for the identification of these pathogens and to assess the diversity …


Rabies Virus Infection Induces Type I Interferon Production In An Ips-1 Dependent Manner While Dendritic Cell Activation Relies On Ifnar Signaling., Elizabeth J Faul, Celestine N Wanjalla, Mehul S Suthar, Michael Gale, Christoph Wirblich, Matthias J Schnell 2010 Department of Microbiology and Immunology, Jefferson Medical College, Thomas Jefferson University, Philadelphia, PA

Rabies Virus Infection Induces Type I Interferon Production In An Ips-1 Dependent Manner While Dendritic Cell Activation Relies On Ifnar Signaling., Elizabeth J Faul, Celestine N Wanjalla, Mehul S Suthar, Michael Gale, Christoph Wirblich, Matthias J Schnell

Department of Microbiology and Immunology Faculty Papers

As with many viruses, rabies virus (RABV) infection induces type I interferon (IFN) production within the infected host cells. However, RABV has evolved mechanisms by which to inhibit IFN production in order to sustain infection. Here we show that RABV infection of dendritic cells (DC) induces potent type I IFN production and DC activation. Although DCs are infected by RABV, the viral replication is highly suppressed in DCs, rendering the infection non-productive. We exploited this finding in bone marrow derived DCs (BMDC) in order to differentiate which pattern recognition receptor(s) (PRR) is responsible for inducing type I IFN following infection …


The Efficacy And Safety Of Insulin-Sensitizing Drugs In Hiv-Associated Lipodystrophy Syndrome: A Meta-Analysis Of Randomized Trials, Siddharth H. Sheth, Robin J. Larson 2010 Dartmouth College

The Efficacy And Safety Of Insulin-Sensitizing Drugs In Hiv-Associated Lipodystrophy Syndrome: A Meta-Analysis Of Randomized Trials, Siddharth H. Sheth, Robin J. Larson

Dartmouth Scholarship

HIV-associated lipodystrophy syndrome (HALS) is characterized by insulin resistance, abnormal lipid metabolism and redistribution of body fat. To date, there has been no quantitative summary of the effects of insulin sensitizing-agents for the treatment of this challenging problem. We searched MEDLINE, the Cochrane Library, clinical trial registries, conference proceedings and references for randomized trials evaluating rosiglitazone, pioglitazone or metformin in patients with evidence of HALS (last update December 2009). Two reviewers independently abstracted data and assessed quality using a standard form. We contacted authors for missing data and calculated weighted mean differences (WMD) and 95% confidence intervals (CI) for each …


The Lysr-Type Virulence Activator Aphb Regulates The Expression Of Genes In Vibrio Cholerae In Response To Low Ph And Anaerobiosis, Gabriela Kovacikova, Wei Lin, Karen Skorupski 2010 Dartmouth College

The Lysr-Type Virulence Activator Aphb Regulates The Expression Of Genes In Vibrio Cholerae In Response To Low Ph And Anaerobiosis, Gabriela Kovacikova, Wei Lin, Karen Skorupski

Dartmouth Scholarship

AphB is a LysR-type activator that initiates the expression of the virulence cascade in Vibrio cholerae by cooperating with the quorum-sensing-regulated activator AphA at the tcpPH promoter on the Vibrio pathogenicity island (VPI). To identify the ancestral chromosomal genes in V. cholerae regulated by AphB, we carried out a microarray analysis and show here that AphB influences the expression of a number of genes that are not associated with the VPI. One gene strongly activated by AphB is cadC, which encodes the ToxR-like transcriptional activator responsible for activating the expression of lysine decarboxylase, which plays an important role in …


Role Of Pknb Kinase In Antibiotic Resistance And Virulence In Community-Acquired Methicillin-Resistant Staphylococcus Aureus Strain Usa300, S. Tamber, J. Schwartzman, A. L. Cheung 2010 Dartmouth College

Role Of Pknb Kinase In Antibiotic Resistance And Virulence In Community-Acquired Methicillin-Resistant Staphylococcus Aureus Strain Usa300, S. Tamber, J. Schwartzman, A. L. Cheung

Dartmouth Scholarship

The regulation of cellular processes by eukaryote-like serine/threonine kinases is widespread in bacteria. In the last 2 years, several studies have examined the role of serine/threonine kinases in Staphylococcus aureus on cell wall metabolism, autolysis, and virulence, mostly in S. aureus laboratory isolates in the 8325-4 lineage. In this study, we showed that the pknB gene (also called stk1) of methicillin-resistant S. aureus (MRSA) strain COL and the community-acquired MRSA (CA-MRSA) strain USA300 is involved in cell wall metabolism, with the pknB mutant exhibiting enhanced sensitivity to β-lactam antibiotics but not to other classes of antibiotics, including aminoglycosides, ciprofloxacin, …


