Digital Commons Network^™

Actin Filaments Target The Oligomeric Maturation Of The Dynamin Gtpase Drp1 To Mitochondrial Fission Sites, Wei-Ke Ji, Anna L. Hatch, Ronald A. Merrill, Stefan Strack, Henry N. Higgs

Dartmouth Scholarship

While the dynamin GTPase Drp1 plays a critical role during mitochondrial fission, mechanisms controlling its recruitment to fission sites are unclear. A current assumption is that cytosolic Drp1 is recruited directly to fission sites immediately prior to fission. Using live-cell microscopy, we find evidence for a different model, progressive maturation of Drp1 oligomers on mitochondria through incorporation of smaller mitochondrially-bound Drp1 units. Maturation of a stable Drp1 oligomer does not forcibly lead to fission. Drp1 oligomers also translocate directionally along mitochondria. Ionomycin, a calcium ionophore, causes rapid mitochondrial accumulation of actin filaments followed by Drp1 accumulation at the fission site, …

Cyclin-Dependent Kinase Inhibitor P1446a Induces Apoptosis In A Jnk/P38 Mapk-Dependent Manner In Chronic Lymphocytic Leukemia B-Cells, Cody Paiva, J. Claire Godbersen, Ryan S. Soderquist, Taylor Rowland, Sumner Kilmarx

Dartmouth Scholarship

CDK (cyclin-dependent kinase) inhibitors have shown remarkable activity in CLL, where its efficacy has been linked to inhibition of the transcriptional CDKs (7 and 9) and deregulation of RNA polymerase and short-lived pro-survival proteins such as MCL1. Furthermore, ER (endoplasmic reticulum) stress has been implicated in CDK inhibition in CLL. Here we conducted a pre-clinical study of a novel orally active kinase inhibitor P1446A in CLL B-cells. P1446A inhibited CDKs at nanomolar concentrations and induced rapid apoptosis of CLL cells in vitro, irrespective of chromosomal abnormalities or IGHV mutational status. Apoptosis preceded inactivation of RNA polymerase, and was accompanied by …

Progressive Hearing Loss In Mice Carrying A Mutation In Usp53, Marcin Kazmierczak, Suzan L. Harris, Piotr Kazmierczak, Prahar Shah, Valentin Starovoytov, Kevin K. Ohlemiller, Martin Schwander

Open Access Publications

UNLABELLED: Disordered protein ubiquitination has been linked to neurodegenerative disease, yet its role in inner ear homeostasis and hearing loss is essentially unknown. Here we show that progressive hearing loss in the ethylnitrosourea-generated mambo mouse line is caused by a mutation in Usp53, a member of the deubiquitinating enzyme family. USP53 contains a catalytically inactive ubiquitin-specific protease domain and is expressed in cochlear hair cells and a subset of supporting cells. Although hair cell differentiation is unaffected in mambo mice, outer hair cells degenerate rapidly after the first postnatal week. USP53 colocalizes and interacts with the tight junction scaffolding proteins …

Systematic Analysis Of Hematopoietic Gene Expression Profiles For Prognostic Prediction In Acute Myeloid Leukemia, Frederick S. Varn, Erik H. Andrews, Chao Cheng

Dartmouth Scholarship

Acute myeloid leukemia (AML) is a hematopoietic disorder initiated by the leukemogenic transformation of myeloid cells into leukemia stem cells (LSCs). Preexisting gene expression programs in LSCs can be used to assess their transcriptional similarity to hematopoietic cell types. While this relationship has previously been examined on a small scale, an analysis that systematically investigates this relationship throughout the hematopoietic hierarchy has yet to be implemented. We developed an integrative approach to assess the similarity between AML patient tumor profiles and a collection of 232 murine hematopoietic gene expression profiles compiled by the Immunological Genome Project. The resulting lineage similarity …

Detection Of Sleep Disordered Breathing In Patients Hospitalized With Congestive Heart Failure, Sunil Sharma, Paul Mather

Department of Sleep Medicine Faculty Papers

OBJECTIVES: The purpose of this study was to evaluate the plethysmographic signal-derived oxygen desaturation index (ODI) as an inpatient screening strategy to identify sleep-disordered breathing (SDB) in patients with congestive heart failure (CHF).

