1
|
Adamson SE, Hughes JW. Paracrine Signaling by Pancreatic Islet Cilia. Curr Opin Endocr Metab Res 2024; 35:100505. [PMID: 38524256 PMCID: PMC10956557 DOI: 10.1016/j.coemr.2024.100505] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 03/26/2024]
Abstract
The primary cilium is a sensory and signaling organelle present on most pancreatic islet endocrine cells, where it receives and interprets a wide range of intra-islet chemical cues including hormones, peptides, and neurotransmitters. The ciliary membrane possesses a molecular composition distinct from the plasma membrane, with enrichment of signaling mediators including G protein-coupled receptors (GPCRs), tyrosine kinase family receptors, membrane transporters and others. When activated, these membrane proteins interact with ion channels and adenylyl cyclases to trigger local Ca2+ and cAMP activity and transmit signals to the cell body. Here we review evidence supporting the emerging model in which primary cilia on pancreatic islet cells play a central role in the intra-islet communication network and discuss how changes in cilia-mediated paracrine function in islet cells might lead to diabetes.
Collapse
Affiliation(s)
- Samantha E Adamson
- Division of Endocrinology, Metabolism & Lipid Research, Washington University School of Medicine, St. Louis, MO, USA
| | - Jing W Hughes
- Division of Endocrinology, Metabolism & Lipid Research, Washington University School of Medicine, St. Louis, MO, USA
| |
Collapse
|
2
|
Sviben S, Polino AJ, Melena I, Hughes JW. Immuno-Scanning Electron Microscopy of Islet Primary Cilia. bioRxiv 2024:2024.02.16.580695. [PMID: 38405740 PMCID: PMC10888824 DOI: 10.1101/2024.02.16.580695] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/27/2024]
Abstract
The definitive demonstration of protein localization on primary cilia has been a challenge for cilia biologists. Primary cilia are solitary thread-like projections that contain specialized protein composition, but as the ciliary structure overlays the cell membrane and other cell parts, the identity of ciliary proteins are difficult to ascertain by conventional imaging approaches like immunofluorescence microscopy. Surface scanning electron microscopy combined with immuno-labeling (immuno-SEM) bypasses some of these indeterminacies by unambiguously showing protein expression in the context of the 3D ultrastructure of the cilium. Here we apply immuno-SEM to specifically identify proteins on the primary cilia of mouse and human pancreatic islets, including post-translationally modified tubulin, intraflagellar transport (IFT) 88, the small GTPase Arl13b, as well as subunits of axonemal dynein. Key parameters in sample preparation, immuno-labeling, and imaging acquisition are discussed to facilitate similar studies by others in the cilia research community.
Collapse
|
3
|
Adamson SE, Li ZA, Hughes JW. Beta cell primary cilia mediate somatostatin responsiveness via SSTR3. Islets 2023; 15:2252855. [PMID: 37660302 PMCID: PMC10478741 DOI: 10.1080/19382014.2023.2252855] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/01/2023] [Revised: 08/23/2023] [Accepted: 08/24/2023] [Indexed: 09/05/2023] Open
Abstract
Somatostatin is a paracrine modulator of insulin secretion and beta cell function with pleotropic effects on glucose homeostasis. The mechanism of somatostatin-mediated communication between delta and beta cells is not well-understood, which we address in this study via the ciliary somatostatin receptor 3 (SSTR3). Primary cilia are membrane organelles that act as signaling hubs in islets by virtue of their subcellular location and enrichment in signaling proteins such as G-protein coupled receptors (GPCRs). We show that SSTR3, a ciliary GPCR, mediates somatostatin suppression of insulin secretion in mouse islets. Quantitative analysis of calcium flux using a mouse model of genetically encoded beta cell-specific GCaMP6f calcium reporter shows that somatostatin signaling alters beta cell calcium flux after physiologic glucose stimulation, an effect that depends on endogenous SSTR3 expression and the presence of intact primary cilia on beta cells. Comparative in vitro studies using SSTR isoform antagonists demonstrate a role for SSTR3 in mediating somatostatin regulation of insulin secretion in mouse islets. Our findings support a model in which ciliary SSTR3 mediates a distinct pathway of delta-to-beta cell regulatory crosstalk and may serve as a target for paracrine modulation.
Collapse
Affiliation(s)
- Samantha E. Adamson
- Department of Medicine, Division of Endocrinology, Metabolism & Lipid Research, Washington University School of Medicine, St. Louis, USA
| | - Zipeng A. Li
- Department of Medicine, Division of Endocrinology, Metabolism & Lipid Research, Washington University School of Medicine, St. Louis, USA
| | - Jing W. Hughes
- Department of Medicine, Division of Endocrinology, Metabolism & Lipid Research, Washington University School of Medicine, St. Louis, USA
| |
Collapse
|
4
|
Lee EY, Hughes JW. Rediscovering Primary Cilia in Pancreatic Islets. Diabetes Metab J 2023; 47:454-469. [PMID: 37105527 PMCID: PMC10404530 DOI: 10.4093/dmj.2022.0442] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/16/2022] [Accepted: 03/15/2023] [Indexed: 04/29/2023] Open
Abstract
Primary cilia are microtubule-based sensory and signaling organelles on the surfaces of most eukaryotic cells. Despite their early description by microscopy studies, islet cilia had not been examined in the functional context until recent decades. In pancreatic islets as in other tissues, primary cilia facilitate crucial developmental and signaling pathways in response to extracellular stimuli. Many human developmental and genetic disorders are associated with ciliary dysfunction, some manifesting as obesity and diabetes. Understanding the basis for metabolic diseases in human ciliopathies has been aided by close examination of cilia action in pancreatic islets at cellular and molecular levels. In this article, we review the evidence for ciliary expression on islet cells, known roles of cilia in pancreas development and islet hormone secretion, and summarize metabolic manifestations of human ciliopathy syndromes. We discuss emerging data on primary cilia regulation of islet cell signaling and the structural basis of cilia-mediated cell crosstalk, and offer our interpretation on the role of cilia in glucose homeostasis and human diseases.
Collapse
Affiliation(s)
- Eun Young Lee
- Department of Medicine, Washington University School of Medicine, St. Louis, MO, USA
- Division of Endocrinology and Metabolism, Department of Internal Medicine, Seoul St. Mary’s Hospital, College of Medicine, The Catholic University of Korea, Seoul, Korea
| | - Jing W. Hughes
- Department of Medicine, Washington University School of Medicine, St. Louis, MO, USA
| |
Collapse
|
5
|
Polino AJ, Sviben S, Melena I, Piston DW, Hughes JW. Scanning electron microscopy of human islet cilia. Proc Natl Acad Sci U S A 2023; 120:e2302624120. [PMID: 37205712 PMCID: PMC10235940 DOI: 10.1073/pnas.2302624120] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2023] [Accepted: 04/12/2023] [Indexed: 05/21/2023] Open
Abstract
Human islet primary cilia are vital glucose-regulating organelles whose structure remains uncharacterized. Scanning electron microscopy (SEM) is a useful technique for studying the surface morphology of membrane projections like cilia, but conventional sample preparation does not reveal the submembrane axonemal structure, which holds key implications for ciliary function. To overcome this challenge, we combined SEM with membrane-extraction techniques to examine primary cilia in native human islets. Our data show well-preserved cilia subdomains which demonstrate both expected and unexpected ultrastructural motifs. Morphometric features were quantified when possible, including axonemal length and diameter, microtubule conformations, and chirality. We further describe a ciliary ring, a structure that may be a specialization in human islets. Key findings are correlated with fluorescence microscopy and interpreted in the context of cilia function as a cellular sensor and communications locus in pancreatic islets.
Collapse
Affiliation(s)
- Alexander J. Polino
- Department of Cell Biology and Physiology, Washington University School of Medicine, Saint Louis, MO63110
| | - Sanja Sviben
- Washington University Center for Cellular Imaging, Washington University School of Medicine, Saint Louis, MO63110
| | - Isabella Melena
- Department of Medicine, Washington University School of Medicine, Saint Louis, MO63110
| | - David W. Piston
- Department of Cell Biology and Physiology, Washington University School of Medicine, Saint Louis, MO63110
| | - Jing W. Hughes
- Department of Cell Biology and Physiology, Washington University School of Medicine, Saint Louis, MO63110
- Department of Medicine, Washington University School of Medicine, Saint Louis, MO63110
| |
Collapse
|
6
|
Chabosseau P, Yong F, Delgadillo-Silva LF, Lee EY, Melhem R, Li S, Gandhi N, Wastin J, Noriega LL, Leclerc I, Ali Y, Hughes JW, Sladek R, Martinez-Sanchez A, Rutter GA. Molecular phenotyping of single pancreatic islet leader beta cells by "Flash-Seq". Life Sci 2023; 316:121436. [PMID: 36706832 DOI: 10.1016/j.lfs.2023.121436] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2022] [Revised: 01/11/2023] [Accepted: 01/20/2023] [Indexed: 01/26/2023]
Abstract
AIMS Spatially-organized increases in cytosolic Ca2+ within pancreatic beta cells in the pancreatic islet underlie the stimulation of insulin secretion by high glucose. Recent data have revealed the existence of subpopulations of beta cells including "leaders" which initiate Ca2+ waves. Whether leader cells possess unique molecular features, or localisation, is unknown. MAIN METHODS High speed confocal Ca2+ imaging was used to identify leader cells and connectivity analysis, running under MATLAB and Python, to identify highly connected "hub" cells. To explore transcriptomic differences between beta cell sub-groups, individual leaders or followers were labelled by photo-activation of the cryptic fluorescent protein PA-mCherry and subjected to single cell RNA sequencing ("Flash-Seq"). KEY FINDINGS Distinct Ca2+ wave types were identified in individual islets, with leader cells present in 73 % (28 of 38 islets imaged). Scale-free, power law-adherent behaviour was also observed in 29 % of islets, though "hub" cells in these islets did not overlap with leaders. Transcripts differentially expressed (295; padj < 0.05) between leader and follower cells included genes involved in cilium biogenesis and transcriptional regulation. Providing some support for these findings, ADCY6 immunoreactivity tended to be higher in leader than follower cells, whereas cilia number and length tended to be lower in the former. Finally, leader cells were located significantly closer to delta, but not alpha, cells in Euclidian space than were follower cells. SIGNIFICANCE The existence of both a discrete transcriptome and unique localisation implies a role for these features in defining the specialized function of leaders. These data also raise the possibility that localised signalling between delta and leader cells contributes to the initiation and propagation of islet Ca2+ waves.
