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The Development And Analysis Of A Closed System Of Vitrification For Mammalian Embryos, Jennifer Graves-Herring Dec 2008

The Development And Analysis Of A Closed System Of Vitrification For Mammalian Embryos, Jennifer Graves-Herring

All Dissertations

Embryo cryopreservation is an integral part of assisted reproduction because it allows for future use of these embryos. Cryopreservation occurs when there are supernumerary embryos or when an embryo transfer cannot be performed.
There are two main methods to cryopreserve embryos. The most recent is vitrification, which uses high concentrations of cryoprotectants, a short time to cool and avoids ice crystals. The 'gold standard' is the slow-cool method, which uses low concentrations of cryoprotectants, a long time to cool embryos and produces extracellular ice crystals.
Prior to introducing vitrification as part of the human cryopreservation regime, it is important that …


Characterization Of The Ap-1 And Nf-Kappa B Transcription Factors In The U-87 Mg Astrocytoma Cell Line, Denise L. Smith Dec 2008

Characterization Of The Ap-1 And Nf-Kappa B Transcription Factors In The U-87 Mg Astrocytoma Cell Line, Denise L. Smith

Dissertations

Growth factors, signaling molecules and transcription factors are frequently mutated in cancer and platelet-derived growth factor (PDGF) has been shown to be over-expressed in most gliomas. In the astrocytoma cell line U-87 MG, the over-expression of PDGF has been shown to lead to over-expression of transcription factors activator-protein-1 (AP-1) and nuclear factor-kappa B (NF-κB), and it is believed that the individual subunits of AP-1 (c-Jun, JunB, JunD, c-Fos, FosB, Fra-1, and Fra-2) and NF-κB (c-Rel, p50, p52, p65, and RelB) play different roles in proliferation, survival and differentiation in the U-87 MG cell line.

To assess these different roles, transient …


Intraretinal Signaling By Ganglion Cell Photoreceptors To Dopaminergic Amacrine Neurons, Dao-Qi Zhang, Kwoon Y. Wong, Patricia J. Sollars, David M. Berson, Gary E. Pickard, Douglas G. Mcmahon Sep 2008

Intraretinal Signaling By Ganglion Cell Photoreceptors To Dopaminergic Amacrine Neurons, Dao-Qi Zhang, Kwoon Y. Wong, Patricia J. Sollars, David M. Berson, Gary E. Pickard, Douglas G. Mcmahon

School of Veterinary and Biomedical Sciences: Faculty Publications

Retinal dopaminergic amacrine neurons (DA neurons) play a central role in reconfiguring retinal function according to prevailing illumination conditions, yet the mechanisms by which light regulates their activity are poorly understood. We investigated the means by which sustained light responses are evoked in DA neurons. Sustained light responses were driven by cationic currents and persisted in vitro and in vivo in the presence of L-AP4, a blocker of retinal ON-bipolar cells. Several characteristics of these L-AP4-resistant light responses suggested that they were driven by melanopsin-expressing intrinsically photosensitive retinal ganglion cells (ipRGCs), including long latencies, marked poststimulus persistence, and a peak …


Regulation Of The Bioavailability Of Thioredoxin In The Lens By A Specific Thioredoxin-Binding Protein (Tbp-2), Namal P.M. Liyanage, M. Rohan Fernando, Marjorie F. Lou Aug 2008

Regulation Of The Bioavailability Of Thioredoxin In The Lens By A Specific Thioredoxin-Binding Protein (Tbp-2), Namal P.M. Liyanage, M. Rohan Fernando, Marjorie F. Lou

School of Veterinary and Biomedical Sciences: Faculty Publications

Thioredoxin (TRx) is known to control redox homeostasis in cells. In recent years, a specific TRx binding protein called thioredoxin binding protein-2 (TBP-2) was found in other cell types and it appeared to negatively regulate TRx bioavailability and thereby control TRx biological function. In view of the sensitivity of lens transparency to redox status, proper regulation of TRx bioavailability is of the utmost importance. This study was conducted to examine the presence and function of TBP-2 in human lens epithelial cells (HLE B3). We cloned human lens TBP-2 from a human cDNA library (GenBank accession number AY 594328) and showed …


Biological Signatures Of Vaccine Responses, Lorena Nunez Aug 2008

Biological Signatures Of Vaccine Responses, Lorena Nunez

Honors Scholar Theses

The set of host- and pathogen-specific molecular features of a disease comprise its “signature”. We hypothesize that biological signatures enables distinctions between vaccinated vs. infected individuals. In our research, using porcine samples, protocols were developed that could also be used to identify biological signatures of human disease. Different classes of molecular features will be tested during this project, including indicators of basic immune capacity, which are being studied at this instance.

