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Full-Text Articles in Medicine and Health Sciences

Site-Specific Mutation Of The Sensor Kinase Gras In Staphylococcus Aureus Alters The Adaptive Response To Distinct Cationic Antimicrobial Peptides, Ambrose L. Cheung, Arnold S. Bayer, Michael R. Yeaman, Yan Q. Xiong, Alan J. Waring, Guido Memmi, Niles Donegan Dec 2014

Site-Specific Mutation Of The Sensor Kinase Gras In Staphylococcus Aureus Alters The Adaptive Response To Distinct Cationic Antimicrobial Peptides, Ambrose L. Cheung, Arnold S. Bayer, Michael R. Yeaman, Yan Q. Xiong, Alan J. Waring, Guido Memmi, Niles Donegan

Dartmouth Scholarship

The Staphylococcus aureus two-component regulatory system, GraRS, is involved in resistance to killing by distinct host defense cationic antimicrobial peptides (HD-CAPs). It is believed to regulate downstream target genes such as mprF and dltABCD to modify the S. aureus surface charge. However, the detailed mechanism(s) by which the histidine kinase, GraS, senses specific HD-CAPs is not well defined. Here, we studied a well-characterized clinical methicillin-resistant S. aureus (MRSA) strain (MW2), its isogenic graS deletion mutant (ΔgraS strain), a nonameric extracellular loop mutant (ΔEL strain), and four residue-specific ΔEL mutants (D37A, P39A, P39S, and D35G D37G D41G strains). The ΔgraS and …


Effects Of Dietary Preference On The Experience Of Anxiety, Depression And Acute Stress Response, Shaun Stearns Dec 2014

Effects Of Dietary Preference On The Experience Of Anxiety, Depression And Acute Stress Response, Shaun Stearns

Theses and Dissertations

Research has demonstrated that high saturated fat and low carbohydrate consumption may provide physiological benefit in the treatment of major neurological disorders, though not much research has explored if these benefits extend to the experience of anxiety, depression, stress and physical symptoms. The purpose of this study was to explore the relationship between fat consumption and negative emotional/physiological states (anxiety, depression, stress and physical symptoms). This study also explored how fat consumption can alter one's response to an acute stress. Participants completed an online survey indicating their food preferences and their responses to a number of self-report scales such as …


Acidosis Potentiates The Host Proinflammatory Interleukin-1Β Response To Pseudomonas Aeruginosa Infection, I. M. Torres, Y. R. Patankar, Tamer B. Shabaneh, E. Dolben, Deborah Hogan, David Leib, Brent L. Berwin Nov 2014

Acidosis Potentiates The Host Proinflammatory Interleukin-1Β Response To Pseudomonas Aeruginosa Infection, I. M. Torres, Y. R. Patankar, Tamer B. Shabaneh, E. Dolben, Deborah Hogan, David Leib, Brent L. Berwin

Dartmouth Scholarship

Infection by Pseudomonas aeruginosa, and bacteria in general, frequently promotes acidification of the local microenvironment, and this is reinforced by pulmonary exertion and exacerbation. However, the consequence of an acidic environment on the host inflammatory response to P. aeruginosa infection is poorly understood. Here we report that the pivotal cellular and host proinflammatory interleukin-1β (IL-1β) response, which enables host clearance of the infection but can produce collateral inflammatory damage, is increased in response to P. aeruginosa infection within an acidic environment. Synergistic mechanisms that promote increased IL-1β release in response to P. aeruginosa infection in an acidic environment are …


Analysis Of Candida Albicans Mutants Defective In The Cdk8 Module Of Mediator Reveal Links Between Metabolism And Biofilm Formation, Allia K. Lindsay, Diana K. Morales, Zhongle Liu, Nora Grahl, Anda Zhang, Sven D. Willger, Lawrence C. Myers, Deborah A. Hogan Oct 2014

Analysis Of Candida Albicans Mutants Defective In The Cdk8 Module Of Mediator Reveal Links Between Metabolism And Biofilm Formation, Allia K. Lindsay, Diana K. Morales, Zhongle Liu, Nora Grahl, Anda Zhang, Sven D. Willger, Lawrence C. Myers, Deborah A. Hogan

