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Mallinson JB, Heywood ZE, Daniels RK, Arnold MD, Bones PJ, Brown SA. Reservoir computing using networks of memristors: effects of topology and heterogeneity. Nanoscale 2023. [PMID: 37211815 DOI: 10.1039/d2nr07275k] [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: 05/23/2023]
Abstract
Reservoir computing (RC) has attracted significant interest as a framework for the implementation of novel neuromorphic computing architectures. Previously attention has been focussed on software-based reservoirs, where it has been demonstrated that reservoir topology plays a role in task performance, and functional advantage has been attributed to small-world and scale-free connectivity. However in hardware systems, such as electronic memristor networks, the mechanisms responsible for the reservoir dynamics are very different and the role of reservoir topology is largely unknown. Here we compare the performance of a range of memristive reservoirs in several RC tasks that are chosen to highlight different system requirements. We focus on percolating networks of nanoparticles (PNNs) which are novel self-assembled nanoscale systems that exhibit scale-free and small-world properties. We find that the performance of regular arrays of uniform memristive elements is limited by their symmetry but that this symmetry can be broken either by a heterogeneous distribution of memristor properties or a scale-free topology. The best perfomance across all tasks is observed for a scale-free network with uniform memistor properties. These results provide insight into the role of topology in neuromorphic reservoirs as well as an overview of the computational performance of scale-free networks of memristors in a range of benchmark tasks.
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Affiliation(s)
- J B Mallinson
- The MacDiarmid Institute for Advanced Materials and Nanotechnology, School of Physical and Chemical Sciences, University of Canterbury, Christchurch, New Zealand.
| | - Z E Heywood
- The MacDiarmid Institute for Advanced Materials and Nanotechnology, School of Physical and Chemical Sciences, University of Canterbury, Christchurch, New Zealand.
- Electrical and Computer Engineering, University of Canterbury, Private Bag 4800, Christchurch 8140, New Zealand
| | - R K Daniels
- The MacDiarmid Institute for Advanced Materials and Nanotechnology, School of Physical and Chemical Sciences, University of Canterbury, Christchurch, New Zealand.
| | - M D Arnold
- School of Mathematical and Physical Sciences, University of Technology Sydney, PO Box 123, Broadway, NSW 2007, Australia
| | - P J Bones
- The MacDiarmid Institute for Advanced Materials and Nanotechnology, School of Physical and Chemical Sciences, University of Canterbury, Christchurch, New Zealand.
- Electrical and Computer Engineering, University of Canterbury, Private Bag 4800, Christchurch 8140, New Zealand
| | - S A Brown
- The MacDiarmid Institute for Advanced Materials and Nanotechnology, School of Physical and Chemical Sciences, University of Canterbury, Christchurch, New Zealand.
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Daniels RK, Mallinson JB, Heywood ZE, Bones PJ, Arnold MD, Brown SA. Reservoir computing with 3D nanowire networks. Neural Netw 2022; 154:122-130. [PMID: 35882080 DOI: 10.1016/j.neunet.2022.07.001] [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] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2022] [Revised: 04/27/2022] [Accepted: 07/06/2022] [Indexed: 10/17/2022]
Abstract
Networks of nanowires are currently being explored for a range of applications in brain-like (or neuromorphic) computing, and especially in reservoir computing (RC). Fabrication of real-world computing devices requires that the nanowires are deposited sequentially, leading to stacking of the wires on top of each other. However, most simulations of computational tasks using these systems treat the nanowires as 1D objects lying in a perfectly 2D plane - the effect of stacking on RC performance has not yet been established. Here we use detailed simulations to compare the performance of perfectly 2D and quasi-3D (stacked) networks of nanowires in two tasks: memory capacity and nonlinear transformation. We also show that our model of the junctions between nanowires is general enough to describe a wide range of memristive networks, and consider the impact of physically realistic electrode configurations on performance. We show that the various networks and configurations have a strikingly similar performance in RC tasks, which is surprising given their radically different topologies. Our results show that networks with an experimentally achievable number of electrodes perform close to the upper bounds achievable when using the information from every wire. However, we also show important differences, in particular that the quasi-3D networks are more resilient to changes in the input parameters, generalizing better to noisy training data. Since previous literature suggests that topology plays an important role in computing performance, these results may have important implications for future applications of nanowire networks in neuromorphic computing.
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Affiliation(s)
- R K Daniels
- The MacDiarmid Institute for Advanced Materials and Nanotechnology, School of Physical and Chemical Sciences, Te Kura Matū, University of Canterbury, Private Bag 4800, Christchurch 8140, New Zealand
| | - J B Mallinson
- The MacDiarmid Institute for Advanced Materials and Nanotechnology, School of Physical and Chemical Sciences, Te Kura Matū, University of Canterbury, Private Bag 4800, Christchurch 8140, New Zealand
| | - Z E Heywood
- Electrical and Computer Engineering, University of Canterbury, Private Bag 4800, Christchurch 8140, New Zealand
| | - P J Bones
- Electrical and Computer Engineering, University of Canterbury, Private Bag 4800, Christchurch 8140, New Zealand
| | - M D Arnold
- School of Mathematical and Physical Sciences, University of Technology Sydney, PO Box 123 Broadway NSW 2007, Australia
| | - S A Brown
- The MacDiarmid Institute for Advanced Materials and Nanotechnology, School of Physical and Chemical Sciences, Te Kura Matū, University of Canterbury, Private Bag 4800, Christchurch 8140, New Zealand.
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Foss L, Brown SA, Sutherland S, Miller CJ, Philliber S. A randomized controlled trial of the impact of the Teen Council peer education program on youth development. Health Educ Res 2022; 37:36-47. [PMID: 35134906 DOI: 10.1093/her/cyac001] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/30/2021] [Revised: 01/07/2022] [Accepted: 01/24/2022] [Indexed: 06/14/2023]
Abstract
This paper presents results of an impact evaluation of Teen Council, a program that trains youth as peer educators. Teen Council is designed to help peer educators make healthy sexual and reproductive decisions, increase their confidence and abilities to educate their peers and inspire them to advocate for just sexual policies. The program's impact on these educators was evaluated using a randomized controlled trial. Over 5 years, interested high school students in seven states were randomly assigned to a study condition. An intent-to-treat framework using ordinary least square (OLS) regression was employed to measure program effects. Relative to control, Teen Council youth showed enhanced comfort with their own sexuality, greater comfort with and more frequent communication with parents about sexuality and more positive sexual health behaviors, including accessing reproductive health care and adopting more effective means of contraception. Teen Council youth also reported greater confidence in talking with peers about sexuality and more confidence in their civic engagement skills.
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Affiliation(s)
- L Foss
- Philliber Research & Evaluation, 16 Main Street, Accord, NY 12404, USA
| | - S A Brown
- Philliber Research & Evaluation, 16 Main Street, Accord, NY 12404, USA
| | - S Sutherland
- Planned Parenthood of the Great Northwest and the Hawaiian Islands, 2001 E. Madison, Seattle, WA 98122, USA
| | - C J Miller
- Planned Parenthood of the Great Northwest and the Hawaiian Islands, 2001 E. Madison, Seattle, WA 98122, USA
| | - S Philliber
- Philliber Research & Evaluation, 16 Main Street, Accord, NY 12404, USA
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Zheng L, Foley KR, Grove R, Elley K, Brown SA, Leong DJ, Li X, Pellicano E, Trollor JN, Hwang YIJ. The use of everyday and assistive technology in the lives of older autistic adults. Autism 2021; 26:1550-1562. [PMID: 34841926 DOI: 10.1177/13623613211058519] [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] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
LAY ABSTRACT Technology has the potential to help people with various support needs live more autonomous lives. This includes autistic individuals. In this article, we look at how older autistic adults use technology in their daily lives. Past research examining technology use and autism has mainly focused on helping children to learn new skills. To date, very little research has been conducted looking at how to create and design technology for use by older autistic adults. This is concerning because older autistic adults will likely have supports needs that match or exceed those of similarly aged non-autistic individuals. In this article, we spoke to autistic adults over 50 years about their daily experiences and how they use technology. We identified some important ways that older autistic adults use technology in their daily lives, as well as a number of support needs and barriers to technology use. Based on the findings, we were able to provide some guidelines and recommendations for technology developers and service providers to assist with designing, creating and using technology with older autistic adults.
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Affiliation(s)
- Lidan Zheng
- UNSW Sydney, Australia.,Neuroscience Research Australia, Australia
| | | | | | | | | | | | - Xue Li
- UNSW Centre for Primary Health Care and Equity, Australia
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Infante MA, Eberson SC, Zhang Y, Brumback T, Brown SA, Colrain IM, Baker FC, Clark DB, De Bellis MD, Goldston D, Nagel BJ, Nooner KB, Zhao Q, Pohl KM, Sullivan EV, Pfefferbaum A, Tapert SF, Thompson WK. Adolescent Binge Drinking Is Associated With Accelerated Decline of Gray Matter Volume. Cereb Cortex 2021; 32:2611-2620. [PMID: 34729592 DOI: 10.1093/cercor/bhab368] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/13/2021] [Revised: 08/27/2021] [Accepted: 08/28/2021] [Indexed: 11/12/2022] Open
Abstract
The age- and time-dependent effects of binge drinking on adolescent brain development have not been well characterized even though binge drinking is a health crisis among adolescents. The impact of binge drinking on gray matter volume (GMV) development was examined using 5 waves of longitudinal data from the National Consortium on Alcohol and NeuroDevelopment in Adolescence study. Binge drinkers (n = 166) were compared with non-binge drinkers (n = 82 after matching on potential confounders). Number of binge drinking episodes in the past year was linked to decreased GMVs in bilateral Desikan-Killiany cortical parcellations (26 of 34 with P < 0.05/34) with the strongest effects observed in frontal regions. Interactions of binge drinking episodes and baseline age demonstrated stronger effects in younger participants. Statistical models sensitive to number of binge episodes and their temporal proximity to brain volumes provided the best fits. Consistent with prior research, results of this study highlight the negative effects of binge drinking on the developing brain. Our results present novel findings that cortical GMV decreases were greater in closer proximity to binge drinking episodes in a dose-response manner. This relation suggests a causal effect and raises the possibility that normal growth trajectories may be reinstated with alcohol abstinence.