These indicators of basic immune response such as porcine cytokines and antibodies were validated using Enzyme-linked immunosorbent assay (ELISA). This is an established method that detects antigens by their …


Characterization Of Phosphatidylinositol (3,4,5)-Trisphosphate Subcellular Localization During Endocytosis In Entamoeba Histolytica, Yevgeniya Byekova Jul 2008

Characterization Of Phosphatidylinositol (3,4,5)-Trisphosphate Subcellular Localization During Endocytosis In Entamoeba Histolytica, Yevgeniya Byekova

All Theses

Entamoeba histolytica is a protozoan parasite that causes amoebic dysentery and liver abscess. Currently, the World Health Organization estimates that amoebic dysentery results in 40,000-100,000 deaths annually worldwide, which places amoebiasis second only to malaria as a leading cause of death due to parasitic infection. The pathogenesis of invasive amoebiasis depends on the parasite's ability to carry out endocytosis in the host's bowel lumen enabling it to colonize the digestive tract. The pathogen is contracted by the ingestion of its multinucleate cysts. Upon excystation in the small intestine, motile trophozoites are released into the bowel lumen, where bacteria, erythrocytes, and …


Expression Analysis Of Plant Defense Responses During The Establishment Of Biotrophy And Role Of Abiotic Stress In The Infection Of Dyer’S Woad (Isatis Tinctoria) By Puccinia Thlaspeos, Elizabeth Thomas May 2008

Expression Analysis Of Plant Defense Responses During The Establishment Of Biotrophy And Role Of Abiotic Stress In The Infection Of Dyer’S Woad (Isatis Tinctoria) By Puccinia Thlaspeos, Elizabeth Thomas

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The kinetics and amplitude of the salicylic acid-responsive pathogenesis-related (PR) genes and the cytochrome P450 gene ItCYP79B2 in the compatible interaction between Puccinia thlaspeos and dyer’s woad (Isatis tinctoria) during the first 72 hours of inoculation were examined. Immediately following penetration of the host by the rust pathogen, there was a modest up-regulation of PR genes but a significant down-regulation of ItCYP79B2 expression. During haustoria formation, a significant pathogen-mediated suppression of PR genes was observed with a corresponding up-regulation of ItCYP79B2. This potentially facilitates haustoria formation by P. thlaspeos. After haustoria formation, a more …


A Versatile Assay For The Identification Of Rna Silencing Suppressors Based On Complementation Of Viral Movement, Jason G. Powers, Tim L. Sit, Feng Qu, T. Jack Morris, Kook-Hyung Kim, Steven A. Lommel Jan 2008

A Versatile Assay For The Identification Of Rna Silencing Suppressors Based On Complementation Of Viral Movement, Jason G. Powers, Tim L. Sit, Feng Qu, T. Jack Morris, Kook-Hyung Kim, Steven A. Lommel

Nebraska Center for Virology: Faculty Publications

The cell-to-cell movement of Turnip crinkle virus (TCV) in Nicotiana benthamiana requires the presence of its coat protein (CP), a known suppressor of RNA silencing. RNA transcripts of a TCV construct containing a reporter gene (green fluorescent protein) (TCV-sGFP) in place of the CP open reading frame generated foci of three to five cells. TCV CP delivered in trans by Agrobacterium tumefaciens infiltration potentiated movement of TCV-sGFP and increased foci diameter, on average, by a factor of four. Deletion of the TCV movement proteins in TCV-sGFP (construct TCVΔ92-sGFP) abolished the movement complementation ability of TCV CP. Other known suppressors of …


Development Of An Immunofluorescence Assay Using Recombinant Proteins Expressed In Insect Cells To Screen And Confirm Presence Of Human Herpesvirus 8-Specific Antibodies, Veenu Minhas, Lynsey N. Crosby, Kay L. Crabtree, Saul Phiri, Tendai J. M'Soka, Chipepo Kankasa, William J. Harrington, Charles D. Mitchell, Charles Wood Jan 2008

Development Of An Immunofluorescence Assay Using Recombinant Proteins Expressed In Insect Cells To Screen And Confirm Presence Of Human Herpesvirus 8-Specific Antibodies, Veenu Minhas, Lynsey N. Crosby, Kay L. Crabtree, Saul Phiri, Tendai J. M'Soka, Chipepo Kankasa, William J. Harrington, Charles D. Mitchell, Charles Wood