Dartmouth Scholarship

Candida albicans biofilm formation is a key virulence trait that involves hyphal growth and adhesin expression. Pyocyanin (PYO), a phenazine secreted by Pseudomonas aeruginosa, inhibits both C. albicans biofilm formation and development of wrinkled colonies. Using a genetic screen, we identified two mutants, ssn3Δ/Δ and ssn8Δ/Δ, which continued to wrinkle in the presence of PYO. Ssn8 is a cyclin-like protein and Ssn3 is similar to cyclin-dependent kinases; both proteins are part of the heterotetrameric Cdk8 module that forms a complex with the transcriptional co-regulator, Mediator. Ssn3 kinase activity was also required for PYO sensitivity as a kinase dead mutant maintained …


Structured Light Scatteroscopy, Venkataramanan Krishnaswamy, Jonathan T. Elliott, David M. Mcclatchy, Richard J. Barth Jr., Wendy A. Wells, Brian W. Pogue, Keith D. Paulsen Jul 2014

Structured Light Scatteroscopy, Venkataramanan Krishnaswamy, Jonathan T. Elliott, David M. Mcclatchy, Richard J. Barth Jr., Wendy A. Wells, Brian W. Pogue, Keith D. Paulsen

Dartmouth Scholarship

A new imaging approach, structured light scatteroscopy (SLS), is demonstrated, which offers rapid wide-field imaging of microscopic morphological variations in bulk tissue surfaces. Elastic scattering of light offers exquisite sensitivity to ultrastructural changes at multiple size scales ranging from nanometers to millimeters, but in bulk tissues the confounding effects of molecular absorption and strong multiple scattering of light often lead to a dramatic reduction in scatter contrast and specificity. It is demonstrated that the SLS using structured high spatial frequency illumination and detection to probe the tissue achieves direct, absorption-independent, high-resolution maps of the scattering response. The scattering response is …


Stag2 Promotes Error Correction In Mitosis By Regulating Kinetochore–Microtubule Attachments, Marianna Kleyman, Lilian Kabeche, Duane A. Compton Jul 2014

Stag2 Promotes Error Correction In Mitosis By Regulating Kinetochore–Microtubule Attachments, Marianna Kleyman, Lilian Kabeche, Duane A. Compton

Dartmouth Scholarship

Mutations in the STAG2 gene are present in ∼20% of tumors from different tissues of origin. STAG2 encodes a subunit of the cohesin complex, and tumors with loss-of-function mutations are usually aneuploid and display elevated frequencies of lagging chromosomes during anaphase. Lagging chromosomes are a hallmark of chromosomal instability (CIN) arising from persistent errors in kinetochore-microtubule (kMT) attachment. To determine whether the loss of STAG2 increases the rate of formation of kMT attachment errors or decreases the rate of their correction, we examined mitosis in STAG2-deficient cells. STAG2 depletion does not impair bipolar spindle formation or delay mitotic progression. Instead, …


Intrinsic Innate Immunity Fails To Control Herpes Simplex Virus And Vesicular Stomatitis Virus Replication In Sensory Neurons And Fibroblasts, Pamela C. Rosato, David A. Leib Jun 2014

Intrinsic Innate Immunity Fails To Control Herpes Simplex Virus And Vesicular Stomatitis Virus Replication In Sensory Neurons And Fibroblasts, Pamela C. Rosato, David A. Leib

Dartmouth Scholarship

Herpes simplex virus 1 (HSV-1) establishes lifelong latent infections in the sensory neurons of the trigeminal ganglia (TG), wherein it retains the capacity to reactivate. The interferon (IFN)-driven antiviral response is critical for the control of HSV-1 acute replication. We therefore sought to further investigate this response in TG neurons cultured from adult mice deficient in a variety of IFN signaling components. Parallel experiments were also performed in fibroblasts isolated concurrently. We showed that HSV-1 replication was comparable in wild-type (WT) and IFN signaling-deficient neurons and fibroblasts. Unexpectedly, a similar pattern was observed for the IFN-sensitive vesicular stomatitis virus (VSV). …


Physiological And Behavioural Responses To Noxious Stimuli In The Atlantic Cod (Gadus Morhua), Jared R. Eckroth, Øyvind Aas-Hansen, Lynne U. Sneddon, Helena Bichão, Kjell B. Døving Jun 2014