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Affiliation(s)
- M A Infante
- Department of Psychiatry, University of California, San Diego, La Jolla, CA, USA
| | - S C Eberson
- Department of Psychiatry, University of California, San Diego, La Jolla, CA, USA
| | - Y Zhang
- Division of Biostatistics, Herbert Wertheim School of Public Health and Human Longevity Science, University of California, San Diego, USA.,Population Neuroscience and Genetics Lab, University of California, San Diego, USA
| | - T Brumback
- Department of Psychological Science, Northern Kentucky University, Kentucky, USA
| | - S A Brown
- Department of Psychiatry, University of California, San Diego, La Jolla, CA, USA.,Department of Psychology, University of California, San Diego, La Jolla, CA, USA
| | - I M Colrain
- Center for Health Sciences, SRI International, Menlo Park, CA, USA
| | - F C Baker
- Center for Health Sciences, SRI International, Menlo Park, CA, USA
| | - D B Clark
- Department of Psychiatry, University of Pittsburgh, Pittsburgh, PA, USA
| | - M D De Bellis
- Department of Psychiatry & Behavioral Sciences, Duke University, Durham, NC, USA
| | - D Goldston
- Department of Psychiatry & Behavioral Sciences, Duke University, Durham, NC, USA
| | - B J Nagel
- Departments of Psychiatry and Behavioral Neuroscience, Oregon Health & Sciences University, Portland, OR, USA
| | - K B Nooner
- Department of Psychology, University of North Carolina Wilmington, Wilmington, NC, USA
| | - Q Zhao
- Department of Psychiatry and Behavioral Sciences, Stanford University, Stanford, CA, USA
| | - K M Pohl
- Center for Health Sciences, SRI International, Menlo Park, CA, USA.,Department of Psychiatry and Behavioral Sciences, Stanford University, Stanford, CA, USA
| | - E V Sullivan
- Department of Psychiatry and Behavioral Sciences, Stanford University, Stanford, CA, USA
| | - A Pfefferbaum
- Center for Health Sciences, SRI International, Menlo Park, CA, USA.,Department of Psychiatry and Behavioral Sciences, Stanford University, Stanford, CA, USA
| | - S F Tapert
- Department of Psychiatry, University of California, San Diego, La Jolla, CA, USA
| | - W K Thompson
- Division of Biostatistics, Herbert Wertheim School of Public Health and Human Longevity Science, University of California, San Diego, USA.,Population Neuroscience and Genetics Lab, University of California, San Diego, USA.,Department of Radiology, University of California, San Diego, USA
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6
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Lisdahl KM, Tapert S, Sher KJ, Gonzalez R, Nixon SJ, Ewing SWF, Conway KP, Wallace A, Sullivan R, Hatcher K, Kaiver C, Thompson W, Reuter C, Bartsch H, Wade NE, Jacobus J, Albaugh MD, Allgaier N, Anokhin AP, Bagot K, Baker FC, Banich MT, Barch DM, Baskin-Sommers A, Breslin FJ, Brown SA, Calhoun V, Casey BJ, Chaarani B, Chang L, Clark DB, Cloak C, Constable RT, Cottler LB, Dagher RK, Dapretto M, Dick A, Do EK, Dosenbach NUF, Dowling GJ, Fair DA, Florsheim P, Foxe JJ, Freedman EG, Friedman NP, Garavan HP, Gee DG, Glantz MD, Glaser P, Gonzalez MR, Gray KM, Grant S, Haist F, Hawes S, Heeringa SG, Hermosillo R, Herting MM, Hettema JM, Hewitt JK, Heyser C, Hoffman EA, Howlett KD, Huber RS, Huestis MA, Hyde LW, Iacono WG, Isaiah A, Ivanova MY, James RS, Jernigan TL, Karcher NR, Kuperman JM, Laird AR, Larson CL, LeBlanc KH, Lopez MF, Luciana M, Luna B, Maes HH, Marshall AT, Mason MJ, McGlade E, Morris AS, Mulford C, Nagel BJ, Neigh G, Palmer CE, Paulus MP, Pecheva D, Prouty D, Potter A, Puttler LI, Rajapakse N, Ross JM, Sanchez M, Schirda C, Schulenberg J, Sheth C, Shilling PD, Sowell ER, Speer N, Squeglia L, Sripada C, Steinberg J, Sutherland MT, Tomko R, Uban K, Vrieze S, Weiss SRB, Wing D, Yurgelun-Todd DA, Zucker RA, Heitzeg MM. Substance use patterns in 9-10 year olds: Baseline findings from the adolescent brain cognitive development (ABCD) study. Drug Alcohol Depend 2021; 227:108946. [PMID: 34392051 PMCID: PMC8833837 DOI: 10.1016/j.drugalcdep.2021.108946] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/15/2021] [Revised: 06/03/2021] [Accepted: 06/05/2021] [Indexed: 01/28/2023]
Abstract
BACKGROUND The Adolescent Brain Cognitive Development ™ Study (ABCD Study®) is an open-science, multi-site, prospective, longitudinal study following over 11,800 9- and 10-year-old youth into early adulthood. The ABCD Study aims to prospectively examine the impact of substance use (SU) on neurocognitive and health outcomes. Although SU initiation typically occurs during teen years, relatively little is known about patterns of SU in children younger than 12. METHODS This study aims to report the detailed ABCD Study® SU patterns at baseline (n = 11,875) in order to inform the greater scientific community about cohort's early SU. Along with a detailed description of SU, we ran mixed effects regression models to examine the association between early caffeine and alcohol sipping with demographic factors, externalizing symptoms and parental history of alcohol and substance use disorders (AUD/SUD). PRIMARY RESULTS At baseline, the majority of youth had used caffeine (67.6 %) and 22.5 % reported sipping alcohol (22.5 %). There was little to no reported use of other drug categories (0.2 % full alcohol drink, 0.7 % used nicotine, <0.1 % used any other drug of abuse). Analyses revealed that total caffeine use and early alcohol sipping were associated with demographic variables (p's<.05), externalizing symptoms (caffeine p = 0002; sipping p = .0003), and parental history of AUD (sipping p = .03). CONCLUSIONS ABCD Study participants aged 9-10 years old reported caffeine use and alcohol sipping experimentation, but very rare other SU. Variables linked with early childhood alcohol sipping and caffeine use should be examined as contributing factors in future longitudinal analyses examining escalating trajectories of SU in the ABCD Study cohort.
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Affiliation(s)
- Krista M Lisdahl
- University of Wisconsin, Milwaukee, WI, United States; Medical College of Wisconsin, Milwaukee, WI, United States.
| | - Susan Tapert
- University of California, San Diego, CA, United States
| | | | - Raul Gonzalez
- Florida International University, Miami, FL, United States
| | - Sara Jo Nixon
- University of Florida, Gainesville, FL, United States
| | | | - Kevin P Conway
- National Institute on Drug Abuse, NIH, Bethesda, MD, United States
| | - Alex Wallace
- University of Wisconsin, Milwaukee, WI, United States
| | - Ryan Sullivan
- University of Wisconsin, Milwaukee, WI, United States
| | - Kelah Hatcher
- University of Wisconsin, Milwaukee, WI, United States
| | | | - Wes Thompson
- University of California, San Diego, CA, United States
| | - Chase Reuter
- University of California, San Diego, CA, United States
| | - Hauke Bartsch
- University of California, San Diego, CA, United States
| | | | | | - M D Albaugh
- University of Vermont, Burlington, VT, United States
| | - N Allgaier
- University of Vermont, Burlington, VT, United States
| | - A P Anokhin
- Washington University, St. Louis, MO, United States
| | - K Bagot
- University of California, San Diego, CA, United States; Icahn School of Medicine at Mount Sinai, United States
| | - F C Baker
- SRI International, Menlo Park, CA, United States
| | - M T Banich
- University of Colorado Boulder, CO, United States
| | - D M Barch
- Washington University, St. Louis, MO, United States
| | | | - F J Breslin
- Laureate Institute for Brain Research, Tulsa, OK, United States
| | - S A Brown
- University of California, San Diego, CA, United States
| | - V Calhoun
- Georgia State University, Atlanta, GA, United States
| | - B J Casey
- Yale University, New Haven, CT, United States
| | - B Chaarani
- University of Vermont, Burlington, VT, United States
| | - L Chang
- University of Maryland School of Medicine, Baltimore, MD, United States
| | - D B Clark
- University of Pittsburgh, Pittsburgh, PA, United States
| | - C Cloak
- University of Maryland School of Medicine, Baltimore, MD, United States
| | | | - L B Cottler
- University of Florida, Gainesville, FL, United States
| | - R K Dagher
- National Institute of Minority Health and Health Disparities, Bethesda, MD, United States
| | - M Dapretto
- University of California, Los Angeles, CA, United States
| | - A Dick
- Florida International University, Miami, FL, United States
| | - E K Do
- Virginia Commonwealth University, Richmond, VA, United States
| | | | - G J Dowling
- National Institute on Drug Abuse, NIH, Bethesda, MD, United States
| | - D A Fair
- University of Minnesota, Minneapolis, MN, United States
| | - P Florsheim
- University of Wisconsin, Milwaukee, WI, United States
| | - J J Foxe
- University of Rochester, Rochester, NY, United States
| | - E G Freedman
- University of Rochester, Rochester, NY, United States
| | - N P Friedman
- University of Colorado Boulder, CO, United States
| | - H P Garavan
- University of Vermont, Burlington, VT, United States
| | - D G Gee
- Yale University, New Haven, CT, United States
| | - M D Glantz
- National Institute on Drug Abuse, NIH, Bethesda, MD, United States
| | - P Glaser
- Washington University, St. Louis, MO, United States
| | - M R Gonzalez
- Children’s Hospital Los Angeles, Los Angeles, CA, United States
| | - K M Gray
- Medical University of South Carolina, Charleston, SC, United States
| | - S Grant
- National Institute on Drug Abuse, NIH, Bethesda, MD, United States
| | - F Haist
- University of California, San Diego, CA, United States
| | - S Hawes
- Florida International University, Miami, FL, United States
| | - S G Heeringa
- University of Michigan, Ann Arbor, MI, United States
| | - R Hermosillo
- Oregon Health & Science University, Portland, OR, United States
| | - M M Herting
- University of Southern California, Los Angeles, CA, United States
| | - J M Hettema
- Virginia Commonwealth University, Richmond, VA, United States
| | - J K Hewitt
- University of Colorado Boulder, CO, United States
| | - C Heyser
- University of California, San Diego, CA, United States
| | - E A Hoffman
- National Institute on Drug Abuse, NIH, Bethesda, MD, United States
| | - K D Howlett
- National Institute on Drug Abuse, NIH, Bethesda, MD, United States
| | - R S Huber
- University of Utah, Salt Lake City, UT, United States
| | - M A Huestis
- University of California, San Diego, CA, United States; Thomas Jefferson University, Philadelphia, PA, United States
| | - L W Hyde
- University of Michigan, Ann Arbor, MI, United States
| | - W G Iacono
- University of Minnesota, Minneapolis, MN, United States
| | - A Isaiah
- University of Maryland School of Medicine, Baltimore, MD, United States
| | - M Y Ivanova
- University of Vermont, Burlington, VT, United States
| | - R S James
- American Psychistric Association, United States
| | - T L Jernigan
- University of California, San Diego, CA, United States
| | - N R Karcher
- Washington University, St. Louis, MO, United States
| | - J M Kuperman
- University of California, San Diego, CA, United States
| | - A R Laird
- Florida International University, Miami, FL, United States
| | - C L Larson
- University of Wisconsin, Milwaukee, WI, United States
| | - K H LeBlanc
- National Institute on Drug Abuse, NIH, Bethesda, MD, United States
| | - M F Lopez
- National Institute on Drug Abuse, NIH, Bethesda, MD, United States
| | - M Luciana
- University of Minnesota, Minneapolis, MN, United States
| | - B Luna
- University of Pittsburgh, Pittsburgh, PA, United States
| | - H H Maes
- Virginia Commonwealth University, Richmond, VA, United States
