Medicine and Health Sciences Commons^™

Modeling The Incubation Period Of Anthrax, Ron Brookmeyer, Elizabeth Johnson, Sarah Barry

Ron Brookmeyer

Models of the incubation period of anthrax are important to public health planners because they can be used to predict the delay before outbreaks are detected, the size of an outbreak and the duration of time that persons should remain on antibiotics to prevent disease. The difficulty is that there is little direct data about the incubation period in humans. The objective of this paper is to develop and apply models for the incubation period of anthrax. Mechanistic models that account for the biology of spore clearance and germination are developed based on a competing risks formulation. The models predict …

Up-Regulation Of Interferon-A/Apobec3g Signal Pathway Potently Inactivates Hiv-1 Infectivity In Resting Cd4-T Cells, Keyang Chen, Jialing Huang, Chune Zhang, Sophia Huang, Giuseppe Nunnari, Feng-Xiang Wang, Xiangrong Tong, Ling Gao, Kristi Nikisher, Hui Zhang

Department of Medicine Faculty Papers

Poster Presentation.

Caenorhabditis Briggsae Methods, Scott Everet Baird, Helen M. Chamberlin

Biological Sciences Faculty Publications

Caenorhabditis briggsae is being developed in parallel to C. elegans as a model system, primarily for the study of evolution. Like C. elegans, C. briggsae is a protandrous hermaphrodite and like C. elegans, its genome has been sequenced. From this point, these two model systems diverge. The development, behavior, and physiology of C. elegans have been characterized through tens of thousands of genetic and molecular studies. Genetic and molecular characterizations of C. briggsae are relatively few. Experimental resources in C. elegans include a high density recombination map that is well integrated with the genome sequence. The C. briggsae …

Hormone Effects On Fmri And Cognitive Measures Of Encoding: Importance Of Hormone Preparation, C. E. Gleason, T. W. Schmitz, T. Hess, R. L. Koscik, M. A. Trivedi, M. L. Ries, C. M. Carlsson, M. A. Sager, S. Asthana, S. C. Johnson

Brain and Mind Institute Researchers' Publications

We compared fMRI and cognitive data from nine hormone therapy (HT)-naive women with data from women exposed to either opposed conjugated equine estrogens (CEE) (n = 10) or opposed estradiol (n = 4). Exposure to either form of HT was associated with healthier fMRI response; however, CEE-exposed women exhibited poorer memory performance than either HT-naive or estradiol-exposed subjects. These preliminary findings emphasize the need to characterize differential neural effects of various HTs. ©2006AAN Enterprises, Inc.

Tyrosine Phosphorylation Of Villin: Effects On Actin Dynamics, Cell Morphology And Cell Migration, Alok Tomar

Theses and Dissertations (ETD)

Cell migration is a key aspect of many normal and abnormal biological processes, including embryonic development, defense against infections, wound healing, and tumor cell metastasis. In this study we demonstrate that an epithelial cell actin-binding protein, villin, plays a crucial role in the process of cell migration. Overexpression of villin in doxycyline-regulated HeLa Tet-off and MDCK Tet-off cells enhanced cell migration. We further demonstrate that tyrosine phosphorylation of villin by c-src is required for villin-induced cell migration. Previously, we identified four tyrosine phosphorylation sites in the amino-terminal domain of villin. I further identified six new sites in the carboxylterminal region …

Wavelet-Based Functional Mixed Models To Characterize Population Heterogeneity In Accelerometer Profiles: A Case Study. , Jeffrey S. Morris, Cassandra Arroyo, Brent A. Coull, Louise M. Ryan, Steven L. Gortmaker

Jeffrey S. Morris

We present a case study illustrating the challenges of analyzing accelerometer data taken from a sample of children participating in an intervention study designed to increase physical activity. An accelerometer is a small device worn on the hip that records the minute-by-minute activity levels of the child throughout the day for each day it is worn. The resulting data are irregular functions characterized by many peaks representing short bursts of intense activity. We model these data using the wavelet-based functional mixed model. This approach incorporates multiple fixed effects and random effect functions of arbitrary form, the estimates of which are …

Alternative Probeset Definitions For Combining Microarray Data Across Studies Using Different Versions Of Affymetrix Oligonucleotide Arrays, Jeffrey S. Morris, Chunlei Wu, Kevin R. Coombes, Keith A. Baggerly, Jing Wang, Li Zhang