Collapse
Affiliation(s)
- Pauline Chabosseau
- Centre de Recherche du CHUM, Faculté de Médicine, Université de Montréal, Montréal, QC, Canada
| | - Fiona Yong
- Section of Cell Biology and Functional Genomics, Division of Diabetes, Endocrinology and Metabolism, Department of Metabolism, Digestion and Reproduction, Faculty of Medicine, Imperial College London, London W12 0NN, United Kingdom; Lee Kong Chian Imperial Medical School, Nanyang Technological University, Singapore
| | - Luis F Delgadillo-Silva
- Centre de Recherche du CHUM, Faculté de Médicine, Université de Montréal, Montréal, QC, Canada
| | - Eun Young Lee
- Department of Medicine, Washington University School of Medicine, Saint Louis, MO, United States; Division of Endocrinology and Metabolism, Department of Internal Medicine, Seoul St. Mary's Hospital, The Catholic University of Korea, Seoul, South Korea
| | - Rana Melhem
- Centre de Recherche du CHUM, Faculté de Médicine, Université de Montréal, Montréal, QC, Canada
| | - Shiying Li
- Centre de Recherche du CHUM, Faculté de Médicine, Université de Montréal, Montréal, QC, Canada
| | - Nidhi Gandhi
- Section of Cell Biology and Functional Genomics, Division of Diabetes, Endocrinology and Metabolism, Department of Metabolism, Digestion and Reproduction, Faculty of Medicine, Imperial College London, London W12 0NN, United Kingdom
| | - Jules Wastin
- Centre de Recherche du CHUM, Faculté de Médicine, Université de Montréal, Montréal, QC, Canada
| | - Livia Lopez Noriega
- Section of Cell Biology and Functional Genomics, Division of Diabetes, Endocrinology and Metabolism, Department of Metabolism, Digestion and Reproduction, Faculty of Medicine, Imperial College London, London W12 0NN, United Kingdom
| | - Isabelle Leclerc
- Centre de Recherche du CHUM, Faculté de Médicine, Université de Montréal, Montréal, QC, Canada
| | - Yusuf Ali
- Lee Kong Chian Imperial Medical School, Nanyang Technological University, Singapore
| | - Jing W Hughes
- Department of Medicine, Washington University School of Medicine, Saint Louis, MO, United States
| | - Robert Sladek
- Departments of Medicine and Human Genetics, McGill University and Genome Quebec Innovation Centre, Montreal, QC, Canada
| | - Aida Martinez-Sanchez
- Section of Cell Biology and Functional Genomics, Division of Diabetes, Endocrinology and Metabolism, Department of Metabolism, Digestion and Reproduction, Faculty of Medicine, Imperial College London, London W12 0NN, United Kingdom
| | - Guy A Rutter
- Centre de Recherche du CHUM, Faculté de Médicine, Université de Montréal, Montréal, QC, Canada; Section of Cell Biology and Functional Genomics, Division of Diabetes, Endocrinology and Metabolism, Department of Metabolism, Digestion and Reproduction, Faculty of Medicine, Imperial College London, London W12 0NN, United Kingdom; Lee Kong Chian Imperial Medical School, Nanyang Technological University, Singapore.
| |
Collapse
|
7
|
Mathews A, Hughes JW, Terry JL, Baek SG. Deep Electric Field Predictions by Drift-Reduced Braginskii Theory with Plasma-Neutral Interactions Based on Experimental Images of Boundary Turbulence. Phys Rev Lett 2022; 129:235002. [PMID: 36563220 DOI: 10.1103/physrevlett.129.235002] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/26/2022] [Accepted: 11/08/2022] [Indexed: 06/17/2023]
Abstract
We present two-dimensional turbulent electric field calculations via physics-informed deep learning consistent with (i) drift-reduced Braginskii theory under the framework of an axisymmetric fusion plasma with purely toroidal field and (ii) experimental estimates of the fluctuating electron density and temperature on open field lines obtained from analysis of gas puff imaging of a discharge on the Alcator C-Mod tokamak. The inclusion of effects from the locally puffed atomic helium on particle and energy sources within the reduced plasma turbulence model is found to strengthen correlations between the electric field and electron pressure. The neutrals are also directly associated with broadening the distribution of turbulent field amplitudes and increasing E×B shearing rates. This demonstrates a novel approach in plasma experiments by solving for nonlinear dynamics consistent with partial differential equations and data without encoding explicit boundary nor initial conditions.
Collapse
Affiliation(s)
- A Mathews
- Plasma Science and Fusion Center, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, USA
| | - J W Hughes
- Plasma Science and Fusion Center, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, USA
| | - J L Terry
- Plasma Science and Fusion Center, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, USA
| | - S G Baek
- Plasma Science and Fusion Center, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, USA
| |
Collapse
|
8
|
Abstract
Diabetes is a growing pandemic affecting over ten percent of the U.S. population. Individuals with all types of diabetes exhibit glucose dysregulation due to altered function and coordination of pancreatic islets. Within the critical intercellular space in pancreatic islets, the primary cilium emerges as an important physical structure mediating cell-cell crosstalk and signal transduction. Many events leading to hormone secretion, including GPCR and second-messenger signaling, are spatiotemporally regulated at the level of the cilium. In this review, we summarize current knowledge of cilia action in islet hormone regulation and glucose homeostasis, focusing on newly implicated ciliary pathways that regulate insulin exocytosis and intercellular communication. We present evidence of key signaling proteins on islet cilia and discuss ways in which cilia might functionally connect islet endocrine cells with the non-endocrine compartments. These discussions aim to stimulate conversations regarding the extent of cilia-controlled glucose homeostasis in health and in metabolic diseases.
Collapse
Affiliation(s)
| | - Jing W. Hughes
- Division of Endocrinology, Metabolism and Lipid Research, Department of Medicine, Washington University School of Medicine, Saint Louis, MO, United States
| |
Collapse
|
9
|
Odstrcil T, Laggner FM, Rosenthal AM, Bortolon A, Hughes JW, Spendlove JC, Wilks TM. Robust identification of multiple-input single-output system response for efficient pickup noise removal from tokamak diagnostics. Rev Sci Instrum 2022; 93:103503. [PMID: 36319373 DOI: 10.1063/5.0100988] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/27/2022] [Accepted: 08/04/2022] [Indexed: 06/16/2023]
Abstract
Electromagnetic pickup noise in the tokamak environment imposes an imminent challenge for measuring weak diagnostic photocurrents in the nA range. The diagnostic signal can be contaminated by an unknown mixture of crosstalk signals from coils powered by currents in the kA range. To address this issue, an algorithm for robust identification of linear multi-input single-output (MISO) systems has been developed. The MISO model describes the dynamic relationship between measured signals from power sources and observed signals in the diagnostic and allows for a precise subtraction of the noise component. The proposed method was tested on experimental diagnostic data from the DIII-D tokamak, and it has reduced noise by up to 20 dB in the 1-20 kHz range.
Collapse
Affiliation(s)
- T Odstrcil
- General Atomics, San Diego, California 92186-5608, USA
| | - F M Laggner
- Princeton Plasma Physics Laboratory, Princeton, New Jersey 08543, USA
| | - A M Rosenthal
- MIT Plasma Science and Fusion Center, Cambridge, Massachusetts 02139, USA
| | - A Bortolon
- Princeton Plasma Physics Laboratory, Princeton, New Jersey 08543, USA
| | - J W Hughes
- MIT Plasma Science and Fusion Center, Cambridge, Massachusetts 02139, USA
| | | | - T M Wilks
- MIT Plasma Science and Fusion Center, Cambridge, Massachusetts 02139, USA
| |
Collapse
|
10
|
Abstract
Primary cilia are slender cell-surface organelles that project into the intercellular space. In pancreatic beta cells, primary cilia coordinate a variety of cell responses including GPCR signaling, calcium influx, and insulin secretion, along with likely many underappreciated roles in islet development and differentiation. To study cilia function in islet biology, direct visualization of primary cilia by microscopic methods is often a necessary first step. Ciliary abundance, distribution, and morphology are heterogeneous among islet cells and are best visualized by fluorescence microscopy, the tools for which are readily accessible to most researchers. Here we present a collection of fluorescence imaging methods that we have adopted and optimized for the observation of primary cilia in mouse and human islets. These include conventional confocal microscopy using fixed islets and pancreas sections, live-cell imaging with cilia-targeted biosensors and probes, cilia motion recordings, and quantitative analysis of primary cilia waveform in the ex vivo environment. We discuss practical considerations and limitations of our approaches as well as new tools on the horizon to facilitate the observation of primary cilia in pancreatic islets.
Collapse
Affiliation(s)
- Zipeng A. Li
- Department of Medicine, Washington University School of Medicine, Saint Louis, MO, United States
| | - Jung Hoon Cho
- Department of Medicine, Washington University School of Medicine, Saint Louis, MO, United States
| | - Louis G. Woodhams
- Department of Mechanical Engineering and Materials Science, Washington University McKelvey School of Engineering, Saint Louis, MO, United States
| | - Jing W. Hughes
- Department of Medicine, Washington University School of Medicine, Saint Louis, MO, United States
| |
Collapse
|
11
|
Cho JH, Li ZA, Zhu L, Muegge BD, Roseman HF, Lee EY, Utterback T, Woodhams LG, Bayly PV, Hughes JW. Islet primary cilia motility controls insulin secretion. Sci Adv 2022; 8:eabq8486. [PMID: 36149960 PMCID: PMC9506710 DOI: 10.1126/sciadv.abq8486] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/04/2022] [Accepted: 07/13/2022] [Indexed: 06/16/2023]
Abstract
Primary cilia are specialized cell-surface organelles that mediate sensory perception and, in contrast to motile cilia and flagella, are thought to lack motility function. Here, we show that primary cilia in human and mouse pancreatic islets exhibit movement that is required for glucose-dependent insulin secretion. Islet primary cilia contain motor proteins conserved from those found in classic motile cilia, and their three-dimensional motion is dynein-driven and dependent on adenosine 5'-triphosphate and glucose metabolism. Inhibition of cilia motion blocks beta cell calcium influx and insulin secretion. Human beta cells have enriched ciliary gene expression, and motile cilia genes are altered in type 2 diabetes. Our findings redefine primary cilia as dynamic structures having both sensory and motile function and establish that pancreatic islet cilia movement plays a regulatory role in insulin secretion.
Collapse
Affiliation(s)
- Jung Hoon Cho
- Department of Medicine, Washington University School of Medicine, 660 South Euclid Ave, St. Louis, MO, USA
| | - Zipeng A. Li
- Department of Medicine, Washington University School of Medicine, 660 South Euclid Ave, St. Louis, MO, USA
| | - Lifei Zhu
- Department of Medicine, Washington University School of Medicine, 660 South Euclid Ave, St. Louis, MO, USA
| | - Brian D. Muegge
- Department of Medicine, Washington University School of Medicine, 660 South Euclid Ave, St. Louis, MO, USA
- Department of Medicine, VA Medical Center, 915 North Grand Blvd, St. Louis, MO, USA
| | - Henry F. Roseman
- Department of Medicine, Washington University School of Medicine, 660 South Euclid Ave, St. Louis, MO, USA
| | - Eun Young Lee
- Department of Medicine, Washington University School of Medicine, 660 South Euclid Ave, St. Louis, MO, USA
- Division of Endocrinology and Metabolism, Department of Internal Medicine, Seoul St. Mary’s Hospital, The Catholic University of Korea, Seoul, South Korea
| | - Toby Utterback
- Department of Mechanical Engineering and Materials Science, Washington University McKelvey School of Engineering, 1 Brookings Drive, St. Louis, MO, USA
| | - Louis G. Woodhams
- Department of Mechanical Engineering and Materials Science, Washington University McKelvey School of Engineering, 1 Brookings Drive, St. Louis, MO, USA
| | - Philip V. Bayly
- Department of Mechanical Engineering and Materials Science, Washington University McKelvey School of Engineering, 1 Brookings Drive, St. Louis, MO, USA
| | - Jing W. Hughes
- Department of Medicine, Washington University School of Medicine, 660 South Euclid Ave, St. Louis, MO, USA
| |
Collapse
|
12
|
Mathews A, Terry JL, Baek SG, Hughes JW, Kuang AQ, LaBombard B, Miller MA, Stotler D, Reiter D, Zholobenko W, Goto M. Deep modeling of plasma and neutral fluctuations from gas puff turbulence imaging. Rev Sci Instrum 2022; 93:063504. [PMID: 35778003 DOI: 10.1063/5.0088216] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/14/2022] [Accepted: 05/17/2022] [Indexed: 06/15/2023]
Abstract
The role of turbulence in setting boundary plasma conditions is presently a key uncertainty in projecting to fusion energy reactors. To robustly diagnose edge turbulence, we develop and demonstrate a technique to translate brightness measurements of HeI line radiation into local plasma fluctuations via a novel integrated deep learning framework that combines neutral transport physics and collisional radiative theory for the 33D - 23P transition in atomic helium with unbounded correlation constraints between the electron density and temperature. The tenets for experimental validity are reviewed, illustrating that this turbulence analysis for ionized gases is transferable to both magnetized and unmagnetized environments with arbitrary geometries. Based on fast camera data on the Alcator C-Mod tokamak, we present the first two-dimensional time-dependent experimental measurements of the turbulent electron density, electron temperature, and neutral density, revealing shadowing effects in a fusion plasma using a single spectral line.