Nebraska Center for Virology: Faculty Publications

Human herpesvirus 8 (HHV-8), or Kaposi’s sarcoma (KS)-associated herpesvirus, has been linked to all forms of KS. The results of most current serological assays for the detection of HHV-8-specific antibodies have low levels of concordance among themselves. To establish a sensitive and specific testing strategy that can be used to screen for HHV-8-specific antibodies, three HHV-8 proteins, ORF65, ORF73, and K8.1A, were expressed by using baculoviral vectors in insect cells and incorporated into a monoclonal antibodyenhanced immunofluorescence assay (mIFA) termed the Sf9 three-antigen mIFA. The results obtained by this mIFA were compared to those obtained by a standard mIFA with …


Small-Molecule Cd4 Mimics Interact With A Highly Conserved Pocket On Hiv-1 Gp120, Navid Madani, Arne Schön, Amy M. Princiotto, Judith M. Lalonde, Joel R. Cpurter, Takahiro Soeta, Danny Ng, Liping Wang, Evan T. Brower, Shi-Hua Xiang, Young Do Kwon, Chih-Chin Huang, Richard Wyatt, Peter D. Kwong, Ernesto Freire, Amos B. Smith Iii, Joseph Sodroski Jan 2008

Small-Molecule Cd4 Mimics Interact With A Highly Conserved Pocket On Hiv-1 Gp120, Navid Madani, Arne Schön, Amy M. Princiotto, Judith M. Lalonde, Joel R. Cpurter, Takahiro Soeta, Danny Ng, Liping Wang, Evan T. Brower, Shi-Hua Xiang, Young Do Kwon, Chih-Chin Huang, Richard Wyatt, Peter D. Kwong, Ernesto Freire, Amos B. Smith Iii, Joseph Sodroski

Nebraska Center for Virology: Faculty Publications

Human immunodeficiency virus (HIV-1) interaction with the primary receptor, CD4, induces conformational changes in the viral envelope glycoproteins that allow binding to the CCR5 second receptor and virus entry into the host cell. The small molecule NBD-556 mimics CD4 by binding the gp120 exterior envelope glycoprotein, moderately inhibiting virus entry into CD4-expressing target cells, and enhancing CCR5 binding and virus entry into CCR5-expressing cells lacking CD4. Studies of NBD-556 analogues and gp120 mutants suggest that: 1) NBD-556 binds within the Phe 43 cavity, a highly conserved, functionally important pocket formed as gp120 assumes the CD4- bound conformation; 2) the NBD-556 …


The Human Immunodeficiency Virus Type 1 Envelope Confers Higher Rates Of Replicative Fitness To Perinatally Transmitted Viruses Than To Nontransmitted Viruses, Xiaohong Kong, John T. West, Hong Zhang, Danielle M. Shea, Tendai J. M’Soka, Charles Wood Jan 2008

The Human Immunodeficiency Virus Type 1 Envelope Confers Higher Rates Of Replicative Fitness To Perinatally Transmitted Viruses Than To Nontransmitted Viruses, Xiaohong Kong, John T. West, Hong Zhang, Danielle M. Shea, Tendai J. M’Soka, Charles Wood

Nebraska Center for Virology: Faculty Publications

Selection of a minor viral genotype during perinatal transmission of human Immunodeficiency virus type 1

(HIV-1) has been observed, but there is a lack of information on the correlation of the restrictive transmission

with biological properties of the virus, such as replicative fitness. Recombinant viruses expressing the enhanced

green fluorescent protein or the Discosoma sp. red fluorescent (DsRed2) protein carrying the V1 to V5

regions of env from seven mother-infant pairs (MIPs) infected by subtype C HIV-1 were constructed, and

competition assays were carried out to compare the fitness between the transmitted and nontransmitted

viruses. Flow cytometry was used to …


Varying Efficiency Of Long-Term Replication Of Papillomaviruses In Saccharomyces Cerevisiae, Adam J. Rogers, Malte Loggen, Karen Lee, Peter C. Angeletti Jan 2008

Varying Efficiency Of Long-Term Replication Of Papillomaviruses In Saccharomyces Cerevisiae, Adam J. Rogers, Malte Loggen, Karen Lee, Peter C. Angeletti

Nebraska Center for Virology: Faculty Publications

Human papillomaviruses (HPVs) replicate in mitotically active basal keratinocytes. Two virally encoded proteins, E1, a helicase, and E2, a transcription factor, are important players in replication and maintenance of HPV episomes. We previously showed that HPV16 could replicate stably in Saccharomyces cerevisiae [Angeletti, P.C., Kim, K., Fernandes, F.J., and Lambert, P.F. (2002)] and we identified cis-elements that mediate replication and maintenance [J. Virol. 76(7), 3350-3358.; Kim, K., Angeletti, P.C., Hassebroek, E.C., and Lambert, P.F. (2005)]. Here, we demonstrate that although multiple HPV genomes replicate stably in yeast, they do so with differing long-term efficiency; HPV6-Ura3 is replicated at the …


