Medical Specialties Commons^™

Chloride Equilibrium Potential In Salamander Cones., Wallace B. Thoreson, Eric J. Bryson

Journal Articles: Ophthalmology

BACKGROUND: GABAergic inhibition and effects of intracellular chloride ions on calcium channel activity have been proposed to regulate neurotransmission from photoreceptors. To assess the impact of these and other chloride-dependent mechanisms on release from cones, the chloride equilibrium potential (ECl) was determined in red-sensitive, large single cones from the tiger salamander retinal slice.

RESULTS: Whole cell recordings were done using gramicidin perforated patch techniques to maintain endogenous Cl- levels. Membrane potentials were corrected for liquid junction potentials. Cone resting potentials were found to average -46 mV. To measure ECl, we applied long depolarizing steps to activate the calcium-activated chloride current …

Distinct Gene Expression Profiles In Different B-Cell Compartments In Human Peripheral Lymphoid Organs., Yulei Shen, Javeed Iqbal, Li Xiao, Ryan C. Lynch, Andreas Rosenwald, Louis M. Staudt, Simon Sherman, Karen Dybkaer, Guimei Zhou, James D. Eudy, Jan Delabie, Timothy W. Mckeithan, Wing C. Chan

Journal Articles: Eppley Institute

BACKGROUND: There are three major B-cell compartments in peripheral lymphoid organs: the germinal center (GC), the mantle zone (MNZ) and the marginal zone (MGZ). Unique sets of B-cells reside in these compartments, and they have specific functional roles in humoral immune response. MNZ B cells are naive cells in a quiescent state and may participate in GC reactions upon proper stimulation. The adult splenic MGZ contains mostly memory B cells and is also known to provide a rapid response to particulate antigens. The GC B-cells proliferate rapidly and undergo selection and affinity maturation. The B-cell maturational process is accompanied by …

Immunopathogenesis Of Brain Abscess., Tammy Kielian

Journal Articles: Pathology and Microbiology

Brain abscess represents a significant medical problem despite recent advances made in detection and therapy. Due to the emergence of multi-drug resistant strains and the ubiquitous nature of bacteria, the occurrence of brain abscess is likely to persist. Our laboratory has developed a mouse experimental brain abscess model allowing for the identification of key mediators in the CNS anti-bacterial immune response through the use of cytokine and chemokine knockout mice. Studies of primary microglia and astrocytes from neonatal mice have revealed that S. aureus, one of the main etiologic agents of brain abscess in humans, is a potent stimulus for …

Molecular Dynamics Simulations Of The O-Glycosylated 21-Residue Muc1 Peptides, A. Rubinstein, L. Kinarsky, S. Sherman

Journal Articles: Eppley Institute

The conformational propensities of the 21-residue peptide and its Oglycosylated analogs were studied by molecular dynamics (MD) simulations. This polypeptide motif comprises the tandem repeat of the human mucin (MUC1) protein core that is differently glycosylated in normal and cancer cells. To evaluate the structural effects of O-glycosylation on the polypeptide backbone, conformations of the nonglycosylated peptide and its glycosylated analogs were monitored during the 1 ns MD simulations. Radius gyration for whole peptide and its fragments, as well as root-mean-square-deviation between coordinate sets of the backbone atoms of starting structures and generated structures, were calculated. It was shown that …

Nmr-Based Structural Studies Of The Glycosylated Muc1 Tandem Repeat Peptide, G. Suryanarayanan, P. A. Keifer, G. Wang, L. Kinarsky, M. A. Hollingsworth, S. Sherman

Journal Articles: Eppley Institute

MUC1 is a glycoprotein that plays an important role in cancer pathogenesis. In order to study the effect of glycosylation on the conformational propensities of the tandem repeat domain of MUC1, we have determined the structure of the MUC1 tandem repeat peptide AHGVTSAPDTRPAPGSTAPP, O-glycosylated with the trisaccharide (α-Glc-1,4-β-Glc-1,4-α-GalNAc-) at Thr5. This glycopeptide was synthesized to model a heavily Oglycosylated threonine residue in the tandem repeat domain. The NMR experiments used in this study included TOCSY, NOESY, ROESY, DQF-COSY, HSQC and 1D NMR. The peak volumes determined using the program SPARKY were converted into distance constraints using the program CALIBA. The …

