bluuebunny/crossref_metadata_2025_split huggingface dataset:
Effect of bacterial flagellin on thiamin uptake by human and mouse pancreatic acinar cells: inhibition mediated at the level of transcription of thiamin transporters 1 and 2
Authors: Srinivasan Padmanabhan , Anandam Kasin Yadunandam , Ramesh Vignesh , Geltz Erica T. , Said Hamid M. 
Published: March 2019

Thiamin (vitamin B1) is essential for normal cellular metabolism and function. Pancreatic acinar cells (PACs) obtain thiamin from the circulation via a specific carrier-mediated process that involves the plasma membrane thiamin transporters 1 and 2 (THTR-1 and THTR-2; products of SLC19A2 and SLC19A3 genes, respectively). There is nothing known about the effect of bacterial products/toxins on thiamin uptake by PACs. We addressed this issue in the present investigation by examining the effect of bacterial flagellin on physiological and molecular parameters of thiamin uptake by PACs. We used human primary PACs, mice in vivo, and cultured mouse-derived pancreatic acinar 266-6 cells in our investigation. The results showed that exposure of human primary PACs to flagellin led to a significant inhibition in thiamin uptake; this inhibition was associated with a significant decrease in expression of THTR-1 and -2 at the protein and mRNA levels. These findings were confirmed in mice in vivo as well as in cultured 266-6 cells. Subsequent studies showed that flagellin exposure markedly suppressed the activity of the SLC19A2 and SLC19A3 promoters and that this effect involved the Sp1 regulatory factor. Finally, knocking down Toll-like receptor 5 by use of gene-specific siRNA was found to lead to abrogation in the inhibitory effect of flagellin on PAC thiamin uptake. These results show, for the first time, that exposure of PACs to flagellin negatively impacts the physiological and molecular parameters of thiamin uptake and that this effect is mediated at the level of transcription of the SLC19A2 and SLC19A3 genes. NEW & NOTEWORTHY The present study demonstrates, for the first time, that prolonged exposure of pancreatic acinar cells to flagellin inhibits uptake of vitamin B1, a micronutrient that is essential for energy metabolism and ATP production. This effect is mediated at the level of transcription of the SLC19A2 and SLC19A3 genes and involves the Sp1 transcription factor.
Oxidative pathophysiology following volumetric muscle loss injury in a porcine model
Authors: Chao Tony , Burmeister David M. , Corona Benjamin T. , Greising Sarah M. 
Published: March 2019

Volumetric muscle loss (VML) occurs after severe orthopedic trauma and results in loss of muscle fibers and function that can leave patients permanently disabled. Although animals models of VML are useful to test possible therapeutic strategies, the pathophysiological characteristics of remaining skeletal muscle and changes in metabolism are not thoroughly understood. Herein, alterations of neuromuscular function, muscle fiber morphology, myosin heavy chain expression, and myofiber mitochondrial respiration were evaluated in an adult Yorkshire swine VML injury model. VML injured animals showed reduced peak isometric strength ( P < 0.05) and a shift toward smaller muscle fibers independent of fiber type ( P < 0.001). The muscle remaining after VML had a greater distribution of type I fibers and lower distribution of type II fibers ( P < 0.001). Skeletal muscle mitochondrial state 2 and state 3, reflecting complex I respiration, increased after injury ( P < 0.05) with a consistent trend to display higher oxygen flux per milligram of tissue. However, this was largely driven by increased mitochondrial content after VML which was associated with higher mitochondrial fission (FIS-1 protein levels). This study demonstrates an underlying perturbation of oxidative metabolism within the remaining musculature following surgical creation of an isolated, sterile VML injury in a porcine model that may be influential to the development of insidious pathophysiology and regenerative and rehabilitative therapies. NEW & NOTEWORTHY The natural injury sequela of volumetric muscle loss (VML) and associated pathophysiology of the remaining muscle is still incompletely understood. Herein we demonstrate a chronic muscle function deficit, with an increase in type I muscle fibers and parallel increase in oxidative capacity of remaining skeletal muscle. It is possible that the alteration in oxidative capacity after VML could largely be due to heightened mitochondrial activity and an increase in mitochondrial abundance.
Endurance exercise training restores atrophy-induced decreases of myogenic response and ionic currents in rat skeletal muscle artery
Authors: Yin Ming Zhe , Kim Hae Jin , Suh Eun Yeong , Zhang Yin Hua , Yoo Hae Young , Kim Sung Joon 
Published: March 2019