| | - A T Marshall
- Children’s Hospital Los Angeles, Los Angeles, CA, United States
| | - M J Mason
- University of Tennessee, Knoxville, TN, United States
| | - E McGlade
- University of Utah, Salt Lake City, UT, United States
| | - A S Morris
- Laureate Institute for Brain Research, Tulsa, OK, United States; Oklahoma State University, Stillwater, OK, United States
| | - C Mulford
- National Institute on Drug Abuse, NIH, Bethesda, MD, United States
| | - B J Nagel
- Oregon Health & Science University, Portland, OR, United States
| | - G Neigh
- Virginia Commonwealth University, Richmond, VA, United States
| | - C E Palmer
- University of California, San Diego, CA, United States
| | - M P Paulus
- Laureate Institute for Brain Research, Tulsa, OK, United States
| | - D Pecheva
- University of California, San Diego, CA, United States
| | - D Prouty
- SRI International, Menlo Park, CA, United States
| | - A Potter
- University of Vermont, Burlington, VT, United States
| | - L I Puttler
- University of Michigan, Ann Arbor, MI, United States
| | - N Rajapakse
- National Institute of Minority Health and Health Disparities, Bethesda, MD, United States
| | - J M Ross
- University of Colorado Anschutz Medical Campus, Aurora, CO, United States
| | - M Sanchez
- Florida International University, Miami, FL, United States
| | - C Schirda
- University of Pittsburgh, Pittsburgh, PA, United States
| | - J Schulenberg
- University of Michigan, Ann Arbor, MI, United States
| | - C Sheth
- University of Utah, Salt Lake City, UT, United States
| | - P D Shilling
- University of California, San Diego, CA, United States
| | - E R Sowell
- Children’s Hospital Los Angeles, Los Angeles, CA, United States
| | - N Speer
- University of Colorado Boulder, CO, United States
| | - L Squeglia
- Medical University of South Carolina, Charleston, SC, United States
| | - C Sripada
- University of Michigan, Ann Arbor, MI, United States
| | - J Steinberg
- Virginia Commonwealth University, Richmond, VA, United States
| | - M T Sutherland
- Florida International University, Miami, FL, United States
| | - R Tomko
- Medical University of South Carolina, Charleston, SC, United States
| | - K Uban
- University of California, Irvine, CA, United States
| | - S Vrieze
- University of Minnesota, Minneapolis, MN, United States
| | - S R B Weiss
- National Institute on Drug Abuse, NIH, Bethesda, MD, United States
| | - D Wing
- University of California, San Diego, CA, United States
| | | | - R A Zucker
- University of Michigan, Ann Arbor, MI, United States
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Brown SA, Burke TM. 0215 Sleep Duration Associated with Degraded Performance in Marksmanship and Weapon Stability During a 72-Hour Mission Training Exercise. Sleep 2020. [DOI: 10.1093/sleep/zsaa056.213] [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] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Abstract
Introduction
Military operations require vigilance and performance under stressful conditions while functioning with little to no sleep. Previous links between marksmanship performance and sleep restrictions have been shown primarily in novice Soldier populations, with significant decrements in reaction time and decision making skills rather than lethality, mobility, or weapon handling metrics. Additionally, previous research has focused on isolated static marksmanship tasks in laboratory settings. The research presented here assessed the relationship between changes in Soldier sleep duration as measured by actigraphy, and marksmanship performance when conducting a 72-hour military field training exercise.
Methods
Forty-six volunteers [42 males (age 24.5±4.2y; mean±SD)] across three platoons participated in this assessment of Soldier performance during a company-wide mission exercise. Sleep characteristics were collected via actigraphy throughout the mission. Marksmanship performance was assessed during pre-, mid-, and post-mission, utilizing an operationally relevant course that integrated a static self-paced shooting task with a dynamic, fast-paced multiple target task. Marksmanship was assessed in areas of lethality (e.g. accuracy, shot dispersion), mobility (e.g. acquisition, engagement times), and weapon handling stability (e.g. movement of barrel during aiming).
Results
Analysis utilized a multivariate analysis of covariance (MANCOVA) with platoon as the independent variable and total sleep time over the previous 24-hours as the covariant, during the mid-session assessment. The results indicated that prior sleep does significantly modulate marksmanship performance in areas of lethality and stability (ps<.05), but not mobility. Although all individuals received fewer hours of sleep than typical during the mission, those who received less sleep had greater inaccuracy and dispersion in their shot groups, and more barrel movement during weapon handling.
Conclusion
Marksmanship is a key military skill required of all Soldiers. This study has linked degradations in marksmanship lethality and stability performance in the field to naturally occurring sleep restrictions due to platoon-group variances during mission activities. Additionally, it is the first study to link weapon handling stability degradations to sleep loss. Further analysis will explore performance degradations associated with aspects of sleep quality, as well as individual platoon differences, such as leadership, qualifications, and resiliency.
Support
CCDC Soldier Center and Military Operational Medicine Research Program.
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Affiliation(s)
- S A Brown
- Combat Capabilities Development Command Soldier Center, Natick, MA
| | - T M Burke
- Behavioral Biology Branch, Center for Military Psychiatry and Neuroscience, Walter Reed Army Institute of Research (WRAIR), Silver Spring, MD
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Le Ster M, Chan JR, Ruck BJ, Brown SA, Natali F. Removable capping layer for air-sensitive GdN. Nanotechnology 2020; 31:275709. [PMID: 32208377 DOI: 10.1088/1361-6528/ab82d3] [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: 06/10/2023]
Abstract
The strongly correlated rare earth nitrides display unusual coupled magnetic, electronic and superconducting properties, with predicted topological states. However, their air-sensitiveness has prevented in-depth investigations of their properties. In this paper, we show that a 100 nm thick epitaxial samarium layer provides adequate passivation of 100 nm thick thin films of gadolinium nitride (GdN), the prototypical rare earth nitride, enabling ex-situ magnetic and structural characterizations. Using reflection high-energy electron diffraction, atomic force microscopy and energy dispersive x-ray spectroscopy, we investigate the thermal desorption of the samarium layer under vacuum. We finally demonstrate successful removal of the samarium capping layer in a separate vacuum chamber after exposure to air using a combination of argon ion sputtering and thermal desorption at 400 °C, recovering the GdN surface.
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Affiliation(s)
- M Le Ster
- The MacDiarmid Institute for Advanced Materials and Nanotechnology School of Physical and Chemical Sciences University of Canterbury Private Bag 4800 Christchurch 8140 New Zealand
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9
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Brown SA, Basu A, Kovatchev BP. Beyond HbA 1c : using continuous glucose monitoring metrics to enhance interpretation of treatment effect and improve clinical decision-making. Diabet Med 2019; 36:679-687. [PMID: 30848545 DOI: 10.1111/dme.13944] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [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] [Accepted: 03/05/2019] [Indexed: 12/27/2022]
Abstract
Assessment of glycaemic outcomes in the management of Type 1 and Type 2 diabetes has been revolutionized in the past decade with the increasing availability of accurate, user-friendly continuous glucose monitoring (CGM). This advancement has brought a need for new techniques to appropriately analyse and understand the voluminous and complex CGM data for application in research-related goals and clinical guidance for individuals. Traditionally, HbA1c was established using the Diabetes Control and Complications Trial (DCCT) and other trials as the ultimate measure of glycaemic control in terms of efficacy and, by default, risk of microvascular complications of diabetes. However, it is acknowledged that HbA1c alone is inadequate at describing an individual's daily glycaemic variation and risks for hypo- and hyperglycaemia, and it does not provide the guidance needed to decrease those risks. CGM data provide means by which to characterize an individual's daily glycaemic excursions on a different time scale measured in minutes rather than months. As a consequence, clinical reports, such as the ambulatory glucose profile, increasingly include summary statistics related to averages (mean glucose, time in range) as well as markers related to glycaemic variability (coefficient of variation, standard deviation). However, there is a need to translate those metrics into specific risks that can be addressed in an actionable plan by individuals with diabetes and providers. This review presents several clinical scenarios of glycaemic outcomes from CGM data that can be analysed to describe glycaemic variability and its attendant risks of hyperglycaemia and hypoglycaemia, moving towards relevant interpretation of the complex CGM data streams.
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Affiliation(s)
- S A Brown
- University of Virginia Center for Diabetes Technology, Charlottesville, VA, USA
- University of Virginia Division of Endocrinology and Metabolism, Charlottesville, VA, USA
| | - A Basu
- University of Virginia Center for Diabetes Technology, Charlottesville, VA, USA
- University of Virginia Division of Endocrinology and Metabolism, Charlottesville, VA, USA
| | - B P Kovatchev
- University of Virginia Division of Endocrinology and Metabolism, Charlottesville, VA, USA
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Abstract
We report a detailed study of neuromorphic switching behaviour in inherently complex percolating networks of self-assembled metal nanoparticles. We show that variation of the strength and duration of the electric field applied to this network of synapse-like atomic switches allows us to control the switching dynamics. Switching is observed for voltages above a well-defined threshold, with higher voltages leading to increased switching rates. We demonstrate two behavioral archetypes and show how the switching dynamics change as a function of duration and amplitude of the voltage stimulus. We show that the state of each synapse can influence the activity of the other synapses, leading to complex switching dynamics. We further demonstrate the influence of the morphology of the network on the measured device properties, and the constraints imposed by the overall network conductance. The correlated switching dynamics, device stability over long periods, and the simplicity of the device fabrication provide an attractive pathway to practical implementation of on-chip neuromorphic computing.
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Affiliation(s)
- S K Bose
- The MacDiarmid Institute for Advanced Materials and Nanotechnology, School of Physical and Chemical Sciences, University of Canterbury, Private Bag 4800, Christchurch 8140, New Zealand.