Jeffrey S. Morris

Many published microarray studies have small to moderate sample sizes, and thus have low statistical power to detect significant relationships between gene expression levels and outcomes of interest. By pooling data across multiple studies, however, we can gain power, enabling us to detect new relationships. This type of pooling is complicated by the fact that gene expression measurements from different microarray platforms are not directly comparable. In this chapter, we discuss two methods for combining information across different versions of Affymetrix oligonucleotide arrays. Each involves a new approach for combining probes on the array into probesets. The first approach involves …

Identifying Important Explanatory Variables For Time-Varying Outcomes., Oliver Bembom, Maya L. Petersen, Mark J. Van Der Laan

Maya Petersen

This chapter describes a systematic and targeted approach for estimating the impact of each of a large number of baseline covariates on an outcome that is measured repeatedly over time. These variable importance estimates can be adjusted for a user-specified set of confounders and lend themselves in a straightforward way to obtaining confidence intervals and p-values. Hence, they can in particular be used to identify a subset of baseline covariates that are the most important explanatory variables for the time-varying outcome of interest. We illustrate the methodology in a data analysis aimed at finding mutations of the human immunodeficiency virus …

Identifying Important Explanatory Variables For Time-Varying Outcomes., Oliver Bembom, Maya L. Petersen, Mark J. Van Der Laan

Oliver Bembom

This chapter describes a systematic and targeted approach for estimating the impact of each of a large number of baseline covariates on an outcome that is measured repeatedly over time. These variable importance estimates can be adjusted for a user-specified set of confounders and lend themselves in a straightforward way to obtaining confidence intervals and p-values. Hence, they can in particular be used to identify a subset of baseline covariates that are the most important explanatory variables for the time-varying outcome of interest. We illustrate the methodology in a data analysis aimed at finding mutations of the human immunodeficiency virus …

Androgen-Regulated Formation And Degradation Of Gap Junctions In Androgen-Responsive Human Prostate Cancer Cells., Shalini Mitra, Lakshmanan Annamalai, Souvik Chakraborty, Kristen E. Johnson, Xiao-Hong Song, Surinder K. Batra, Parmender P. Mehta

Journal Articles: Biochemistry & Molecular Biology

The constituent proteins of gap junctions, called connexins (Cxs), have a short half-life. Despite this, the physiological stimuli that control the assembly of Cxs into gap junctions and their degradation have remained poorly understood. We show here that in androgen-responsive human prostate cancer cells, androgens control the expression level of Cx32-and hence the extent of gap junction formation-post-translationally. In the absence of androgens, a major fraction of Cx32 is degraded presumably by endoplasmic reticulum-associated degradation, whereas in their presence, this fraction is rescued from degradation. We also show that Cx32 and Cx43 degrade by a similar mechanism. Thus, androgens regulate …

Narcotic Analgesics For Acute Migraine In The Emergency Room: Are We Meeting Headache Societies' Guidelines?, Mohammad Wasay, Khawaja Slaman Zaki, Saqib Uddin Khan, Rifat Rehmani

Department of Emergency Medicine

We analysed 161 patients with acute migraine in our emergency room (ER) to identify the use of narcotic analgesics as first-line treatment. Twenty-four percent of patients were treated with opioid analgesics and 76% patients were treated with non-opioid analgesics. Pain was completely relieved in 100 (62%) patients, partially relieved in 50 (31%) patients and was not relieved in 11 (7%) patients at the time of discharge. Pain relief was not related to the use of opioids vs. non-opioids. The treatment of acute migraine in our ER is in line with the guidelines of the Headache Societies and needs further improvement.

Appl1 Associates With Trka And Gipc1 And Is Required For Nerve Growth Factor-Mediated Signal Transduction, D. C. Lin, C. Quevedo, N. E. Brewer, A. Bell, J. R. Testa, Mark L. Grimes, F. D. Miller, D. R. Kaplan

Biomedical and Pharmaceutical Sciences Faculty Publications

The neurotrophin receptor TrkA plays critical roles in the nervous system by recruiting signaling molecules that activate pathways required for the growth and survival of neurons. Here, we report APPL1 as a TrkA-associated protein. APPL1 and TrkA coirnmunoprecipitated in sympathetic neurons. We have identified two routes through which this association can occur. APPL1 was isolated as a binding partner for the TrkA-interacting protein GIPC1 from rat brain lysate by mass spectrometry. The PDZ domain of GIPC1 directly engaged the C-terminal sequence of APPL1. This interaction provides a means through which APPL1 may be recruited to TrkA. In addition, the APPL1 …

Combined Effects Of Aldehyde Dehydrogenase Variants And Maternal Mitochondrial Genes On Alcohol Consumption, Yedy Israel, Maria E. Quintanilla, Amalia Sapag, Lutske Tampier