Physiological And Behavioural Responses To Noxious Stimuli In The Atlantic Cod (Gadus Morhua), Jared R. Eckroth, Øyvind Aas-Hansen, Lynne U. Sneddon, Helena Bichão, Kjell B. Døving

Aquaculture Collection

In the present study, our aim was to compare physiological and behavioural responses to different noxious stimuli to those of a standardized innocuous stimulus, to possibly identify aversive responses indicative of injury detection in a commercially important marine teleost fish, the Atlantic cod. Individual fish were administered with a noxious stimulus to the lip under short-term general anaesthesia (MS-222). The noxious treatments included injection of 0.1% or 2% acetic acid, 0.005% or 0.1% capsaicin, or piercing the lip with a commercial fishing hook. Counts of opercular beat rate (OBR) at 10, 30, 60, 90 and 120 min and observations of …


Structural Features Of The Pseudomonas Fluorescens Biofilm Adhesin Lapa Required For Lapg-Dependent Cleavage, Biofilm Formation, And Cell Surface Localization, Chelsea D. Boyd, T. Jarrod Smith, Sofiane El-Kirat-Chatel, Peter D. Newell, Yves F. Dufrêne, George A. O'Toole May 2014

Structural Features Of The Pseudomonas Fluorescens Biofilm Adhesin Lapa Required For Lapg-Dependent Cleavage, Biofilm Formation, And Cell Surface Localization, Chelsea D. Boyd, T. Jarrod Smith, Sofiane El-Kirat-Chatel, Peter D. Newell, Yves F. Dufrêne, George A. O'Toole

Dartmouth Scholarship

The localization of the LapA protein to the cell surface is a key step required by Pseudomonas fluorescens Pf0-1 to irreversibly attach to a surface and form a biofilm. LapA is a member of a diverse family of predicted bacterial adhesins, and although lacking a high degree of sequence similarity, family members do share common predicted domains. Here, using mutational analysis, we determine the significance of each domain feature of LapA in relation to its export and localization to the cell surface and function in biofilm formation. Our previous work showed that the N terminus of LapA is required for …


Lack Of Protection Following Passive Transfer Of Polyclonal Highly Functional Low-Dose Non-Neutralizing Antibodies, Anne-Sophie Dugast, Ying Chan, Michelle Hoffner, Anna Licht, Joseph Nkolola, Hualin Li, Hendrik Streeck, Todd J. Suscovich, Musie Ghebremichael, Margaret E. Ackerman, Dan H. Barouch, Galit Alter May 2014

Lack Of Protection Following Passive Transfer Of Polyclonal Highly Functional Low-Dose Non-Neutralizing Antibodies, Anne-Sophie Dugast, Ying Chan, Michelle Hoffner, Anna Licht, Joseph Nkolola, Hualin Li, Hendrik Streeck, Todd J. Suscovich, Musie Ghebremichael, Margaret E. Ackerman, Dan H. Barouch, Galit Alter

Dartmouth Scholarship

Recent immune correlates analysis from the RV144 vaccine trial has renewed interest in the role of non-neutralizing antibodies in mediating protection from infection. While neutralizing antibodies have proven difficult to induce through vaccination, extra-neutralizing antibodies, such as those that mediate antibody-dependent cellular cytotoxicity (ADCC), are associated with long-term control of infection. However, while several non-neutralizing monoclonal antibodies have been tested for their protective efficacy in vivo, no studies to date have tested the protective activity of naturally produced polyclonal antibodies from individuals harboring potent ADCC activity. Because ADCC-inducing antibodies are highly enriched in elite controllers (EC), we passively transferred …


Bodypump And The Rep Effect: An Instructor's Evaluation Of The Low-Weight, High-Repetition Group Exercise Program, Meredith Pritchett May 2014

Bodypump And The Rep Effect: An Instructor's Evaluation Of The Low-Weight, High-Repetition Group Exercise Program, Meredith Pritchett

Senior Theses

My senior thesis project was to become a certified Les Mills BODYPUMP instructor. In order to obtain my certification I had to go through training, which was paid for by the University of South Carolina. Training was a mentally and physically demanding weekend full of lifting weights and learning everything there is to know about BODYPUMP techniques, choreography, and coaching. Afterwards, I had sixty days to send in a video of myself teaching the class to a group of participants in order for my teaching skills to be evaluated by Les Mills. I passed my evaluation and am now a …