BACKGROUND: SDB is highly prevalent among patients hospitalized with CHF but is widely underdiagnosed. We evaluated overnight photoplethysmography as a possible screening strategy for hospitalized patients with CHF.

METHODS: Consecutively admitted heart failure patients with high clinical suspicion of SDB and ODI ≥5 were offered outpatient polysomnography (PSG), which was completed within 4 weeks of discharge. PSG was considered positive if the apnea hypoxia index (AHI) was …

Role Of Micrornas In Alcohol-Induced Multi-Organ Injury., Sathish Kumar Natarajan, Joseph M. Pachunka, Justin L. Mott

Journal Articles: Biochemistry & Molecular Biology

Alcohol consumption and its abuse is a major health problem resulting in significant healthcare cost in the United States. Chronic alcoholism results in damage to most of the vital organs in the human body. Among the alcohol-induced injuries, alcoholic liver disease is one of the most prevalent in the United States. Remarkably, ethanol alters expression of a wide variety of microRNAs that can regulate alcohol-induced complications or dysfunctions. In this review, we will discuss the role of microRNAs in alcoholic pancreatitis, alcohol-induced liver damage, intestinal epithelial barrier dysfunction, and brain damage including altered hippocampus structure and function, and neuronal loss, …

Cost Effectiveness Analysis Of Year 2 Of An Elementary School-Located Influenza Vaccination Program-Results From A Randomized Controlled Trial., Byung-Kwang Yoo, Sharon Humiston, Peter G. Szilagyi, Stanley J. Schaffer, Christine Long, Maureen Kolasa

Manuscripts, Articles, Book Chapters and Other Papers

BACKGROUND: School-located vaccination against influenza (SLV-I) has the potential to improve current suboptimal influenza immunization coverage for U.S. school-aged children. However, little is known about SLV-I's cost-effectiveness. The objective of this study is to establish the cost-effectiveness of SLV-I based on a two-year community-based randomized controlled trial (Year 1: 2009-2010 vaccination season, an unusual H1N1 pandemic influenza season, and Year 2: 2010-2011, a more typical influenza season).

METHODS: We performed a cost-effectiveness analysis on a two-year randomized controlled trial of a Western New York SLV-I program. SLV-I clinics were offered in 21 intervention elementary schools (Year 1 n = 9,027; …

Successful Vim Targeting For Mixed Essential And Parkinsonian Tremor Using Intraoperative Mri, Christos Sidiropoulos, Lynn Mubita, Shana Krstevska, Jason M. Schwalb

Neurosurgery Articles

No abstract provided.

Emerging Immunopharmacological Targets In Multiple Sclerosis., Mojtaba Farjam, Guang-Xian Zhang, Bogoljub Ciric, Abdolmohamad Rostami

Department of Neurology Faculty Papers

Inflammatory demyelination of the central nervous system (CNS) is the hallmark of multiple sclerosis (MS), a chronic debilitating disease that affects more than 2.5 million individuals worldwide. It has been widely accepted, although not proven, that the major pathogenic mechanism of MS involves myelin-reactive T cell activation in the periphery and migration into the CNS, which subsequently triggers an inflammatory cascade that leads to demyelination and axonal damage. Virtually all MS medications now in use target the immune system and prevent tissue damage by modulating neuroinflammatory processes. Although current therapies such as commonly prescribed disease-modifying medications decrease the relapse rate …

A Forward Genetic Screen Reveals Novel Independent Regulators Of Ulbp1, An Activating Ligand For Natural Killer Cells, Benjamin G Gowen, Bryan Chim, Caleb D. Marceau, Trever T Greene, Patrick Burr, Jeanmarie R. Gonzalez, Charles Hesser, Peter A. Dietzen, Teal Russell, Alexandre Iannello, Laurent Coscoy, Charles L. Sentman

Dartmouth Scholarship

Recognition and elimination of tumor cells by the immune system is crucial for limiting tumor growth. Natural killer (NK) cells become activated when the receptor NKG2D is engaged by ligands that are frequently upregulated in primary tumors and on cancer cell lines. However, the molecular mechanisms driving NKG2D ligand expression on tumor cells are not well defined. Using a forward genetic screen in a tumor-derived human cell line, we identified several novel factors supporting expression of the NKG2D ligand ULBP1. Our results show stepwise contributions of independent pathways working at multiple stages of ULBP1 biogenesis. Deeper investigation of selected hits …