Effects Of Shielding Adenoviral Vectors With Polyethylene Glycol On Vector-Specific And Vaccine-Mediated Immune Responses, Eric A. Weaver, Michael A. Barry Jan 2008

Effects Of Shielding Adenoviral Vectors With Polyethylene Glycol On Vector-Specific And Vaccine-Mediated Immune Responses, Eric A. Weaver, Michael A. Barry

Nebraska Center for Virology: Faculty Publications

Many individuals have been previously exposed to human adenovirus serotype 5 (Ad5). This prior immunity has long been known to hinder its use for gene therapy and as a gene-based vaccine. Given these immunogenicity problems, we have tested whether polyethylene glycol (PEG) can blunt immune effects against Ad5 during systemic and mucosal vaccination. Ad5 vectors were covalently modified with 5-, 20-, and 35-kDa linear PEG polymers and evaluated for their ability to produce immune responses against transgene antigen prod- ucts and the vector itself. We show that shielding Ad5 with different-sized PEGs generally reduces transduction and primary antibody responses by …


The Effects Of Oxidative Stress And Age On Human Spermatozoa, Taryn Mcandrew Jan 2008

The Effects Of Oxidative Stress And Age On Human Spermatozoa, Taryn Mcandrew

Theses : Honours

Male infertility is now recognised as a significant factor in couples having difficulty conceiving. The impact of maternal age has long been known as a limiting factor, however recent research indicates that advancing paternal age can also negatively impact on a couple's chances of conception. One of the major contributing causes of male infertility has now been linked to spermatozoa exposure to reactive oxygen species (ROS). Such exposure induces oxidative stress when coupled with reduced total antioxidant capacity (TAC). Measures of both ROS and TAC are used as tests of oxidative stress status (OSS) which are used together to give …


Oral Immunization Of Rhesus Macaques With Adenoviral Hiv Vaccines Using Enteric-Coated Capsules, George T. Mercier, Pramod N. Nehete, Marco F. Passeri, Bharti N. Nehete, Eric A. Weaver, Nancy Smyth Templeton, Kimberly Schluns, Stephanie S. Buchl, K. Buchl, Michael A. Barry Dec 2007

Oral Immunization Of Rhesus Macaques With Adenoviral Hiv Vaccines Using Enteric-Coated Capsules, George T. Mercier, Pramod N. Nehete, Marco F. Passeri, Bharti N. Nehete, Eric A. Weaver, Nancy Smyth Templeton, Kimberly Schluns, Stephanie S. Buchl, K. Buchl, Michael A. Barry

Nebraska Center for Virology: Faculty Publications

Targeted delivery of vaccine candidates to the gastrointestinal (GI) tract holds potential for mucosal immunization, particularly against mucosal pathogens like the human immunodeficiency virus (HIV). Among the different strategies for achieving targeted release in the GI tract, namely the small intestine, pH sensitive enteric coating polymers have been shown to protect solid oral dosage forms from the harsh digestive environment of the stomach and dissolve relatively rapidly in the small intestine by taking advantage of the luminal pH gradient. We developed an enteric polymethacrylate formulation for coating hydroxy-propyl-methyl-cellulose (HPMC) capsules containing lyophilized Adenoviral type 5 (Ad5) vectors expressing HIV-1 gag …


Thermodynamic Evidence That Ganglioside-Mediated Insertion Of Botulinum A Into The Cholinergic Nerve Ending May Precede Endocytosis And Acidification: A Langmuir Film Study, Bradley Adam Strongin Dec 2007

Thermodynamic Evidence That Ganglioside-Mediated Insertion Of Botulinum A Into The Cholinergic Nerve Ending May Precede Endocytosis And Acidification: A Langmuir Film Study, Bradley Adam Strongin

Theses and Dissertations

Botulinum Neurotoxin (BoNT) is one of the most potent toxins known to human kind. The Atomic Force Microscope (AFM) was employed to investigate the conditions under which BoNT type A heavy chain would bind and/or insert into mica supported dipalmitoylphosphatidylcholine (DPPC) lipid bilayers. As an alternate technique, DPPC/GT1b or total ganglioside extract (80:20) monolayers of a Langmuir Blodgett (LB) Trough were adapted to be artificial membrane models for toxin insertion studies. We conclude that LB monolayer studies are a promising candidate for BoNT/A membrane insertion investigation. Botulinum neurotoxin serotype A insertions into the LB monolayers in the presence of BoNT/A …