The Neuroscientific Study Of Spiritual Practices., Andrew B. Newberg, Md Mar 2014

The Neuroscientific Study Of Spiritual Practices., Andrew B. Newberg, Md

Marcus Institute of Integrative Health Faculty Papers

The purpose of this paper will be to provide a perspective on the current state of the research evaluating the neurobiological correlates of spiritual practices and review the methodological issues that confront this research field. There are many types of spiritual practices that might be studied including prayer and meditation, as well as unusual practices such as mediumistic trance states, speaking in tongues, and also drug-induced experiences. Current studies have utilized neuroimaging techniques including functional magnetic resonance imaging, single photon emission computed tomography, and positron emission tomography. These studies have helped elucidate the neurobiological mechanisms associated with spiritual practices. Such …


The Differential Interferon Responses Of Two Strains Of Stat1-Deficient Mice Do Not Alter Susceptibility To Hsv-1 And Vsv In Vivo, Sarah Katzenell, Yufei Chen, Zachary M. Parker, David A. Leib Feb 2014

The Differential Interferon Responses Of Two Strains Of Stat1-Deficient Mice Do Not Alter Susceptibility To Hsv-1 And Vsv In Vivo, Sarah Katzenell, Yufei Chen, Zachary M. Parker, David A. Leib

Dartmouth Scholarship

Stat1 is a pivotal transcription factor for generation of the interferon (IFN)-dependent antiviral response. Two Stat1 knockout mouse lines have been previously generated, one deleted the N-terminal domain (ΔNTD) and one in the DNA-binding domain (ΔDBD). These widely-used strains are assumed interchangeable, and both are highly susceptible to various pathogens. In this study, primary cells derived from ΔNTD mice were shown to be significantly more responsive to IFN, and established an antiviral state with greater efficiency than cells derived from ΔDBD mice, following infection with vesicular stomatitis virus and herpes simplex virus type-1. Also, while mice from both strains succumbed …


Roles Of Dopamine Receptor On Chemosensory And Mechanosensory Primary Cilia In Renal Epithelial Cells, Viralkumar S. Upadhyay, Brian S. Muntean, Samred H. Kathem, Jangyoun J. Hwang, Wissam A. Aboualaiwi, Surya M. Nauli Feb 2014

Roles Of Dopamine Receptor On Chemosensory And Mechanosensory Primary Cilia In Renal Epithelial Cells, Viralkumar S. Upadhyay, Brian S. Muntean, Samred H. Kathem, Jangyoun J. Hwang, Wissam A. Aboualaiwi, Surya M. Nauli

Pharmacy Faculty Articles and Research

Dopamine plays a number of important physiological roles. However, activation of dopamine receptor type-5 (DR5) and its effect in renal epithelial cells have not been studied. Here, we show for the first time that DR5 is localized to primary cilia of LLCPK kidney cells. Renal epithelial cilia are mechanosensory organelles that sense and respond to tubular fluid-flow in the kidney. To determine the roles of DR5 and sensory cilia, we used dopamine to non-selectively and fenoldopam to selectively activate ciliary DR5. Compared to mock treatment, dopamine treated cells significantly increases the length of cilia. Fenoldopam further increases the length of …


Importance Of Bacillithiol In The Oxidative Stress Response Of Staphylococcus Aureus, Ana C. Posada, Stacey L. Kolar, Renata G. Dusi, Patrica Francois Jan 2014

Importance Of Bacillithiol In The Oxidative Stress Response Of Staphylococcus Aureus, Ana C. Posada, Stacey L. Kolar, Renata G. Dusi, Patrica Francois

Dartmouth Scholarship

In Staphylococcus aureus, the low-molecular-weight thiol called bacillithiol (BSH), together with cognate S-transferases, is believed to be the counterpart to the glutathione system of other organisms. To explore the physiological role of BSH in S. aureus, we constructed mutants with the deletion of bshA (sa1291), which encodes the glycosyltransferase that catalyzes the first step of BSH biosynthesis, and fosB (sa2124), which encodes a BSH-S-transferase that confers fosfomycin resistance, in several S. aureus strains, including clinical isolates. Mutation of fosB or bshA caused a 16- to 60-fold reduction in fosfomycin resistance in these S. aureus strains. High-pressure liquid chromatography analysis, which …


