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Changes In Microbial Communities Along Redox Gradients In Polygonized Arctic Wet Tundra Soils, David A. Lipson, Ted K. Raab, Melanie Parker, Scott T. Kelley, Colin J. Brislawn, Janet Jansson 2015 San Diego State University

Changes In Microbial Communities Along Redox Gradients In Polygonized Arctic Wet Tundra Soils, David A. Lipson, Ted K. Raab, Melanie Parker, Scott T. Kelley, Colin J. Brislawn, Janet Jansson

Ted K. Raab

This study investigated how microbial community structure and diversity varied with depth and topography in ice wedge polygons of wet tundra of the Arctic Coastal Plain in northern Alaska, and what soil variables explain these patterns. We observed strong changes in community structure and diversity with depth, and more subtle changes between areas of high and low topography, with the largest differences apparent near the soil surface. These patterns are most strongly correlated with redox gradients (measured using the ratio of reduced Fe to total Fe in acid extracts as a proxy): conditions grew more reducing with depth and were ...


The Biological Consequences Of Kaolin Geophagia, Deloris Alexander, Desire Richardson, Lakisha Odom, Kara Cromwell, DeJuana Grant, Micoya Myers, Eddy Cadet, Hamid Mahama, Vijaya Rangari, Ralphenia Pace, Ramble Ankumah, Kokoasse Kpomblekou-A, Curtis Fluker 2015 Tuskegee University

The Biological Consequences Of Kaolin Geophagia, Deloris Alexander, Desire Richardson, Lakisha Odom, Kara Cromwell, Dejuana Grant, Micoya Myers, Eddy Cadet, Hamid Mahama, Vijaya Rangari, Ralphenia Pace, Ramble Ankumah, Kokoasse Kpomblekou-A, Curtis Fluker

Professional Agricultural Workers Journal

Abstract

Kaolin geophagia is associated with the relief of gastrointestinal distress, but it may also cause adverse health effects on the body. This study was designed to: assess kaolin composition; test if 129SvEv mice would consume kaolin and determine the consequences of consumption; and assess rotational stress modulation of consumption. Thirteen kaolin samples were purchased from Alabama and Georgia stores. Chemical and physical properties were characterized for each sample using a Munsell chart, pH meter, Energy Dispersive Spectroscopy, Transmission Electron Microscopy, Visible Near-InfraRed Spectra, and Inductively Coupled Plasma-Optical Emission Spectrometry. Kaolin was then given to mice as food supplements and ...


Virulence Gene Expression Of Vibrio Parahaemolyticus In The Viable But Nonculturable State, Tiffany Pui-Yun Tse 2015 California Polytechnic State University - San Luis Obispo

Virulence Gene Expression Of Vibrio Parahaemolyticus In The Viable But Nonculturable State, Tiffany Pui-Yun Tse

Master's Theses and Project Reports

Vibrio parahaemolyticus is a food-borne pathogen commonly associated with the consumption of raw or undercooked seafood resulting in primary infections of the human gastrointestinal tract. It is estimated to cause about 4500 illnesses each year in the United States. However, infection from this food-borne pathogen can be avoided if this organism is detected in the implicated food, prior to consumption. Current standard methods of detecting this organism are dependent on the culturability of the bacteria. Detection based on an organism’s culturability may be problematic as V. parahaemolyticus has been known to exist in a viable but nonculturable (VBNC) state ...


Granulocyte Colony-Stimulating Factor: Its Role In Gut-Homing Macrophage Generation And Colitis, And Production By Probiotics, Shahab Meshkibaf 2015 The University of Western Ontario

Granulocyte Colony-Stimulating Factor: Its Role In Gut-Homing Macrophage Generation And Colitis, And Production By Probiotics, Shahab Meshkibaf

University of Western Ontario - Electronic Thesis and Dissertation Repository

The pleiotropic cytokine granulocyte-colony stimulatory factor (G-CSF) is mainly required for the generation of neutrophils, but its role in macrophage generation has also been reported. In addition, G-CSF is effective for the down-regulation of inflammatory cytokines and ameliorating gut disorders, such as colitis. However, the G-CSF function in macrophage generation and gut immunity remains unclear. The first focus of this thesis was to assess the role of G-CSF in macrophage generation and its contribution to gut immunity. G-CSF was found to promote the generation of Gr-1high/F4/80+ macrophages in macrophage (M)-CSF-treated bone marrow cells, most likely through suppressing ...