Atrophic limbs exhibit decreased blood flow and histological changes in the arteries perfusing muscles. However, the effect of atrophy on vascular smooth muscle function is poorly understood. Here, we investigated the effect of unilateral sciatic denervation on the myogenic response (MR) and the ionic currents in deep femoral artery (DFA) smooth muscles from Sprague-Dawley rats. Because denervated rats were capable of treadmill exercise (20 m/min, 30 min, 3 times/wk), the impact of exercise training on these effects was also assessed. Skeletal arteries were harvested 3 or 5 wk after surgery. Then skeletal arteries or myocytes were subjected to video analysis of pressurized artery, myography, whole-cell patch clamp, and real-time quantitative PCR to determine the effect of hindlimb paralysis in the presence/absence of exercise training on MR, contractility, ionic currents, and channel transcription, respectively. In sedentary rats, atrophy was associated with loss of MR in the DFA at 5 wk. The contralateral DFA had a normal MR. At 5 wk after surgery, DFA myocytes from the atrophic limbs exhibited depressed L-type Ca2+currents, GTPγS-induced transient receptor potential cation channel (TRPC)-like currents, 80 mM KCl-induced vasoconstriction, TRPC6 mRNA, and voltage-gated K+and inwardly rectifying K+currents. Exercise training abrogated the differences in all of these functions between atrophic side and contralateral side DFA myocytes. These results suggest that a probable increase in hemodynamic stimuli in skeletal artery smooth muscle plays an important role in maintaining MR and ionic currents in skeletal artery smooth muscle. This may also explain the observed benefits of exercise in patients with limb paralysis.NEW & NOTEWORTHY Myogenic responses (MRs) in rat skeletal arteries feeding the unilateral atrophic hindlimb were impaired. In addition, the L-type Ca2+channel current, the TRPC6-like current, and TRPC6 mRNA levels in the corresponding myocytes decreased. Voltage-gated K+channel currents and inwardly rectifying K+channel currents were also attenuated in atrophic side myocytes. Exercise training effectively abrogated electrophysiological dysfunction of atrophic side myocytes and prevented loss of the MR.
The New Hilger Microfocus X-Ray Generator and Its Applications
Authors: Brech Frederick , Stansfield J. R. 
Published: March 2019

AbstractIn X-ray diffraction techniques intensity of radiation is an important factor. In addition, when high resolution is required, the usual collimating system restricts the width of focus that can be effectively used. Accordingly, a prime requirement is that the target loading shall be high to give the greatest possible brilliance at the focus. An X-ray unit designed to achieve these qualities will be described. Its use with a spectrometer and with a number of cameras for differing crystallographic studies will be illustrated.The tube operates with alternative electron guns, one of them to provide a circular focus of 40 microns in diameter and the other to provide a line focus of 1.4 millimeters in length and 0. 1 millimeter in width.
Early Aging Effects in Copper - 1.76% Beryllium Single Crystals
Authors: Evans Doris 
Published: March 2019

AbstractA technique is described for the study of the early stages of precipitation hardening in single-crystalline and poly crystalline copperberyllium alloys. Since no trace of the equilibrium precipitate responsible for hardening can be detected by ordinary X-ray or metallographic techniques prior to the onset of overaging, the described method is based on the changes produced in the matrix as the result of the formation of aggregates along preferred lattice planes. Such formations produce accommodation strains in the matrix lattice which, can be detected as a change in the intensity and angular range of matrix reflection.An interpretation of the age hardening sequence in a copper - beryllium, alloy after isothermal annealing is presented in terms of fundamental transformations.
Application of the Microemission X-Ray Spectrograph. Comparison of Analyses from Small Areas
Authors: Norton J. F. 
Published: March 2019