Albumin Enhanced Morphometric Image Analysis In Cll., Matthew A. Lunning, Vincent E. Zenger, Ricardo Dreyfuss, Maryalice Stetler-Stevenson, Margaret E. Rick, Therese A. White, Wyndham H. Wilson, Gerald E. Marti

Journal Articles: Oncology and Hematology

BACKGROUND: The heterogeneity of lymphocytes from patients with chronic lymphocytic leukemia (CLL) and blood film artifacts make morphologic subclassification of this disease difficult.

METHODS: We reviewed paired blood films prepared from ethylene-diamine-tetraacetic acid (ETDA) samples with and without bovine serum albumin (BSA) from 82 CLL patients. Group 1 adhered to NCCLS specifications for the preparations of EDTA blood films. Group 2 consisted of blood films containing EDTA and a 1:12 dilution of 22% BSA. Eight patients were selected for digital photomicroscopy and statistical analysis. Approximately 100 lymphocytes from each slide were digitally captured.

RESULTS: The mean cell area +/- standard …

Requirement For The Betai And Betaiv Tubulin Isotypes In Mammalian Cilia., Heather C Jensen-Smith, Richard F Ludueña, Richard Hallworth

Journal Articles: Eppley Institute

Nielsen et al., [2001: Curr Biol 11:529-533], based on studies in Drosophila, have proposed that beta tubulin in axonemal microtubules must contain a specific acidic seven amino acid sequence in its carboxyl terminus. In mammals, the two betaIV isotypes (betaIVa and betaIVb) contain that sequence. In order to test the application of this hypothesis to mammals, we have examined the expression of beta tubulin isotypes in four different ciliated tissues (trachea, ependyma, uterine tube, and testis) using isotype-specific antibodies and indirect immunofluorescence. We find that betaIV tubulin is present in all ciliated cell types examined, but so is betaI tubulin. …

Selective Expression Of Beta Tubulin Isotypes In Gerbil Vestibular Sensory Epithelia And Neurons, Brian Perry, Heather Jensen Smith, Richard F. Ludueña, Richard Hallworth

Journal Articles: Eppley Institute

The seven mammalian isotypes of beta tubulin are strikingly similar in amino acid sequence. The differences in isotypic sequence, although small, are nonetheless conserved in evolution, which suggests that they may confer distinct functional roles. If so, such roles should be reflected in the selective expression of isotypes by cell type, or even in the sorting of isotypes to within-cell pools. Hair cells of the vestibular sensory epithelia each possess a kinocilium, a microtubule-based organelle that could represent a distinct microtubule compartment, separate from the extensive microtubule network in the soma. The afferent neurons that innervate the vestibular sensory epithelia …

Cell Type-Specific Reduction Of Beta Tubulin Isotypes Synthesized In The Developing Gerbil Organ Of Corti, Heather Jensen Smith, Jonquille Eley, Peter S. Steyger, Richard F. Ludueña, Richard Hallworth

Journal Articles: Eppley Institute

There are seven isotypic forms of the microtubule protein beta tubulin in mammals, but not all isotypes are synthesized in every cell type. In the adult organ of Corti, each of the five major cell types synthesizes a different subset of isotypes. Inner hair cells synthesize only betaI and betaII tubulin, while outer hair cells make betaI and betaIV tubulin. Only betaII and betaIV tubulin are found in inner and outer pillar cells, while betaI, betaII, and betaIV tubulin are present in Deiters cells, and betaI, betaII and betaIII tubulin are found in organ of Corti dendrites. During post-natal organ …

Platelets Stimulate Fibroblast-Mediated Contraction Of Collagen Gels, Ulrika Zagai, Karin Fredriksson, Stephen I. Rennard, Joachim Lundahl, C. Magnus Sköld

Journal Articles: Pulmonary & Critical Care Med

BACKGROUND: Platelets are thought to play a role in a variety of inflammatory conditions in the lung, some of which may lead to fibrosis. In the current study we tested the hypothesis that whole platelets and platelet lysate can mediate remodelling of extracellular matrix in vitro by affecting fibroblast-mediated contraction of a collagen gel. We also sought to determine to what extent platelet-derived growth factor (PDGF) and transforming growth factor-beta (TGF-beta) contribute to this effect.