Generation And Assessment Of Muscular Mutations In Caenorhabditis Elegans, Katie N. Reget 2015 DePaul University

Generation And Assessment Of Muscular Mutations In Caenorhabditis Elegans, Katie N. Reget

DePaul Discoveries

A study of egg laying muscular mutations in C. elegans was conducted over a span of ten weeks. Parent (EGL-19) and wild type (N2) were exposed to mutagenesis and integration mutation techniques to generate genetic and physical different mutants. Overall, four genetic, physical and phenotypically unique worms were generated for the process of mutagenesis. The worms used in the process of integration were found to have shortened life spans, reduced size and decrease numbers of progeny.


Chronic Inflammation As A Result Of Hepatitis C Virus Infection: A Review Of The Literature, Samantha L. Lane 2015 DePaul University

Chronic Inflammation As A Result Of Hepatitis C Virus Infection: A Review Of The Literature, Samantha L. Lane

DePaul Discoveries

Approximately 170 million people are infected with Hepatitis C virus (HCV) worldwide5,6. It is estimated that roughly 80% of those infected suffer from persistent infection with the virus; this persistence of infection is progressive, and over time can lead to fibrosis, cirrhosis, and hepatocellular carcinoma7. Chronic inflammation and apoptotic deregulation are both hallmarks of chronic HCV infection, and many molecular pathways are initiated in both the innate and adaptive immune responses during infection with this viral pathogen. The aim of this review was to survey some of the major molecular mechanisms responsible for the induction of chronic ...


Functional Analysis Of The Molluscum Contagiosum Virus Mc160 Death Effector Domain-Containing Protein Rxdl Motif, Sarah Weber 2015 Seton Hall University

Functional Analysis Of The Molluscum Contagiosum Virus Mc160 Death Effector Domain-Containing Protein Rxdl Motif, Sarah Weber

Seton Hall University Dissertations and Theses (ETDs)

The Molluscum contagiosum virus (MCV) is a member of the Poxviridae family that causes benign skin lesions. MCV lesions persist on average for 8-12 months in otherwise healthy individuals. MCV lesions are characterized by reduced inflammation. The persistence and reduction of inflammation at the site of MCV lesions have been attributed to MCV immune evasion genes. MCV encodes two death effector domain (DED) containing proteins, MC159 and MC160. DEDs are found in cellular proteins such as FADD and procaspase-8. These cellular proteins are involved in several innate immune responses such as apoptosis and activation of interferon (IFN). Presumably, MC159 and ...


The C-Terminal Linker Of Ftsz Acts As An Intrinsically Disordered Peptide During Cell Division In Bacillus Subtilis, Steven Grigsby 2015 Washington University in St Louis

The C-Terminal Linker Of Ftsz Acts As An Intrinsically Disordered Peptide During Cell Division In Bacillus Subtilis, Steven Grigsby

Undergraduate Theses—Unrestricted

The bacterial tubulin homologue FtsZ polymerizes in vitro in a GTP-dependent manner to form long, single stranded filaments. In cells, these filaments assemble at the nascent division site, interacting laterally to form the contractile Z ring. The Z ring serves as a scaffold for the rest of the division machinery and constricts at the leading edge of the invaginating septum during cytokinesis. The FtsZ polypeptide consists of three primary domains: the N-terminal globular core consisting of 315 residues that contains the GTP binding site, a variable and flexible C-terminal linker (CTL) consisting of 50 residues, and a conserved region at ...