A Cytosolic Multiprotein Complex Containing P85Α Is Required For Β-Catenin Activation In Colitis And Colitis-Associated Cancer, Tatiana Goretsky, Emily M. Bradford, Hyunji Ryu, Maryam Tahir, Mary Pat Moyer, Tianyan Gao, Linheng Li, Terrence A. Barrett

Internal Medicine Faculty Publications

Wnt/β-catenin signaling is required for crypt structure maintenance. We previously observed nuclear accumulation of Ser-552 phosphorylated β-catenin (pβ-Cat^Ser-552) in intestinal epithelial cells (IEC) during colitis and colitis-associated cancer. Data here delineate a novel multiprotein cytosolic complex (MCC) involved in β-catenin signaling in the intestine. The MCC contains p85α, the class IA subunit of PI3K, along with β-catenin, 14-3-3ζ, Akt, and p110α. MCC levels in IEC increase in colitis and colitis-associated cancer patients. IEC-specific p85α-deficient (p85^ΔIEC) mice develop more severe dextran sodium …

Age-Associated Methylation Suppresses Spry1, Leading To A Failure Of Re-Quiescence And Loss Of The Reserve Stem Cell Pool In Elderly Muscle., Anne Bigot, William J Duddy, Zamalou G Ouandaogo, Elisa Negroni, Virginie Mariot, Svetlana Ghimbovschi, Brennan Harmon, Aurore Wielgosik, Camille Loiseau, Joseph Devaney, Julie Dumonceaux, Gillian Butler-Browne, Vincent Mouly, Stéphanie Duguez

Genomics and Precision Medicine Faculty Publications

The molecular mechanisms by which aging affects stem cell number and function are poorly understood. Murine data have implicated cellular senescence in the loss of muscle stem cells with aging. Here, using human cells and by carrying out experiments within a strictly pre-senescent division count, we demonstrate an impaired capacity for stem cell self-renewal in elderly muscle. We link aging to an increased methylation of the SPRY1 gene, a known regulator of muscle stem cell quiescence. Replenishment of the reserve cell pool was modulated experimentally by demethylation or siRNA knockdown of SPRY1. We propose that suppression of SPRY1 by age-associated …

Critical Shortage Of African American Medical Oncologists In The United States, Lauren M. Hamel, Robert Chapman, Mary Malloy, Susan Eggly, Louis A. Penner, Anthony F. Shields, Michael S. Simon, Justin F. Klamerus, Charles Schiffer, Terrence L. Albrecht

Hematology/Oncology Articles

No abstract provided.

Monomethylarsonous Acid (Mmaiii) Has An Adverse Effect On The Innate Immune Response Of Human Bronchial Epithelial Cells To Pseudomonas Aeruginosa, Emily G. Notch, Britton C. Goodale, Roxanna Barnaby, Bonita Coutermarsh, Brent Berwin, Vivien F. Taylor, Brian P. Jackson, Bruce A. Stanton

Dartmouth Scholarship

Arsenic is the number one contaminant of concern with regard to human health according to the World Health Organization. Epidemiological studies on Asian and South American populations have linked arsenic exposure with an increased incidence of lung disease, including pneumonia, and chronic obstructive pulmonary disease, both of which are associated with bacterial infection. However, little is known about the effects of low dose arsenic exposure, or the contributions of organic arsenic to the innate immune response to bacterial infection. This study examined the effects on Pseudomonas aeruginosa (P. aeruginosa) induced cytokine secretion by human bronchial epithelial cells (HBEC) …

Propagated Infra-Slow Intrinsic Brain Activity Reorganizes Across Wake And Slow Wave Sleep, Anish Mitra, Abraham Z. Snyder, Enzo Tagliazucchi, Helmut Laufs, Marcus E. Raichle

Open Access Publications

Propagation of slow intrinsic brain activity has been widely observed in electrophysiogical studies of slow wave sleep (SWS). However, in human resting state fMRI (rs-fMRI), intrinsic activity has been understood predominantly in terms of zero-lag temporal synchrony (functional connectivity) within systems known as resting state networks (RSNs). Prior rs-fMRI studies have found that RSNs are generally preserved across wake and sleep. Here, we use a recently developed analysis technique to study propagation of infra-slow intrinsic blood oxygen level dependent (BOLD) signals in normal adults during wake and SWS. This analysis reveals marked changes in propagation patterns in SWS vs. wake. …