Light-Evoked Calcium Responses Of Isolated Melanopsin- Expressing Retinal Ganglion Cells, Andrew T. E. Hartwick, Jayne R. Bramley, Jianing Yu, Kelly T. Stevens, Charles N. Allen, William H. Baldridge, Patricia J. Sollars, Gary E. Pickard Dec 2007

Light-Evoked Calcium Responses Of Isolated Melanopsin- Expressing Retinal Ganglion Cells, Andrew T. E. Hartwick, Jayne R. Bramley, Jianing Yu, Kelly T. Stevens, Charles N. Allen, William H. Baldridge, Patricia J. Sollars, Gary E. Pickard

School of Veterinary and Biomedical Sciences: Faculty Publications

A small number (<2%) of mammalian retinal ganglion cells express the photopigment melanopsin and are intrinsically photosensitive (ipRGCs). Light depolarizes ipRGCs and increases intracellular calcium levels ( [Ca2+]i ) but the signaling cascades underlying these responses have yet to be elucidated. To facilitate physiological studies on these rare photoreceptors, highly enriched ipRGC cultures from neonatal rats were generated using anti-melanopsin-mediated plate adhesion (immunopanning). This novel approach enabled experiments on isolated ipRGCs, eliminating the potential confounding influence of rod/cone-driven input. Light induced a rise in [Ca2+]i (monitored using fura-2 imaging) in the immunopanned ipRGCs and the source of this Ca2+ signal was investigated. The Ca2+ responses were inhibited by 2-aminoethoxydiphenyl borate, SKF-96365 (1–2-(4-methoxyphenyl)-2-[3-(4-methoxyphenyl)propoxy]ethyl-1H-imidazole), flufenamic acid, …


Genome-Wide Transcriptional Profiling Of The Cyclic Amp-Dependent Signaling Pathway During Morphogenic Transitions Of Candida Albicans, Yong-Sun Bahn, Matthew Molenda, Janet F. Staab, Courtney A. Lyman, Laura J. Gordon, Paula Sundstrom Dec 2007

Genome-Wide Transcriptional Profiling Of The Cyclic Amp-Dependent Signaling Pathway During Morphogenic Transitions Of Candida Albicans, Yong-Sun Bahn, Matthew Molenda, Janet F. Staab, Courtney A. Lyman, Laura J. Gordon, Paula Sundstrom

Dartmouth Scholarship

Candida albicans is an opportunistic human fungal pathogen that causes systemic candidiasis as well as superficial mucosal candidiasis. In response to the host environment, C. albicans transitions between yeast and hyphal forms. In particular, hyphal growth is important in facilitating adhesion and invasion of host tissues, concomitant with the expression of various hypha-specific virulence factors. In previous work, we showed that the cyclic AMP (cAMP) signaling pathway plays a crucial role in morphogenic transitions and virulence of C. albicans by studying genes encoding adenylate cyclase-associated protein (CAP1) and high-affinity phosphodiesterase (PDE2) (Y. S. Bahn, J. Staab, and P. Sundstrom, Mol. …


Enhancement Of Efficacy Of Prrsv Vaccines By Altering The Glycosylation Pattern Of Viral Glycoproteins, Asit K. Pattnaik Oct 2007

Enhancement Of Efficacy Of Prrsv Vaccines By Altering The Glycosylation Pattern Of Viral Glycoproteins, Asit K. Pattnaik

School of Veterinary and Biomedical Sciences: Faculty Publications

PRRSV, the causative agent of PRRS is of major economic significance to the pork industry in the USA and around the world. Current commercial vaccine does not provide adequate protection against PRRSV outbreaks. Therefore, there is an urgent need for development of more efficacious vaccine to combat PRRS. Our previous studies have suggested that (i) induction of neutralizing antibody response is an important correlate of evaluating the efficacy of a vaccine; (ii) neutralizing antibodies can be enhanced by hypoglycosylation of the major surface glycoprotein (GP5). While it is known that GP5 plays a prominent role in neutralizing antibody induction, it …


A Group M Consensus Envelope Glycoprotein Induces Antibodies That Neutralize Subsets Of Subtype B And C Hiv-1 Primary Viruses, Hua-Xin Liao, Laura L. Sutherland, Shi-Mao Xia, Mary E. Brock, Richard M. Scearce, Stacie Vanleeuwen, S. Munir Alam, Mildred Mcadams, Eric A. Weaver, Zenaido T. Camacho, Ben-Jiang Ma, Yingying Li, Julie M. Decker, Gary J. Nabel, David C. Montefiori, Beatrice H. Hahn, Bette T. Korber, Feng Gao, Barton F. Haynes Sep 2007