Cave Cyanobacteria Showing Antibacterial Activity, Vasiliki Lamprinou, Kyriaki Tryfinopoulou, Emmanuel N. Velonakis, Alkiviadis Vatopoulos, Smaragdi Antonopoulou, Elizabeth Fragopoulou, Adriani Pantazidou, Athena Economou-Amilli 2015 University of Athens, Faculty of Biology, Department of Ecology & Systematics

Cave Cyanobacteria Showing Antibacterial Activity, Vasiliki Lamprinou, Kyriaki Tryfinopoulou, Emmanuel N. Velonakis, Alkiviadis Vatopoulos, Smaragdi Antonopoulou, Elizabeth Fragopoulou, Adriani Pantazidou, Athena Economou-Amilli

International Journal of Speleology

Cave Cyanobacteria - thriving in an ‘extreme’ environment with interesting species biodiversity - are supposed to be a potential source of bioactive compounds. Lipid extracts from pure cultures of two recently established Cyanobacteria from Greek caves, Toxopsis calypsus and Phormidium melanochroun, were used for antibacterial screening against human pathogenic bacteria (reference and clinical isolates). Antimicrobial Susceptibility testing for both taxa was carried out using the disc-diffusion (Kirby Bauer) method, while preliminary data applying the standard broth microdilution method for the determination of the Minimal Inhibitory Concentration (MIC) are given only for T. calypsus. Antibacterial activity was demonstrated against the Gram-positive clinical and ...


Human And Murine Clonal Cd8+ T Cell Expansions Arise During Tuberculosis Because Of Tcr Selection, Claudio Nunes-Alves, Matthew G. Booty, Stephen M. Carpenter, Alissa C. Rothchild, Constance J. Martin, Danielle Desjardins, Katherine Steblenko, Henrik N. Kløverpris, Rajhmun Madansein, Duran Ramsuran, Alasdair Leslie, Margarida Correia-Neves, Samuel M. Behar 2015 University of Massachusetts Medical School Worcester

Human And Murine Clonal Cd8+ T Cell Expansions Arise During Tuberculosis Because Of Tcr Selection, Claudio Nunes-Alves, Matthew G. Booty, Stephen M. Carpenter, Alissa C. Rothchild, Constance J. Martin, Danielle Desjardins, Katherine Steblenko, Henrik N. Kløverpris, Rajhmun Madansein, Duran Ramsuran, Alasdair Leslie, Margarida Correia-Neves, Samuel M. Behar

Microbiology and Physiological Systems Publications and Presentations

The immune system can recognize virtually any antigen, yet T cell responses against several pathogens, including Mycobacterium tuberculosis, are restricted to a limited number of immunodominant epitopes. The host factors that affect immunodominance are incompletely understood. Whether immunodominant epitopes elicit protective CD8+ T cell responses or instead act as decoys to subvert immunity and allow pathogens to establish chronic infection is unknown. Here we show that anatomically distinct human granulomas contain clonally expanded CD8+ T cells with overlapping T cell receptor (TCR) repertoires. Similarly, the murine CD8+ T cell response against M. tuberculosis is dominated by TB10.44-11-specific T cells ...


Effect Of Cmvil-10 On Exosome Production By Human Breast Cancer Cells, Susanna N. Basappa 2015 University of San Francisco

Effect Of Cmvil-10 On Exosome Production By Human Breast Cancer Cells, Susanna N. Basappa

Undergraduate Honors Theses

Human cytomegalovirus (HCMV) is a ubiquitous virus that infects 70-90% of the general population, primarily the immunocompromised, but has been implicated in several forms of cancer, including breast cancer. Breast cancer is the second leading cause of cancer related deaths in women in North America, usually from metastasis. Exosomes are 30-100nm vesicles produced by most cells which carry protein and RNA to cells in their microenvironment. The aim of this study is to investigate the impact of HCMV-infection of a secreted viral cytokine, cmvIL-10, on exosome production by highly metastatic breast cancer cells.