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Afonso T, Giguère S, Brown SA, Barton MH, Rapoport G, Barba M, Dembek KA, Toribio RE, Coleman AE. Preliminary investigation of orally administered benazepril in horses with left-sided valvular regurgitation. Equine Vet J 2017; 50:446-451. [PMID: 29044678 DOI: 10.1111/evj.12773] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2017] [Accepted: 10/11/2017] [Indexed: 11/26/2022]
Abstract
BACKGROUND Despite the paucity of data available, orally administered angiotensin-converting enzyme (ACE) inhibitors are empirically used in horses with valvular regurgitation. OBJECTIVE Evaluate the echocardiographic and hormonal changes in response to oral benazepril in horses with left-sided valvular regurgitation. STUDY DESIGN Prospective, randomised double-blind, placebo-controlled trial. METHODS Horses with mitral valve (MR) and/or aortic valve regurgitation (AR) received oral benazepril (n = 6) at a dosage of 1 mg/kg q 12 h or a placebo (n = 5) for 28 days. Echocardiography was performed before drug administration and after 28 days of treatment. Plasma renin activity, serum ACE activity, angiotensin II concentration, aldosterone concentration and biochemical variables were measured before drug administration and after 7 and 28 days of treatment. RESULTS Relative to baseline, horses treated with benazepril had statistically significant reduction in left ventricular internal diameter in systole (mean difference between groups = -0.97 cm; 95% CI = -1.5 to -0.43 cm), aortic sinus diameter (-0.31 cm; -0.54 to -0.07 cm), and percentage of the aortic annulus diameter occupied by the base of the AR jet (-17.05%; -31.17 to -2.93%) compared with horses receiving a placebo. In addition, horses treated with benazepril had a significantly greater increase in cardiac output (11.95 L/min; 1.17-22.73 L/min) and fractional shortening (7.59%; 3.3-11.88%) compared with horses receiving a placebo. Despite profound serum ACE inhibition, renin activity and concentrations of angiotensin II and aldosterone were not significantly different between treatment groups or among time points. MAIN LIMITATIONS Very small sample size and short treatment period. CONCLUSIONS Treatment with oral benazepril resulted in statistically significant echocardiographic changes that might indicate reduced cardiac afterload in horses with left-sided valvular regurgitation. Additional studies with a larger sample size will be necessary to determine if administration of benazepril is beneficial in horses with valvular regurgitation. The Summary is available in Spanish - see Supporting Information.
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Affiliation(s)
- T Afonso
- Department of Large Animal Medicine, College of Veterinary Medicine, University of Georgia, Athens, Georgia, USA
| | - S Giguère
- Department of Large Animal Medicine, College of Veterinary Medicine, University of Georgia, Athens, Georgia, USA
| | - S A Brown
- Department of Small Animal Medicine and Surgery, College of Veterinary Medicine, University of Georgia, Athens, Georgia, USA
| | - M H Barton
- Department of Large Animal Medicine, College of Veterinary Medicine, University of Georgia, Athens, Georgia, USA
| | - G Rapoport
- Department of Small Animal Medicine and Surgery, College of Veterinary Medicine, University of Georgia, Athens, Georgia, USA
| | - M Barba
- Department of Clinical Sciences, College of Veterinary Medicine, Auburn University, Auburn, Alabama, USA
| | - K A Dembek
- Department of Veterinary Clinical Sciences, College of Veterinary Medicine, The Ohio State University, Columbus, Ohio, USA
| | - R E Toribio
- Department of Veterinary Clinical Sciences, College of Veterinary Medicine, The Ohio State University, Columbus, Ohio, USA
| | - A E Coleman
- Department of Small Animal Medicine and Surgery, College of Veterinary Medicine, University of Georgia, Athens, Georgia, USA
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Wang X, Bian G, Xu C, Wang P, Hu H, Zhou W, Brown SA, Chiang TC. Topological phases in double layers of bismuthene and antimonene. Nanotechnology 2017; 28:395706. [PMID: 28745615 DOI: 10.1088/1361-6528/aa825f] [Citation(s) in RCA: 2] [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] [Indexed: 06/07/2023]
Abstract
Two-dimensional topological insulators show great promise for spintronic applications. Much attention has been placed on single atomic or molecular layers, such as bismuthene. The selections of such materials are, however, limited. To broaden the base of candidate materials with desirable properties for applications, we report herein an exploration of the physics of double layers of bismuthene and antimonene. The electronic structure of a film depends on the number of layers, and it can be modified by epitaxial strain, by changing the effective spin-orbit coupling strength, and by the manner in which the layers are geometrically stacked. First-principles calculations for the double layers reveal a number of phases, including topological insulators, topological semimetals, Dirac semimetals, trivial semimetals, and trivial insulators. Their phase boundaries and the stability of the phases are investigated. The results illustrate a rich pattern of phases that can be realized by tuning lattice strain and effective spin-orbit coupling.
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Affiliation(s)
- Xiaoxiong Wang
- Department of Applied Physics, Nanjing University of Science and Technology, Nanjing 210094, People's Republic of China. Department of Physics, University of Illinois at Urbana-Champaign, 1110 West Green Street, Urbana, Illinois 61801-3080, United States of America. Frederick Seitz Materials Research Laboratory, University of Illinois at Urbana-Champaign, 104 South Goodwin Avenue, Urbana, Illinois 61801-2902, United States of America
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Mason JA, Robertson JD, McCosker J, Williams BA, Brown SA. Assessment and validation of a defined fluid restriction protocol in the use of subcutaneous desmopressin for children with inherited bleeding disorders. Haemophilia 2016; 22:700-5. [PMID: 27385253 DOI: 10.1111/hae.12949] [Citation(s) in RCA: 6] [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] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 02/28/2016] [Indexed: 11/28/2022]
Abstract
INTRODUCTION Despite the availability of subcutaneous desmopressin (1-deamino-8-d-arginine vasopressin, SC-DDAVP) as a haemostatic agent for children with mild bleeding disorders, few publications specifically address the safety or efficacy of this mode of administration. AIM Our aim was to assess whether a defined fluid restriction protocol was effective in preventing hyponatremia in children receiving perioperative SC-DDAVP, and to document adequate biological and clinical response in this setting. METHODS We retrospectively analysed a cohort of children with mild bleeding disorders prescribed SC-DDAVP over a 5-year period following institution of a 'two-thirds maintenance' fluid restriction protocol. RESULTS Sixty-nine patients received SC-DDAVP following this protocol, including 15 with mild haemophilia A, 49 with von Willebrand disease (VWD) and five with platelet storage pool disorder. In patients who underwent formal preoperative assessment a complete or partial response was observed in 28/29 with type 1 VWD and 14/15 with mild haemophilia A. Perioperative SC-DDAVP provided excellent haemostasis in all patients, with no requirement for factor concentrate or blood products. Mild asymptomatic hyponatremia was detected in seven children who received multiple doses of DDAVP (lowest sodium 129 mmol L(-1) ); however, adherence to the prescribed fluid restriction protocol was questionable in six of these cases. Symptomatic hyponatremia was not observed. CONCLUSION Subcutaneous desmopressin was well-tolerated, with no serious side-effects observed, and good biological responses in preoperative trials. A two-thirds maintenance fluid regimen was effective at preventing symptomatic hyponatremia in our cohort, and is now the standard protocol for fluid restriction post-DDAVP administration in our centre.
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Affiliation(s)
- J A Mason
- Department of Haematology, Lady Cilento Children's Hospital, Brisbane, QLD, Australia.
| | - J D Robertson
- Department of Haematology, Lady Cilento Children's Hospital, Brisbane, QLD, Australia
| | - J McCosker
- Department of Haematology, Lady Cilento Children's Hospital, Brisbane, QLD, Australia
| | - B A Williams
- Department of Haematology, Lady Cilento Children's Hospital, Brisbane, QLD, Australia
| | - S A Brown
- Department of Haematology, Lady Cilento Children's Hospital, Brisbane, QLD, Australia
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Brown SA, Duchin SP, Villagomez ET. Diabetes Education in a Mexican-American Population: Pilot Testing of a Research-Based Videotape. Diabetes Educ 2016; 18:47-51. [PMID: 1370266 DOI: 10.1177/014572179201800108] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
A diabetes education videotape was designed and pilot tested in a sample of 30 Spanish-speaking Hispanic diabetic adults in a rural Texas-Mexico border community. The videotape provided an overview of diabetes, with emphasis on the concept of blood glucose; relationships between food, medications, exercise, and blood glucose levels; and blood glucose monitoring. Outcomes of videotape effectiveness were based on a 20-item knowledge test and interview data to assess acceptability of videotapes as a learning tool. Comparison of the knowledge test scores of the experimental group (those who viewed the tape before taking the knowledge test) with the control group (those who took the test before viewing the tape) produced a positive, moderate effect size of 0.61. Interviews with subjects indicated enthusiastic acceptance of the videotape as a means of transmitting diabetes information.
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Abstract
The clinical, hemodynamic, and pathologic features of hypertensive encephalopathy in two cats with reduced renal mass are described. The cats developed a progressive syndrome of lethargy, ataxia, blindness, stupor, and seizures following an abrupt increase in blood pressure associated with a surgical reduction in renal mass. The cats had severe gross brain edema, evidenced by cerebellar changes of caudal coning and cranial displacement over the corpora quadrigemina and cerebral changes of widening and flattening of the gyri. Histologically, interstitial edema was most pronounced in the cerebral white matter. Hypertensive vascular lesions were present as hyaline arteriolosclerosis in one cat and hyperplastic arteriolosclerosis in the other. Rare foci of parenchymal microhemorrhages and necrosis were also observed. Systemic hypertension (especially severe or rapidly developing) accompanied by neurologic signs and the pathologic findings of diffuse brain edema with cerebral arteriolosclerosis are consistent with an etiologic diagnosis of hypertensive encephalopathy.
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Affiliation(s)
- C A Brown
- Athens Diagnostic Laboratory, College of Veterinary Medicine, University of Georgia, Athens, GA 30602, USA.
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Afonso T, Giguère S, Rapoport G, Brown SA, Coleman AE. Attenuation of the blood pressure response to exogenous angiotensin I after oral administration of benazepril to healthy adult horses. Equine Vet J 2016; 49:358-362. [PMID: 27224673 DOI: 10.1111/evj.12593] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2016] [Accepted: 05/19/2016] [Indexed: 11/30/2022]
Abstract
BACKGROUND Benazepril has been shown to inhibit circulating angiotensin-converting enzyme (ACE) activity in horses but the optimal dosage is unknown. OBJECTIVES To determine the lowest tested dose of benazepril that results in ≥75% attenuation in the response of arterial blood pressure (BP) to exogenous angiotensin I (ANG-I) administration. STUDY DESIGN Prospective experimental study. METHODS A total of 5 healthy horses were instrumented for the direct measurement of BP. Each horse received 4 intragastric doses of benazepril (0.5, 1, 2 and 4 mg/kg bwt) with a washout period of 7 days between doses. Prior to and 2, 12 and 24 h after benazepril administration, each horse received intravenous (i.v.) boluses of ANG-I at 20, 60 and 200 ng/kg. Attenuation of the systolic arterial pressure (SBP) response to ANG-I and serum ACE activity were quantified and expressed as percentage of inhibition. RESULTS There was a significant effect of benazepril dose (P = 0.004) and time (P = 0.004) on the percentage of inhibition of the systolic pressor response to ANG-I. Regardless of benazepril dose, the percentage of inhibition was significantly greater 2 h after administration of benazepril compared with 12 and 24 h. At an ANG-I dose of 20 ng/kg, the percentage of inhibition after administration of benazepril at 1 mg/kg bwt (46.6 ± 18.9%) was significantly greater than that achieved after 0.5 mg/kg bwt (19 ± 14%) but not significantly different from that achieved at higher doses of benazepril. Benazepril doses ≥1 mg/kg bwt resulted in serum ACE inhibition of at least 90%. MAIN LIMITATIONS Small sample size and resulting low statistical power. CONCLUSIONS Attenuation of the rise in SBP in response to ANG-I after administration of benazepril is modest in horses despite adequate serum ACE inhibition. A dose of 1 mg/kg bwt would be recommended for future investigations of benazepril for the management of cardiovascular diseases in horses.