Department of Pathology, Anatomy, and Cell Biology Faculty Papers

Two lines of rats bred to differ in their voluntary alcohol consumption — the alcohol-abstaining UChA rats and the alcohol-drinking UChB rats — differ in how effectively toxic acetaldehyde is removed during alcohol metabolism. UChB animals carry efficient variants of the aldehyde dehydrogenase 2 (ALDH2) genes and have active mitochondria, resulting in fast removal of acetaldehyde. UChA animals, in contrast, carry less efficient ALDH2 variants and less active mitochondria, which result in transient elevations of acetaldehyde levels after alcohol ingestion. Cross-breeding studies have demonstrated that the presence of active mitochondria inherited from UChB females can fully abolish the reduction of …

Chemoprevention Of Breast Cancer For Women At Hgh Risk, Kathryn Chan, Gloria J. Morris

Department of Medicine Faculty Papers

Breast cancer remains the second most common cause of cancer death in the United States. Several studies have identified cohorts of women at higher than average risk to develop this disease. These are women who are exposed to high levels of endogenous or exogenous estrogens, those with a family history of breast cancer, and those who harbor benign breast disease or genetic mutations that predispose to breast cancer. In this population group, adapting a chemoprevention strategy to decrease the risk of developing overt disease is a strong consideration. To this end, tamoxifen is the most accepted agent to date. This …

An In Vitro Model Of Ovarian Cancer: Studying The Effects Of Talc And Pycnogenol®, Amber Renée Buz'zard

Loma Linda University Electronic Theses, Dissertations & Projects

Ovarian cancer is the sixth most common cancer and accounts for more deaths than any other cancer of the female reproductive system. The American Cancer Society has suggested that poor diet, talc and industrial pollutants may increase the risk of developing ovarian cancer. Talc is ubiquitous and concern is raised about its safety, role as a possible carcinogen and known ability to cause irritation and inflammation. Due to the silent nature of ovarian cancer, chemoprevention is a high priority. The most useful chemopreventive compounds will inhibit, delay or reverse carcinogenesis, and can be taken for long periods of time with …

Clarification Of Basal Relationships In Rubus (Rosaceae) And The Origin Of Rubus Chamaemorus, Karen Michael

Masters Theses & Specialist Projects

Determination of phylogenetic relationships among ancestral species of Rubus has been elusive. Most Rubus species (including blackberries and raspberries), representing nine of the 12 subgenera, occur in a large, well supported clade named 'A' for reference). The remaining nine species are excluded from this group and represent three subgenera: subg. Anoplobatus (R. bartonianus, R. deliciosus, R. neomexicanus, R. odoratus, R. parviflorus, R. trilobus), subg. Chamaemorus (R. chamaemorus), and subg. Dalibarda (R. lasiococcus, R.pedatus). In addition, Rubus dalibarda L. is often treated in its own monotypic genus as Dalibarda repens L. Phylogenetic analyses of DNA sequence data from chloroplast regions and …

Biomolecular Tuning Of Electronic Transport Properties Of Carbon Nanotubes Via Antibody Functionalization, Kasif Teker, Dr. Eric Wickstrom, Balaji Panchapakesan

Department of Biochemistry and Molecular Biology Faculty Papers

Carbon nanotubes (CNTs) are remarkable solidstate nanomaterials due to their unique electrical and mechanical properties. The electronic properties of nanotubes combined with biological molecules such as proteins could make miniature devices for biological sensing applications. In this paper, the noncovalent interaction of single-wall CNTs with antibodies is presented for its potential applications for detecting overexpressed cell surface receptors in breast cancer cells. The degree of binding of antibodies on CNTs was found to be more than 80% for an extended sampling area by confocal microscopy. The key to achieve such high degree of functionalization is due to the separation of …

Organochlorine Levels In Seawater And Sediment From The Florida Gulf Coast, If Present, Are Low. , Richard B. Philp

Richard B. Philp

Seawater and sediment from the Florida panhandle coast were assayed for a panel of 28 organochlorine insecticides and PCBs. No samples exeeded the detection limits of the analytical technique, which were well below levels reported for other ocean locales. Organochlorine levels in this area of the Gulf must be very low. This does not preclude their biomagnificatioon up the food web.