Collapse
Affiliation(s)
- A Mathews
- MIT Plasma Science and Fusion Center, Cambridge, Massachusetts 02139, USA
| | - J L Terry
- MIT Plasma Science and Fusion Center, Cambridge, Massachusetts 02139, USA
| | - S G Baek
- MIT Plasma Science and Fusion Center, Cambridge, Massachusetts 02139, USA
| | - J W Hughes
- MIT Plasma Science and Fusion Center, Cambridge, Massachusetts 02139, USA
| | - A Q Kuang
- MIT Plasma Science and Fusion Center, Cambridge, Massachusetts 02139, USA
| | - B LaBombard
- MIT Plasma Science and Fusion Center, Cambridge, Massachusetts 02139, USA
| | - M A Miller
- MIT Plasma Science and Fusion Center, Cambridge, Massachusetts 02139, USA
| | - D Stotler
- Princeton Plasma Physics Laboratory, Princeton, New Jersey 08540, USA
| | - D Reiter
- Institut für Laser- und Plasmaphysik, Heinrich-Heine-Universität, Düsseldorf, Nordrhein-Westfalen 40225, Germany
| | - W Zholobenko
- Max-Planck-Institut für Plasmaphysik, Garching, Bayern 85748, Germany
| | - M Goto
- National Institute for Fusion Science, Toki-shi, Gifu-ken 509-5292, Japan
| |
Collapse
|
13
|
Cho JH, Hughes JW. Cilia Action in Islets: Lessons From Mouse Models. Front Endocrinol (Lausanne) 2022; 13:922983. [PMID: 35813631 PMCID: PMC9260721 DOI: 10.3389/fendo.2022.922983] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/18/2022] [Accepted: 05/23/2022] [Indexed: 11/30/2022] Open
Abstract
Primary cilia as a signaling organelle have garnered recent attention as a regulator of pancreatic islet function. These rod-like sensors exist on all major islet endocrine cell types and transduce a variety of external cues, while dysregulation of cilia function contributes to the development of diabetes. The complex role of islet primary cilia has been examined using genetic deletion targeting various components of cilia. In this review, we summarize experimental models for the study of islet cilia and current understanding of mechanisms of cilia regulation of islet hormone secretion. Consensus from these studies shows that pancreatic cilia perturbation can cause both endocrine and exocrine defects that are relevant to human disease. We discuss future research directions that would further elucidate cilia action in distinct groups of islet cells, including paracrine and juxtacrine regulation, GPCR signaling, and endocrine-exocrine crosstalk.
Collapse
|
14
|
Mathews A, Francisquez M, Hughes JW, Hatch DR, Zhu B, Rogers BN. Uncovering turbulent plasma dynamics via deep learning from partial observations. Phys Rev E 2021; 104:025205. [PMID: 34525532 DOI: 10.1103/physreve.104.025205] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/10/2020] [Accepted: 07/26/2021] [Indexed: 06/13/2023]
Abstract
One of the most intensely studied aspects of magnetic confinement fusion is edge plasma turbulence which is critical to reactor performance and operation. Drift-reduced Braginskii two-fluid theory has for decades been widely applied to model boundary plasmas with varying success. Towards better understanding edge turbulence in both theory and experiment, we demonstrate that a physics-informed deep learning framework constrained by partial differential equations can accurately learn turbulent fields consistent with the two-fluid theory from partial observations of electron pressure which is not otherwise possible using conventional equilibrium models. This technique presents a paradigm for the advanced design of plasma diagnostics and validation of magnetized plasma turbulence theories in challenging thermonuclear environments.
Collapse
Affiliation(s)
- A Mathews
- MIT Plasma Science and Fusion Center, Cambridge, Massachusetts 02139, USA
| | - M Francisquez
- MIT Plasma Science and Fusion Center, Cambridge, Massachusetts 02139, USA
- Princeton Plasma Physics Laboratory, Princeton, New Jersey 08540, USA
| | - J W Hughes
- MIT Plasma Science and Fusion Center, Cambridge, Massachusetts 02139, USA
| | - D R Hatch
- Institute for Fusion Studies, University of Texas, Austin, Texas 78704, USA
| | - B Zhu
- Lawrence Livermore National Laboratory, Livermore, California 94550, USA
| | - B N Rogers
- Department of Physics and Astronomy, Dartmouth College, Hanover, New Hampshire 03755, USA
| |
Collapse
|
15
|
Chen X, Ruiz JR, Howard NT, Guttenfelder W, Candy J, Hughes JW, Granetz RS, White AE. Feasibility study for a high-k temperature fluctuation diagnostic based on soft x-ray imaging. Rev Sci Instrum 2021; 92:053537. [PMID: 34243288 DOI: 10.1063/5.0043819] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/11/2021] [Accepted: 04/09/2021] [Indexed: 06/13/2023]
Abstract
A new pseudolocal tomography algorithm is developed for soft X-ray(SXR) imaging measurements of the turbulent electron temperature fluctuations (δ Te) in tokamaks and stellarators. The algorithm overcomes the constraints of limited viewing ports on the vessel wall (viewing angle) and limited number of lines of sight (LOS). This is accomplished by increasing the number of LOS locally in a region of interest. Numerical modeling demonstrates that the wavenumber spectrum of the turbulence can be reliably reconstructed, with an acceptable number of viewing angles and LOS and suitable low SNR detectors. We conclude that a SXR imaging diagnostic for measurements of turbulent δ Te using a pseudolocal reconstruction algorithm is feasible.
Collapse
Affiliation(s)
- X Chen
- Plasma Science and Fusion Center, MIT, Cambridge, Massachusetts 02139, USA
| | - J Ruiz Ruiz
- Department of Physics, University of Oxford, Oxford OX1 3NP, United Kingdom
| | - N T Howard
- Plasma Science and Fusion Center, MIT, Cambridge, Massachusetts 02139, USA
| | - W Guttenfelder
- Princeton Plasma Physics Laboratory, Princeton, New Jersey 08536, USA
| | - J Candy
- General Atomics, San Diego, California 92127, USA
| | - J W Hughes
- Plasma Science and Fusion Center, MIT, Cambridge, Massachusetts 02139, USA
| | - R S Granetz
- Plasma Science and Fusion Center, MIT, Cambridge, Massachusetts 02139, USA
| | - A E White
- Plasma Science and Fusion Center, MIT, Cambridge, Massachusetts 02139, USA
| |
Collapse
|
16
|
Rosenthal AM, Hughes JW, Bortolon A, Laggner FM, Wilks TM, Vieira R, Leccacorvi R, Marmar E, Nagy A, Freeman C, Mauzey D. A 1D Lyman-alpha profile camera for plasma edge neutral studies on the DIII-D tokamak. Rev Sci Instrum 2021; 92:033523. [PMID: 33820041 DOI: 10.1063/5.0024115] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/04/2020] [Accepted: 02/11/2021] [Indexed: 06/12/2023]
Abstract
A one dimensional, absolutely calibrated pinhole camera system was installed on the DIII-D tokamak to measure edge Lyman-alpha (Ly-α) emission from hydrogen isotopes, which can be used to infer neutral density and ionization rate profiles. The system is composed of two cameras, each providing a toroidal fan of 20 lines of sight, viewing the plasma edge on the inboard and outboard side of DIII-D. The cameras' views lie in a horizontal plane 77 cm below the midplane. At its tangency radius, each channel provides a radial resolution of ∼2 cm full width at half maximum (FWHM) with a total coverage of 22 cm. Each camera consists of a rectangular pinhole, Ly-α reflective mirror, narrow-band Ly-α transmission filter, and a 20 channel AXUV photodetector. The combined mirror and transmission filter have a FWHM of 5 nm, centered near the Ly-α wavelength of 121.6 nm and is capable of rejecting significant, parasitic carbon-III (C-III) emission from intrinsic plasma impurities. To provide a high spatial resolution measurement in a compact footprint, the camera utilizes advanced engineering and manufacturing techniques including 3D printing, high stability mirror mounts, and a novel alignment procedure. Absolutely calibrated, spatially resolved Ly-α brightness measurements utilize a bright, isolated line with low parasitic surface reflections and enable quantitative comparison to modeling to study divertor neutral leakage, main chamber fueling, and radial particle transport.
Collapse
Affiliation(s)
- A M Rosenthal
- MIT Plasma Science and Fusion Center, Cambridge, Massachusetts 02139, USA
| | - J W Hughes
- MIT Plasma Science and Fusion Center, Cambridge, Massachusetts 02139, USA
| | - A Bortolon
- Princeton Plasma Physics Laboratory, Princeton, New Jersey 08543, USA
| | - F M Laggner
- Princeton Plasma Physics Laboratory, Princeton, New Jersey 08543, USA
| | - T M Wilks
- MIT Plasma Science and Fusion Center, Cambridge, Massachusetts 02139, USA
| | - R Vieira
- MIT Plasma Science and Fusion Center, Cambridge, Massachusetts 02139, USA
| | - R Leccacorvi
- MIT Plasma Science and Fusion Center, Cambridge, Massachusetts 02139, USA
| | - E Marmar
- MIT Plasma Science and Fusion Center, Cambridge, Massachusetts 02139, USA
| | - A Nagy
- Princeton Plasma Physics Laboratory, Princeton, New Jersey 08543, USA
| | - C Freeman
- Princeton Plasma Physics Laboratory, Princeton, New Jersey 08543, USA
| | - D Mauzey
- Princeton Plasma Physics Laboratory, Princeton, New Jersey 08543, USA
| |
Collapse
|
17
|
Laggner FM, Bortolon A, Rosenthal AM, Wilks TM, Hughes JW, Freeman C, Golfinopoulos T, Nagy A, Mauzey D, Shafer MW. Absolute calibration of the Lyman-α measurement apparatus at DIII-D. Rev Sci Instrum 2021; 92:033522. [PMID: 33820112 DOI: 10.1063/5.0038134] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/19/2020] [Accepted: 01/13/2021] [Indexed: 06/12/2023]
Abstract
The LLAMA (Lyman-Alpha Measurement Apparatus) diagnostic was recently installed on the DIII-D tokamak [Rosenthal et al., Rev. Sci. Instrum. (submitted) (2020)]. LLAMA is a pinhole camera system with a narrow band Bragg mirror, a bandpass interference filter, and an absolute extreme ultraviolet photodiode detector array, which measures the Ly-α brightness in the toroidal direction on the inboard, high field side (HFS) and outboard, low field side (LFS). This contribution presents a setup and a procedure for an absolute calibration near the Ly-α line at 121.6 nm. The LLAMA in-vacuum components are designed as a compact, transferable setup that can be mounted in an ex situ vacuum enclosure that is equipped with an absolutely calibrated Ly-α source. The spectral purity and stability of the Ly-α source are characterized using a vacuum ultraviolet spectrometer, while the Ly-α source brightness is measured by a NIST-calibrated photodiode. The non-uniform nature of the Ly-α source emission was overcome by performing a calibration procedure that scans the Ly-α source position and employs a numerical optimization to determine the emission pattern. Nominal and measured calibration factors are determined and compared, showing agreement within their uncertainties. A first conversion of the measured signal obtained from DIII-D indicates that the Ly-α brightness on the HFS and LFS is on the order of 1020 Ph sr-1 m-2 s-1. The established calibration setup and procedure will be regularly used to re-calibrate the LLAMA during DIII-D vents to monitor possible degradation of optical components and detectors.