Serum Iron Level Is Associated With Time To Antibiotics In Cystic Fibrosis, Alex H. Gifford, Dana B. Dorman, Lisa A. Moulton, Jennifer E. Helm, Mary M. Griffin, Todd A. Mackenzie

Dartmouth Scholarship

Background:

Serum levels of hepcidin‐25, a peptide hormone that reduces blood iron content, are elevated when patients with cystic fibrosis (CF) develop pulmonary exacerbation (PEx). Because hepcidin‐25 is unavailable as a clinical laboratory test, we questioned whether a one‐time serum iron level was associated with the subsequent number of days until PEx, as defined by the need to receive systemic antibiotics (ABX) for health deterioration.

Methods:

Clinical, biochemical, and microbiological parameters were simultaneously checked in 54 adults with CF. Charts were reviewed to determine when they first experienced a PEx after these parameters were assessed. Time to ABX was compared …

Antioncogenic And Oncogenic Properties Of Nrf2 In Arsenic-Induced Carcinogenesis, Young-Ok Son, Poyil Pratheeshkumar, Ram Vinod Roy, Andrew Hitron, Lei Wang, Sasidharan Padmaja Divya, Mei Xu, Jia Luo, Gang Chen, Zhuo Zhang, Xianglin Shi

Center for Research on Environmental Disease Faculty Publications

Arsenic (As³⁺) is a carcinogen with considerable environmental and occupational relevancy. The present study shows that As³⁺-transformed human lung bronchial epithelial BEAS-2B cells (AsT cells) exhibit the property of apoptosis resistance. The level of basal reactive oxygen species (ROS) is very low in AsT cells in correlation with elevated expressions of both antioxidant enzymes and antiapoptotic proteins. Nuclear factor erythroid 2-related factor (Nrf2) and p62 are constitutively expressed. These two proteins up-regulate antioxidant enzymes and antiapoptotic proteins. The knockdown of Nrf2 or p62 by small interfering RNA (siRNA) enhanced both ROS levels and As³⁺-induced …

Integrin Α6Β4 Promotes Autocrine Epidermal Growth Factor Receptor (Egfr) Signaling To Stimulate Migration And Invasion Toward Hepatocyte Growth Factor (Hgf), Brittany L. Carpenter, Min Chen, Teresa Knifley, Kelley A. Davis, Susan M.W. Harrison, Rachel L. Stewart, Kathleen O'Connor

Markey Cancer Center Faculty Publications

Integrin α6β4 is up-regulated in pancreatic adenocarcinomas where it contributes to carcinoma cell invasion by altering the transcriptome. In this study, we found that integrin α6β4 up-regulates several genes in the epidermal growth factor receptor (EGFR) pathway, including amphiregulin (AREG), epiregulin (EREG), and ectodomain cleavage protease MMP1, which is mediated by promoter demethylation and NFAT5. The correlation of these genes with integrin α6β4 was confirmed in The Cancer Genome Atlas Pancreatic Cancer Database. Based on previous observations that integrin α6β4 cooperates with c-Met in pancreatic cancers, we examined the impact of EGFR signaling on hepatocyte growth factor (HGF)-stimulated migration and …

Pleiotropic Effects Of Immune Responses Explain Variation In The Prevalence Of Fibroproliferative Diseases, Shirley B. Russell, Joan C. Smith, Minjun Huang, Joel S. Trupin, Scott M. Williams

Dartmouth Scholarship

Many diseases are differentially distributed among human populations. Differential selection on genetic variants in ancestral environments that coincidentally predispose to disease can be an underlying cause of these unequal prevalence patterns. Selected genes may be pleiotropic, affecting multiple phenotypes and resulting in more than one disease or trait. Patterns of pleiotropy may be helpful in understanding the underlying causes of an array of conditions in a population. For example, several fibroproliferative diseases are more prevalent and severe in populations of sub-Saharan ancestry. We propose that this disparity is due to selection for an enhanced Th2 response that confers resistance to …

Fizzy: Feature Subset Selection For Metagenomics., Gregory Ditzler, J Calvin Morrison, Yemin Lan, Gail L Rosen

