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The Structure Of Tumor Necrosis Factor-Α At 2.6 Å Resolution. Implications For Receptor Binding, M. J. Eck, S. R. Sprang

Biological Sciences Faculty Publications

The three-dimensional structure of tumor necrosis factor (TNF-α), a protein hormone secreted by macrophages, has been determined at 2.6 Å resolution by x-ray crystallography. Phases were determined by multiple isomorphous replacement using data collected from five heavy atom derivatives. The multiple isomorphous replacement phases were further improved by real space symmetry averaging, exploiting the non-crystallographic 3-fold symmetry of the TNF-α trimer. An atomic model corresponding to the known amino acid sequence of TNF-α was readily built into the electron density map calculated with these improved phases. The 17,350-dalton monomer forms an elongated, antiparallel β-pleated sheet sandwich with a 'jelly-roll' topology. …

Vegetation And Environment In An Adjacent Post Oak Flatwoods And Barrens In Indiana, Rebecca W. Dolan, Eric S. Menges

Scholarship and Professional Work - LAS

To compare adjacent post oak flatwoods and barrens communities in south-western Indiana, we used vegetational, environmental and fire history data in multivariate analyses. Barrens had greater dominance by post oak and lower tree species richness, but variation in tree species composition was not strongly related to soil moisture, litter depth or other environmental gradients measured. Tree growth has been slow and variable, with little difference between the barrens and flatwoods. Barrens and flatwoods differ in herb species composition, but with considerable overlap. In the barrens, herbaceous vegetation composition was correlated with tree basal area, litter depth and soil moisture; in …

Review: 'Deepening Christian Life: Integrating Faith And Maturity', William P. Roberts

Theology and Religious Studies Faculty Publications

No abstract provided.

Distribution Patterns Of Hp1, A Heterochromatin-Associated Nonhistone Chromosomal Protein Of Drosophila, T James, J Eissenberg, C Craig, V Dietrich, A Hobson, Sarah C.R. Elgin

Biology Faculty Research

We have previously reported the identification of a nonhistone chromosomal protein (nhcp-19; now called HP1) preferentially associated with the heterochromatin of Drosophila melanogaster. A detailed study of the HP1 distribution pattern on polytene chromosomes by immunofluorescent staining, using monoclonal antibody C1A9, has been carried out. The results indicate that this protein is found within the centric beta-heterochromatin, in cytological regions 31, 41 and 80, and throughout polytene chromosome 4. Staining of telomeres is frequently observed, those of chromosome arms 2R and 3R and the X chromosome being the most conspicuous. Analysis of a fourth chromosome insertional translocation T(3;4)f/In(3L)P confirms an …

Changes In Caloric Content As A Result Of Sub-Lethal Stress In Neanthes Virens (Sars), Phyllis J. Friello

Biological Sciences Theses & Dissertations

Neanthes virens were subjected to a toxicity test with 1.8, 3.4, 6.7 and 11.0 mg/1 Cd²⁺. Worms were withdrawn on Days 1, 4, 7, 10 and 14 from each of five replicate tanks and their caloric content determined by bomb calorimetry. Analyses of variance and covariance showed no significant differences in worm caloric content with withdrawal day or cadmium concentration.

In a second experimental series, a sediment toxicity test with Neanthes virens was conducted in contaminated sediments from two sites, as well as reference sediments from a control site. Caloric content of the worms was measured by bomb …

Cation Nuclear Magnetic Resonance (Nmr). 7li- And 23na-Nmr Results Obtained With Human Erythrocytes, Jan F. M. Post

Scanning Microscopy

A short discussion of practical results and theoretical aspects of nuclear magnetic resonance (NMR) on intracellular monovalent cations is presented. ⁷Li- and ²³Na-NMR relaxation studies on human erythrocytes are described which indicate that lithium and sodium ions are essentially free inside the cell. However, there is a contribution to transverse relaxation originating from cations diffusing through electric field gradients imposed by the cytoskeleton, which is reflected in the NMR line shape. ³⁹K-NMR results obtained by other authors for intracellular potassium are compared with the ⁷Li- and ²³Na-NMR results presented here. The few ³⁹K-NMR results …

Simultaneous Micro-Characterization Of The Superconducting And Structural Properties Of High-Tc Superconducting Films, R. P. Huebener, R. Gross