METHODS: Washed platelets, isolated from healthy blood donors, and platelet lysate (freezing and thawing), were cast together with human lung fibroblasts in three-dimensional collagen gels. …

Role Of Disulphide Bond Formation In Folding, Secretion, And Assembly Of Human Chorionic Gonadotropin Subunits., Elliott Bedows, Ryan J. Darling, Jason A. Wilken, Simon Sherman

Journal Articles: Eppley Institute

Ability of a glycoprotein hormone to fold and assemble correctly is an essential requirement for the attainment of its biological activity . Cells have a quality control system to assure that when proteins of the endoplasmic reticulum mi sfold or fail to assemble correctly they do not exit the cell. But human chorionic gonadotropin (hCG) is an exception to this rule as is illustrated by the following observations. First, both hCG subunits are secreted efficiently as unassembled monomers. Second, some mis(un)folded forms of hCG-β can be efficiently secreted from cells that do not facilitate the secretion of other misfolded proteins. …

Differential Synthesis Of Beta-Tubulin Isotypes In Gerbil Nasal Epithelia, Karen Woo, Heather Jensen Smith, Richard F. Ludueña, Richard Hallworth

Journal Articles: Eppley Institute

Compartmentalization of beta-tubulin isotypes within cells according to function was examined in gerbil olfactory and respiratory epithelia by using specific antibodies to four beta-tubulin isotypes (beta(I), beta(II), beta(III), and beta(IV)). Isotype synthesis was cell-type-specific, but the localization of the isotypes was not compartmentalized. All four isotypes were found in the cilia, dendrites, somata, and axons of olfactory neurons. Only two isotypes (beta(I) and beta(IV)) were present in the cilia of nasal respiratory epithelial cells. The beta(IV) isotype, thought to be an essential component of cilia, was present in olfactory neurons and respiratory epithelial cells, which are ciliated, but was not …

An Open-Label Trial Of Tomoxetine In Pediatric Attention Deficit Hyperactivity Disorder., Christopher J. Kratochvil, Daryl Bohac, Martin Harrington, Natalie Baker, Diane E. May, William J. Burke

Journal Articles: Psychiatry

OBJECTIVE: To collect pilot data assessing the safety, tolerability, and efficacy of tomoxetine, a nonstimulant norepinephrine enhancer, in pediatric attention deficit hyperactivity disorder (ADHD).

METHODS: An open-label trial of tomoxetine in pediatric ADHD was conducted as part of a multisite clinical trial. Following a baseline assessment, an ascending dose titration was completed during 10 weekly visits.

RESULTS: Ten subjects were enrolled at baseline, with eight completing the study. Seven of the eight remaining subjects met efficacy criteria. Significant decreases in symptom severity ratings by parents and study investigators were found. The medication was well tolerated, with transient appetite suppression the …

Repair Of The Airway Epithelium: Potential Opportunities For Therapeutic Intervention In Airway Disease, Stephen I. Rennard

Journal Articles: Pulmonary & Critical Care Med

The epithelium of the airway has considerable capacity to undergo repair. These repair processes are responsible for maintaining and restoring function after injury of the airways, which likely occurs often as a result of infectious, toxic or other exposures. However, repair processes need not be fully effective. Inadequate repair can take a number of forms and may result in metaplasia, hyperplasia or fibrotic scarring. It is likely that repair processes that lead to tissue disruption play an important role in the chronic airways diseases, such as asthma and bronchitis. Through delineation of these processes, it may become feasible to target …

Efficient Vasoactive Intestinal Polypeptide Hydrolyzing Autoantibody Light Chains Selected By Phage Display, Sonia Tyutyulkova, Qing-Sheng Gao, Austin Thompson, Stephen I. Rennard, Sudhir Paul