Collapse
Affiliation(s)
- F M Laggner
- Princeton Plasma Physics Laboratory, Princeton, New Jersey 08543, USA
| | - A Bortolon
- Princeton Plasma Physics Laboratory, Princeton, New Jersey 08543, USA
| | - A M Rosenthal
- MIT Plasma Science and Fusion Center, Cambridge, Massachusetts 02139, USA
| | - T M Wilks
- MIT Plasma Science and Fusion Center, Cambridge, Massachusetts 02139, USA
| | - J W Hughes
- MIT Plasma Science and Fusion Center, Cambridge, Massachusetts 02139, USA
| | - C Freeman
- Princeton Plasma Physics Laboratory, Princeton, New Jersey 08543, USA
| | - T Golfinopoulos
- MIT Plasma Science and Fusion Center, Cambridge, Massachusetts 02139, USA
| | - A Nagy
- Princeton Plasma Physics Laboratory, Princeton, New Jersey 08543, USA
| | - D Mauzey
- Princeton Plasma Physics Laboratory, Princeton, New Jersey 08543, USA
| | - M W Shafer
- Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831, USA
| |
Collapse
|
18
|
Miranda MA, Carson C, St. Pierre CL, Macias‐Velasco JF, Hughes JW, Kunzmann M, Schmidt H, Wayhart JP, Lawson HA. Spontaneous restoration of functional β-cell mass in obese SM/J mice. Physiol Rep 2020; 8:e14573. [PMID: 33113267 PMCID: PMC7592878 DOI: 10.14814/phy2.14573] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/06/2020] [Accepted: 08/08/2020] [Indexed: 12/23/2022] Open
Abstract
Maintenance of functional β-cell mass is critical to preventing diabetes, but the physiological mechanisms that cause β-cell populations to thrive or fail in the context of obesity are unknown. High fat-fed SM/J mice spontaneously transition from hyperglycemic-obese to normoglycemic-obese with age, providing a unique opportunity to study β-cell adaptation. Here, we characterize insulin homeostasis, islet morphology, and β-cell function during SM/J's diabetic remission. As they resolve hyperglycemia, obese SM/J mice dramatically increase circulating and pancreatic insulin levels while improving insulin sensitivity. Immunostaining of pancreatic sections reveals that obese SM/J mice selectively increase β-cell mass but not α-cell mass. Obese SM/J mice do not show elevated β-cell mitotic index, but rather elevated α-cell mitotic index. Functional assessment of isolated islets reveals that obese SM/J mice increase glucose-stimulated insulin secretion, decrease basal insulin secretion, and increase islet insulin content. These results establish that β-cell mass expansion and improved β-cell function underlie the resolution of hyperglycemia, indicating that obese SM/J mice are a valuable tool for exploring how functional β-cell mass can be recovered in the context of obesity.
Collapse
Affiliation(s)
- Mario A. Miranda
- Department of GeneticsWashington University School of MedicineSaint LouisMOUSA
| | - Caryn Carson
- Department of GeneticsWashington University School of MedicineSaint LouisMOUSA
| | | | | | - Jing W. Hughes
- Department of MedicineWashington University School of MedicineSaint LouisMOUSA
| | - Marcus Kunzmann
- Department of GeneticsWashington University School of MedicineSaint LouisMOUSA
| | - Heather Schmidt
- Department of GeneticsWashington University School of MedicineSaint LouisMOUSA
| | - Jessica P. Wayhart
- Department of GeneticsWashington University School of MedicineSaint LouisMOUSA
| | - Heather A. Lawson
- Department of GeneticsWashington University School of MedicineSaint LouisMOUSA
| |
Collapse
|
19
|
Saintilan NJ, Selby D, Hughes JW, Schlatter D, Kolb J, Boyce A. Mineral separation protocol for accurate and precise rhenium-osmium (Re-Os) geochronology and sulphur isotope composition of individual sulphide species. MethodsX 2020; 7:100944. [PMID: 32566491 PMCID: PMC7298518 DOI: 10.1016/j.mex.2020.100944] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2020] [Accepted: 05/20/2020] [Indexed: 11/16/2022] Open
Abstract
A temporal framework for mineral deposits is essential when addressing the history of their formation and conceptualizing genetic models of their origin. This knowledge is critical to understand how crust-forming processes are related to metal accumulations at specific time and conditions of Earth evolution. To this end, high-precision absolute geochronology utilising the rhenium-osmium (Re-Os) radiometric system in specific sulphide minerals is becoming a method of choice. Here, we present a procedure to obtain mineral separates of individual sulphide species that may coexist within specific mineralized horizons in ore deposits. This protocol is based on preliminary petrographic and paragenetic investigations of sulphide and gangue minerals using reflected and transmitted light microscopy. Our approach emphasizes the key role of a stepwise use of a Frantz isodynamic separator to produce mineral separates of individual sulphide species that are subsequently processed for Re-Os and sulphur isotope geochemistry.•Detailed method and its graphical illustration modified from an original procedure introduced by [1], [2].•Quality control and validation of monophasic mineral separates made by microscopic investigations and qualitative analysis of aliquots embedded in epoxy mounts.•The present method, which contributed to the successful results presented in the co-publication by Saintilan et al. (2020), demonstrates why other studies reporting Re-Os isotope data for mixtures of sulphide minerals should be considered with caution.
Collapse
Affiliation(s)
- N J Saintilan
- Department of Earth Sciences, University of Durham, Durham DH1 3LE, United Kingdom.,Department of Earth Sciences, Institute of Geochemistry and Petrology, ETH Zürich, Clausiusstraße 25, 8092 Zürich, Switzerland
| | - D Selby
- Department of Earth Sciences, University of Durham, Durham DH1 3LE, United Kingdom.,State Key Laboratory of Geological Processes and Mineral Resources, School of Earth Resources, China University of Geosciences, Wuhan, China
| | - J W Hughes
- Department of Earth Sciences, University of Durham, Durham DH1 3LE, United Kingdom.,Bluejay Mining Plc, 2nd Floor, 7-9 Swallow Street, London, W1B 4DE, United Kingdom
| | - D Schlatter
- Helvetica Exploration Services GmbH, Carl-Spitteler-Strasse 100, 8053 Zürich, Switzerland
| | - J Kolb
- Department of Geochemistry and Economic Geology, Institute of Applied Geosciences, Karlsruhe Institute of Technology, Adenauerring 20b, 76131 Karlsruhe, Germany
| | - A Boyce
- Isotope Geoscience Unit, SUERC, Rankine Avenue, East Kilbride, Glasgow G75 0QF, United Kingdom
| |
Collapse
|
20
|
Hughes JW, Cho JH, Conway HE, DiGruccio MR, Ng XW, Roseman HF, Abreu D, Urano F, Piston DW. Primary cilia control glucose homeostasis via islet paracrine interactions. Proc Natl Acad Sci U S A 2020; 117:8912-8923. [PMID: 32253320 PMCID: PMC7184063 DOI: 10.1073/pnas.2001936117] [Citation(s) in RCA: 49] [Impact Index Per Article: 12.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022] Open
Abstract
Pancreatic islets regulate glucose homeostasis through coordinated actions of hormone-secreting cells. What underlies the function of the islet as a unit is the close approximation and communication among heterogeneous cell populations, but the structural mediators of islet cellular cross talk remain incompletely characterized. We generated mice specifically lacking β-cell primary cilia, a cellular organelle that has been implicated in regulating insulin secretion, and found that the β-cell cilia are required for glucose sensing, calcium influx, insulin secretion, and cross regulation of α- and δ-cells. Protein expression profiling in islets confirms perturbation in these cellular processes and reveals additional targets of cilia-dependent signaling. At the organism level, the deletion of β-cell cilia disrupts circulating hormone levels, impairs glucose homeostasis and fuel usage, and leads to the development of diabetes. Together, these findings demonstrate that primary cilia not only orchestrate β-cell-intrinsic activity but also mediate cross talk both within the islet and from islets to other metabolic tissues, thus providing a unique role of cilia in nutrient metabolism and insight into the pathophysiology of diabetes.
Collapse
Affiliation(s)
- Jing W Hughes
- Department of Medicine, Washington University School of Medicine, St. Louis, MO 63110;
| | - Jung Hoon Cho
- Department of Medicine, Washington University School of Medicine, St. Louis, MO 63110
| | - Hannah E Conway
- Department of Medicine, Washington University School of Medicine, St. Louis, MO 63110
| | - Michael R DiGruccio
- Department of Cell Biology and Physiology, Washington University School of Medicine, St. Louis, MO 63110
| | - Xue Wen Ng
- Department of Cell Biology and Physiology, Washington University School of Medicine, St. Louis, MO 63110
| | - Henry F Roseman
- Department of Medicine, Washington University School of Medicine, St. Louis, MO 63110
| | - Damien Abreu
- Department of Medicine, Washington University School of Medicine, St. Louis, MO 63110
| | - Fumihiko Urano
- Department of Medicine, Washington University School of Medicine, St. Louis, MO 63110
| | - David W Piston
- Department of Cell Biology and Physiology, Washington University School of Medicine, St. Louis, MO 63110
| |
Collapse
|
21
|
Hughes JW, Bao YK, Salam M, Joshi P, Kilpatrick CR, Juneja K, Nieves D, Bouhairie V, Jordan OJ, Blustein EC, Tobin GS, McGill JB. Late-Onset T1DM and Older Age Predict Risk of Additional Autoimmune Disease. Diabetes Care 2019; 42:32-38. [PMID: 30361208 PMCID: PMC6300704 DOI: 10.2337/dc18-1157] [Citation(s) in RCA: 26] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/26/2018] [Accepted: 10/02/2018] [Indexed: 02/03/2023]
Abstract
OBJECTIVE Type 1 diabetes (T1DM) is associated with other autoimmune diseases (AIDs), which may have serious health consequences. The epidemiology of AIDs in T1DM is not well defined in adults with T1DM. In this cross-sectional cohort study, we sought to characterize the incident ages and prevalence of AIDs in adults with T1DM across a wide age spectrum. RESEARCH DESIGN AND METHODS A total of 1,212 adults seen at the Washington University Diabetes Center from 2011 to 2018 provided informed consent for the collection of their age, sex, race, and disease onset data. We performed paired association analyses based on age at onset of T1DM. Multivariate logistic regression was used to evaluate the independent effects of sex, race, T1DM age of onset, and T1DM duration on the prevalence of an additional AID. RESULTS Mean ± SD age of T1DM onset was 21.2 ± 14.4 years. AID incidence and prevalence increased with age. Female sex strongly predicted AID risk. The most prevalent T1DM-associated AIDs were thyroid disease, collagen vascular diseases, and pernicious anemia. T1DM age of onset and T1DM duration predicted AID risk. Patients with late-onset T1DM after 30 years of age had higher risks of developing additional AIDs compared with patients with younger T1DM onset. CONCLUSIONS The prevalence of AIDs in patients with T1DM increases with age and female sex. Later onset of T1DM is an independent and significant risk factor for developing additional AIDs. Individuals who are diagnosed with T1DM at older ages, particularly women, should be monitored for other autoimmune conditions.