MDA-MB-231 cells were cultured in vitro, and ...


Characterization And Fluorescence Of Yellow Biofilms In Karst Caves, Southwest Slovenia, Janez Mulec, Andreea Oarga-Mulec, Rok Tomazin, Tadeja Matos 2015 Karst Research Institute, Research Centre of the Slovenian Academy of Sciences and Arts

Characterization And Fluorescence Of Yellow Biofilms In Karst Caves, Southwest Slovenia, Janez Mulec, Andreea Oarga-Mulec, Rok Tomazin, Tadeja Matos

International Journal of Speleology

Biofilms of different colours that colonize surfaces within karst caves represent a source of nutrients. They occur commonly and abundantly at sites with sediments, and close to seepages or underground rivers. Golden-yellow subaerial biofilms are particularly well observed because of their contrast with their surroundings, the characteristics of the pigment and recently, even more, due to the characteristics of light-emitting diode (LED) illumination. Yellow microbial biofilms were sampled from three caves in southwestern Slovenia, Dimnice, Križna jama and Sveta jama. The highest concentration of cultivable microbes (2.33×108 CFU/g) and the biggest number of identified bacteria (66 ...


Molecular Epidemiology, Genotyping, And Mat Testing Of Toxoplasma Gondii, Jack Kang 2015 University of Tennessee, Knoxville

Molecular Epidemiology, Genotyping, And Mat Testing Of Toxoplasma Gondii, Jack Kang

University of Tennessee Honors Thesis Projects

No abstract provided.


Positive Regulation Of Localization Of Cell Division Proteins In Escherichia Coli, William P. Deaderick 2015 University of Tennessee, Knoxville

Positive Regulation Of Localization Of Cell Division Proteins In Escherichia Coli, William P. Deaderick

University of Tennessee Honors Thesis Projects

No abstract provided.


Characterization And Investigation Of Fungi Inhabiting The Gastrointestinal Tract Of Healthy And Diseased Humans, Mallory J. Suhr 2015 University of Nebraska-Lincoln

Characterization And Investigation Of Fungi Inhabiting The Gastrointestinal Tract Of Healthy And Diseased Humans, Mallory J. Suhr

Dissertations & Theses in Food Science and Technology

Gastrointestinal microbiome studies have failed to include fungi in total community analyses. As a result, their diversity and function in the gut is poorly understood. Recent work has begun to uncover the role intestinal fungi play in diet, immune system development, interactions with other microorganisms in the gut, and pathogenesis of diseases. Advances in sequencing technologies allow for the ability to profile the fungal gut microbiome (“mycobiome”) in healthy and diseased states. This thesis explores the mycobiome in 1) healthy humans with a vegetarian diet and 2) pediatric small bowel transplant recipients that develop fungal bloodstream infections.

The gut mycobiome ...


A Two-Component Regulatory System Associated With Scytonemin Biosynthesis In Nostoc Punctiforme Atcc 29133, Jacob P. Janssen 2015 Indiana University - Purdue University Fort Wayne

A Two-Component Regulatory System Associated With Scytonemin Biosynthesis In Nostoc Punctiforme Atcc 29133, Jacob P. Janssen

Masters' Theses

As phototrophic bacteria, cyanobacteria are continually exposed to ultraviolet radiation as they harvest solar energy. In particular, long-wavelength ultraviolet radiation (UVA) damages living cells by releasing reactive oxygen species. To mitigate damage to the cell, some cyanobacteria produce a UVA-absorbing pigment in the extracellular sheath, known as scytonemin. Scytonemin is a heterocyclic, dimeric molecule that is only produced upon induction by UVA. In Nostoc punctiforme ATCC 29133, it is hypothesized that scytonemin is regulated by the two component regulatory system (TCRS) of NpF1277 (sensor kinase) and NpF1278 (response regulator). Gene expression of the TCRS was studied after exposure to UVA ...