Scanning Microscopy

Important information on the local values of the critical temperature and the critical current density in high-T_c superconducting films is obtained by low-temperature scanning electron microscopy (LTSEM). The imaging principle of LTSEM is based on the local beam-induced heating effect and the detection of a voltage response signal in the current-biased specimen film. During the scanning process the sample is mounted on a low-temperature stage the temperature of which is electronically stabilized at some specific value in the range of interest. The local superconducting quantities measured by LTSEM can be correlated with the microstructure of the specimen film investigated …

Microscopy Analysis Of Dental Titanium Casting Investment Materials, H. J. Mueller

Scanning Microscopy

Scanning electron microscopy (SEM) analysis and qualitative energy dispersive x-ray microanalysis (EDS) of investment materials for dental titanium casting were performed. Two commercial investment materials, Ohara and Castmatic, and an experimental zirconia material were analyzed. The microstructural constituents and the unfired and fired structures were included. Larger refractory particles and matrix embedding smaller particles were observed with each material. Detection of aluminum, silicon, magnesium, zirconium and oxygen provided a basis to reason the presence of alumina (Al₂O₃), silica (SiO₂), magnesia (MgO), and zirconia (ZrO₂). Hence, Ohara contained quartz and an alumino-silicate, Castmatic …

The Water Vapor Conductance Of Squamate Reptilian Eggs: The Influence Of Scaling On Nesting Ecology., Louis A. Somma

Papers in Herpetology

Flexible-shelled eggs of squamate reptiles are strongly influenced by their surrounding microclimate, particularly the hydric conditions of the nest. The eggshell water vapor conductance of an egg can be an indication of its requirement for water from the nest. Ackerman et al. (1985. Physiol. Zool. 58:129-137) have described the scaling relationship for eggshell water vapor conductance (G_H2O) of flexible-shelled reptilian eggs (G_H2O = 981.8M^0.52). This scaling relationship was investigated with water vapor conductance data obtained from 8 species of lizards representing the families Iguanidae (Anolis carolinensis, A. sagrai, Sceloporus woodi, S. virgatus) …

Scanning Electron Microscopy Of Lung Following Alpha Irradiation, C. L. Sanders, K. E. Lauhala, K. E. Mcdonald

Scanning Microscopy

Pulmonary aggregation of inhaled ²³⁹PuO₂ particles leads to a cellular evolution of focal inflammation, fibrosis, epithelial dysplasia and lung tumor formation. Female Wistar rats were exposed to an aerosol of high-fired ²³⁹PuO₂ (initial lung burden, 3.9 kBq) and the lungs examined at intervals from 1 day to 700 days after exposure by light and scanning electron microscopy and autoradiography. Peribronchiolar Pu particle aggregation increased with time, resulting in well-defined focal inflammatory lesions after 120 days and fibrotic lesions after 180 days. A generalized hypertrophy and hyperplasia of nonciliated bronchiolar cells was seen at 15 days and …

Natural And Disturbance-Induced Demographic Variation In An Infaunal Polychaete, Nephtys Incisa, Roman Zajac, Robert B. Whitlatch

Biology and Environmental Science Faculty Publications

Demography of the infaunal polychaete Nephtys incisa was investigated for periods of 1 yr prior to and following disturbance (dredge material disposal) at a site in central Long Island Sound, USA. Infaunal grab samples were taken at 5 stations 200 m to 3 km apart. The demography of populations at each station was based on age-classes spanning juveniles to adults 4 + yr of age. Age-specific survivorship and fecundity were based on changes in mean density of each cohort and a positive correlation between female size and egg production, respectively. Analyses of population matrix models indicated pre-disposal populations had positive …

Biuret Staining And X-Ray Microanalysis For Locating Grafted Poly(Methyl Acrylate) On Wool Fibers, R. R. Bresee, P. A. Annis

Scanning Microscopy

Biuret reagent was used to stain wool fibers with copper so the location of a small amount of poly(methyl acrylate) grafted onto the fibers could be determined by energy dispersive x-ray microanalysis of copper. The grafted polymer was determined to be located in regions of the fibers where cuticle had been previously damaged. The amount of grafted polymer present was too small for secondary electron imaging to be useful for locating the polymer grafts.