Collapse
Affiliation(s)
- Jing W Hughes
- Division of Endocrinology, Metabolism and Lipid Research, Washington University School of Medicine in St. Louis, St. Louis, MO
| | - Yicheng K Bao
- Division of Endocrinology, Metabolism and Lipid Research, Washington University School of Medicine in St. Louis, St. Louis, MO.,University of Missouri-Kansas City School of Medicine, Kansas City, MO
| | - Maamoun Salam
- Division of Endocrinology, Metabolism and Lipid Research, Washington University School of Medicine in St. Louis, St. Louis, MO
| | - Prajesh Joshi
- Division of Endocrinology, Metabolism and Lipid Research, Washington University School of Medicine in St. Louis, St. Louis, MO.,Mercy Hospital Northwest Arkansas and University of Arkansas for Medical Sciences Northwest Regional Campus, Fayetteville, AR
| | - C Rachel Kilpatrick
- Division of Endocrinology, Metabolism and Lipid Research, Washington University School of Medicine in St. Louis, St. Louis, MO.,Washington Regional Medical Center, Fayetteville, AR
| | - Kavita Juneja
- Division of Endocrinology, Metabolism and Lipid Research, Washington University School of Medicine in St. Louis, St. Louis, MO.,Gilead Sciences, Foster City, CA
| | - David Nieves
- Division of Endocrinology, Metabolism and Lipid Research, Washington University School of Medicine in St. Louis, St. Louis, MO.,Northwell Health Lenox Hill Hospital, New York, NY
| | - Victoria Bouhairie
- Division of Endocrinology, Metabolism and Lipid Research, Washington University School of Medicine in St. Louis, St. Louis, MO.,Novant Health, Charlotte, NC
| | - Olivia J Jordan
- Division of Endocrinology, Metabolism and Lipid Research, Washington University School of Medicine in St. Louis, St. Louis, MO.,Pritzker School of Medicine, The University of Chicago, Chicago, IL
| | - Erica C Blustein
- Division of Endocrinology, Metabolism and Lipid Research, Washington University School of Medicine in St. Louis, St. Louis, MO.,John Peter Smith Hospital, Fort Worth, TX
| | - Garry S Tobin
- Division of Endocrinology, Metabolism and Lipid Research, Washington University School of Medicine in St. Louis, St. Louis, MO
| | - Janet B McGill
- Division of Endocrinology, Metabolism and Lipid Research, Washington University School of Medicine in St. Louis, St. Louis, MO
| |
Collapse
|
22
|
Hughes JW, Ustione A, Lavagnino Z, Piston DW. Regulation of islet glucagon secretion: Beyond calcium. Diabetes Obes Metab 2018; 20 Suppl 2:127-136. [PMID: 30230183 PMCID: PMC6148361 DOI: 10.1111/dom.13381] [Citation(s) in RCA: 41] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/18/2018] [Revised: 05/03/2018] [Accepted: 05/23/2018] [Indexed: 12/19/2022]
Abstract
The islet of Langerhans plays a key role in glucose homeostasis through regulated secretion of the hormones insulin and glucagon. Islet research has focused on the insulin-secreting β-cells, even though aberrant glucagon secretion from α-cells also contributes to the aetiology of diabetes. Despite its importance, the mechanisms controlling glucagon secretion remain controversial. Proper α-cell function requires the islet milieu, where β- and δ-cells drive and constrain α-cell dynamics. The response of glucagon to glucose is similar between isolated islets and that measured in vivo, so it appears that the glucose dependence requires only islet-intrinsic factors and not input from blood flow or the nervous system. Elevated intracellular free Ca2+ is needed for α-cell exocytosis, but interpreting Ca2+ data is tricky since it is heterogeneous among α-cells at all physiological glucose levels. Total Ca2+ activity in α-cells increases slightly with glucose, so Ca2+ may serve a permissive, rather than regulatory, role in glucagon secretion. On the other hand, cAMP is a more promising candidate for controlling glucagon secretion and is itself driven by paracrine signalling from β- and δ-cells. Another pathway, juxtacrine signalling through the α-cell EphA receptors, stimulated by β-cell ephrin ligands, leads to a tonic inhibition of glucagon secretion. We discuss potential combinations of Ca2+ , cAMP, paracrine and juxtacrine factors in the regulation of glucagon secretion, focusing on recent data in the literature that might unify the field towards a quantitative understanding of α-cell function.
Collapse
Affiliation(s)
- Jing W. Hughes
- Division of Endocrinology, Metabolism, and Lipid Research, Department of Medicine, Washington University School of Medicine, St. Louis, Missouri
| | - Alessandro Ustione
- Department of Cell Biology and Physiology, Washington University School of Medicine, St. Louis, Missouri
| | - Zeno Lavagnino
- Department of Cell Biology and Physiology, Washington University School of Medicine, St. Louis, Missouri
| | - David W. Piston
- Department of Cell Biology and Physiology, Washington University School of Medicine, St. Louis, Missouri
| |
Collapse
|
23
|
Baek SG, Wallace GM, Bonoli PT, Brunner D, Faust IC, Hubbard AE, Hughes JW, LaBombard B, Parker RR, Porkolab M, Shiraiwa S, Wukitch S. Observation of Efficient Lower Hybrid Current Drive at High Density in Diverted Plasmas on the Alcator C-Mod Tokamak. Phys Rev Lett 2018; 121:055001. [PMID: 30118250 DOI: 10.1103/physrevlett.121.055001] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/09/2018] [Revised: 06/22/2018] [Indexed: 06/08/2023]
Abstract
Efficient lower hybrid current drive (LHCD) is demonstrated at densities up to n[over ¯]_{e}≈1.5×10^{20} m^{-3} in diverted plasmas on the Alcator C-Mod tokamak by operating at increased plasma current-and therefore reduced Greenwald density fraction. This density exceeds the nominal "LH density limit" at n[over ¯]_{e}≈1.0×10^{20} m^{-3} reported previously, above which an anomalous loss of current drive efficiency was observed. The recovery of current drive efficiency to a level consistent with engineering scalings is correlated with a reduction in density shoulders and turbulence levels in the far scrape-off layer. Concurrently, rf wave interaction with the edge and/or scrape-off-layer plasma is reduced, as indicated by a minimal broadening of the wave frequency spectrum measured at the plasma edge. These results have important implications for sustaining steady-state tokamak operation and indicate a pathway forward for implementing efficient LHCD in a reactor.
Collapse
Affiliation(s)
- S G Baek
- MIT Plasma Science and Fusion Center, Cambridge, Massachusetts 02139, USA
| | - G M Wallace
- MIT Plasma Science and Fusion Center, Cambridge, Massachusetts 02139, USA
| | - P T Bonoli
- MIT Plasma Science and Fusion Center, Cambridge, Massachusetts 02139, USA
| | - D Brunner
- MIT Plasma Science and Fusion Center, Cambridge, Massachusetts 02139, USA
| | - I C Faust
- MIT Plasma Science and Fusion Center, Cambridge, Massachusetts 02139, USA
- Max Planck Institute for Plasma Physics, Munich, Bavaria 85748, Germany
| | - A E Hubbard
- MIT Plasma Science and Fusion Center, Cambridge, Massachusetts 02139, USA
| | - J W Hughes
- MIT Plasma Science and Fusion Center, Cambridge, Massachusetts 02139, USA
| | - B LaBombard
- MIT Plasma Science and Fusion Center, Cambridge, Massachusetts 02139, USA
| | - R R Parker
- MIT Plasma Science and Fusion Center, Cambridge, Massachusetts 02139, USA
| | - M Porkolab
- MIT Plasma Science and Fusion Center, Cambridge, Massachusetts 02139, USA
| | - S Shiraiwa
- MIT Plasma Science and Fusion Center, Cambridge, Massachusetts 02139, USA
| | - S Wukitch
- MIT Plasma Science and Fusion Center, Cambridge, Massachusetts 02139, USA
| |
Collapse
|
24
|
Hughes JW, Muegge BD, Tobin GS, Litvin M, Sun L, Saenz JB, Gyawali CP, McGill JB. HIGH-RISK GASTRIC PATHOLOGY AND PREVALENT AUTOIMMUNE DISEASES IN PATIENTS WITH PERNICIOUS ANEMIA. Endocr Pract 2018; 23:1297-1303. [PMID: 29190137 DOI: 10.4158/ep-2017-0056] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
OBJECTIVE Pernicious anemia (PA) develops from atrophic gastritis due to autoimmune destruction of parietal cells and results in achlorhydria, vitamin B12 and iron deficiencies, anemia, neurologic deficits, and premalignant and malignant stomach lesions. We report the presentation, diagnosis and gastric complications of PA in patients from an endocrinology practice. METHODS Thirty-four patients (31 female, 3 male) with PA who underwent esophagogastroduodenoscopy (EGD) or gastrectomy were identified. Pertinent clinical, laboratory, and pathology findings were reviewed and summarized. RESULTS The mean age of patients was 58.6 ± 14.2 years; the onset of PA was age 50.2 ± 15.3 years. Anemia reflected vitamin B12 and/or iron deficiencies. Parietal cell antibodies (PCA) were detected in 97% of patients, and intrinsic factor blocking antibody (IFBA) was found in 52%. Fasting gastrin and chromogranin A levels were elevated (1,518.0 ± 1,588.3 pg/mL, and 504.9.1 ± 1,524.9 ng/mL respectively). Autoimmune or immunologic diseases (AIDs) were present in 32/34 patients. Stomach pathology showed premalignant or malignant lesions in 26 patients, including gastric neuroendocrine tumors (GNETs) in 6 and adenocarcinoma in 1. One patient presented with neurologic symptoms and subacute combined degeneration of the posterior column of the spinal cord. CONCLUSION PA should be suspected in patients with unexplained anemia or neurologic symptoms. The diagnosis of PA relies on fasting gastrin and gastric auto-antibody testing, in addition to hematologic evaluation. EGD with measurement of gastric pH and biopsies of the fundus and antrum identifies patients with achlorhydria, atrophic gastritis, and premalignant and malignant stomach lesions. EGD surveillance of patients with high-risk stomach lesions is recommended. ABBREVIATIONS AID = autoimmune or immunologic disease; EGD = esophagogastroduodenoscopy; GNET = gastric neuroendocrine tumor; IFBA = intrinsic factor blocking antibody; PA = pernicious anemia; PCA = parietal cell antibody; T1D = type 1 diabetes.
Collapse
|
25
|
Chang CS, Ku S, Tynan GR, Hager R, Churchill RM, Cziegler I, Greenwald M, Hubbard AE, Hughes JW. Fast Low-to-High Confinement Mode Bifurcation Dynamics in a Tokamak Edge Plasma Gyrokinetic Simulation. Phys Rev Lett 2017; 118:175001. [PMID: 28498701 DOI: 10.1103/physrevlett.118.175001] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/05/2016] [Indexed: 06/07/2023]
Abstract
Transport barrier formation and its relation to sheared flows in fluids and plasmas are of fundamental interest in various natural and laboratory observations and of critical importance in achieving an economical energy production in a magnetic fusion device. Here we report the first observation of an edge transport barrier formation event in an electrostatic gyrokinetic simulation carried out in a realistic diverted tokamak edge geometry under strong forcing by a high rate of heat deposition. The results show that turbulent Reynolds-stress-driven sheared E×B flows act in concert with neoclassical orbit loss to quench turbulent transport and form a transport barrier just inside the last closed magnetic flux surface.
Collapse
Affiliation(s)
- C S Chang
- Princeton Plasma Physics Laboratory, Princeton, New Jersey 08540, USA
| | - S Ku
- Princeton Plasma Physics Laboratory, Princeton, New Jersey 08540, USA
| | - G R Tynan
- University of California San Diego, La Jolla, California 92093, USA
| | - R Hager
- Princeton Plasma Physics Laboratory, Princeton, New Jersey 08540, USA
| | - R M Churchill
- Princeton Plasma Physics Laboratory, Princeton, New Jersey 08540, USA
| | - I Cziegler
- University of California San Diego, La Jolla, California 92093, USA
| | - M Greenwald
- MIT Plasma Science and Fusion Center, Cambridge, Massachusetts 02139, USA
| | - A E Hubbard
- MIT Plasma Science and Fusion Center, Cambridge, Massachusetts 02139, USA
| | - J W Hughes
- MIT Plasma Science and Fusion Center, Cambridge, Massachusetts 02139, USA
| |
Collapse
|
26
|
Cziegler I, Hubbard AE, Hughes JW, Terry JL, Tynan GR. Turbulence Nonlinearities Shed Light on Geometric Asymmetry in Tokamak Confinement Transitions. Phys Rev Lett 2017; 118:105003. [PMID: 28339277 DOI: 10.1103/physrevlett.118.105003] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/01/2016] [Indexed: 06/06/2023]
Abstract
A comprehensive study of fully frequency-resolved nonlinear kinetic energy transfer has been performed for the first time in a diverted tokamak, providing new insight into the parametric dependences of edge turbulence transitions. Measurements using gas puff imaging in the turbulent L-mode state illuminate the source of the long known but as yet unexplained "favorable-unfavorable" geometric asymmetry of the power threshold for transition to the turbulence-suppressed H mode. Results from the recently discovered I mode point to a competition between zonal flow (ZF) and geodesic-acoustic modes (GAM) for turbulent energy, while showing new evidence that the I-to-H transition is still dominated by ZFs. The availability of nonlinear drive for the GAM against net heat flux through the edge corresponds very well to empirical scalings found experimentally for accessing the I mode.