AbstractTechniques of determining spot size and sensitivity of the instrument will be developed. Spot sizes of the order of 5 microns have been obtained with the possibility remaining for improvement- Preliminary sensitivity measurements indicate that micro-microgram quantities of some elements are sufficient to be detected. Difficulties involved in finding desired target areas will be discussed. The inhomogeneities of standard samples used for conventional fluorescense X-ray quantitative analyses precludes their use for microemission techniques at least in some cases. Possible ways of determining homogeneity will be discussed. Analysis which can be performed to advantage may be classed into several categories.1.The changes in composition occurring in grain boundaries can be detected and compared with the base material.2.An inclusion, in a metallic material can be brought under the electron probe and analyzed independently of the base material.3.Changes in composition across a boundary between solid phases can be measured.4.Diffusion coefficients between solid phases may be determined.5.Thickness of thin films and variations in film thickness can be measured.Examples of the instrument's performance will be given in some of these categories.
A Theoretical Derivation of the Composition of Mixable Specimens from Fluorescent X-Ray Intensities
Authors: Sherman Jacob 
Published: March 2019

AbstractA rigorous solution is developed for the correlation of the composition of mixable specimens and the fluorescent X-radiation emitted by the elements in the specimen. The instrumental modifications and treatment of the specimens are derived from the fundamental fluorescence equation.The resultant dilution formula contains measurable quantities only. No calibration curve is required.The theory is illustrated by some experimental data confirming the equations.
A Novel Approach to Discrimination in X-Ray Spectrographic Analysis
Authors: Lublin Paul 
Published: March 2019

AbstractThere are various methods for handling the problem of interferences. One may me one of the weaker lines of the trace clement, but this results in considerable loss in the limit of detectability of this element. One may try pulse height discrimination techniques, but because of the linearity limitations of present day pulse height analyzers, complete elimination of the higher energy wave length is not possible. Another possible technique is to lower the kilovoltage below the excitation potential of the interfering element. This is satisfactory, but again the limit of detectability is raised for the trace element. There are many other “devices” which may be tried, but all of these involve a loss in sensitivity in the determination of the trace element.The “novel” approach involves the use of an analyzing crystal whose second order reflection is missing due to crystal structure considerations. Germanium or silicon, cut so that (111) planes are parallel to the surface of the crystal, would be satisfactory analyzers for this purpose. The use of one of these crystals and the application of this method to the niobium-tantalum and zirconium-hafnium systems are discussed.
Crystal Chemical Studies by X-Ray Fluorescence
Authors: White Eugene W. , McKinstry Herbert A. , Bates Thomas F. 
Published: March 2019

AbstractThe wavelength of the characteristic X-radiation for the lighter elements is not constant but is a function of valence state and to a much lesser extent is a function of co-ordination number.Commercially available X-ray fluorescence equipment is used in detecting shifts in the characteristic radiation for aluminum, sulfur, chlorine, titanium, vanadium and iron. The greatest shift is found in the case of chlorine where, using the NaCl analyzer, a shift of nearly 0.2° 2 θ is obtained in going from the Cl− in cholorides to the Cl+7 in the perchloratc. The wavelength of the Al+3Kα varies slightly as a function of co-ordination number.Examples are given for using these phenomena in studying minerals and other compounds. The feasibility of extending the study to both heavier and lighter elements is explored.
An X-Ray Fluorescence Method of Analysis of Microsamples
Authors: Reisdorf B. G. 
Published: March 2019

AbstractA method is described for the analysis of microscopic samples that utilizes a commercial electron diffraction unit for the excitation of fluorescent X-rays in a specimen and photographic recording of the resulting spectra by a small fluorescenceanalysis camera placed within the electron diffraction unit. Applications of this method to the analysis of precipitates extracted from steels are included in the discussion.
A High-Temperature Study of Phase Precipitation in Superalloys
Authors: Radavich John F. 
Published: March 2019