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Affiliation(s)
- T Afonso
- Department of Large Animal Medicine, College of Veterinary Medicine, University of Georgia, Athens, USA
| | - S Giguère
- Department of Large Animal Medicine, College of Veterinary Medicine, University of Georgia, Athens, USA
| | - G Rapoport
- Department of Small Animal Medicine and Surgery, College of Veterinary Medicine, University of Georgia, Athens, USA
| | - S A Brown
- Department of Small Animal Medicine and Surgery, College of Veterinary Medicine, University of Georgia, Athens, USA
| | - A E Coleman
- Department of Small Animal Medicine and Surgery, College of Veterinary Medicine, University of Georgia, Athens, USA
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Stringer S, Minică CC, Verweij KJH, Mbarek H, Bernard M, Derringer J, van Eijk KR, Isen JD, Loukola A, Maciejewski DF, Mihailov E, van der Most PJ, Sánchez-Mora C, Roos L, Sherva R, Walters R, Ware JJ, Abdellaoui A, Bigdeli TB, Branje SJT, Brown SA, Bruinenberg M, Casas M, Esko T, Garcia-Martinez I, Gordon SD, Harris JM, Hartman CA, Henders AK, Heath AC, Hickie IB, Hickman M, Hopfer CJ, Hottenga JJ, Huizink AC, Irons DE, Kahn RS, Korhonen T, Kranzler HR, Krauter K, van Lier PAC, Lubke GH, Madden PAF, Mägi R, McGue MK, Medland SE, Meeus WHJ, Miller MB, Montgomery GW, Nivard MG, Nolte IM, Oldehinkel AJ, Pausova Z, Qaiser B, Quaye L, Ramos-Quiroga JA, Richarte V, Rose RJ, Shin J, Stallings MC, Stiby AI, Wall TL, Wright MJ, Koot HM, Paus T, Hewitt JK, Ribasés M, Kaprio J, Boks MP, Snieder H, Spector T, Munafò MR, Metspalu A, Gelernter J, Boomsma DI, Iacono WG, Martin NG, Gillespie NA, Derks EM, Vink JM. Genome-wide association study of lifetime cannabis use based on a large meta-analytic sample of 32 330 subjects from the International Cannabis Consortium. Transl Psychiatry 2016; 6:e769. [PMID: 27023175 PMCID: PMC4872459 DOI: 10.1038/tp.2016.36] [Citation(s) in RCA: 110] [Impact Index Per Article: 13.8] [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] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/11/2015] [Accepted: 12/21/2015] [Indexed: 01/15/2023] Open
Abstract
Cannabis is the most widely produced and consumed illicit psychoactive substance worldwide. Occasional cannabis use can progress to frequent use, abuse and dependence with all known adverse physical, psychological and social consequences. Individual differences in cannabis initiation are heritable (40-48%). The International Cannabis Consortium was established with the aim to identify genetic risk variants of cannabis use. We conducted a meta-analysis of genome-wide association data of 13 cohorts (N=32 330) and four replication samples (N=5627). In addition, we performed a gene-based test of association, estimated single-nucleotide polymorphism (SNP)-based heritability and explored the genetic correlation between lifetime cannabis use and cigarette use using LD score regression. No individual SNPs reached genome-wide significance. Nonetheless, gene-based tests identified four genes significantly associated with lifetime cannabis use: NCAM1, CADM2, SCOC and KCNT2. Previous studies reported associations of NCAM1 with cigarette smoking and other substance use, and those of CADM2 with body mass index, processing speed and autism disorders, which are phenotypes previously reported to be associated with cannabis use. Furthermore, we showed that, combined across the genome, all common SNPs explained 13-20% (P<0.001) of the liability of lifetime cannabis use. Finally, there was a strong genetic correlation (rg=0.83; P=1.85 × 10(-8)) between lifetime cannabis use and lifetime cigarette smoking implying that the SNP effect sizes of the two traits are highly correlated. This is the largest meta-analysis of cannabis GWA studies to date, revealing important new insights into the genetic pathways of lifetime cannabis use. Future functional studies should explore the impact of the identified genes on the biological mechanisms of cannabis use.
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Affiliation(s)
- S Stringer
- Department of Complex Trait Genetics, VU Amsterdam, Center for Neurogenomics and Cognitive Research, Amsterdam, The Netherlands
- Department of Psychiatry, Academic Medical Centre, Amsterdam, The Netherlands
| | - C C Minică
- Department of Biological Psychology/Netherlands Twin Register, VU University, Amsterdam, The Netherlands
| | - K J H Verweij
- Department of Biological Psychology/Netherlands Twin Register, VU University, Amsterdam, The Netherlands
- Neuroscience Campus Amsterdam, Amsterdam, The Netherlands
- Department of Developmental Psychology and EMGO Institute for Health and Care Research, VU University, Amsterdam, The Netherlands
| | - H Mbarek
- Department of Biological Psychology/Netherlands Twin Register, VU University, Amsterdam, The Netherlands
| | - M Bernard
- The Hospital for Sick Children Research Institute, Toronto, Canada
| | - J Derringer
- Department of Psychology, University of Illinois Urbana-Champaign, Champaign, IL, USA
| | - K R van Eijk
- Department of Human Neurogenetics, Brain Center Rudolf Magnus, University Medical Center Utrecht, Utrecht, The Netherlands
| | - J D Isen
- Department of Psychology, University of Minnesota, Minneapolis, MN, USA
| | - A Loukola
- Department of Public Health, Hjelt Institute, University of Helsinki, Helsinki, Finland
| | - D F Maciejewski
- Department of Developmental Psychology and EMGO Institute for Health and Care Research, VU University, Amsterdam, The Netherlands
| | - E Mihailov
- Estonian Genome Center, University of Tartu, Tartu, Estonia
| | - P J van der Most
- Department of Epidemiology, University Medical Center Groningen, University of Groningen, Groningen, The Netherlands
| | - C Sánchez-Mora
- Psychiatric Genetics Unit, Vall d'Hebron Research Institute (VHIR), Universitat Autònoma de Barcelona, Barcelona, Spain
- Department of Psychiatry, Hospital Universitari Vall d'Hebron, Barcelona, Spain
- Biomedical Network Research Centre on Mental Health (CIBERSAM), Barcelona, Spain
| | - L Roos
- Twin Research and Genetic Epidemiology, King's College London, London, UK
| | - R Sherva
- Biomedical Genetics Department, Boston University School of Medicine, Boston, MA, USA
| | - R Walters
- Analytic and Translational Genetics Unit, Massachusetts General Hospital, Boston, MA, USA
- Stanley Center for Psychiatric Research, Broad Institute of MIT and Harvard, Cambridge, MA, USA
- Department of Medicine, Harvard Medical School, Boston, MA, USA
| | - J J Ware
- School of Social and Community Medicine, University of Bristol, Bristol, UK
- MRC Integrative Epidemiology Unit (IEU), University of Bristol, Bristol, UK
| | - A Abdellaoui
- Department of Biological Psychology/Netherlands Twin Register, VU University, Amsterdam, The Netherlands
| | - T B Bigdeli
- Department of Psychiatry, Virginia Institute for Psychiatric and Behavior Genetics, Virginia Commonwealth University, Richmond, VA, USA
| | - S J T Branje
- Research Centre Adolescent Development, Utrecht University, Utrecht, The Netherlands
| | - S A Brown
- Department of Psychology and Psychiatry, University of California San Diego, La Jolla, CA, USA
| | - M Bruinenberg
- The LifeLines Cohort Study, University of Groningen, Groningen, The Netherlands
| | - M Casas
- Department of Psychiatry, Hospital Universitari Vall d'Hebron, Barcelona, Spain
- Biomedical Network Research Centre on Mental Health (CIBERSAM), Barcelona, Spain
- Department of Psychiatry and Legal Medicine, Universitat Autònoma de Barcelona, Barcelona, Spain
| | - T Esko
- Estonian Genome Center, University of Tartu, Tartu, Estonia
| | - I Garcia-Martinez
- Psychiatric Genetics Unit, Vall d'Hebron Research Institute (VHIR), Universitat Autònoma de Barcelona, Barcelona, Spain
- Department of Psychiatry, Hospital Universitari Vall d'Hebron, Barcelona, Spain
| | - S D Gordon
- Genetic Epidemiology, Molecular Epidemiology and Neurogenetics Laboratories, QIMR Berghofer Medical Research Institute, Brisbane, QLD, Australia
| | - J M Harris
- Twin Research and Genetic Epidemiology, King's College London, London, UK
| | - C A Hartman
- Department of Psychiatry, University Medical Center Groningen, University of Groningen, Groningen, The Netherlands
| | - A K Henders
- Genetic Epidemiology, Molecular Epidemiology and Neurogenetics Laboratories, QIMR Berghofer Medical Research Institute, Brisbane, QLD, Australia
| | - A C Heath
- Department of Psychiatry, Washington University School of Medicine, St Louis, MO, USA
| | - I B Hickie
- Brain and Mind Research Institute, University of Sydney, Sydney, NSW, Australia
| | - M Hickman
- School of Social and Community Medicine, University of Bristol, Bristol, UK
| | - C J Hopfer
- Department of Psychiatry, University of Colorado Denver, Aurora, CO, USA
| | - J J Hottenga
- Department of Biological Psychology/Netherlands Twin Register, VU University, Amsterdam, The Netherlands
| | - A C Huizink
- Department of Developmental Psychology and EMGO Institute for Health and Care Research, VU University, Amsterdam, The Netherlands
| | - D E Irons
- Department of Psychology, University of Minnesota, Minneapolis, MN, USA
| | - R S Kahn
- Department of Human Neurogenetics, Brain Center Rudolf Magnus, University Medical Center Utrecht, Utrecht, The Netherlands
| | - T Korhonen
- Department of Public Health, Hjelt Institute, University of Helsinki, Helsinki, Finland
- Institute of Public Health and Clinical Nutrition, University of Eastern Finland, Kuopio, Finland
- Department of Mental Health and Substance Abuse Services, National Institute for Health and Welfare, Helsinki, Finland
| | - H R Kranzler
- Department of Psychiatry, University of Pennsylvania Perelman School of Medicine, Philadelphia, PA, USA
| | - K Krauter
- Department of Molecular, Cellular and Developmental Biology, University of Colorado Boulder, Boulder, CO, USA
| | - P A C van Lier
- Department of Developmental Psychology and EMGO Institute for Health and Care Research, VU University, Amsterdam, The Netherlands
| | - G H Lubke
- Department of Biological Psychology/Netherlands Twin Register, VU University, Amsterdam, The Netherlands
- Department of Psychology, University of Notre Dame, Notre Dame, IN, USA
| | - P A F Madden
- Department of Psychiatry, Washington University School of Medicine, St Louis, MO, USA
| | - R Mägi
- Estonian Genome Center, University of Tartu, Tartu, Estonia
| | - M K McGue
- Department of Psychology, University of Minnesota, Minneapolis, MN, USA
| | - S E Medland
- Genetic Epidemiology, Molecular Epidemiology and Neurogenetics Laboratories, QIMR Berghofer Medical Research Institute, Brisbane, QLD, Australia
| | - W H J Meeus
- Research Centre Adolescent Development, Utrecht University, Utrecht, The Netherlands
- Developmental Psychology, Tilburg University, Tilburg, The Netherlands