Epistatic Relationships Between Sara And Agr In Staphylococcus Aureus Biofilm Formation., Karen E. Beenken, Lara N. Mrak, Linda M. Griffin, Agnieszka K. Zielinska, Lindsey N. Shaw, Kelly C. Rice, Alexander R. Horswill, Kenneth W. Bayles, Mark S. Smeltzer 2010 University of Arkansas for Medical Sciences

Epistatic Relationships Between Sara And Agr In Staphylococcus Aureus Biofilm Formation., Karen E. Beenken, Lara N. Mrak, Linda M. Griffin, Agnieszka K. Zielinska, Lindsey N. Shaw, Kelly C. Rice, Alexander R. Horswill, Kenneth W. Bayles, Mark S. Smeltzer

Journal Articles: Pathology and Microbiology

BACKGROUND: The accessory gene regulator (agr) and staphylococcal accessory regulator (sarA) play opposing roles in Staphylococcus aureus biofilm formation. There is mounting evidence to suggest that these opposing roles are therapeutically relevant in that mutation of agr results in increased biofilm formation and decreased antibiotic susceptibility while mutation of sarA has the opposite effect. To the extent that induction of agr or inhibition of sarA could potentially be used to limit biofilm formation, this makes it important to understand the epistatic relationships between these two loci.

METHODOLOGY/PRINCIPAL FINDINGS: We generated isogenic sarA and agr mutants in clinical isolates of S. …


Role Of Flgt In Anchoring The Flagellum Of Vibrio Cholerae, Raquel M. Martinez, Brooke A. Jude, Thomas J. Kirn, Karen Skorupski, Ronald k. Taylor 2010 Dartmouth College

Role Of Flgt In Anchoring The Flagellum Of Vibrio Cholerae, Raquel M. Martinez, Brooke A. Jude, Thomas J. Kirn, Karen Skorupski, Ronald K. Taylor

Dartmouth Scholarship

Flagellar motility has long been regarded as an important virulence factor. In Vibrio cholerae, the single polar flagellum is essential for motility as well as for proper attachment and colonization. In this study, we demonstrate that the novel flagellar protein FlgT is involved in anchoring the flagellum to the V. cholerae cell. A screen for novel colonization factors by use of TnphoA mutagenesis identified flgT. An in-frame deletion of flgT established that FlgT is required for attachment, colonization, and motility. Transmission electron microscopy revealed that while the flgT mutant is capable of assembling a phenotypically normal flagellum, …


Efficient Activation Of Reconstructed Rat Embryos By Cyclin-Dependent Kinase Inhibitors, Robin L. Webb, Kirk A. Findlay, Michael A. Green, Tina L. Beckett, M. Paul Murphy 2010 University of Kentucky

Efficient Activation Of Reconstructed Rat Embryos By Cyclin-Dependent Kinase Inhibitors, Robin L. Webb, Kirk A. Findlay, Michael A. Green, Tina L. Beckett, M. Paul Murphy

Molecular and Cellular Biochemistry Faculty Publications

Background

Over the last decade a number of species, from farm animals to rodents, have been cloned using somatic cell nuclear transfer technology (SCNT). This technique has the potential to revolutionize the way that genetically modified animals are made. In its current state, the process of SCNT is very inefficient (<5% success rate), with several technical and biological hurdles hindering development. Yet, SCNT provides investigators with powerful advantages over other approaches, such as allowing for prescreening for the desired level of transgene expression and eliminating the excess production of undesirable wild-type animals. The rat plays a significant role in biomedical research, but SCNT has been problematic for this species. In this study, we address one aspect of the problem by evaluating methods of activation in artificially constructed rat embryos.

Principal Findings

We demonstrate that treatment with a calcium ionophore (ionomycin) combined with a variety of cyclin-dependent kinase inhibitors is an effective way to activate rat embryos. This is in contrast to methods developed for the mouse embryo, which tolerates much less specific chemical treatments. Methods developed to activate …


Antimicrobial And Antioxidant Activities Of Essential Oil And Methanol Extract Of Jasminum Sambac From Djibouti, Fatou Abdoul-Latif, Prosper Edou, François Eba, Nabil Mohamed, Adwa Ali, Samatar Djama, Louis-Clément Obame, Mamoudou Hama DICKO 2010 University of Djibouti