Molecular Identification Of Mycobacterium Tuberculosis In The Milwaukee County Institution Grounds Cemetery, Helen Marie Werner 2015 University of Wisconsin-Milwaukee

Molecular Identification Of Mycobacterium Tuberculosis In The Milwaukee County Institution Grounds Cemetery, Helen Marie Werner

Theses and Dissertations

The possibility of identifying Mycobacterium tuberculosis in skeletal remains has been a debated topic for many years. This study utilizes the remains from the 1991 and 1992 excavations of the Milwaukee County Institution Grounds Cemetery, a collection of human skeletons ranging from 1882 to 1925, of various ages and sexes, to address that possibility. To test the utility of previously used methods of osteological identification of tuberculosis, the collection has been analyzed for the IS6110 repetitive element marker using molecular biological techniques, such as Polymerase Chain Reaction (PCR). Eighty-six skeletons from the collection have been analyzed, with nine of them ...


Genetic Diversity, Population Structure, And Evolution Of Virulence In Toxoplasma Gondii, Elliot Keats Cullen Shwab 2015 University of Tennessee - Knoxville

Genetic Diversity, Population Structure, And Evolution Of Virulence In Toxoplasma Gondii, Elliot Keats Cullen Shwab

Doctoral Dissertations

Toxoplasma gondii is among the most widespread eukaryotic pathogens known. It chronically infects approximately one third of the world’s human population and has been isolated from an extremely diverse array of globally distributed mammals and birds. Understanding the structure of the worldwide T. gondii population enhances our understanding of the factors that have shaped that structure and led to the proliferation of one of the most evolutionarily successful pathogens on Earth. Herein we collate genotypic data from global isolates, demonstrating that T. gondii possesses a unique population structure in which only a small number of genotypes dominate throughout the ...


Thermal Inactivation Of Shiga Toxin-Producing Escherichia Coli In Foods, Malcond David Valladares 2015 University of Tennessee - Knoxville

Thermal Inactivation Of Shiga Toxin-Producing Escherichia Coli In Foods, Malcond David Valladares

Doctoral Dissertations

Emerging non-O157 Shiga toxin-producing Escherichia coli (STEC) were recently added to the zero tolerance policy by the USDA-FSIS. Therefore, the precise characterization of their thermal inactivation kinetics in different foods and the effect of stress on thermal inactivation are needed. This research aimed at determining the heat inactivation kinetics of non-O157 and O157 STECs in buffer and model food matrices and the effects of DnaK levels on thermal resistance after acid and heat-shock. Thermal inactivation was carried out in either in 2-ml glass vials or nylon vacuum-sealed bags for buffer and food (spinach, ground-beef, turkey deli-meat, pasta) samples, respectively. Vials ...


Phosphotransacetylase And Xylulose 5-Phosphate/Fructose 6-Phosphate Phosphoketolase: Two Eukaryotic Partners Of Acetate Kinase, Tonya Taylor 2015 Clemson University

Phosphotransacetylase And Xylulose 5-Phosphate/Fructose 6-Phosphate Phosphoketolase: Two Eukaryotic Partners Of Acetate Kinase, Tonya Taylor

All Dissertations

Although acetate is a predominant metabolite produced by many eukaryotic microbes, far less attention has been given to acetate metabolism in eukaryotes than in bacteria and archaea. Acetate kinase (Ack), which catalyzes the reversible phosphorylation of acetate from ATP, is a key enzyme in bacterial acetate metabolism. Ack primarily partners with phosphotransacetylase (Pta), which catalyzes the generation of acetyl phosphate from acetyl-CoA, but can also partner with xylulose 5-phosphate/fructose 6-phosphate phosphoketolase (Xfp), which produces acetyl phosphate from either xylulose 5-phosphate or fructose 6-phosphate. The Ack-Pta pathway, found primarily in bacteria, is also present in lower eukaryotes such as the ...


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