| | - M B Miller
- Department of Psychology, University of Minnesota, Minneapolis, MN, USA
| | - G W Montgomery
- Genetic Epidemiology, Molecular Epidemiology and Neurogenetics Laboratories, QIMR Berghofer Medical Research Institute, Brisbane, QLD, Australia
| | - M G Nivard
- Department of Biological Psychology/Netherlands Twin Register, VU University, Amsterdam, The Netherlands
| | - I M Nolte
- Department of Epidemiology, University Medical Center Groningen, University of Groningen, Groningen, The Netherlands
| | - A J Oldehinkel
- Interdisciplinary Center for Pathology and Emotion Regulation, University Medical Center Groningen, University of Groningen, Groningen, The Netherlands
| | - Z Pausova
- The Hospital for Sick Children Research Institute, Toronto, Canada
- Department of Physiology and Nutritional Sciences, University of Toronto, Toronto, ON, Canada
| | - B Qaiser
- Department of Public Health, Hjelt Institute, University of Helsinki, Helsinki, Finland
| | - L Quaye
- Twin Research and Genetic Epidemiology, King's College London, London, UK
| | - J A Ramos-Quiroga
- Department of Psychiatry, Hospital Universitari Vall d'Hebron, Barcelona, Spain
- Biomedical Network Research Centre on Mental Health (CIBERSAM), Barcelona, Spain
- Department of Psychiatry and Legal Medicine, Universitat Autònoma de Barcelona, Barcelona, Spain
| | - V Richarte
- Department of Psychiatry, Hospital Universitari Vall d'Hebron, Barcelona, Spain
| | - R J Rose
- Department of Psychological and Brain Sciences, Indiana University Bloomington, Bloomington, IN, USA
| | - J Shin
- The Hospital for Sick Children Research Institute, Toronto, Canada
| | - M C Stallings
- Department of Psychology and Neuroscience, Institute for Behavioral Genetics, University of Colorado Boulder, Boulder, CO, USA
| | - A I Stiby
- School of Social and Community Medicine, University of Bristol, Bristol, UK
| | - T L Wall
- Department of Psychiatry, University of California San Diego, La Jolla, CA, USA
| | - M J Wright
- Genetic Epidemiology, Molecular Epidemiology and Neurogenetics Laboratories, QIMR Berghofer Medical Research Institute, Brisbane, QLD, Australia
| | - H M Koot
- Department of Developmental Psychology and EMGO Institute for Health and Care Research, VU University, Amsterdam, The Netherlands
| | - T Paus
- Rotman Research Institute, Baycrest, Toronto, ON, Canada
- Department of Psychology and Psychiatry, University of Toronto, Toronto, ON, Canada
- Center for the Developing Brain, Child Mind Institute, New York, NY, USA
| | - J K Hewitt
- Department of Psychology and Neuroscience, Institute for Behavioral Genetics, University of Colorado Boulder, Boulder, CO, USA
| | - M Ribasés
- Psychiatric Genetics Unit, Vall d'Hebron Research Institute (VHIR), Universitat Autònoma de Barcelona, Barcelona, Spain
- Department of Psychiatry, Hospital Universitari Vall d'Hebron, Barcelona, Spain
- Biomedical Network Research Centre on Mental Health (CIBERSAM), Barcelona, Spain
| | - J Kaprio
- Department of Public Health, Hjelt Institute, University of Helsinki, Helsinki, Finland
- Department of Mental Health and Substance Abuse Services, National Institute for Health and Welfare, Helsinki, Finland
- Institute for Molecular Medicine Finland, University of Helsinki, Helsinki, Finland
| | - M P Boks
- Department of Human Neurogenetics, Brain Center Rudolf Magnus, University Medical Center Utrecht, Utrecht, The Netherlands
| | - H Snieder
- Department of Epidemiology, University Medical Center Groningen, University of Groningen, Groningen, The Netherlands
| | - T Spector
- Twin Research and Genetic Epidemiology, King's College London, London, UK
| | - M R Munafò
- School of Social and Community Medicine, University of Bristol, Bristol, UK
- UK Centre for Tobacco and Alcohol Studies and School of Experimental Psychology, University of Bristol, Bristol, UK
| | - A Metspalu
- Estonian Genome Center, University of Tartu, Tartu, Estonia
| | - J Gelernter
- Department of Psychiatry, Genetics, and Neurobiology, Yale University School of Medicine and VA CT, West Haven, CT, USA
| | - D I Boomsma
- Department of Biological Psychology/Netherlands Twin Register, VU University, Amsterdam, The Netherlands
- Neuroscience Campus Amsterdam, Amsterdam, The Netherlands
| | - W G Iacono
- Department of Psychology, University of Minnesota, Minneapolis, MN, USA
| | - N G Martin
- Genetic Epidemiology, Molecular Epidemiology and Neurogenetics Laboratories, QIMR Berghofer Medical Research Institute, Brisbane, QLD, Australia
| | - N A Gillespie
- Department of Psychiatry, Virginia Institute for Psychiatric and Behavior Genetics, Virginia Commonwealth University, Richmond, VA, USA
- Genetic Epidemiology, Molecular Epidemiology and Neurogenetics Laboratories, QIMR Berghofer Medical Research Institute, Brisbane, QLD, Australia
| | - E M Derks
- Department of Psychiatry, Academic Medical Centre, Amsterdam, The Netherlands
| | - J M Vink
- Department of Biological Psychology/Netherlands Twin Register, VU University, Amsterdam, The Netherlands
- Behavioural Science Institute, Radboud University, Nijmegen, The Netherlands
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Abstract
Chronic kidney disease (CKD) is the most common metabolic disease of domesticated cats, with most affected cats being geriatric (>12 years of age). The prevalence of CKD in cats exceeds that observed in dogs, and the frequency of the diagnosis of CKD in cats has increased in recent decades. Typical histologic features include interstitial inflammation, tubular atrophy, and fibrosis with secondary glomerulosclerosis. In contrast to people and dogs, primary glomerulopathies with marked proteinuria are remarkably rare findings in cats. Although a variety of primary renal diseases have been implicated, the disease is idiopathic in most cats. Tubulointerstitial changes, including fibrosis, are present in the early stages of feline CKD and become more severe in advanced disease. A variety of factors-including aging, ischemia, comorbid conditions, phosphorus overload, and routine vaccinations-have been implicated as factors that could contribute to the initiation of this disease in affected cats. Factors that are related to progression of established CKD, which occurs in some but not all cats, include dietary phosphorus intake, magnitude of proteinuria, and anemia. Renal fibrosis, a common histologic feature of aged feline kidneys, interferes with the normal relationship between peritubular capillaries and renal tubules. Experimentally, renal ischemia results in morphologic changes similar to those observed in spontaneous CKD. Renal hypoxia, perhaps episodic, may play a role in the initiation and progression of this disease.
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Affiliation(s)
- C A Brown
- Athens Veterinary Diagnostic Laboratory, College of Veterinary Medicine, University of Georgia, Athens, GA, USA
| | - J Elliott
- Department of Comparative Biomedical Sciences, Royal Veterinary College, University of London, London, UK
| | - C W Schmiedt
- Department of Small Animal Medicine and Surgery, College of Veterinary Medicine, University of Georgia, Athens, GA, USA
| | - S A Brown
- Department of Physiology and Pharmacology, College of Veterinary Medicine, University of Georgia, Athens, GA, USA
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Abstract
BACKGROUND Health and life expectancy for people with hemophilia have improved significantly in recent years, but we face new challenges, especially in the context of resource-constrained health services. AIM This paper aims to highlight such challenges and propose practical solutions. METHODS Nine hemophilia specialists from Australia and New Zealand reached consensus on areas of greatest need for improvement in hemophilia care in these countries, based on clinical experience and published data, and agreed on how to address these. RESULTS Demography, optimizing treatment and assessing treatment success were identified as broad areas of challenge which included: comorbidities in ageing patients; transitioning from pediatric to adult care; equity of care for remote populations; weight-based dosing in obese patients; tailoring prophylaxis; accurate diagnosis of acute joint pain; managing chronic arthropathy; providing psychosocial support; consistency in definitions and assessment; and quantifiable outcome measures. Practice points included increased cross-specialty coordination and including psychologists and rheumatologists as part of comprehensive care teams; close collaboration between pediatric and adult centers to facilitate transition of care; systems such as telehealth that ensure continuity of care for remote populations; using pharmacokinetic data to tailor therapy; rapid and accurate diagnosis of acute joint pain; using data from bleeding registries to assess treatment effects and help with service planning; and ensuring consistency through benchmarking and standardization of HTCs. SUMMARY Achieving treatment equity, optimal outcomes and cost savings may be possible through investing in national governance structures, expanding the comprehensive model of care and implementing innovative solutions tailored to local needs.
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Affiliation(s)
- S A Brown
- a a Royal Children's Hospital Haematology , Brisbane , Queensland , Australia
- b b Pathology Queensland , Brisbane , Queensland , Australia
| | - J Phillips
- c c Haematology Department , Wellington Hospital , Wellington , New Zealand
| | - C Barnes
- d d Haemophilia Treatment Centre, Royal Children's Hospital , Parkville , Victoria , Australia
| | - J Curtin
- e e Haematology Department , The Children's Hospital at Westmead , Westmead , New South Wales , Australia
| | - S McRae
- f f Adult Haemophilia Treatment Centre, Royal Adelaide Hospital , Adelaide , South Australia , Australia
| | - P Ockelford
- g g Adult Haemophilia Treatment Centre, Auckland Hospital , Auckland , New Zealand
| | - J Rowell
- h h Haemophilia Treatment Centre, Royal Brisbane and Women's Hospital , Brisbane , Queensland , Australia
| | - M P Smith
- i i Canterbury District Health Board, Christchurch Hospital , Christchurch , New Zealand
| | - S Dunkley
- j j Haemophilia Treatment Centre, Royal Prince Alfred Hospital , Camperdown , New South Wales , Australia
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Abstract
The diagnosis and management of bleeding disorders is made difficult by the complexity and variety of disorders, clinical symptoms and bleeding type and severity. von Willebrand disease (VWD) and platelet disorders are disorders of primary haemostasis and together represent the most common inherited bleeding disorders. In this article, we describe the diagnosis of VWD and platelet disorders and the treatment options for VWD.