Dendritic Oxide Growth On The Surface Of Liquid Gallium, Y. L. Wang, A. Raval, R. Levi-Setti

Scanning Microscopy

We have studied the oxidation of a liquid gallium surface with a high spatial resolution scanning ion microprobe. A 40 keV focused gallium ion beam, extracted from a liquid metal ion source, was employed, first, to sputter clean a 40 x 40 μm² area on a drop of liquid gallium, in a ultra high vacuum (UHV) specimen chamber. It was then used to monitor the oxide growth by secondary ion mass spectrometry imaging microanalysis while the chamber was gradually back-filled with oxygen. In the initial stages, gallium oxide grew in a dendritic pattern from the edge of the cleaned …

Surface And Grain Boundary Analysis Of High Temperature Superconductors, F. J. Himpsel, A. G. Schrott

Scanning Microscopy

The purpose of this paper is to survey the methods that are available for probing surfaces and grain boundaries of high temperature superconductors. Various surface-sensitive spectroscopies are applied to the analysis of YBa₂Cu₃O_7-x and Bi₂Sr₂CaCu₂O_8+x including photoelectron spectroscopy, spatially-resolved electron energy loss spectroscopy, and scanning electron microscopy (SEM). One of the major sources of contamination at surfaces and grain boundaries is found to be BaCO₃. The cleavage surface of single crystal Bi₂Sr₂CaCu₂O_8+x is inert and can be used to …

A Calculation Method Of X-Ray Emitted Intensity In Multi-Layer Films By Monte Carlo Simulation, Yen-Cai Ho, Jia-Guang Chen, Xin-Lei Wang

Scanning Microscopy

A calculation method of X-ray emitted intensity in multi-layer films is proposed in this paper. The method is based on the work developed by us: (1) a simplified physical model of electron scattering and Monte Carlo evaluations in a single medium and in multi-layer media and (2) the theories and the formulae for excitation, absorption and fluorescence of characteristic X-rays. The intensity ratio of X-rays for the known thickness films, Au/Cu/Si and Cr/Ni/Si, were calculated at 20, 25 and 30 keV. Calculated results are compared with experimental values of electron microprobe analysis for the multi-layer film specimens, and the correspondence …

Dietary Protein Deficiency And Mycobacterium Bovis Bcg Affect Interleukin-2 Activity In Experimental Pulmonary Tuberculosis, David N. Mcmurray, C. L. Mintzer, R. A. Bartow, Rebecca D. Parr

Faculty Publications

Inbred strain 2 guinea pigs were vaccinated with Mycobacterium bovis BCG or were left unvaccinated. They were maintained for 6 weeks on defined, isocaloric diets containing either 30% (control animals) or 10% (animals receiving low protein) ovalbumin as the sole protein source. Animals were challenged by the respiratory route with a low dose of virulent M. tuberculosis H37Rv and killed 4 weeks later. Protein-malnourished animals were not protected by previous vaccination with BCG. Lymphocytes isolated from various tissues were tested in vitro for proliferative responses to mitogen (concanavalin A) and antigen (purified protein derivative [PPD]), production of interleukin-2 (IL-2), and …

Direct Genomic Sequencing Of Bacterial Dna: The Pyruvate Kinase I Gene Of Escherichia Coli, Osamu Ohara, Robert L. Dorit, Walter Gilbert

Biological Sciences: Faculty Publications

The genomic sequencing procedure is applied to the direct sequencing of uncharacterized regions of bacterial DNA by a "multiplex walking" approach. Samples of bulk Escherichia coli DNA are cut with various restriction enzymes, subjected to chemical sequencing degradations, run in a sequencing gel, and transferred to nylon membranes. When a labeled oligomer is hybridized to a membrane, a sequence ladder appears wherever the probe lies near a restriction cut. New probes, based on sequence that lies beyond other restriction sites, are then synthesized, and the membranes are reprobed to reveal new sequence. Repeated cycles of oligomer probe synthesis and subsequent …

Drosophila Nuclear Proteins Bind To Regions Of Alternating C And T Residues In Gene Promoters, D Gilmour, G Thomas, Sarah C.R. Elgin

Biology Faculty Research

Proteins from Drosophila nuclei that bind to regions of alternating C and T residues present in the promoters of the heat shock genes hsp70 and hsp26 and the histone genes his3 and his4 have been purified. These proteins bind to isolated linear DNA, and genomic footprinting analyses indicate that they are bound to DNA in nuclei. In supercoiled plasmids at low pH, some of these DNA sequences adopt triple-helical structures which, if they form in vivo, could significantly affect chromatin structure. The nuclear proteins described here, and not necessarily the deformed conformation of the DNA, may be responsible for maintaining …