Collapse
Affiliation(s)
- I Cziegler
- York Plasma Institute, Department of Physics, University of York, Heslington YO10 5DD, United Kingdom
| | - A E Hubbard
- Plasma Science and Fusion Center, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, USA
| | - J W Hughes
- Plasma Science and Fusion Center, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, USA
| | - J L Terry
- Plasma Science and Fusion Center, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, USA
| | - G R Tynan
- University of California San Diego, La Jolla, California 92093, USA
| |
Collapse
|
27
|
Hughes JW, Riddlesworth TD, DiMeglio LA, Miller KM, Rickels MR, McGill JB. Autoimmune Diseases in Children and Adults With Type 1 Diabetes From the T1D Exchange Clinic Registry. J Clin Endocrinol Metab 2016; 101:4931-4937. [PMID: 27676394 PMCID: PMC7530541 DOI: 10.1210/jc.2016-2478] [Citation(s) in RCA: 57] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
BACKGROUND AND AIMS Type 1 diabetes (T1D) is associated with other autoimmune diseases (AIDs), but the prevalence and associated predictive factors for these comorbidities of T1D across all age groups have not been fully characterized. MATERIALS AND METHODS Data obtained from 25 759 participants with T1D enrolled in the T1D Exchange Registry were used to analyze the types and frequency of AIDs as well as their relationships to gender, age, and race/ethnicity. Diagnoses of autoimmune diseases, represented as ordinal categories (0, 1, 2, 3, or more AIDs) were obtained from medical records of Exchange Registry participants. RESULTS Among the 25 759 T1D Exchange participants, 50% were female, 82% non-Hispanic white, mean age was 23.0 ± 16.9 years and mean duration of diabetes was 11 years. Of these participants, 6876 (27%) were diagnosed with at least one AID. Frequency of two or more AIDs increased from 4.3% in participants aged younger than 13 years to 10.4% in those aged 50 years or older. The most common AIDs were thyroid (6097, 24%), gastrointestinal (1530, 6%), and collagen vascular diseases (432, 2%). Addison's disease was rare (75, 0.3%). The prevalence of one or more AIDs was increased in females and non-Hispanic whites and with older age. CONCLUSIONS In the T1D Exchange Clinic Registry, a diagnosis of one or more AIDs in addition to T1D is common, particularly in women, non-Hispanic whites, and older individuals. Results of this study have implications for both primary care and endocrine practice and will allow clinicians to better anticipate and manage the additional AIDs that develop in patients with T1D.
Collapse
Affiliation(s)
- Jing W Hughes
- Department of Medicine, Washington University School of Medicine (J.W.H., J.B.M.), St Louis, Missouri 63110; Jaeb Center for Health Research (T.D.R., K.M.M.), Tampa, Florida 33647; Department of Pediatrics, Indiana University School of Medicine (L.A.D.), Indianapolis, Indiana 46202; and Department of Medicine, Perelman School of Medicine (M.R.R.) University of Pennsylvania, Philadelphia, Pennsylvania 19104
| | - Tonya D Riddlesworth
- Department of Medicine, Washington University School of Medicine (J.W.H., J.B.M.), St Louis, Missouri 63110; Jaeb Center for Health Research (T.D.R., K.M.M.), Tampa, Florida 33647; Department of Pediatrics, Indiana University School of Medicine (L.A.D.), Indianapolis, Indiana 46202; and Department of Medicine, Perelman School of Medicine (M.R.R.) University of Pennsylvania, Philadelphia, Pennsylvania 19104
| | - Linda A DiMeglio
- Department of Medicine, Washington University School of Medicine (J.W.H., J.B.M.), St Louis, Missouri 63110; Jaeb Center for Health Research (T.D.R., K.M.M.), Tampa, Florida 33647; Department of Pediatrics, Indiana University School of Medicine (L.A.D.), Indianapolis, Indiana 46202; and Department of Medicine, Perelman School of Medicine (M.R.R.) University of Pennsylvania, Philadelphia, Pennsylvania 19104
| | - Kellee M Miller
- Department of Medicine, Washington University School of Medicine (J.W.H., J.B.M.), St Louis, Missouri 63110; Jaeb Center for Health Research (T.D.R., K.M.M.), Tampa, Florida 33647; Department of Pediatrics, Indiana University School of Medicine (L.A.D.), Indianapolis, Indiana 46202; and Department of Medicine, Perelman School of Medicine (M.R.R.) University of Pennsylvania, Philadelphia, Pennsylvania 19104
| | - Michael R Rickels
- Department of Medicine, Washington University School of Medicine (J.W.H., J.B.M.), St Louis, Missouri 63110; Jaeb Center for Health Research (T.D.R., K.M.M.), Tampa, Florida 33647; Department of Pediatrics, Indiana University School of Medicine (L.A.D.), Indianapolis, Indiana 46202; and Department of Medicine, Perelman School of Medicine (M.R.R.) University of Pennsylvania, Philadelphia, Pennsylvania 19104
| | - Janet B McGill
- Department of Medicine, Washington University School of Medicine (J.W.H., J.B.M.), St Louis, Missouri 63110; Jaeb Center for Health Research (T.D.R., K.M.M.), Tampa, Florida 33647; Department of Pediatrics, Indiana University School of Medicine (L.A.D.), Indianapolis, Indiana 46202; and Department of Medicine, Perelman School of Medicine (M.R.R.) University of Pennsylvania, Philadelphia, Pennsylvania 19104
| | -
- Department of Medicine, Washington University School of Medicine (J.W.H., J.B.M.), St Louis, Missouri 63110; Jaeb Center for Health Research (T.D.R., K.M.M.), Tampa, Florida 33647; Department of Pediatrics, Indiana University School of Medicine (L.A.D.), Indianapolis, Indiana 46202; and Department of Medicine, Perelman School of Medicine (M.R.R.) University of Pennsylvania, Philadelphia, Pennsylvania 19104
| |
Collapse
|
28
|
Hughes JW, Wyckoff JA, Hollander AS, Derdeyn CP, McGill JB. Moyamoya syndrome causing stroke in young women with type 1 diabetes. J Diabetes Complications 2016; 30:1640-1642. [PMID: 27592246 PMCID: PMC5050134 DOI: 10.1016/j.jdiacomp.2016.08.004] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/28/2016] [Accepted: 08/06/2016] [Indexed: 11/30/2022]
Abstract
CONTEXT Moyamoya syndrome is an idiopathic brain vasculopathy characterized by stenosis of major intracranial arteries. It often presents in patients with type 1 diabetes or thyroid disease and may have an autoimmune etiology. Moyamoya-related stroke poses a diagnostic challenge as initial symptoms and deficits vary greatly from classic ischemic stroke to encephalopathy, psychiatric, or seizure disorder. CASE DESCRIPTION We report 4 patients with type 1 diabetes and other autoimmune diseases who developed moyamoya-related stroke at a young age. Despite having long-term diabetes, these patients exhibited no evidence of dyslipidemia or other typical risk factors for atherosclerosis which might contribute to premature stroke. Three of the four patients underwent revascularization surgery while one patient received conservative management. All patients had improved neurologic function after treatment, some with residual deficits. CONCLUSION We highlight the importance of recognizing moyamoya syndrome in patients with pre-existing autoimmune diseases such as type 1 diabetes, as prompt diagnosis and treatment can have major impact on patient outcome and quality of life.
Collapse
Affiliation(s)
- Jing W Hughes
- Division of Endocrinology, Metabolism and Lipid Research, Department of Medicine, Washington University School of Medicine, St. Louis, MO, USA.
| | - Jennifer A Wyckoff
- Division of Metabolism, Endocrinology, and Diabetes, Department of Internal Medicine, University of Michigan Health System, Ann Arbor, MI, USA
| | - Abby S Hollander
- Division of Pediatric Endocrinology and Metabolism, Washington University School of Medicine, St. Louis, MO, USA
| | - Colin P Derdeyn
- Division of Diagnostic Radiology, Neuroradiology Section, Washington University School of Medicine, St. Louis, MO, USA
| | - Janet B McGill
- Division of Endocrinology, Metabolism and Lipid Research, Department of Medicine, Washington University School of Medicine, St. Louis, MO, USA
| |
Collapse
|
29
|
Houshmandyar S, Yang ZJ, Phillips PE, Rowan WL, Hubbard AE, Rice JE, Hughes JW, Wolfe SM. Temperature gradient scale length measurement: A high accuracy application of electron cyclotron emission without calibration. Rev Sci Instrum 2016; 87:11E101. [PMID: 27910677 DOI: 10.1063/1.4955297] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
Calibration is a crucial procedure in electron temperature (Te) inference from a typical electron cyclotron emission (ECE) diagnostic on tokamaks. Although the calibration provides an important multiplying factor for an individual ECE channel, the parameter ΔTe/Te is independent of any calibration. Since an ECE channel measures the cyclotron emission for a particular flux surface, a non-perturbing change in toroidal magnetic field changes the view of that channel. Hence the calibration-free parameter is a measure of Te gradient. BT-jog technique is presented here which employs the parameter and the raw ECE signals for direct measurement of electron temperature gradient scale length.
Collapse
Affiliation(s)
- S Houshmandyar
- Institute for Fusion Studies, The University of Texas at Austin, Austin, Texas 78712, USA
| | - Z J Yang
- Huazhong University of Science and Technology, Wuhan, Hubei 430074, China
| | - P E Phillips
- Institute for Fusion Studies, The University of Texas at Austin, Austin, Texas 78712, USA
| | - W L Rowan
- Institute for Fusion Studies, The University of Texas at Austin, Austin, Texas 78712, USA
| | - A E Hubbard
- Plasma Science and Fusion Center, Massachusetts Institute of Technology, Cambridge, Massachusetts 02129, USA
| | - J E Rice
- Plasma Science and Fusion Center, Massachusetts Institute of Technology, Cambridge, Massachusetts 02129, USA
| | - J W Hughes
- Plasma Science and Fusion Center, Massachusetts Institute of Technology, Cambridge, Massachusetts 02129, USA
| | - S M Wolfe
- Plasma Science and Fusion Center, Massachusetts Institute of Technology, Cambridge, Massachusetts 02129, USA
| |
Collapse
|
30
|
Diallo A, Hughes JW, Greenwald M, Labombard B, Davis E, Baek SG, Theiler C, Snyder P, Canik J, Walk J, Golfinopoulos T, Terry J, Churchill M, Hubbard A, Porkolab M, Delgado-Aparicio L, Reinke ML, White A. Observation of edge instability limiting the pedestal growth in tokamak plasmas. Phys Rev Lett 2014; 112:115001. [PMID: 24702380 DOI: 10.1103/physrevlett.112.115001] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/15/2013] [Indexed: 06/03/2023]
Abstract
With fusion device performance hinging on the edge pedestal pressure, it is imperative to experimentally understand the physical mechanism dictating the pedestal characteristics and to validate and improve pedestal predictive models. This Letter reports direct evidence of density and magnetic fluctuations showing the stiff onset of an edge instability leading to the saturation of the pedestal on the Alcator C-Mod tokamak. Edge stability analyses indicate that the pedestal is unstable to both ballooning mode and kinetic ballooning mode in agreement with observations.