A Group M Consensus Envelope Glycoprotein Induces Antibodies That Neutralize Subsets Of Subtype B And C Hiv-1 Primary Viruses, Hua-Xin Liao, Laura L. Sutherland, Shi-Mao Xia, Mary E. Brock, Richard M. Scearce, Stacie Vanleeuwen, S. Munir Alam, Mildred Mcadams, Eric A. Weaver, Zenaido T. Camacho, Ben-Jiang Ma, Yingying Li, Julie M. Decker, Gary J. Nabel, David C. Montefiori, Beatrice H. Hahn, Bette T. Korber, Feng Gao, Barton F. Haynes

Nebraska Center for Virology: Faculty Publications

HIV-1 subtype C is the most common HIV-1 group M subtype in Africa and many parts of Asia. However, to date HIV-1 vaccine candidate immunogens have not induced potent and broadly neutralizing antibodies against subtype C primary isolates. We have used a centralized gene strategy to address HIV-1 diversity, and generated a group M consensus envelope gene with shortened consensus variable loops (CON-S) for comparative studies with wildtype (WT) Env immunogens. Our results indicate that the consensus HIV-1 group M CON-S Env elicited cross-subtype neutralizing antibodies of similar or greater breadth and titer than the WT Envs tested, indicating the …


Low Molecular Weight Protein Tyrosine Phosphatase (Lmw-Ptp) And Its Possible Physiological Functions Of Redox Signaling In The Eye Lens, Kuiyi Xing, Ashraf Raza, Stefan Lofgren, M. Rohan Fernando, Ye-Shih Ho, Marjorie F. Lou Aug 2007

Low Molecular Weight Protein Tyrosine Phosphatase (Lmw-Ptp) And Its Possible Physiological Functions Of Redox Signaling In The Eye Lens, Kuiyi Xing, Ashraf Raza, Stefan Lofgren, M. Rohan Fernando, Ye-Shih Ho, Marjorie F. Lou

School of Veterinary and Biomedical Sciences: Faculty Publications

Low molecular weight protein tyrosine phosphatase (LMW-PTP) was cloned from human lens epithelial B3 cells (HLE B3) and the recombinant enzyme was purified to homogeneity. The pure enzyme reacted positively with anti-LMW-PTP antibody, displayed tyrosine-specific phosphatase activity and was extremely sensitive to H2O2. The inactivated LMW-PTP could be regenerated by thioltransferase (TTase)/GSH system as demonstrated by both activity assay and by mass spectrometry (MS). The MS study also showed that an intramolecular disulfide bond was formed between C13 and C18 at the active site, and was reduced by the TTase/GSH system. The putative role of LMW-PTP in regulating platelet derived …


Down-Regulation Of Natural Killer Cell Activation In Response To Influenza Virus In Older Adults, Yu Jing Apr 2007

Down-Regulation Of Natural Killer Cell Activation In Response To Influenza Virus In Older Adults, Yu Jing

Theses and Dissertations in Biomedical Sciences

Immune senescence contributes to influenza-associated high mortality and morbidity and reduced vaccine efficacy in elderly people. Type I T cell (Thl)-mediated immunity plays a significant role in Immune responses to influenza infection and vaccination. Natural killer (NK) cells secrete significant amount of IFN-7 , a hallmark Thl cytokine, in response to influenza infection. How aging influences human NK cell IFN-7 production in response to influenza virus has not been well documented. In this study we employed human peripheral blood mononuclear cells (PBMC) and performed intracellular cytokine staining and flow cytometry primarily to investigate how aging influences NK cell activation with …


A 368-Base-Pair Cis-Acting Hwp1 Promoter Region, Hcr, Of Candida Albicans Confers Hypha-Specific Gene Regulation And Binds Architectural Transcription Factors Nhp6 And Gcf1p, Samin Kim, Michael J. Wolyniak, Janet F. Staab, Paula Sundstrom Apr 2007

A 368-Base-Pair Cis-Acting Hwp1 Promoter Region, Hcr, Of Candida Albicans Confers Hypha-Specific Gene Regulation And Binds Architectural Transcription Factors Nhp6 And Gcf1p, Samin Kim, Michael J. Wolyniak, Janet F. Staab, Paula Sundstrom