AbstractMany of the iron- and nickel-base superalloys exhibit brittle properties on heat treatment, welding, or other fabrication processes at temperatures of about 2000°F or higher. Studies have been carried out by means of electron microscopy, electron diffraction, and X-ray diffraction and fluorescence analysis of the precipitation in the metal and in an isolated form.Results of the electron microscope study of the surface of the metal show a grain boundary constituent to be present which increases in amount as the temperature is increased. Studies on the isolated residue of such samples show a very thin “featherlike” film to be located at the grain boundaries and enclosing the grains. Electron diffraction, X-ray diffraction, and X-ray fluorescence analysis studies of the thin films indicate that they are a TiC phase with very little alloying elements in solution.At temperatures above 2000°F the thin film becomes quite thick and tends to force the grains apart. It is believed that this form of the TiC phase promotes the severe embrittling nature of these alloys at high temperatures. Suitable heat treatment at lower temperatures causes the TiC film to agglomerate and the grain boundaries become “tight,” and a more ductile condition results.
The Use of Computer Techniques to Plot Pole Figures
Authors: Holland J. H. , Engler N. , Powers W. 
Published: March 2019

AbstractA method has been derived and is currently being used to plot normalized pole figures by computer techniques. As the pole distribution traces, i.e., intensity of the diffracted X-ray beam, versus angular position of the specimen are not an acceptable input for the computer, the data required from such traces are entered onto IBM punch cards. Corrections for defocusing effects may be readily made as the data are transferred from the Brown recorder traces to IBM punch cards. It is possible to program other correction factors into the computer operations providing that these correction factors or curves can be established accurately. The computer translates angular position of the specimen into reactiiinear coordinates which are an identical representation of stereographic coordinates. This computer method has been used in conjunction with the Schulz reflection technique, but modification of the computer program permits its use with other quantitative X-ray techniques for determining preferred orientation.The feasibility of using computer techniques to plot inverse pole figures has been considered.
X-Ray Studies of Basic Lead Azides
Authors: Stammler M. , Abel J. E. 
Published: March 2019

AbstractBasic lead azides are obtained by the slow thermal decomposition of PbN6 at temperatures up to 200°C in oxygen, argon, and air containing varying amounts of moisture. The decomposition diagrams show several stages due to the formation of different phases, two of which have been separated. One phase can be identified as a tetragonal deformed cubic lattice. Further slow decompositions of the basic lead azide at 250°C lead to tetragonal lead oxide. The structure of the other isolated phase Is of lower symmetry and has not yet been classified. The results of this investigation are also compared with the work of previous investigators.
A Simple Goniostat for the Norelco Diffractometer
Authors: Hubbard William M. , Gilfrich John V. 
Published: March 2019

AbstractA simple single-crystal goniostat has been built for the Norelco X-ray diffractometer using a modified eucentric goniometer head and the basic geometry of the Norelco pole-figure device.The goniometer head was modified to provide interchangeable mounting tn the goniostat, a two-circle optical goniometer, or the sample holder of a flat-plate camera.With this device one can orient and mount a. crystal along any desired direction in a fraction of the time required by conventional film techniques, thus reducing the mounting of a sample for intensity measure ment s for structure determinations or for measurements of anisotropic physical properties to a routine procedure.
The Effect of Particles and Surface Irregularities on the X-Ray Fluorescent
Intensity of Selected Substances
Authors: Gunn E.L. 
Published: March 2019

AbstractSelected substances have been examined by X-ray fluorescence to determine the effect of particles or surface irregularities on the fluorescent intensity. The powdered substances examined were segregated into particle size classifications by the use of standard and micro sieves and ocular microscopic measurements. The substances thus classified were Iron, germanium, and titanium metals, copper furnace slag, and a cobalt molybdate catalyst. Graphical representations are used to characterize the relation between particle size and intensity. In certain cases the influence of particle size is expressed in terms of a calculated absorption length of the substance. The extent to which particle size in a powder affects the fluorescent intensity is a function of the absorption coefficients of the substance for the exciting and fluorescent X-rays, The effect on intensity of successive powder dilution of a high atomic number witha low atomic number substance has been measured. The results are of assistance in providing a concept of the structure necessary for maximum intensity. Little difference in the fluorescent intensity of an element is exhibited as between its dilution in a dry powder and in an aqueous solution, if the absorption properties of the two diluents are very similar. The effect of small surface irregularities in a metal exhibits no systematic relation to the fluorescent intensity.
Norelco Pinhole Attachment
Authors: Miller D.C. 
Published: March 2019