Henry M. Rowan College of Engineering Departmental Research

BACKGROUND: Some of the current software tools for comparative metagenomics provide ecologists with the ability to investigate and explore bacterial communities using α- & β-diversity. Feature subset selection--a sub-field of machine learning--can also provide a unique insight into the differences between metagenomic or 16S phenotypes. In particular, feature subset selection methods can obtain the operational taxonomic units (OTUs), or functional features, that have a high-level of influence on the condition being studied. For example, in a previous study we have used information-theoretic feature selection to understand the differences between protein family abundances that best discriminate between age groups in the …

Settlement-Size Scaling Among Prehistoric Hunter-Gatherer Settlement Systems In The New World, W. Randall Haas, Cynthia J. Klink, Greg J. Maggard, Mark S. Aldenderfer

Anthropology Faculty Publications

Settlement size predicts extreme variation in the rates and magnitudes of many social and ecological processes in human societies. Yet, the factors that drive human settlement-size variation remain poorly understood. Size variation among economically integrated settlements tends to be heavy tailed such that the smallest settlements are extremely common and the largest settlements extremely large and rare. The upper tail of this size distribution is often formalized mathematically as a power-law function. Explanations for this scaling structure in human settlement systems tend to emphasize complex socioeconomic processes including agriculture, manufacturing, and warfare-behaviors that tend to differentially nucleate and disperse populations …

‘The Thing Is Not Knowing’: Patients' Perspectives On Surveillance Of An Indeterminate Pulmonary Nodule, Renda Soylemez Wiener, Michael K. Gould, Steven Woloshin, Lisa M. Schwartz, Jack Clark

Dartmouth Scholarship

Background: The hundreds of thousands of patients found to have a potentially malignant pulmonary nodule each year are faced with tremendous uncertainty regarding what the nodule is and how it should be evaluated.

Objective: To explore patients' responses to the detection and evaluation of a pulmonary nodule.

Effect Of A Cognitive-Behavioral Prevention Program On Depression 6 Years After Implementation Among At-Risk Adolescents: A Randomized Clinical Trial., David A Brent, Steven M. Brunwasser Phd, Steven D Hollon, V Robin Weersing, Gregory N Clarke, John F Dickerson, William R Beardslee, Tracy R G Gladstone, Giovanna Porta, Frances L Lynch, Satish Iyengar, Judy Garber

College of Science & Mathematics Departmental Research

IMPORTANCE: Adolescents whose parents have a history of depression are at risk for developing depression and functional impairment. The long-term effects of prevention programs on adolescent depression and functioning are not known.

OBJECTIVE: To determine whether a cognitive-behavioral prevention (CBP) program reduced the incidence of depressive episodes, increased depression-free days, and improved developmental competence 6 years after implementation.

DESIGN, SETTING, AND PARTICIPANTS: A 4-site randomized clinical trial compared the effect of CBP plus usual care vs usual care, through follow-up 75 months after the intervention (88% retention), with recruitment from August 2003 through February 2006 at a health maintenance organization, …

Identification And Survival Outcomes Of A Cohort Of Patients With Cancer Of Unknown Primary In Ontario, Canada., Chong S Kim, Malek B Hannouf, Sisira Sarma, George B Rodrigues, Peter K Rogan, Salaheddin M Mahmud, Eric Winquist, Muriel Brackstone, Gregory S Zaric

Epidemiology and Biostatistics Publications

BACKGROUND: Cancer of unknown primary origin (CUP) is defined by the presence of pathologically identified metastatic disease without clinical or radiological evidence of a primary tumour. Our objective was to identify incident cases of CUP in Ontario, Canada, and determine the influence of histology and sites of metastases on overall survival (OS).