Novel Roles For Actin In Mitochondrial Fission, Anna L. Hatch, Pinar S. Gurel, Henry N. Higgs Jan 2014

Novel Roles For Actin In Mitochondrial Fission, Anna L. Hatch, Pinar S. Gurel, Henry N. Higgs

Dartmouth Scholarship

Mitochondrial dynamics, including fusion, fission and translocation, are crucial to cellular homeostasis, with roles in cellular polarity, stress response and apoptosis. Mitochondrial fission has received particular attention, owing to links with several neurodegenerative diseases. A central player in fission is the cytoplasmic dynamin-related GTPase Drp1, which oligomerizes at the fission site and hydrolyzes GTP to drive membrane ingression. Drp1 recruitment to the outer mitochondrial membrane (OMM) is a key regulatory event, which appears to require a pre-constriction step in which the endoplasmic reticulum (ER) and mitochondrion interact extensively, a process termed ERMD (ER-associated mitochondrial division). It is unclear how ER-mitochondrial …


Anti-Müllerian Hormone In Stallions And Mares: Physiological Variations, Clinical Applications, And Molecular Aspects, Anthony N.J. Claes Jan 2014

Anti-Müllerian Hormone In Stallions And Mares: Physiological Variations, Clinical Applications, And Molecular Aspects, Anthony N.J. Claes

Theses and Dissertations--Veterinary Science

Anti-Müllerian hormone (AMH) is a homodimeric glycoprotein that is best known for its role in regression of the Müllerian duct in the male fetus. Accumulating evidence indicates that AMH also has an important role during different physiological processes after birth. In contrast to other species, relatively little is known about AMH in the horse. In chapter one, developmental and seasonal changes in serum AMH concentrations in male horses were determined, and the use of AMH for determination of retained cryptorchid testes was established. In chapter two, the interrelationship between plasma AMH concentrations, antral follicle counts (AFC), and age in mares …


The Efficacy Of Long-Term Kinesio Tape On Grip Strength In A Healthy Population, Neel Kotrappa Jan 2014

The Efficacy Of Long-Term Kinesio Tape On Grip Strength In A Healthy Population, Neel Kotrappa

CMC Senior Theses

Kinesio® Tape was invented in 1973, and since has been used in various clinical and therapy settings to prevent and heal a multitude of physical conditions. Kinesio® Tape is a 100% cotton-based elastic tape that when applied to the skin pulls the skin upwards and creates more space by lifting the fascia and soft tissue, thus increasing blood flow and decreasing edema. The tape was also purported to facilitate the strengthening of weakened muscles through neuromuscular facilitation. The objective behind this study was to determine the long-term effects of applied forearm Kinesio® Tape on maximal grip strength when paired with …


Insulin Regulates Glucose Consumption And Lactate Production Through Reactive Oxygen Species And Pyruvate Kinase M2., Qi Li, Xue Liu, Yu Yin, Ji-Tai Zheng, Cheng-Fei Jiang, Jing Wang, Hua Shen, Chong-Yong Li, Min Wang, Ling-Zhi Liu, Bing-Hua Jiang Jan 2014

Insulin Regulates Glucose Consumption And Lactate Production Through Reactive Oxygen Species And Pyruvate Kinase M2., Qi Li, Xue Liu, Yu Yin, Ji-Tai Zheng, Cheng-Fei Jiang, Jing Wang, Hua Shen, Chong-Yong Li, Min Wang, Ling-Zhi Liu, Bing-Hua Jiang

Department of Pathology, Anatomy, and Cell Biology Faculty Papers

Although insulin is known to regulate glucose metabolism and closely associate with liver cancer, the molecular mechanisms still remain to be elucidated. In this study, we attempt to understand the mechanism of insulin in promotion of liver cancer metabolism. We found that insulin increased pyruvate kinase M2 (PKM2) expression through reactive oxygen species (ROS) for regulating glucose consumption and lactate production, key process of glycolysis in hepatocellular carcinoma HepG2 and Bel7402 cells. Interestingly, insulin-induced ROS was found responsible for the suppression of miR-145 and miR-128, and forced expression of either miR-145 or miR-128 was sufficient to abolish insulin-induced PKM2 expression. …