Collapse
Affiliation(s)
- A Diallo
- Princeton Plasma Physics Laboratory, Princeton, New Jersey 08543, USA
| | - J W Hughes
- Plasma Science and Fusion Center, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, USA
| | - M Greenwald
- Plasma Science and Fusion Center, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, USA
| | - B Labombard
- Plasma Science and Fusion Center, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, USA
| | - E Davis
- Plasma Science and Fusion Center, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, USA
| | - S-G Baek
- Plasma Science and Fusion Center, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, USA
| | - C Theiler
- Plasma Science and Fusion Center, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, USA
| | - P Snyder
- General Atomics, San Diego, California 92186, USA
| | - J Canik
- Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831, USA
| | - J Walk
- Plasma Science and Fusion Center, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, USA
| | - T Golfinopoulos
- Plasma Science and Fusion Center, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, USA
| | - J Terry
- Plasma Science and Fusion Center, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, USA
| | - M Churchill
- Plasma Science and Fusion Center, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, USA
| | - A Hubbard
- Plasma Science and Fusion Center, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, USA
| | - M Porkolab
- Plasma Science and Fusion Center, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, USA
| | | | - M L Reinke
- Plasma Science and Fusion Center, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, USA
| | - A White
- Plasma Science and Fusion Center, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, USA
| |
Collapse
|
31
|
Rice JE, Podpaly YA, Reinke ML, Mumgaard R, Scott SD, Shiraiwa S, Wallace GM, Chouli B, Fenzi-Bonizec C, Nave MFF, Diamond PH, Gao C, Granetz RS, Hughes JW, Parker RR, Bonoli PT, Delgado-Aparicio L, Eriksson LG, Giroud C, Greenwald MJ, Hubbard AE, Hutchinson IH, Irby JH, Kirov K, Mailloux J, Marmar ES, Wolfe SM. Effects of magnetic shear on toroidal rotation in tokamak plasmas with lower hybrid current drive. Phys Rev Lett 2013; 111:125003. [PMID: 24093268 DOI: 10.1103/physrevlett.111.125003] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/24/2013] [Indexed: 06/02/2023]
Abstract
Application of lower hybrid (LH) current drive in tokamak plasmas can induce both co- and countercurrent directed changes in toroidal rotation, depending on the core q profile. For discharges with q(0) <1, rotation increments in the countercurrent direction are observed. If the LH-driven current is sufficient to suppress sawteeth and increase q(0) above unity, the core toroidal rotation change is in the cocurrent direction. This change in sign of the rotation increment is consistent with a change in sign of the residual stress (the divergence of which constitutes an intrinsic torque that drives the flow) through its dependence on magnetic shear.
Collapse
Affiliation(s)
- J E Rice
- PSFC MIT, Cambridge, Massachusetts 02139, USA
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
32
|
Hughes JW, Guess MK, Hittelman A, Yip S, Astle J, Pal L, Inzucchi SE, Dulay AT. Clitoral epidermoid cyst presenting as pseudoclitoromegaly of pregnancy. AJP Rep 2013; 3:57-62. [PMID: 23943712 PMCID: PMC3699154 DOI: 10.1055/s-0033-1334461] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/04/2012] [Accepted: 01/02/2013] [Indexed: 11/09/2022] Open
Abstract
Objective Acquired clitoromegaly is rare and may result from hormonal and nonhormonal causes, and evaluation of the pregnant patient with clitoromegaly invokes a specific set of differential diagnoses. Methods Case report. Results We describe the case of a young woman with pregnancy-associated clitoral enlargement whose hormonal evaluation proved negative. Further investigation concluded that an epidermoid cyst was the culprit of her pseudoclitoromegaly. The patient underwent successful surgical resection and has had no recurrence at her subsequent pregnancy. Conclusion We review the differential diagnosis of clitoromegaly, including hormonal and nonhormonal causes, with focus on the evaluation of pregnancy-associated clitoromegaly.
Collapse
Affiliation(s)
- Jing W Hughes
- Section of Endocrinology and Metabolism, Yale University School of Medicine, New Haven, Connecticut
| | | | | | | | | | | | | | | |
Collapse
|
33
|
Delgado-Aparicio L, Sugiyama L, Granetz R, Gates DA, Rice JE, Reinke ML, Bitter M, Fredrickson E, Gao C, Greenwald M, Hill K, Hubbard A, Hughes JW, Marmar E, Pablant N, Podpaly Y, Scott S, Wilson R, Wolfe S, Wukitch S. Formation and stability of impurity "snakes" in tokamak plasmas. Phys Rev Lett 2013; 110:065006. [PMID: 23432265 DOI: 10.1103/physrevlett.110.065006] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/02/2012] [Indexed: 06/01/2023]
Abstract
New observations of the formation and dynamics of long-lived impurity-induced helical "snake" modes in tokamak plasmas have recently been carried out on Alcator C-Mod. The snakes form as an asymmetry in the impurity ion density that undergoes a seamless transition from a small helically displaced density to a large crescent-shaped helical structure inside q<1, with a regularly sawtoothing core. The observations show that the conditions for the formation and persistence of a snake cannot be explained by plasma pressure alone. Instead, many features arise naturally from nonlinear interactions in a 3D MHD model that separately evolves the plasma density and temperature.
Collapse
|
34
|
Rice JE, Cziegler I, Diamond PH, Duval BP, Podpaly YA, Reinke ML, Ennever PC, Greenwald MJ, Hughes JW, Ma Y, Marmar ES, Porkolab M, Tsujii N, Wolfe SM. Rotation reversal bifurcation and energy confinement saturation in tokamak Ohmic L-mode plasmas. Phys Rev Lett 2011; 107:265001. [PMID: 22243160 DOI: 10.1103/physrevlett.107.265001] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/10/2011] [Indexed: 05/31/2023]
Abstract
Direction reversals of intrinsic toroidal rotation have been observed in diverted Alcator C-Mod Ohmic L-mode plasmas following electron density ramps. For low density discharges, the core rotation is directed cocurrent, and reverses to countercurrent following an increase in the density above a certain threshold. Such reversals occur together with a decrease in density fluctuations with 2 cm(-1)≤k(θ)≤11 cm(-1) and frequencies above 70 kHz. There is a strong correlation between the reversal density and the density at which the Ohmic L-mode energy confinement changes from the linear to the saturated regime.
Collapse
Affiliation(s)
- J E Rice
- Plasma Science & Fusion Center (PSFC), Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, USA
| | | | | | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
35
|
Rice JE, Hughes JW, Diamond PH, Kosuga Y, Podpaly YA, Reinke ML, Greenwald MJ, Gürcan ÖD, Hahm TS, Hubbard AE, Marmar ES, McDevitt CJ, Whyte DG. Edge temperature gradient as intrinsic rotation drive in Alcator C-Mod tokamak plasmas. Phys Rev Lett 2011; 106:215001. [PMID: 21699305 DOI: 10.1103/physrevlett.106.215001] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/02/2010] [Indexed: 05/31/2023]
Abstract
Intrinsic rotation has been observed in I-mode plasmas from the C-Mod tokamak, and is found to be similar to that in H mode, both in its edge origin and in the scaling with global pressure. Since both plasmas have similar edge ∇T, but completely different edge ∇n, it may be concluded that the drive of the intrinsic rotation is the edge ∇T rather than ∇P. Evidence suggests that the connection between gradients and rotation is the residual stress, and a scaling for the rotation from conversion of free energy to macroscopic flow is calculated.
Collapse
Affiliation(s)
- J E Rice
- PSFC, MIT, Cambridge, Massachusetts 02139, USA
| | | | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
36
|
Ince-Cushman A, Rice JE, Reinke M, Greenwald M, Wallace G, Parker R, Fiore C, Hughes JW, Bonoli P, Shiraiwa S, Hubbard A, Wolfe S, Hutchinson IH, Marmar E, Bitter M, Wilson J, Hill K. Observation of self-generated flows in tokamak plasmas with lower-hybrid-driven current. Phys Rev Lett 2009; 102:035002. [PMID: 19257362 DOI: 10.1103/physrevlett.102.035002] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/27/2008] [Indexed: 05/27/2023]
Abstract
In Alcator C-Mod discharges lower hybrid waves have been shown to induce a countercurrent change in toroidal rotation of up to 60 km/s in the central region of the plasma (r/a approximately <0.4). This modification of the toroidal rotation profile develops on a time scale comparable to the current redistribution time (approximately 100 ms) but longer than the energy and momentum confinement times (approximately 20 ms). A comparison of the co- and countercurrent injected waves indicates that current drive (as opposed to heating) is responsible for the rotation profile modifications. Furthermore, the changes in central rotation velocity induced by lower hybrid current drive (LHCD) are well correlated with changes in normalized internal inductance. The application of LHCD has been shown to generate sheared rotation profiles and a negative increment in the radial electric field profile consistent with a fast electron pinch.
Collapse
Affiliation(s)
- A Ince-Cushman
- Plasma Science and Fusion Center, Massachusetts Institute of Technology, 77 Massachusetts Avenue, NW16, Cambridge, Massachusetts 02139, USA
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
37
|
|
38
|
|
39
|
|
40
|
Ward WR, Hughes JW, Faull WB, Cripps PJ, Sutherland JP, Sutherst JE. Observational study of temperature, moisture, pH and bacteria in straw bedding, and faecal consistency, cleanliness and mastitis in cows in four dairy herds. Vet Rec 2002; 151:199-206. [PMID: 12211391 DOI: 10.1136/vr.151.7.199] [Citation(s) in RCA: 62] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Abstract
A study of four dairy farms showed that much of the straw stored for bedding was too wet (over 15 per cent moisture content). Most of the beds, including their top surfaces, were damp (above 75 per cent relative humidity). The temperature of the surface of most of the straw beds was related to the air temperature, many being below 15 degrees C, but below the surface the temperatures of most beds reached between 15 degrees C and 45 degrees C within about a week of their being renewed. Bacterial counts also reached a plateau within one to two weeks. The pH of the top layers of straw was usually between 8.5 and 9.5. Adding lime daily to the top layer of the straw failed to raise the pH to levels at which Escherichia coli and Streptococcus uberis do not survive. Most of the counts of E coli and faecal streptococci in the top layers of straw were above 10(6) colony-forming units/g. Counts of E coli and S uberis were much higher in the beds of early lactation cows than in those of dry cows. Many of the early lactation cows were heavily and persistently contaminated with faeces. Dry cows were much cleaner. Groups of cows with firmer faeces were also cleaner. The farm with the lowest incidence of mastitis had the cleanest cows and the most satisfactory beds.
Collapse
Affiliation(s)
- W R Ward
- Division of Farm Animal Studies, University of Liverpool, Veterinary Teaching Hospital, Leahurst, Neston
| | | | | | | | | | | |
Collapse
|
41
|
Abstract
Women who smoke and take oral contraceptives (OCs) have significantly increased risk of cardiovascular disease, but the exact mechanismsfor the increased risk are not known. Cardiovascular reactivity to psychological stress may be one mechanism for the enhanced risk, but the small number of studies examining whether OC users who smoke have greater reactivity have produced mixed results. The purpose of this study was to examine the effect of chronic cigarette smoking, acute nicotine administration, and OC use on cardiovascular and lipid reactivity. Sixty healthy women, half of whom had been using OCs for at least the previous 6 months, participated in the study. Approximately two thirds were smokers and were randomized to be tested after either a 12-hr nicotine deprivation or administration of nicotine gum. One third were nonsmokers. Heart rate, blood pressure, and lipid measures were taken at rest, during a videotaped speech task, and during recovery from the task. Results indicated that, among OC nonusers, there was no effect of smoking status or nicotine administration on cardiovascular reactivity. However, among OC users, nonsmokers had significantly greater heart rate and diastolic blood pressure reactivity to stress. These data show that acute nicotine administration, in the form of nicotine gum, has no effect on cardiovascular or lipid stress reactivity in women. However OC use among nonsmoking women is associated with greater cardiovascular reactivity to stress.