Dartmouth Scholarship

To elucidate the molecular mechanisms controlling the expression of the hypha-specific adhesin gene HWP1 of Candida albicans, its promoter was dissected and analyzed using a green fluorescent protein reporter gene. A 368-bp region, the HWP1 control region (HCR), was critical for activation under hypha-inducing conditions and conferred developmental regulation to a heterologous ENO1 promoter. A more distal region of the promoter served to amplify the level of promoter activation. Using gel mobility shift assays, a 249-bp subregion of HCR, HCRa, was found to bind at least four proteins from crude extracts of yeasts and hyphae with differing binding patterns dependent …


Ecological Correlates Of Buggy Creek Virus Infection In Oeciacus Vicarius, Southwestern Nebraska, 2004, Amy T. Moore, Eric A. Edwards, Mary Bomberger Brown, Nicholas Komar, Charles R. Brown Jan 2007

Ecological Correlates Of Buggy Creek Virus Infection In Oeciacus Vicarius, Southwestern Nebraska, 2004, Amy T. Moore, Eric A. Edwards, Mary Bomberger Brown, Nicholas Komar, Charles R. Brown

School of Natural Resources: Faculty Publications

Buggy Creek virus (family Togaviridae, genus Alphavirus, BCRV) is an alphavirus within the western equine encephalitis virus complex whose primary vector is the swallow bug, Oeciacus vicarius Horvath (Hemiptera: Cimicidae), an ectoparasite of the colonially nesting cliff swallow, Petrochelidon pyrrhonota, that is also a frequent host for the virus.We investigated ecological correlates of BCRV infection in 100-bug pools at 14 different swallow colony sites in southwestern Nebraska from summer 2004, by using plaque assay on Vero cells to identify cytopathic virus and reverse transcription-polymerase chain reaction to identify noncytopathic viral RNA. We found 26.7% of swallow bug pools …


Arsenic Toxicity In Plhc-1 Cell Line And The Distribution Of Arsenic In Central Appalachia, Yeong Nam Jeong Jan 2007

Arsenic Toxicity In Plhc-1 Cell Line And The Distribution Of Arsenic In Central Appalachia, Yeong Nam Jeong

Theses, Dissertations and Capstones

Our ecosystem has geobiophysical relationships. Environmental pollution can lead to immediate consequences like organism death or lack of reproduction. It can also lead to long-range consequences through mutations and DNA damage. Fish can be affected very directly by environmental contamination in water but the study of fish is not performed well. We are developing a quantitative assay to assess DNA damage in vitro due to heavy metal contamination using a tissue culture line of Poeciliopsis lucida, the desert pupfish, which is used for other toxicology assays. To detect DNA damage, Single Cell Gel Electrophoresis (Comet Assay) is very useful. …


Poxviral B1 Kinase Overcomes Barrier To Autointegration Factor, A Host Defense Against Virus Replication, Matthew S. Wiebe, Paula Traktman Jan 2007

Poxviral B1 Kinase Overcomes Barrier To Autointegration Factor, A Host Defense Against Virus Replication, Matthew S. Wiebe, Paula Traktman

Nebraska Center for Virology: Faculty Publications

Barrier to autointegration factor (BAF) is a DNA-binding protein found in the nucleus and cytoplasm of eukaryotic cells that functions to establish nuclear architecture during mito-sis. Herein, we demonstrate a cytoplasmic role for BAF in host defense during poxviral infections. Vaccinia is the prototypic poxvirus, a family of DNA viruses that replicate ex-clusively in the cytoplasm of infected cells. Mutations in the vaccinia B1 kinase (B1) com-promise viral DNA replication, but the mechanism by which B1 achieves this has remained elusive. We now show that BAF acts as a potent inhibitor of poxvirus replication unless its DNA-binding activity is blocked …


Modulation Of Retroviral Restriction And Proteasome Inhibitor-Resistant Turnover By Changes In The Trim5Α B-Box 2 Domain, Felipe Diaz-Griffero, Alak Kar, Michel Perron, Shi-Hua Xiang, Hassan Javanbakht, Xing Li, Joseph Sodroski Jan 2007

Modulation Of Retroviral Restriction And Proteasome Inhibitor-Resistant Turnover By Changes In The Trim5Α B-Box 2 Domain, Felipe Diaz-Griffero, Alak Kar, Michel Perron, Shi-Hua Xiang, Hassan Javanbakht, Xing Li, Joseph Sodroski

Nebraska Center for Virology: Faculty Publications

An intact B-box 2 domain is essential for the antiretroviral activity of TRIM5α. We modeled the structure of the B-box 2 domain of TRIM5α based on the existing three-dimensional structure of the B-box 2 domain of human TRIM29. Using this model, we altered the residues predicted to be exposed on the surface of this globular structure. Most of the alanine substitutions in these residues exerted little effect on the antiretroviral activity of human TRIM5αhu or rhesus monkey TRIM5αrh. However, alteration of arginine 119 of TRIM5αhu or the corresponding arginine 121 of TRIM5αrh diminished the abilities of …