Modeling An Outbreak Of Anthrax, Ron Brookmeyer

Ron Brookmeyer

Introduction

On October 2, 2001 a sixty-three-year-old Florida man who worked as a photo editor at a media publishing company was admitted to an emergency department complaining of nausea, vomiting, and fever. His symptoms began four days earlier on a recreational trip to North Carolina. The man died shortly thereafter. An astute clinician quickly made the surprising diagnosis of inhalational anthrax, which is a serious and deadly disease. The diagnosis was surprising because inhalational anthrax is extremely rare; only 18 cases were reported in the United States between 1900 and 1978. Public health officials at first believed that the Florida …

Nucleolin Is Required For Rna Polymerase I Transcription In Vivo, Brendan Rickards, S. Flint, Michael D. Cole, Gary Leroy

Dartmouth Scholarship

Eukaryotic genomes are packaged with histones and accessory proteins in the form of chromatin. RNA polymerases and their accessory proteins are sufficient for transcription of naked DNA, but not of chromatin, templates in vitro. In this study, we purified and identified nucleolin as a protein that allows RNA polymerase II to transcribe nucleosomal templates in vitro. As immunofluorescence confirmed that nucleolin localizes primarily to nucleoli with RNA polymerase I, we demonstrated that nucleolin allows RNA polymerase I transcription of chromatin templates in vitro. The results of chromatin immunoprecipitation experiments established that nucleolin is associated with chromatin containing rRNA genes transcribed …

Donor Tricuspid Annuloplasty During Orthotopic Heart Transplantation: Long-Term Results Of A Prospective Controlled Study, Valluvan Jeevanandum, Hyde Russell, Paul Mather, Satoshi Furukawa, Allen Anderson, Jaishankar Raman

Department of Medicine Faculty Papers

Background: Development of tricuspid regurgitation after orthotopic heart transplantation can cause heart failure along with renal and hepatic impairment and portends a poor prognosis. If tricuspid regurgitation causes significant symptoms, tricuspid valve repair or replacement is often required. This study was designed to study the effects of prophylactic tricuspid valve annuloplasty (TVA) during orthotopic heart transplantation on long-term survival, renal function, and amount of tricuspid regurgitation.

Methods: Between April 1997 and March 1998, 60 patients (aged 18 to 70 years; 22 female) randomly received either standard bicaval orthotopic heart transplantation (group STD; n = 30) or bicaval orthotopic …

Screening Assay For Inhibitors Of Severe Acute Respiratory Syndrome (Sars) Using Seldi-Tof Mass Spectrometry, Khalid M. Elased, Mariana Morris

Pharmacology and Toxicology Faculty Publications

Mass spectrometric methods directed to screening libraries of compounds for agents that inhibit entry of Severe Acute Respiratory Syndrome (SARS) coronavirus (CoV) into cells are provided, along with methods for comparatively evaluating inhibitors of the SARS CoV.

Multiple Domains In Siz Sumo Ligases Contribute To Substrate Selectivity., Alison Reindle, Irina Belichenko, Gwendolyn R Bylebyl, Xiaole L Chen, Nishant Gandhi, Erica S Johnson

Department of Biochemistry and Molecular Biology Faculty Papers

Saccharomyces cerevisiae contains two Siz/PIAS SUMO E3 ligases, Siz1 and Siz2/Nfi1, and one other known ligase, Mms21. Although ubiquitin ligases are highly substrate-specific, the degree to which SUMO ligases target distinct sets of substrates is unknown. Here we show that although Siz1 and Siz2 each have unique substrates in vivo, sumoylation of many substrates can be stimulated by either protein. Furthermore, in the absence of both Siz proteins, many of the same substrates are still sumoylated at low levels. Some of this residual sumoylation depends on MMS21. Siz1 targets its unique substrates through at least two distinct domains. Sumoylation of …

Soluble Amyloid Oligomers Increase Bilayer Conductance By Altering Dielectric Structure, Yuri Sokolov, J. Ashot Kozak, Rakez Kayed, Alexandr Chanturiya, Charles G. Glabe, James E. Hall

Neuroscience, Cell Biology & Physiology Faculty Publications

The amyloid hypothesis of Alzheimer's toxicity has undergone a resurgence with increasing evidence that it is not amyloid fibrils but a smaller oligomeric species that produces the deleterious results. In this paper we address the mechanism of this toxicity. Only oligomers increase the conductance of lipid bilayers and patch-clamped mammalian cells, producing almost identical current-voltage curves in both preparations. Oligomers increase the conductance of the bare bilayer, the cation conductance induced by nonactin, and the anion conductance induced by tetraphenyl borate. Negative charge reduces the sensitivity of the membrane to amyloid, but cholesterol has little effect. In contrast, the area …