Collapse
Affiliation(s)
- S G West
- Pennsylvania State University, USA
| | | | | | | | | |
Collapse
|
42
|
Abstract
Arterialized and venous blood was compared to determine if the arterialization procedure enhances the detection of stress-related changes in catecholamines. Lipid and hematologic measures were also compared for possible distortion by arterialization. Fifteen men completed two stressors. Indwelling venous catheters were placed retrograde in each hand, and the right hand was warmed to a constant temperature. Blood samples were taken simultaneously from both hands, and plasma catecholamines were determined. Arterialization increased baseline epinephrine; there were no effects of arterialization on catecholamines during stress, nor in lipid or hematologic measures during baseline or stress. Thus, arterialization of blood results in small increases in resting epinephrine levels, but does not obscure lipid measures. More importantly, arterialization of venous blood does not enhance the detection of stress-related changes in catecholamines.
Collapse
Affiliation(s)
- C M Stoney
- Department of Psychology, Ohio State University, Columbus 43210-1222, USA.
| | | |
Collapse
|
43
|
Abstract
OBJECTIVE The purpose of this study was to examine the relationships between depressed mood and parasympathetic control of the heart in healthy men and women at rest and during two stressors. METHODS Fifty-three healthy college students completed a laboratory stress protocol that included a baseline resting period, a challenging speech task, and a forehead cold pressor task. Depressed mood was assessed using the Beck Depression Inventory (BDI). Parasympathetic cardiac control was measured as the high-frequency (0.12-0.40 Hz) component (HF) of heart rate variability using power spectrum analysis. Blood pressure, respiration rate, and respiration amplitude were measured simultaneously. RESULTS Participants were categorized as having a high or low depressed mood on the basis of median splits of their BDI scores. Those in the high depressed mood group had significantly greater reductions in HF during the speech task and significantly smaller increases in HF during the forehead cold pressor task than those in the low depressed mood group. Women had significantly greater reductions in HF during the speech task and smaller increases in HF during the forehead cold pressor task than men. However, gender and depressed mood did not interact to predict changes in HF. CONCLUSIONS Depressed mood is related to the magnitude of decrease in parasympathetic cardiac control during stressors in healthy men and women. These findings extend those of previous studies, in which a similar phenomenon was observed among patients with cardiac disease. Because the participants in this study were healthy, the relationship between depressed mood and parasympathetic cardiac control does not seem to be secondary to cardiovascular disease.
Collapse
Affiliation(s)
- J W Hughes
- Ohio State University, Columbus 43210-1222, USA
| | | |
Collapse
|
44
|
Abstract
In the current study, we examined lipid and cardiovascular responses to an acute stressor among men with and without a parental history of myocardial infarction. 37 men were selected from a large group who completed medical history questionnaires and interviews. Twenty-two men who denied parental history of heart disease (negative parental history) were compared with 15 men with one or both parents who had suffered a myocardial infarction (positive parental history). Total cholesterol, high- and low-density lipoprotein cholesterol, triglycerides, heart rate, and blood pressure were measured at rest and during a videotaped speech stressor. Positive parental history men had significantly higher low-density lipoprotein cholesterol levels and blood pressure at baseline, significantly lower high-density lipoprotein cholesterol levels at baseline, and significantly larger total cholesterol and low-density lipoprotein cholesterol reactivity, relative to negative parental history men. Because parental history is a risk factor for subsequent cardiovascular morbidity and mortality, these data suggest that lipid reactivity to stress may be biologically important.
Collapse
Affiliation(s)
- C M Stoney
- Department of Psychology, Ohio State University, Columbus 43210-1222, USA.
| | | |
Collapse
|
45
|
Rearwin DT, Tang JH, Hughes JW. Causes of blindness among Navajo Indians: an update. J Am Optom Assoc 1997; 68:511-7. [PMID: 9279051] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
BACKGROUND The causes of blindness among Navajo Indians, an ethnically distinct community within the United States, were last studied in 1982. This article presents an updated report on the causes of blindness among the Navajo. METHODS Staff optometrists at each of the hospitals and clinics on the Navajo Reservation collected information for each affected eye: date of onset, cause, blinding process, and best visual acuity. In terms of the total number of eyes affected, it was found that the most frequently encountered etiology was trauma, followed by congenital causes, diabetes mellitus, primary open-angle glaucoma, age-related macular degeneration, and trachoma. CONCLUSIONS Considering raw numbers as well as preventability, it is suggested that trauma, diabetes mellitus, and primary open-angle glaucoma be targeted for a focused intervention of patient-as well as public-education aimed at reducing blindness from these causes.
Collapse
Affiliation(s)
- D T Rearwin
- Southern California College of Optometry, Fullerton, USA
| | | | | |
Collapse
|
46
|
Faull WB, Hughes JW, Clarkson MJ, Downham DY, Manson FJ, Merritt JB, Murray RD, Russell WB, Sutherst JE, Ward WR. Epidemiology of lameness in dairy cattle: the influence of cubicles and indoor and outdoor walking surfaces. Vet Rec 1996; 139:130-6. [PMID: 8863400 DOI: 10.1136/vr.139.6.130] [Citation(s) in RCA: 70] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
A survey of cubicles and indoor and outdoor walking surfaces on 37 farms served by four veterinary practices in Somerset, Cheshire, Wirral and west. Wales was carried out in 1989 to 1991. A study of the space requirements of Friesian/Holstein cows at pasture showed that they required approximately 240 cm x 120 cm lying space and a further 60 cm lunging space for rising. By these standards, 87 per cent of the cubicles were too short and 50 per cent were too wide or too narrow. Over 1500 observations on cows lying down, rising and standing indicated that only 12 per cent of the cubicles permitted real freedom of movement; 91 per cent of top partition rails were judged to be too low and 70 per cent of bottom rails too low or too high. In addition, the kerb was very high in 76 per cent of the cubicles. As a result, 10 per cent of cows appeared moderately or severely restricted when lying down, 33 per cent when rising and 55 per cent when standing. Over 2000 cubicle beds were also studied; 75 per cent had a concrete base and of those, 63 per cent were judged to have too little bedding and 11 per cent next to none. Higher incidences and prevalences of lameness were associated with limited borrowing space (P < 0.01) low bottom rails (P < 0.05), high kerbs (P < 0.05) and inadequate bedding (P < 0.01). Of 3190 walking surfaces, only 25 per cent were classified as satisfactory in the first winter and 34 per cent in the second. In general, surfaces in silage bays were too rough and those in other sites were too smooth. The farms with the smoothest indoor walking surfaces had a significantly higher incidence of lameness (P < 0.01). Of 3335 outdoor walking surfaces only 25 per cent were classified as satisfactory, and 70 per cent were too rough. The incidence of lameness was not significantly related to these findings.
Collapse
Affiliation(s)
- W B Faull
- Department of Veterinary Clinical Science and Animal Husbandry, University of Liverpool, Leahurst, Neston, South Wirral
| | | | | | | | | | | | | | | | | | | |
Collapse
|
47
|
Murray RD, Downham DY, Clarkson MJ, Faull WB, Hughes JW, Manson FJ, Merritt JB, Russell WB, Sutherst JE, Ward WR. Epidemiology of lameness in dairy cattle: description and analysis of foot lesions. Vet Rec 1996; 138:586-91. [PMID: 8799985 DOI: 10.1136/vr.138.24.586] [Citation(s) in RCA: 174] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
Information from 37 dairy farms, in four regions of England and Wales provided data on 8991 lesions and the preventive trimming of 4837 cows' feet. Of the total of 13,828 forms returned, veterinary surgeons treated 32 per cent and farmers or stockmen 46 per cent. Of the 8645 lesions associated with episodes of lameness, lesions in the hindlimbs accounted for 92 per cent, of which 65 per cent were in the outer claw, 20 per cent in the skin and 14 per cent in the inner claw. Sole ulcers (40 per cent) and white line lesions (29 per cent) were the predominant diseases of horn, and digital dermatitis (40 per cent) was the most common disease of the skin. Subjective assessments showed that sandcrack, penetration of the sole by foreign bodies and interdigital necrobacillosis were associated with the most severe cases of lameness. There was a significant seasonal effect in the reporting of lesions.
Collapse
Affiliation(s)
- R D Murray
- Department of Veterinary Clinical Science and Animal Husbandry, University of Liverpool, Neston, South Wirral
| | | | | | | | | | | | | | | | | | | |
Collapse
|
48
|
Clarkson MJ, Downham DY, Faull WB, Hughes JW, Manson FJ, Merritt JB, Murray RD, Russell WB, Sutherst JE, Ward WR. Incidence and prevalence of lameness in dairy cattle. Vet Rec 1996; 138:563-7. [PMID: 8795183 DOI: 10.1136/vr.138.23.563] [Citation(s) in RCA: 196] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
A survey was made of 37 dairy farms in Wirral, mid-Cheshire, mid-Somerset and Dyfed, Wales, to assess the incidence and prevalence of lameness in the cows between May 1989 and September 1991. The incidence was obtained from records made whenever a cow was examined for lameness or received preventive foot-trimming. The mean annual incidence was 54.6 new cases per 100 cows with a range from 10.7 to 170.1 and the mean values during summer and winter were 22.9 and 31.7, respectively. The prevalence of lameness was measured by regular visits at which locomotion was scored on a scale of 1 to 5, and the prevalence of lameness was calculated for each visit as the proportion of cows with scores of 3 or more. The mean annual prevalence over the whole period was 20.6 per cent with a range from 2.0 to 53.9 per cent for the 37 farms. The mean prevalences during summer and winter were 18.6 and 25.0 per cent, respectively. The prevalence measured at a single visit in midsummer or midwinter was significantly correlated with the mean prevalence over the whole corresponding period and may be useful as an assessment of the extent of lameness in a herd and the efficacy of control measures. There was evidence that training farmers to recognise early cases of lameness and request veterinary treatment resulted in a marked reduction in the duration of cases of lameness.
Collapse
Affiliation(s)
- M J Clarkson
- Department of Veterinary Clinical Science and Animal Husbandry, University of Liverpool, Veterinary Teaching Hospital, Neston, South Wirral
| | | | | | | | | | | | | | | | | | | |
Collapse
|
49
|
Abstract
Lying down and other behavioural activities of dairy cows were studied for three 24-hour periods in a straw yard. The cows spent a total of 13.6 hours in the straw yard and lay down for 9.7 hours. The lying down time in one observation was 10.8 hours and this period may be considered ideal because there was little disturbance during that observation. Significantly more time was spent lying down at night than in the day and significantly more time was spent lying down and ruminating than standing up and ruminating. The total time spent lying down was significantly positively correlated with the time spent lying down and ruminating. Ten hours or more spent lying down may be adequate for proper rest in dairy cattle. Straw yards are better than many cubicles for lying and a longer period spent lying down may be important for the prevention of lameness in dairy cows.
Collapse
Affiliation(s)
- S S Singh
- Department of Veterinary Clinical Science and Animal Husbandry, University of Liverpool, Leahurst, Neston, South Wirral
| | | | | | | | | |
Collapse
|
50
|
Singh SS, Ward WR, Lautenbach K, Hughes JW, Murray RD. Behaviour of first lactation and adult dairy cows while housed and at pasture and its relationship with sole lesions. Vet Rec 1993; 133:469-74. [PMID: 8310615 DOI: 10.1136/vr.133.19.469] [Citation(s) in RCA: 62] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
The times spent lying down and standing by first lactation and adult cows while they were housed and while they were at pasture were studied and related during the period of housing to the incidence of sole lesions in first lactation cows. First lactation cows lay down for a shorter time in the early housing period than later. First lactation and adult cows lay down for longer when at pasture. Maximum lying time was significantly longer and the frequency of lying lower on pasture than indoors. The times spent lying and standing and the frequency of lying were related to the incidence of sole lesions. Rumination time was not related to the occurrence of sole lesions although there were significant variations in rumination behaviour while the animals were housed and at pasture. The patterns of lying and other activities of first lactation and adult cows while they were housed were quite different from those while they were at pasture.
Collapse
Affiliation(s)
- S S Singh
- Department of Veterinary Clinical Science and Animal Husbandry, University of Liverpool Veterinary Field Station, Leahurst, Neston, South Wirral
| | | | | | | | | |
Collapse
|