Functional Interplay Between The B-Box 2 And The B30.2(Spry) Domains Of Trim5Α, Xi Ling, Byeongwoon Song, Shi-Hua Xiang, Joseph Sodroski Jan 2007

Functional Interplay Between The B-Box 2 And The B30.2(Spry) Domains Of Trim5Α, Xi Ling, Byeongwoon Song, Shi-Hua Xiang, Joseph Sodroski

Nebraska Center for Virology: Faculty Publications

The retroviral restriction factors, TRIM5α and TRIMCyp, consist of RING and B-box 2 domains separated by a coiled coil from carboxy-terminal domains. These carboxy-terminal domains (the B30.2(SPRY) domain in TRIM5α and the cyclophilin A domain in TRIMCyp) recognize the retroviral capsid. Here we show that some B-box 2 changes in TRIM5α, but not in TRIMCyp, resulted in decreased human immunodeficiency virus (HIV-1) capsid binding. The phenotypic effects of these B-box 2 changes on the restriction of retroviral infection depended on the potency of restriction and the affinity of the TRIM5α interaction with the viral capsid, two properties specified by the …


Characterization Of Human Immunodeficiency Virus Type 1 Monomeric And Trimeric Gp120 Glycoproteins Stabilized In The Cd4-Bound State: Antigenicity, Biophysics, And Immunogenicity, Barna Dey, Marie Pancera, Krisha Svehla, Yuuei Shu, Shi-Hua Xiang, Jeffrey Vainshtein, Yuxing Li, Joseph Sodroski, Peter D. Kwong, John R. Mascola, Richard Wyatt Jan 2007

Characterization Of Human Immunodeficiency Virus Type 1 Monomeric And Trimeric Gp120 Glycoproteins Stabilized In The Cd4-Bound State: Antigenicity, Biophysics, And Immunogenicity, Barna Dey, Marie Pancera, Krisha Svehla, Yuuei Shu, Shi-Hua Xiang, Jeffrey Vainshtein, Yuxing Li, Joseph Sodroski, Peter D. Kwong, John R. Mascola, Richard Wyatt

Nebraska Center for Virology: Faculty Publications

The human immunodeficiency virus type 1 exterior gp120 envelope glycoprotein is highly flexible, and this flexibility may contribute to the inability of monomeric gp120 immunogens to elicit broadly neutralizing antibodies. We previously showed that an S375W modification of a critical interfacial cavity central to the primary receptor binding site, the Phe43 cavity, stabilizes gp120 into the CD4-bound state. However, the immunological effects of this cavity-altering replacement were never tested. Subsequently, we screened other mutations that, along with the S375W alteration, might further stabilize the CD4-bound state. Here, we define a selected second cavity-altering replacement, T257S, and analyze the double mutations …


Georgeoral Immunization Of Rhesus Macaques With Adenoviral Hiv Vaccines Using Enteric-Coated Capsules, George T. Mercier, Pramod N. Nehete, Marco F. Passeri, Bharti N. Nehete, Eric A. Weaver, Nancy Smyth Templeton, Kimberly Schluns, Stephanie S. Buchl, K. Jagannadha Sastry, Michael A. Barry Jan 2007

Georgeoral Immunization Of Rhesus Macaques With Adenoviral Hiv Vaccines Using Enteric-Coated Capsules, George T. Mercier, Pramod N. Nehete, Marco F. Passeri, Bharti N. Nehete, Eric A. Weaver, Nancy Smyth Templeton, Kimberly Schluns, Stephanie S. Buchl, K. Jagannadha Sastry, Michael A. Barry

Nebraska Center for Virology: Faculty Publications

Targeted delivery of vaccine candidates to the gastrointestinal (GI) tract holds potential for mucosal immunization, particularly against mucosal pathogens like the human immunodeficiency virus (HIV). Among the different strategies for achieving targeted release in the GI tract, namely the small intestine, pH sensitive enteric coating polymers have been shown to protect solid oral dosage forms from the harsh digestive environment of the stomach and dissolve relatively rapidly in the small intestine by taking advantage of the luminal pH gradient. We developed an enteric polymethacrylate formulation for coating hydroxy-propyl-methyl-cellulose (HPMC) capsules containing lyophilized Adenoviral type 5 (Ad5) vectors expressing HIV-1 gag …