Antimicrobial Effects Of Liquid Anesthetic Isoflurane On Candida Albicans, Viachaslau M. Barodka, Edward Acheampong, Garry Powell, Ludmilla Lobach, David A. Logan, Zahida Parveen, Valerie Armstead, Muhammad Mukhtar

Department of Medicine Faculty Papers

Candida albicans is a dimorphic fungus that can grow in yeast morphology or hyphal form depending on the surrounding environment. This ubiquitous fungus is present in skin and mucus membranes as a potential pathogen that under opportunistic conditions causes a series of systemic and superficial infections known as candidiasis, moniliasis or simply candidiasis. There has been a steady increase in the prevalence of candidiasis that is expressed in more virulent forms of infection. Although candidiasis is commonly manifested as mucocutaneous disease, life-threatening systemic invasion by this fungus can occur in every part of the body. The severity of candidal infections …

Cdx4 Dysregulates Hox Gene Expression And Generates Acute Myeloid Leukemia Alone And In Cooperation With Meis1a In A Murine Model, Dimple Bansal, Claudia Scholl, Stefan Frohling, Elizabeth Mcdowell, Benjamin H. Lee, Konstanze Döhner, Patricia Ernst

Dartmouth Scholarship

HOX genes have emerged as critical effectors of leukemogenesis, but the mechanisms that regulate their expression in leukemia are not well understood. Recent data suggest that the caudal homeobox transcription factors CDX1, CDX2, and CDX4, developmental regulators of HOX gene expression, may contribute to HOX gene dysregulation in leukemia. We report here that CDX4 is expressed normally in early hematopoietic progenitors and is expressed aberrantly in approximately 25% of acute myeloid leukemia (AML) patient samples. Cdx4 regulates Hox gene expression in the adult murine hematopoietic system and dysregulates Hox genes that are implicated in leukemogenesis. Furthermore, bone marrow progenitors that …

Foreign Body In The Esophagus: A Review, Omer Ashraf

Medical College Documents

Foreign body in the esophagus is a common emergency presentation. The approach towards a patient with a foreign body in the esophagus comprises a thorough history and systematic examination followed by relevant investigations. However, there is considerable debate over the most appropriate treatment option for such patients. This review aims to develop a comprehensive approach towards patients presenting with foreign body ingestion by developing clinical practice guidelines. These guidelines address not only the initial evaluation of the patient but also the various management alternatives and their advantages, limitations and applicability in various scenarios, based upon a review of the literature.

Sub-Typing Of Prrsv Isolates By Means Of Measurement Of Cross-Neutralization Reactions, Fernando A. Osorio

School of Veterinary and Biomedical Sciences: Faculty Publications

The degree of similitude or closeness between two different isolates or strains of PRRSV is very important for deciding which strains should be used for immunization, by either vaccinating with commercial vaccines or attempting to stabilize a herd with planned wt PRRSV infection. As previously known for certain important viral diseases, such as in Foot and Mouth Disease, the reciprocal (cross-) neutralization titers between two strains may be of utmost importance to establish the degree of similarity or difference between these. There is currently a void of methods that would allow distinguishing or grouping strains of PRRSV in a manner …

Measuring The Development Of Executive Control With The Shape School, K. A. Espy, R. B. Bull, J Martin, W. Stroup

Developmental Cognitive Neuroscience Laboratory: Faculty and Staff Publications

Although several neurodevelopmental and psychiatric disorders can emerge during the preschool period, there are comparatively few instruments to assess executive control. Evidence for validity of the Shape School (K. A. Espy, 1997) was examined in a sample of 219 typically developing young children. There was good evidence for validity, as Shape School performance variables were interrelated and were associated to other criterion measures considered to measure aspects of executive control. Also suggesting validity, the Shape School variables varied as a function of whether the task demands (a) were executive, (b) required inhibition of a prepotent response or context-controlled selection among …

Working Memory, Executive Functioning, And Children's Mathematics, R. Bull, K. A. Espy

Developmental Cognitive Neuroscience Laboratory: Faculty and Staff Publications

Approximately 3-6% of school-age children are estimated to have mathematics difficulties (Badian, 1983; Gross-Tsur, Manor, & Shalev, 1996; Kosc, 1974, Lewis, Hitch, & Walker, 1994). There are many more children in regular school classrooms who struggle with mathematics but whose performance is not considered sufficiently poor to be classified as meriting a specific disability in mathematics. Specific mathematic learning disability (MLD) is defined in psychiatric and educational venues as a large discrepancy between mathematics ability compared to reading and general intellectual ability, although the size of the discrepancy required varies. To further complicate matters, mathematic difficulties are associated with other …