AbstractAn adapter for a standard Norelco spectrographte attachment will be described which permits the examination of a selected area of the specimen by X-ray fluorescence analysis. The size of the area can be varied depending upon the choice of pinholes with sizes available dovwi to 0.010 in. or 250μ. The sample is placed into a specially modified sample holder so that it can be moved at orthogonal directions under the beam from outside the spectrograph while the sample is under X-ray irradiation. Dam on applications will also be given.
X-Ray Diffraction Studies at Low Temperatures
Authors: Barrett Charles S. 
Published: March 2019

AbstractMuch current solid-state research, particularly that concerning the Fermi surfaces of metals and semimetals, demands knowledge of lattice parameters at temperatures in the liquid-helium range. A helium cryostat diffraction apparatus that has been in continuous use at these temperatures will be described, and some new research results from it are presented. The results include measurements of the lattice constants for gallium and for indium, of interest because the axial ratio influences both the nuclear electric quadrupole spectrum and also the cyclotron resonance. Previous measurements have disclosed unusual expansion characteristics but have not extended below liquid-nitrogen temperature.A second area in which the cryostat has been operating is the determination of the temperature of beginning recrystallization in high-purity metals that recrystallize at low temperatures. Experiments with zone-refined lead which has a recrystallization temperature near 160°K are reported.
X-Ray Diffraction Investigation of the Sn-Hg Phase in Dental Amalgam*
Authors: Fairhurst Carl W. , Ryge Gunnar 
Published: March 2019

AbstractDental amalgam has been used as a filling material in dentistry for over 100 years. The reactants, Ag3Sn alloy and mercury, form silver-mercury and tin-mercury products. Previous X-ray diffraction studies have resulted in some disagreement concerning unit-cell structure and parameters of the products. In this study, X-ray diffraction measurements were carried out on tin-mercury mixtures, tin-mercury alloys, dental amalgam, and single crystals of tin and mercury. The diffraction data for the tin-mercury alloys were programed for an IBM 650 computer utilizing Cohen's least-squares method. The tin-mercury product was found to be a solid solution possessing hexagonal-symmetry elements. The parameters ranged from: c0= 2.995 A to 2.984 A, co/ao= 0.931.
Determination of Accurate Lattice Parameters Using a Diffractometer
Authors: Geiss R.H. 
Published: March 2019

AbstractWithout modifying the General Electric XRD-5 diffractometer accurate lattice parameters of cubic structures may be determined quite simply and precisely. The method is applicable to both solid and powder samples and gives a precision of at least ±0.00025 A. The most important step in the analysis is the alignment of the diffractometer. The specimen must be in the exact center for precise work. However, after the initial alignment, daily alignment is a routine matter. This technique for lattice-parameter determination will also be useful for determining thermal coefficients of expansion and residual-stress measurements.
A Study of Cuban Todorokite
Authors: Faulring G. M. 
Published: March 2019

AbstractTodorokite is a hydrated manganese oxide mineral containing small amounts of sodium, potassium, calcium, barium, magnesium, iron, and aluminum. From the reports of other investigators and observations in our laboratories, todorokite appears to be a more widely occurring mineral than generally recognized.It was found by X-ray diffraction that a sample of todorokite from Charco Redondo, Cuba, had a high degree of preferred orientation and that milling for a prolonged period of time was necessary to obtain random orientation in a mounted specimen. The position of the preferred orientation direction with respect to the X-ray beam is the principal factor determining the relative intensities on an X-ray diffraction pattern. Based on fiber data, the unit cell of todorokite is considered to be pseudo-orthorhombic or triclinic with α, β, and γ angles varying slightly from 90° and cell dimensions of a0 = 9.65A, b0 = 10.29A, and c0 = 2.84A, This deviation from orthogonality may account for the diffuse and distinct reflections typical of X-ray diffraction patterns of todorokite. Optical data and a hypothesized paragenesis of Cuban todorokite are also included.