Medicine and Health Sciences | Open Access Articles

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

Masters Theses

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

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Shortening Sow Restraint Period During Lactation Improves Production And Decreases Hair Cortisol Concentrations In Sows And Their Piglets, L. Morgan, J. Meyer, S. Novak, A. Younis, W.A. Ahmad, T. Raz

Elaine Marieb College of Nursing Faculty Publication Series

Food animal welfare is an issue of great concern, as society has a responsibility for animals under human care. Pork is the most consumed meat worldwide, with more than a billion pigs being slaughtered globally every year. Still, in most countries, sows are restrained in farrowing crates throughout lactation. In these crates, sows arc confined with bars to an area that is just slightly larger than their body. Thus, moving and turning around, grooming, or expressing other natural behaviors are typically impossible. In this study, we utilized a simple and practical modification of conventional farrowing crates to designed farrowing pens, …

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Microtransplantation Of Rat Brain Neurolemma Into Xenopus Laevis Oocytes To Study The Effect Of Environmental Toxicants On Endogenous Voltage-Sensitive Ion Channels, Edwin Murenzi

Masters Theses

Microtransplantation of mammalian neurolemma into Xenopus laevis oocytes has been used to study ion channels in terms of their structure and function in the central nervous system. Use of microtransplanted neurolemma is advantageous in that tissue can be obtained from various sources, ion channels and receptors are present in their native configuration and they can be used to evaluate numerous channelpathies caused by environmental toxicants. Here we show that Xenopus oocytes injected with fragments of rat brain neurolemma successfully express functional native ion channels that are assembled in their own plasma membrane. Using a high throughput two electrode voltage clamp …

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Tyrosine Kinase-Mediated Axial Motility Of Basal Cells Revealed By Intravital Imaging, Jeremy Roy, Bongki Kim, Eric Hill, Pablo Visconti, Dario Krapf, Claudio Vinegoni, Ralph Weissleder, Dennis Brown, Sylvie Breton

Veterinary & Animal Sciences Department Faculty Publication Series

Epithelial cells are generally considered to be static relative to their neighbours. Basal cells in pseudostratified epithelia display a single long cytoplasmic process that can cross the tight junction barrier to reach the lumen. Using in vivo microscopy to visualize the epididymis, a model system for the study of pseudostratified epithelia, we report here the surprising discovery that these basal cell projections—which we call axiopodia—periodically extend and retract over time. We found that axiopodia extensions and retractions follow an oscillatory pattern. This movement, which we refer to as periodic axial motility (PAM), is controlled by c-Src and MEK1/2–ERK1/2. Therapeutic inhibition …

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The Human Intruder Test: An Anxiety Assessment In Rhesus Macaques (Macaca Mulatta), Emily J. Peterson

Masters Theses

The human intruder test (HIT) is a noninvasive tool widely used for assessing anxiety in rhesus macaques (Macaca mulatta). This thesis explores the HIT procedure and applies it to a population of monkeys with a self-injurious behavioral pathology. Individual variation on this test can be used to assess anxiety and temperament. The first experiment of this thesis applied two different procedures of the HIT to 17 monkeys at UMass. Monkeys displayed little response to the intruder, and no significant differences were detected for the two procedures. To determine whether these responses were unique to the UMass monkeys, their …

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Cd4 Silencing In Thymocytes Is Opposed By The Enforced Association Of P300 Hat, Hdac1 Or Suv39h1 With Runx Transcription Factors, Christyne Ayne Kane

Doctoral Dissertations

The transcription factors Runx1 and Runx3 are required for permanent silencing of CD4 in maturing CD8+ thymocytes. Runx binding to consensus sites within the CD4 silencer region is required for CD4 silencing post-positive selection. The Runx nuclear matrix targeting sequence (NMTS) is required for CD4 silencing and is implicated in binding to the histone acetyltransferase (HAT) p300, histone deacetylases (HDAC), and histone methyltransferase (HMT) SUV39H1 proteins. Epigenetic modifications of chromatin or post-translational modifications of Runx itself as a result of Runx association with these enzymes may be important for establishment of long-term CD4 silencing. In this study, we show that …

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Oncogenic Transformation Of Mammary Epithelial Cells By Transforming Growth Factor Beta Independent Of Mammary Stem Cell Regulation, Karen Dunphy, Jae-Hong Seo, Daniel J. Kim, Amy L. Roberts, Luwei Tao, James Direnzo, Amanda L. Balboni, Giovanna M. Crisi, Mary J. Hagen, Thiruppavai Chandrasekaran, Kelly J. Gauger, Sallie Smith Schneider, D Joseph Jerry