Antimicrobial And Antioxidant Activities Of Essential Oil And Methanol Extract Of Jasminum Sambac From Djibouti, Fatou Abdoul-Latif, Prosper Edou, François Eba, Nabil Mohamed, Adwa Ali, Samatar Djama, Louis-Clément Obame, Mamoudou Hama Dicko

Pr. Mamoudou H. DICKO, PhD

The essential oil of jasminum sambac from Djibouti was subjected to screening for their possible antioxidant activity by two complementary test systems, namely DPPH free radical scavenging and beta-carotene-linoleic acid assays. Butylated hydroxytoluene (BHT) was used as positive control in both test systems. In the DPPH test system, the IC50 value of essential oil and methanol extract were respectively 7.43 and 2.30 μg/ml. In the beta-carotene-linoleic acid system, oxidation was effectively inhibited by Jasminum sambac, the RAA value of essential oil and methanol extract were respectively 96.6 and 93.9%. When compared to BHT, the essential oil and methanol extract had …


Maternal Consumption Of Canola Oil Suppressed Mammary Gland Tumorigenesis In C3(1) Tag Mice Offspring, Gabriela Ion, Juliana A. Akinsete, W. Elaine Hardman 2010 Marshall University

Maternal Consumption Of Canola Oil Suppressed Mammary Gland Tumorigenesis In C3(1) Tag Mice Offspring, Gabriela Ion, Juliana A. Akinsete, W. Elaine Hardman

Biochemistry and Microbiology

Background: Maternal consumption of a diet high in omega 6 polyunsaturated fats (n-6 PUFA) has been shown to increase risk whereas a diet high in omega 3 polyunsaturated fats (n-3 PUFA) from fish oil has been shown to decrease risk for mammary gland cancer in female offspring of rats. The aim of this study was to determine whether increasing n-3 PUFA and reducing n-6 PUFA by using canola oil instead of corn oil in the maternal diet might reduce the risk for breast cancer in female offspring.

Methods: Female SV 129 mice were divided into two groups and placed on …


Structure Of Vibrio Cholerae Toxt Reveals A Mechanism For Fatty Acid Regulation Of Virulence Genes, Michael J. Lowden, Karen Skorupski, Maria Pellegrini, Michael G. Chiorazzo, Ronald K. Taylor, F. Jon Kull 2010 Dartmouth College

Structure Of Vibrio Cholerae Toxt Reveals A Mechanism For Fatty Acid Regulation Of Virulence Genes, Michael J. Lowden, Karen Skorupski, Maria Pellegrini, Michael G. Chiorazzo, Ronald K. Taylor, F. Jon Kull

Dartmouth Scholarship

Cholera is an acute intestinal infection caused by the bacterium Vibrio cholerae. In order for V. cholerae to cause disease, it must produce two virulence factors, the toxin-coregulated pilus (TCP) and cholera toxin (CT), whose expression is controlled by a transcriptional cascade culminating with the expression of the AraC-family regulator, ToxT. We have solved the 1.9 A resolution crystal structure of ToxT, which reveals folds in the N- and C-terminal domains that share a number of features in common with AraC, MarA, and Rob as well as the unexpected presence of a buried 16-carbon fatty acid, cis-palmitoleate. The finding that …


Proteomic Analysis Of Iron Acquisition, Metabolic And Regulatory Responses Of Yersinia Pestis To Iron Starvation, Rembert Pieper, Shih-Ting Huang, Prashanth P. Parmar, David J. Clark, Hamid Alami, Robert D. Fleischmann, Robert D. Perry, Scott N. Peterson 2010 J. Craig Venter Institute

Proteomic Analysis Of Iron Acquisition, Metabolic And Regulatory Responses Of Yersinia Pestis To Iron Starvation, Rembert Pieper, Shih-Ting Huang, Prashanth P. Parmar, David J. Clark, Hamid Alami, Robert D. Fleischmann, Robert D. Perry, Scott N. Peterson

Microbiology, Immunology, and Molecular Genetics Faculty Publications

BACKGROUND: The Gram-negative bacterium Yersinia pestis is the causative agent of the bubonic plague. Efficient iron acquisition systems are critical to the ability of Y. pestis to infect, spread and grow in mammalian hosts, because iron is sequestered and is considered part of the innate host immune defence against invading pathogens. We used a proteomic approach to determine expression changes of iron uptake systems and intracellular consequences of iron deficiency in the Y. pestis strain KIM6+ at two physiologically relevant temperatures (26°C and 37°C).

RESULTS: Differential protein display was performed for three Y. pestis subcellular fractions. Five characterized Y. pestis …


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