Micronuclear Genome Organization In Euplotes Crassus: A Transposonlike Element Is Removed During Macronuclear Development, Scott Everet Baird, Gina M. Fino, Susan L. Tausta, Lawrence A. Klobutcher

Biological Sciences Faculty Publications

After mating, hypotrichous ciliated protozoa transform a set of their micronuclear chromosomes into thousands of short, linear DNA molecules that form the macronuclear genome. To examine micronuclear genome organization in the hypotrich Euplotes crassus, we have analyzed two cloned segments of micronuclear DNA as well as the macronuclear DNA molecules that are derived from them. E. crassus was found to display a number of features characteristic of other hypotrich genomes, including (i) clustering and close spacing of the precursors of macronuclear DNA molecules, (ii) the frequent occurrence of internal eliminated sequences within macronuclear precursors, (iii) overlapping macronuclear precursors, (iv) lack …

Kinetic Properties Of Hexokinase Under Near-Physiological Conditions: Relation To Metabolic Arrest In Artemia Embryos During Anoxia, Bernard Rees

Biological Sciences Faculty Publications

Previous analyses of glycolytic metabolites in Artemia embryos indicate that an acute inhibition of glucose phosphorylation occurs during pHi-mediated metabolic arrest under anoxia. We describe here kinetic features of hexokinase purified from brine shrimp embryos in an attempt to explain the molecular basis for this inhibition. At saturating concentrations of cosubstrate, ADP is an uncompetitive inhibitor toward glucose and a partial noncompetitive inhibitor toward ATP (Kis = 0.86 mM, Kii = 1.0 mM, Kid = 1.9 mM). With cosubstrates at subsaturating concentrations, the uncompetitive inhibition versus glucose becomes noncompetitive, while inhibition versus ATP remains partial noncompetitive. The partial noncompetitive inhibition …

The Voltage Sensor Of Excitation-Contraction Coupling In Skeletal Muscle. Ion Dependence And Selectivity, Gonzalo Pizarro, Robert H. Fitts, Ismael Uribe, Eduardo Rios

Biological Sciences Faculty Research and Publications

Manifestations of excitation-contraction (EC) coupling of skeletal muscle were studied in the presence of metal ions of the alkaline and alkaline-earth groups in the extracellular medium. Single cut fibers of frog skeletal muscle were voltage clamped in a double Vaseline gap apparatus, and intramembrane charge movement and myoplasmic Ca2+ transients were simultaneously measured. In metal-free extracellular media both charge movement of the charge 1 type and Ca transients were suppressed. Under metal-free conditions the nonlinear charge distribution was the same in depolarized (holding potential of 0 mV) and normally polarized fibers (holding potentials between -80 and -90 mV). The manifestations …

The Dark Side Of Bright Metal Coatings, L. Bartosiewicz, C. J. Kelly

Scanning Microscopy

The surface quality of light reflective metal films on polymer substrates were experimentally examined and evaluated. The study included light optical hotstage microscopy of in-situ samples and scanning electron microscopy. Conditions for producing aluminum metal films with desirable light reflecting properties are relatively demanding. The film formation is a complex series of events which include nucleation, coalescence and crystal growth.

Surface flaws, debris or other imperfections are readily visualized with the aid of the optical or the electron microscope. Although complex methods have been developed for the examination of small surface areas with fine-featured metallic films, there was little incentive …

Endothelial Injury In Human Atherosclerosis, G. Pasquinelli, A. Cavazza, P. Preda, A. Stella, B. I. Cifiello, M. Gargiulo, M. D'Addato, R. Laschi

Scanning Microscopy

A light and electron microscopic investigation (scanning and transmission electron microscopy) was performed on 51 human atherosclerotic carotid lesions. The purpose of this study was to establish whether features of endothelial injury such as those described in animals occur in man and whether these features can be related to specific stages of human atherosclerosis.