MATERIAL AND METHODS: We used the Ontario Cancer Registry (OCR) and the Same-Day Surgery and Discharge Abstract Database (SDS/DAD) to identify patients diagnosed with CUP in Ontario between 1 January 2000, and 31 December 2005. Patient diagnostic information, including histology and survival data, was obtained from the OCR. …

Behavioral, Perceptual, And Neural Alterations In Sensory And Multisensory Function In Autism Spectrum Disorder., Sarah H Baum, Ryan A Stevenson, Mark T Wallace

Brain and Mind Institute Researchers' Publications

Although sensory processing challenges have been noted since the first clinical descriptions of autism, it has taken until the release of the fifth edition of the Diagnostic and Statistical Manual of Mental Disorders (DSM-5) in 2013 for sensory problems to be included as part of the core symptoms of autism spectrum disorder (ASD) in the diagnostic profile. Because sensory information forms the building blocks for higher-order social and cognitive functions, we argue that sensory processing is not only an additional piece of the puzzle, but rather a critical cornerstone for characterizing and understanding ASD. In this review we discuss what …

Functional Differences Between Statistical Learning With And Without Explicit Training., Laura J Batterink, Paul J Reber, Ken A Paller

Brain and Mind Institute Researchers' Publications

Humans are capable of rapidly extracting regularities from environmental input, a process known as statistical learning. This type of learning typically occurs automatically, through passive exposure to environmental input. The presumed function of statistical learning is to optimize processing, allowing the brain to more accurately predict and prepare for incoming input. In this study, we ask whether the function of statistical learning may be enhanced through supplementary explicit training, in which underlying regularities are explicitly taught rather than simply abstracted through exposure. Learners were randomly assigned either to an explicit group or an implicit group. All learners were exposed to …

Dual Optimization Method Of Radiofrequency And Quasistatic Field Simulations For Reduction Of Eddy Currents Generated On 7t Radiofrequency Coil Shielding., Yujuan Zhao, Tiejun Zhao, Shailesh B Raval, Narayanan Krishnamurthy, Hai Zheng, Chad T Harris, William B Handler, Blaine A Chronik, Tamer S Ibrahim

Brain and Mind Institute Researchers' Publications

PURPOSE: To optimize the design of radiofrequency (RF) shielding of transmit coils at 7T and reduce eddy currents generated on the RF shielding when imaging with rapid gradient waveforms.

METHODS: One set of a four-element, 2 × 2 Tic-Tac-Toe head coil structure was selected and constructed to study eddy currents on the RF coil shielding. The generated eddy currents were quantitatively studied in the time and frequency domains. The RF characteristics were studied using the finite difference time domain method. Five different kinds of RF shielding were tested on a 7T MRI scanner with phantoms and in vivo human subjects. …

Vascular Access: Inukshuk, Jerry Yee

Nephrology Articles

No abstract provided.

Potential Impact Of Prescribing Metformin According To Egfr Rather Than Serum Creatinine, Delphine S. Tuot, Feng Lin, Michael G. Shlipak, Vanessa Grubbs, Chi-Yuan Hsu, Jerry Yee, Vahakn Shahinian, Rajiv Saran, Sharon Saydah, Desmond E. Williams, Neil R. Powe

Nephrology Articles

OBJECTIVE: Many societies recommend using estimated glomerular filtration rate (eGFR) rather than serum creatinine (sCr) to determine metformin eligibility. We examined the potential impact of these recommendations on metformin eligibility among U.S. adults.

RESEARCH DESIGN AND METHODS: Metformin eligibility was assessed among 3,902 adults with diabetes who participated in the 1999-2010 National Health and Nutrition Examination Surveys and reported routine access to health care, using conventional sCr thresholds (eligible if

RESULTS: Among adults with sCr above conventional cutoffs, MDRD eGFR ≥45 mL/min/1.73 m(2) was most common among men (adjusted odds ratio [aOR] 33.3 [95% CI 7.4-151.5] vs. women) and non-Hispanic …

Migrated Avalon Veno-Venous Extracorporeal Membrane Oxygenation Cannula: How To Adjust Without Interruption Of Flow., Daizo Tanaka, Harrsion T. Pitcher, Nicholas C. Cavarocchi, Hitoshi Hirose

Department of Surgery Faculty Papers

The Avalon dual lumen cannula is presently the cannula of choice for veno-venous extracorporeal membrane oxygenation (VV-ECMO) via right internal jugular cannulation. This cannula establishes VV-ECMO with a single cannulation; however, it requires appropriate positioning to gain adequate oxygenation. Malposition of this cannula can cause inadequate ECMO flow, hypoxia, and structural injury. We have experienced two cases of migration: one into the hepatic vein and the other into the right ventricle. The former was repositioned using echocardiographic guidance without using a guidewire. The latter was repositioned using a guidewire from the femoral vein under fluoroscopy, without antegrade wire placement into …