Karen Dunphy

Background: Transforming growth factor beta (TGFβ) is transiently increased in the mammary gland during involution and by radiation. While TGFβ normally has a tumour suppressor role, prolonged exposure to TGFβ can induce an oncogenic epithelial to mesenchymal transition (EMT) program in permissive cells and initiate the generation of cancer stem cells. Our objective is to mimic the transient exposure to TGFβ during involution to determine the persistent effects on premalignant mammary epithelium. Method: CDβGeo cells, a transplantable mouse mammary epithelial cell line, were treated in vitro for 14 days with TGFβ (5 ng/ml). The cells were passaged for an additional …

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Oncogenic Transformation Of Mammary Epithelial Cells By Transforming Growth Factor Beta Independent Of Mammary Stem Cell Regulation, Karen A. Dunphy, Jae-Hong Seo, Daniel J. Kim, Amy L. Roberts, Luwei Tao, James Direnzo, Amanda L. Balboni, Giovanna M. Crisi, Mary J. Hagen, Thiruppavai Chandrasekaran, Kelly J. Gauger, Sallie Smith Schneider, D. Joseph Jerry

D. Joseph Jerry

Background: Transforming growth factor beta (TGFβ) is transiently increased in the mammary gland during involution and by radiation. While TGFβ normally has a tumour suppressor role, prolonged exposure to TGFβ can induce an oncogenic epithelial to mesenchymal transition (EMT) program in permissive cells and initiate the generation of cancer stem cells. Our objective is to mimic the transient exposure to TGFβ during involution to determine the persistent effects on premalignant mammary epithelium. Method: CDβGeo cells, a transplantable mouse mammary epithelial cell line, were treated in vitro for 14 days with TGFβ (5 ng/ml). The cells were passaged for an additional …

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Transient Pharmacologic Lowering Of Aβ Production Prior To Deposition Results In Sustained Reduction Of Amyloid Plaque Pathology, Pritam Das, Christophe Verbeeck, Lisa Minter, Paramita Chakrabarty, Kevin Felsentein, Thomas Kukar, Ghulam Maharvi, Abdul Fauq, Barbara A. Osborne, Todd E. Golde

Lisa Minter

Background: Alzheimer’s disease (AD) is the leading cause of dementia among the elderly. Disease modifying therapies targeting Aβ that are in development have been proposed to be more effective if treatment was initiated prior to significant accumulation of Aβ in the brain, but optimal timing of treatment initiation has not been clearly established in the clinic. We compared the efficacy of transient pharmacologic reduction of brain Aβ with a γ-secretase inhibitor (GSI ) for 1–3 months (M) treatment windows in APP Tg2576 mice and subsequent aging of the mice to either 15M or 18M. Results: These data show that reducing …

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Radiation Acts On The Microenvironment To Affect Breast Carcinogenesis By Distinct Mechanisms That Decrease Cancer Latency And Affect Tumor Type, Karen Dunphy, D.H. Nguyen, H.A. Oketch-Rabah, I. Illa-Bochaca, F.C. Geyer, J.S. Reis-Filho, J.H. Mao, S.A. Ravani, J. Zavadil, A.D. Borowsky, J.D. Jeryy

Karen Dunphy

Tissue microenvironment is an important determinant of carcinogenesis. We demonstrate that ionizing radiation, a known carcinogen, affects cancer frequency and characteristics by acting on the microenvironment. Using a mammary chimera model in which an irradiated host is transplanted with oncogenic Trp53 null epithelium, we show accelerated development of aggressive tumors whose molecular signatures were distinct from tumors arising in nonirradiated hosts. Molecular and genetic approaches show that TGFβ mediated tumor acceleration. Tumor molecular signatures implicated TGFβ, and genetically reducing TGFβ abrogated the effect on latency. Surprisingly, tumors from irradiated hosts were predominantly estrogen receptor negative. This effect was TGFβ independent …

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Repression Of Mammary Stem/Progenitor Cells By P53 Is Mediated By Notch And Separable From Apoptotic Activity, Karen Dunphy, L. Tao, C. Bigelow, H. Yan, J.D. Jerry

Karen Dunphy

Breast cancer is the most common tumor among women with inherited mutations in the p53 gene (Li-Fraumeni syndrome). The tumors represent the basal-like subtype, which has been suggested to originate from mammary stem/progenitor cells. In mouse mammary epithelium, mammosphere-forming potential was increased with decreased dosage of the gene encoding the p53 tumor suppressor protein (Trp53). Limiting dilution transplantation also showed a 3.3-fold increase in the frequency of long-term regenerative mammary stem cells in Trp53−/− mice. The repression of mammospheres by p53 was apparent despite the absence of apoptotic responses to radiation indicating a dissociation of these two activities of p53. …

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Estrogen And Progesterone Induce Persistent Increases In P53-Dependent Apoptosis And Suppress Mammary Tumors In Balb/C-Trp53+/- Mice, Karen Dunphy, Anneke C. Blackburn, Haoheng Yan, Lauren R. O'Connell, D Joseph Jerry