Irrespective of their histological appearance the atherosclerotic lesions were covered with endothelium which showed non-specific changes in cell shape and size. However, all complicated lesions appeared denuded. Moreover, a peculiar interaction of endothelium with monocytes and lymphocytes as well as blood components (e.g., fibrin and lipoproteins) …

A Contribution To The Scanning Electron Microscope Based Microcharacterization Of Semi-Insulating Gallium Arsenide Substrates, D. Köhler, G. Koschek, E. Kubalek

Scanning Microscopy

The macroscopic behaviour of semiconducting materials is determined by the distribution of microscopic defects like dislocations, impurities and intrinsic defects. Therefore, microanalytical methods are necessary to control the influence of technological process parameters on the materials properties. In the case of GaAs substrates, measurements of the cathodoluminescence (CL) and the electron beam induced voltage (EBIV) as well as the new charging technique seem to be promising methods to perform this task. CL-micrographs of as-grown GaAs substrates show bright cellular structures, which correspond to dislocation networks. Comparative investigations by use of the new charging contrast technique indicate an increased conductivity in …

Effects Of Inter-Specific Density And Food Supply On Survivorship And Growth Of Newly Settled Benthos, Roman Zajac, Robert B. Whitlatch, Richard W. Osman

Biology and Environmental Science Faculty Publications

Using a laboratory model system comprised of newly settled oysters Crassostrea virginica and established fouling species (Botrylloides sp. initially, and others including Styela clava and Ciona intestinalis as the experiment progressed), we tested how differences in food supply and competitor density may affect post-settlement surivorship and growth of sessile marine invertebrates over a 44 d period. After 15 d, results were mixed but indicated that both food and density conditions affected growth and survivorship significantly, with some suggestion of high food levels ameliorating high density effects However, 44 d after settlement, oysters had reduced survivorship and growth when competitors …

Effects Of Dietary Corn Oil And Menhaden Oil On Rats Mammary Tumorigenesis And Prostaglandin E2 Levels, Melissa L. Philley

Morehead State Theses and Dissertations

A thesis presented to the faculty of the College of Arts and Sciences at Morehead State University in partial fulfillment of the requirements for the Degree of Master of Science in Biology by Melissa L. Philley on August 4, 1989.

Hypercholesterolemia And Platelet Sensitivity To Thromb In-Induced Aggregation In Whole Blood, Charles E. Hammond Ii

Morehead State Theses and Dissertations

A thesis presented to the faculty of the College of Arts and Sciences at Morehead State University in partial fulfillment of the requirements for the Degree of Master of Sciences in Biology by Charles E. Hammond, II on August 1, 1989.

Dynamics Of Mitochondrial Dna Evolution In Animals: Amplification And Sequencing With Conserved Primers, T. D. Kocher, W. K. Thomas, A. Meyer, S. V. Edwards, S. Pääbo, F. X. Villablanca, A. C. Wilson

Biological Sciences

With a standard set of primers directed toward conserved regions, we have used the polymerase chain reaction to amplify homologous segments of mtDNA from more than 100 animal species, including mammals, birds, amphibians, fishes, and some invertebrates. Amplification and direct sequencing were possible using unpurified mtDNA from nanogram samples of fresh specimens and microgram amounts of tissues preserved for months in alcohol or decades in the dry state. The bird and fish sequences evolve with the same strong bias toward transitions that holds for mammals. However, because the light strand of birds is deficient in thymine, thymine to cytosine transitions …

Distribution And Marketing Of Western Australia Rock Lobster., P. J. Monaghan

Fisheries Management Papers

This report describes the marketing and distribution of Western Australian rock lobster products in the major consuming countries namely, USA, Japan and Taiwan. It is based on a study which was commissioned by the Fisheries Department of Western Australia who sought, for the benefit of industry generally, an understanding of the world lobster markets.

One-Sided Polymerase Chain Reaction: The Amplification Of Cdna, Osamu Ohara, Robert L. Dorit, Walter Gilbert

Biological Sciences: Faculty Publications

We report a rapid technique, based on the polymerase chain reaction (PCR), for the direct targeting, enhancement, and sequencing of previously uncharacterized cDNAs. This method is not limited to previously sequenced transcripts, since it requires only two adjacent or partially overlapping specific primers from only one side of the region to be amplified. These primers can be located anywhere within the message. The specific primers are used in conjunction with nonspecific primers targeted either to the poly(A)+ region of the message or to an enzymatically synthesized d( A) tail. Pairwise combinations of specific and general primers allow for the amplification …