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Affiliation(s)
- E J Favaloro
- Diagnostic Haemostasis, Haematology Department, Institute of Clinical Pathology and Medical Research (ICPMR), Pathology West, Westmead Hospital, Westmead, NSW, Australia
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Bugbee AC, Coleman AE, Wang A, Woolcock AD, Brown SA. Telmisartan treatment of refractory proteinuria in a dog. J Vet Intern Med 2014; 28:1871-4. [PMID: 25270397 PMCID: PMC4895629 DOI: 10.1111/jvim.12471] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2014] [Revised: 05/27/2014] [Accepted: 08/27/2014] [Indexed: 01/13/2023] Open
Affiliation(s)
- A C Bugbee
- Department of Small Animal Medicine & Surgery, College of Veterinary Medicine, University of Georgia, Athens, GA
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23
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Zobel AM, Brown SA. Dermatitis-inducing furanocoumarins on leaf surfaces of eight species of Rutaceous and Umbelliferous plants. J Chem Ecol 2013; 16:693-700. [PMID: 24263585 DOI: 10.1007/bf01016480] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/03/1989] [Accepted: 04/13/1989] [Indexed: 10/25/2022]
Abstract
Eight species of Rutaceae or Umbelliferae, known to cause or suspected of causing photophytodermatitis, had the linear furanocoumarins psoralen, bergapten, and xanthotoxin on their leaf surfaces, in concentrations varying from 0.014 to 1800 /gmg/g fresh weight, equivalent to 0.17-56% of the total leaf concentration. The higher percentage generally observed for spring leaves compared to autumn leaves suggests a higher rate of transfer of these furanocoumarins to the surface in the younger leaves. Among the plants studied,Ruta graveolens had the highest surface concentrations of all three furanocoumarins. The relatively high effectiveness in causing dermatitis of some species with low surface concentrations may be explained by a more effective mechanism of transfer of the furanocoumarins to the skin. A role in the defense of the plant is suggested by their accumulation on the plant surface.
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Affiliation(s)
- A M Zobel
- Department of Chemistry, Trent University, K9J 7B8, Peterborough, Ontario, Canada
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24
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Brown SA, Chime SA, Attama AA, Agu CI, Onunkwo GC. In vitro and In vivo Characterisation of Piroxicam-Loaded Dika Wax Lipospheres. TROP J PHARM RES 2013. [DOI: 10.4314/tjpr.v12i1.6] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
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25
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Kamens HM, Corley RP, McQueen MB, Stallings MC, Hopfer CJ, Crowley TJ, Brown SA, Hewitt JK, Ehringer MA. Nominal association with CHRNA4 variants and nicotine dependence. Genes Brain Behav 2013; 12:297-304. [PMID: 23350800 DOI: 10.1111/gbb.12021] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/07/2012] [Revised: 11/06/2012] [Accepted: 01/10/2013] [Indexed: 01/05/2023]
Abstract
Nicotine binds to nicotinic acetylcholine receptors and studies in animal models have shown that α4β2 receptors mediate many behavioral effects of nicotine. Human genetics studies have provided support that variation in the gene that codes for the α4 subunit influences nicotine dependence (ND), but the evidence for the involvement of the β2 subunit gene is less convincing. In this study, we examined the genetic association between variation in the genes that code for the α4 (CHRNA4) and β2 (CHRNB2) subunits of the nicotinic acetylcholine receptor and a quantitative measure of lifetime DSM-IV ND symptom counts. We performed this analysis in two longitudinal family-based studies focused on adolescent antisocial drug abuse: the Center on Antisocial Drug Dependence (CADD, N = 313 families) and Genetics of Antisocial Drug Dependence (GADD, N = 111 families). Family-based association tests were used to examine associations between 14 single nucleotide polymorphisms (SNPs) in CHRNA4 and CHRNB2 and ND symptoms. Symptom counts were corrected for age, sex and clinical status prior to the association analysis. Results, when the samples were combined, provided modest evidence that SNPs in CHRNA4 are associated with ND. The minor allele at both rs1044394 (A; Z = 1.988, P = 0.047, unadjusted P-value) and rs1044396 (G; Z = 2.398, P = 0.017, unadjusted P-value) was associated with increased risk of ND symptoms. These data provide suggestive evidence that variation in the α4 subunit of the nicotinic acetylcholine receptor may influence ND liability.
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Affiliation(s)
- H M Kamens
- Institute for Behavioral Genetics, University of Colorado Boulder, Boulder, CO, USA
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26
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Villarino N, Lesman S, Fielder A, García-Tapia D, Cox S, Lucas M, Robinson J, Brown SA, Martín-Jiménez T. Pulmonary pharmacokinetics of tulathromycin in swine. Part I: Lung homogenate in healthy pigs and pigs challenged intratracheally with lipopolysaccharide of Escherichia coli. J Vet Pharmacol Ther 2012; 36:329-39. [PMID: 23072251 DOI: 10.1111/jvp.12016] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/22/2012] [Revised: 07/12/2012] [Accepted: 08/17/2012] [Indexed: 11/28/2022]
Abstract
The objective of the study was to assess the pharmacokinetics of tulathromycin in lung tissue homogenate (LT) and plasma from healthy and lipopolysaccharide (LPS)-challenged pigs. Clinically healthy pigs were allocated to two dosing groups of 36 animals each (group 1 and 2). All animals were treated with tulathromycin (2.5 mg/kg). Animals in group 2 were also challenged intratracheally with LPS from Escherichia coli (LPS-Ec) 3 h prior to tulathromycin administration. Blood and LT samples were collected from all animals during 17-day post-tulathromycin administration. For LT, one sample from the middle (ML) and caudal lobes (CL) was taken. The concentration of tulathromycin was significantly lower in the ML after the intratracheal administration of LPS-E. coli (P < 0.02). In healthy pigs and LPS-challenged animals, the distribution of the drug into the lungs was rapid and persisted at high levels for 17-day postadministration. The distribution of the drug within the lung seems to be homogenous, at least between the middle and caudal lobes within dosing groups. The concentration versus time profile of the drug and pharmacokinetic parameters in two different lung areas (middle and caudal lobe) were consistent within the groups. The clinical significance of these findings is unknown.
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Affiliation(s)
- N Villarino
- Department of Microbiology, The University of Tennessee, Knoxville, TN 37996, USA
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27
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Anderson DK, Reier PJ, Wirth Iii ED, Theele DP, Mareci T, Brown SA. Delayed grafting of fetal CNS tissue into chronic compression lesions of the adult cat spinal cord. Restor Neurol Neurosci 2012; 2:309-25. [PMID: 21551618 DOI: 10.3233/rnn-1991-245621] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
This review summarizes a series of experiments involving transplants of embryonic feline CNS tissue into chronic compression lesions of the adult cat spinal cord. Fetal spinal cord (FSC), caudal brainstem (BSt), neocortex (NCx) or a combination of either FSC/NCx or FSC/BSt was transplanted as solid pieces or as a suspension of dissociated cells into the developed cystic cavities produced by static-load compression trauma 2-10 weeks prior to grafting. All cats were immunosuppressed with cyclosporin A and their locomotor function was assessed for 6-30 weeks. Following the period of evaluation, all recipients were perfused with fixative and tissue specimens, taken at the transplantation site, were processed for general histological and/or immunocytochemical analysis. Viable graft tissue was found in all animals with the exception of two cats which showed active rejection of their transplants. All of the viable intraspinal grafts were extensively vascularized and did not show any signs of imminent or on-going tissue rejection. Fetal cat CNS grafts showed an extended maturational phase in that features of immature neural tissue (e.g. a paucity of myelination) were still seen even 6-9 weeks after transplantation. By 20-30 weeks, FSC and BSt grafts had attained a more advanced stage of maturation. Transplants in these chronic lesions were extensively blended with both the gray and white matter of the host spinal cord and could be visualized by magnetic resonance imaging (MRI). MRI could also detect regions of cavitation at the graft-host interface, as well as within some transplants. While preliminary evidence from behavioral studies suggest that the FSC and BSt grafts may improve or spare locomotor function in some recipients, a more rigorous analysis of post-grafting locomotor function is required to determine conclusively the functionality of these transplants.
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Affiliation(s)
- D K Anderson
- Cincinnati Veterans Affairs Medical Center and Departments of Neurology and Physiology/Biophysics, University of Cincinnati College of Medicine, Cincinnati, OH 45220 (U.S.A.)
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Villarino N, Garcia-Tapia D, Lesman S, Lucas M, Robinson J, Brown SA, Martin-Jimenez T. An acute reversible experimental model of pneumonia in pigs: time-related histological and clinical signs changes. J Vet Pharmacol Ther 2012; 36:241-7. [PMID: 22632136 DOI: 10.1111/j.1365-2885.2012.01415.x] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The objective of this study was to evaluate the long-term survival rates, clinical response, and lung gross and microscopic changes in pigs treated intratracheally with lipopolysaccharide of Escherichia coli 0111:B4 (LPS-Ec). Healthy pigs were randomly allocated to three groups: (i) no-LPS-Ec (n=1), (ii) LPS-Ec-T1 (1 mg/mL, 10 mL/pig) (n=7), and (iii) LPS-Ec-T2 (0.5 mg/mL, 10 mL/pig) (n=6). Two pigs from each dose group were euthanized at 24 (n=3 for T1), 48 and 144 h post-LPS-Ec challenge. LPS-Ec-treated animals showed macroscopic lesions in middle lobes of the lung. A reversible recruitment of macrophages and neutrophils was observed at 24, 48, and 144 h post-LPS-Ec challenge. The highest cellular infiltration level was observed at 24 h after challenge. The highest clinical scores were evident in both experimental dose levels within 3 and 5 h after LPS-Ec administration. Administration of LPS-Ec, under the conditions evaluated, can be used to induce a reproducible model of acute pulmonary inflammation in pigs.
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Affiliation(s)
- N Villarino
- Department of Biomedical and Diagnostic Sciences, College of Veterinary Medicine, University of Tennessee, Knoxville, TN 37996, USA
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29
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Abstract
Many natural structures have fractal geometries that exhibit useful functional properties. These properties, which exploit the recurrence of patterns at increasingly small scales, are often desirable in applications and, consequently, fractal geometry is increasingly employed in diverse technologies ranging from radio antennae to storm barriers. In this paper, we explore the application of fractal geometry to electrical devices. First, we lay the foundations for the implementation of fractal devices by considering diffusion-limited aggregation (DLA) of atomic clusters. Under appropriate growth conditions, atomic clusters of various elements form fractal patterns driven by DLA. We perform a fractal analysis of both simulated and physical devices to determine their spatial scaling properties and demonstrate their potential as fractal circuit elements. Finally, we simulate conduction through idealized and DLA fractal devices and show that their fractal scaling properties generate novel, nonlinear conduction properties in response to depletion by electrostatic gates.