Karen Dunphy

Introduction Treatment with estrogen and progesterone (E+P) mimics the protective effect of parity on mammary tumors in rodents and depends upon the activity of p53. The following experiments tested whether exogenous E+P primes p53 to be more responsive to DNA damage and whether these pathways confer resistance to mammary tumors in a mouse model of Li-Fraumeni syndrome. Methods Mice that differ in p53 status (Trp53+/+, Trp53+/-, Trp53-/-) were treated with E+P for 14 days and then were tested for p53-dependent responses to ionizing radiation. Responses were also examined in parous and age-matched virgins. The effects of hormonal exposures on tumor …

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Regulation Of Rac1 Activation By The Low Density Lipoprotein Receptor–Related Protein, Zhong Ma, Keena S. Thomas, Donna J. Webb, Radim Moravec, Ana Maria Salicioni, Wendy M. Mars, Steven L. Gonias

Ana Maria Salicioni

The low density lipoprotein receptor–related protein (LRP-1) binds and mediates the endocytosis of multiple ligands, transports the urokinase-type plasminogen activator receptor (uPAR) and other membrane proteins into endosomes, and binds intracellular adaptor proteins involved in cell signaling. In this paper, we show that in murine embryonic fibroblasts (MEFs) and L929 cells, LRP-1 functions as a major regulator of Rac1 activation, and that this activity depends on uPAR. LRP-1–deficient MEFs demonstrated increased Rac1 activation compared with LRP-1–expressing MEFs, and this property was reversed by expressing the VLDL receptor, a member of the same gene family as LRP-1, with overlapping ligand-binding specificity. …

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Full-Text Articles in Medicine and Health Sciences

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

Masters Theses

Shortening Sow Restraint Period During Lactation Improves Production And Decreases Hair Cortisol Concentrations In Sows And Their Piglets, L. Morgan, J. Meyer, S. Novak, A. Younis, W.A. Ahmad, T. Raz

Elaine Marieb College of Nursing Faculty Publication Series

Microtransplantation Of Rat Brain Neurolemma Into Xenopus Laevis Oocytes To Study The Effect Of Environmental Toxicants On Endogenous Voltage-Sensitive Ion Channels, Edwin Murenzi

Masters Theses

Tyrosine Kinase-Mediated Axial Motility Of Basal Cells Revealed By Intravital Imaging, Jeremy Roy, Bongki Kim, Eric Hill, Pablo Visconti, Dario Krapf, Claudio Vinegoni, Ralph Weissleder, Dennis Brown, Sylvie Breton

Veterinary & Animal Sciences Department Faculty Publication Series

The Human Intruder Test: An Anxiety Assessment In Rhesus Macaques (Macaca Mulatta), Emily J. Peterson

Masters Theses

Cd4 Silencing In Thymocytes Is Opposed By The Enforced Association Of P300 Hat, Hdac1 Or Suv39h1 With Runx Transcription Factors, Christyne Ayne Kane

Doctoral Dissertations

Karen Dunphy

D. Joseph Jerry

Transient Pharmacologic Lowering Of Aβ Production Prior To Deposition Results In Sustained Reduction Of Amyloid Plaque Pathology, Pritam Das, Christophe Verbeeck, Lisa Minter, Paramita Chakrabarty, Kevin Felsentein, Thomas Kukar, Ghulam Maharvi, Abdul Fauq, Barbara A. Osborne, Todd E. Golde

Lisa Minter

Radiation Acts On The Microenvironment To Affect Breast Carcinogenesis By Distinct Mechanisms That Decrease Cancer Latency And Affect Tumor Type, Karen Dunphy, D.H. Nguyen, H.A. Oketch-Rabah, I. Illa-Bochaca, F.C. Geyer, J.S. Reis-Filho, J.H. Mao, S.A. Ravani, J. Zavadil, A.D. Borowsky, J.D. Jeryy

Karen Dunphy

Repression Of Mammary Stem/Progenitor Cells By P53 Is Mediated By Notch And Separable From Apoptotic Activity, Karen Dunphy, L. Tao, C. Bigelow, H. Yan, J.D. Jerry

Karen Dunphy

Estrogen And Progesterone Induce Persistent Increases In P53-Dependent Apoptosis And Suppress Mammary Tumors In Balb/C-Trp53+/- Mice, Karen Dunphy, Anneke C. Blackburn, Haoheng Yan, Lauren R. O'Connell, D Joseph Jerry

Karen Dunphy

Regulation Of Rac1 Activation By The Low Density Lipoprotein Receptor–Related Protein, Zhong Ma, Keena S. Thomas, Donna J. Webb, Radim Moravec, Ana Maria Salicioni, Wendy M. Mars, Steven L. Gonias

Ana Maria Salicioni