Journal Articles: Pulmonary & Critical Care Med

An immunoglobulin light chain (L chain) library derived from the peripheral blood lymphocytes of a patient with asthma was cloned into a phagemid vector. Phage particles displaying L chains capable of binding vasoactive intestinal polypeptide (VIP) were isolated by affinity chromatography. Two VIP binding L chains were expressed in Escherichia coli in soluble form and purified to electrophoretic homogeneity by metal chelating and protein L affinity chromatography. Both L chains catalyzed the hydrolysis of [tyr10-125I]VIP substrate. The catalytic activity eluted at the molecular mass of the monomer form of the L chain (28 kDa) from a gel filtration column. The …

Removal Of Extracellular Chloride Suppresses Transmitter Release From Photoreceptor Terminals In The Mudpuppy Retina., Wallace B. Thoreson, R . F. Miller

Journal Articles: Ophthalmology

Removal of extracellular Cl- has been shown to suppress light-evoked voltage responses of ON bipolar and horizontal cells, but not photoreceptors or OFF bipolar cells, in the amphibian retina. A substantial amount of experimental evidence has demonstrated that the photoreceptor transmitter, L-glutamate, activates cation, not Cl-, channels in these cells. The mechanism for Cl-free effects was therefore reexamined in a superfused retinal slice preparation from the mudpuppy (Necturus maculosus) using whole-cell voltage and current clamp techniques. In a Cl-free medium, light-evoked currents were maintained in rod and cone photoreceptors but suppressed in horizontal, ON bipolar, and OFF bipolar cells. Changes …

Analysis Of The Effects Of Overexpression Of Metallothionein-I In Transgenic Mice On The Reproductive Toxicology Of Cadmium., T Dalton, Kai Fu, G C Enders, R D Palmiter, G K Andrews

Journal Articles: Pathology and Microbiology

Exposure to low levels of cadmium reduces fertility. In male mice spermatogenesis is highly sensitive to cadmium, whereas in females the peri-implantation period of pregnancy is sensitive. To examine the potential roles of the cadmium-binding protein, metallothionein (MT), in the reproductive toxicology of cadmium, we examined a transgenic mouse strain that overexpresses metallothionein-I (MT-I). These mice had dramatically increased steady-state levels of MT-I mRNA and MT in the testes and in the female reproductive tract during the peri-implantation period of pregnancy, and this overexpression occurred in a cell-specific and temporally regulated manner similar to that of the endogenous MT-I gene. …

Actions Of (1s,3r)-1-Aminocyclopentane-1,3-Dicarboxylic Acid (1s,3r-Acpd) In Retinal On Bipolar Cells Indicate That It Is An Agonist At L-Ap4 Receptors., Wallace B. Thoreson, R. F. Miller

Journal Articles: Ophthalmology

Metabotropic glutamate receptors (mGluRs) include receptors sensitive to L-2-amino-4-phosphonobutyrate (L-AP4) and 1S,3R-1-aminocyclopentane-1,3-dicarboxylic acid (1S,3R-ACPD). To determine whether 1S,3R-ACPD is an agonist at retinal L-AP4 receptors, whole cell voltage clamp recordings were obtained from mudpuppy ON bipolar cells in a superfused retinal slice and L-AP4 and 1S,3R-ACPD were bath applied. Both compounds evoked similar outward currents which reversed near 0 mV and were accompanied by an increased input resistance. Responses to both agonists washed out in parallel suggesting they act through the same second messenger pathway(s). Inhibitors of cGMP-PDE activity suppressed responses to both L-AP4 and 1SR,3RS-ACPD, suggesting that both compounds …

Oral Assessment Guide, June Eilers, Ann Berger

Guides and Handouts: College of Nursing

The Oral Assessment Guide (OAG) can be used by the clinician to evaluate changes in the oral cavity. The OAG is comprised of eight categories of mucositis assessment of the mouth on a scale of 1 to 3, with “1” indicating normal and “3” indicating breakdown or loss of function. The OAG has been validated and is reliable in the current published format. Permission is granted for use in the current format. Any modifications will require new testing for validity and reliability. The OAG has been widely used in cancer and other populations and published in professional journals and books.