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Affiliation(s)
- M S Fairbanks
- Department of Physics, University of Oregon, Eugene, OR 97403, USA.
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30
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Brown SA. Chemistry of Lignification: Biochemical research on lignins is yielding clues to the structure and formation of these complex polymers. Science 2010; 134:305-13. [PMID: 17819301 DOI: 10.1126/science.134.3475.305] [Citation(s) in RCA: 48] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
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Thompson JS, Chu Y, Glass JF, Brown SA. Absence of IL-23p19 in donor allogeneic cells reduces mortality from acute GVHD. Bone Marrow Transplant 2010; 45:712-22. [PMID: 19718070 DOI: 10.1038/bmt.2009.215] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2008] [Revised: 06/17/2009] [Accepted: 07/09/2009] [Indexed: 02/05/2023]
Abstract
The p19 dimer of interleukin 23 (IL-23) has been reported to have a major role in the pathogenesis of many experimental and clinical autoimmune diseases and may also have a prominent role in transplantation. We reasoned that deficiency of p19 in the allogeneic donor transplant might reduce the inflammation caused by acute GVHD (aGVHD). The major histocompatibility complex-2 (H2(d)) BALB/c mice were subjected to 8.5 Gy TBI, followed by transplantation with 10 x 10(6) BM and 2.5 x 10(6) spleen cells from H2(d) BALB/c, H2(b) C57Bl/6 (B6) or H2(b) p19-/- donors. In all, 75% of the p19-/- transplanted mice survived, compared with only 12.5% of the B6 transplanted mice. This superior survival is correlated with significantly less severe aGVHD, absence of p19 after transplantation, less upregulation of mRNA and lower serum levels of IL-17 as compared with the B6 transplants. TBI alone significantly upregulated transforming growth factor-beta (TGF-beta), IL-6 and p19 mRNA levels in host BALB/c mice, possibly providing the milieu to induce IL-17 in p19-/- donor cells. IL-22, another cytokine, the induction of which in T-helper 17 (Th17) cells is supported by p19, was upregulated in BALB/c hosts but not in transplanted B6 or p19 donor cells, and may not have had a major role in modifying aGVHD.
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Affiliation(s)
- J S Thompson
- Veterans Affairs Medical Center, Department of Internal Medicine, University of Kentucky, Lexington, KY 40502, USA.
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Meyer S, Giguère S, Rodriguez R, Zielinski RJ, Grover GS, Brown SA. Pharmacokinetics of intravenous ceftiofur sodium and concentration in body fluids of foals. J Vet Pharmacol Ther 2010; 32:309-16. [PMID: 19614835 DOI: 10.1111/j.1365-2885.2008.01041.x] [Citation(s) in RCA: 42] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
The objectives of this study were to determine pharmacokinetics of intravenous (i.v.) ceftiofur in foals, to compare ultra-high performance liquid chromatography tandem mass spectometry (UPLC-MS/MS) and microbiologic assay for the measurement of ceftiofur concentrations, and to determine the minimum inhibitory concentration (MIC) of ceftiofur against common equine bacterial pathogens. In a cross-over design, ceftiofur sodium was administered i.v. to six foals (1-2 days-of-age and 4-5 weeks-of-age) at dosages of 5 and 10 mg/kg. Subsequently, five doses of ceftiofur were administered i.v. to six additional foals between 1 and 5 days of age at a dose of 5 mg/kg q 12 h. Concentrations of desfuroylceftiofur acetamide (DCA), the acetamide derivative of ceftiofur and desfuroylceftiofur-related metabolites were measured in plasma, synovial fluid, urine, and CSF by use of UPLC-MS/MS. A microbiologic assay was used to measure ceftiofur activity for a subset of plasma samples. Following i.v. administration of ceftiofur at a dose of 5 mg/kg to 1-2 day-old foals, DCA had a t(1/2) of 7.8 +/- 0.1 h, a body clearance of 74.4 +/- 8.4 mL/h/kg, and an apparent volume of distribution of 0.83 +/- 0.09 L/kg. After multiple i.v. doses at 5 mg/kg, DCA concentrations in CSF were significantly lower than concurrent plasma concentrations. Ceftiofur activity using a microbiologic assay significantly underestimated plasma concentrations of DCA. The MIC of ceftiofur required to inhibit growth of 90% of isolates of Escherichia coli, Pasteurella spp, Klebsiella spp, and beta-hemolytic streptococci was <0.5 microg/mL. Intravenous administration of ceftiofur sodium at the rate of 5 mg/kg every 12 h would provide sufficient coverage for the treatment of susceptible bacterial isolates.
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Affiliation(s)
- S Meyer
- Department of Large Animal Clinical Sciences, College of Veterinary Medicine, University of Florida, Gainesville, FL 32610, USA
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Abstract
Tin oxide (SnO(2)) cluster nanowires have been fabricated using atomic clusters as building blocks. Nanowires with widths of less than 100 nm were defined using electron beam lithography followed by deposition of Sn clusters which were subsequently thermally oxidized. The cluster nanowires were used to fabricate field effect transistors. The transistors were n-type and demonstrated a clear size-dependent behaviour. With zero gate bias the narrowest wires were depleted, both the carrier concentration and the conduction quickly increasing with wire width. This behaviour is attributed to the formation of a surface depletion region caused by Fermi level pinning. The width of the depletion region was estimated using the carrier concentration calculated from the transistor threshold voltages. The change in the wire conductance with UV illumination was also investigated. Illumination with 365 nm light increases the conduction by up to 40 times. This is attributed to a combination of an increase in carriers due to photo-desorption of oxygen from the surface of the wires and an increase in the mobility due to a reduction of inter-grain potential barrier height.
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Affiliation(s)
- E J Boyd
- The MacDiarmid Institute of Advanced Materials and Nanotechnology, Department of Physics and Astronomy, University of Canterbury, Christchurch 8140, New Zealand
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Maslov LN, Barzakh EI, Krylatov AV, Brown SA, Oeltgen PR, Govindaswami M, Chernysheva GA, Solenkova NV, Lishmanov AI, Tsibul'nikov SI, Krieg T, Zhang E. [Significance of opioid receptors in regulation of cardiac tolerance in pathogenic impact of long-term ischemia-reperfusion in vivo]. Ross Fiziol Zh Im I M Sechenova 2009; 95:563-572. [PMID: 19639880] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/28/2023]
Abstract
The study aimed at investigation of the role of opioid receptor (OR) in regulation of cardiac tolerance to ischemia-reperfusion. Opioid receptor ligands and inhibitors were administered in vivo prior to coronary artery occlusion (45 min) and reperfusion (2 hrs). Occurring infraction size/area at risk (IS/AAR) ratio was determined. Pretreatment with the micro-OR agonists DAMGO and dermorphin H exerted no effect on the IS/AAR ratio. Activation of delta 1-OR by DPDPE did not alter cardiac tolerance in ischemia-reperfusion either. Pretreatment with the delta 2-OR agonists deltorphin D and deltorphin E or ORL1 receptor agonist nociceptin exerted no effect on the IS/AAR ratio. Stimulation of K-OR by selective agonists did not modify cardiac tolerance to ischemia-reperfusion. The delta 2-OR agonist deltorphin II significantly reduced the IS/AAR index. This effect was prevented by treatment with naltrexone, naloxone methiodide and the delta 2-OR antagonist naltriben but not by the delta 1-OR antagonist BNTX. The infarction-limiting effect of deltorphin II was also abolished by inhibition of protein kinase C (PKC) and mitochondrial Katp channels. Thus, the agonists of micro, delta 1, kappa, and ORL1 receptors in used doses did not affect cardiac tolerance in ischemia-reperfusion injury in vivo. The peripheral delta 2-OR activation induces infarction size reduction. Its infarction-reducing effect of deltorphin II is mediated via PKC activation and mitochondrial Katp, channel opening.
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Emeje MO, Eni-ike NE, Brown SA, Ofoefule SI. Preparation andIn vitrorelease of hydrochlorothiazide from gellan beads produced by ionotropic gelation. Asian J Pharm 2009. [DOI: 10.4103/0973-8398.55055] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
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Affiliation(s)
- S A Brown
- Internal Medicine and Critical Care Department, VCA Veterinary Referral Associates, North Potomac, MD 20878, USA.
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Forchuk C, Brown SA, Schofield R, Jensen E. Perceptions of health and health service utilization among homeless and housed psychiatric consumer/survivors. J Psychiatr Ment Health Nurs 2008; 15:399-407. [PMID: 18454826 DOI: 10.1111/j.1365-2850.2007.01246.x] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.4] [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] [Indexed: 11/27/2022]
Abstract
Homelessness has a direct impact on health. Homeless individuals report several barriers to accessing health care. Although research exists regarding the utilization of health services for homeless and housed psychiatric consumer/survivors, few studies have compared the perceived health and service utilization of these two groups. The objective of this study was to determine whether or not differences exist between the utilization of health services and the perceptions of health of homeless and housed psychiatric consumer/survivors in London, Ontario, Canada. It was hypothesized that differences would exist between homeless and housed psychiatric consumer/survivors on all health-related variables examined. A secondary analysis of quantitative data was conducted in a Community-University Research Alliance on Mental Health and Housing project funded by the Social Sciences and Humanities Research Council of Canada. Key findings include significant differences in the characteristics of each population, the use of health services and their perceptions of health. Implications for practice and policy are discussed.
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Affiliation(s)
- C Forchuk
- School of Nursing, University of Western Ontario, London, ON, Canada.
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Ponsonby AL, Brown SA, Kearns LS, MacKinnon JR, Scotter LW, Cochrane JA, Mackey DA. The association between maternal smoking in pregnancy, other early life characteristics and childhood vision: the Twins Eye Study in Tasmania. Ophthalmic Epidemiol 2008; 14:351-9. [PMID: 18161608 DOI: 10.1080/01658100701486467] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
Abstract
PURPOSE To investigate the association between maternal smoking in pregnancy, early-life environment and childhood vision. METHODS Twin and triplet children enrolled in the Twins Eye Study in Tasmania underwent a comprehensive ophthalmic examination and their parents/guardians retrospectively answered a questionnaire regarding crawling, walking and other measures. A subset of these twins was also in the Tasmanian Infant Health Survey, which prospectively collected data on antenatal smoking, gestation, birth weight and other factors. RESULTS The mean age of the 346 individuals (172 multiple birth sets) at the time of examination was 9.25+/-2.4 years. Mean unaided visual acuity was 0.0 (6/6). The mean spherical equivalent was +0.87D, and decreased with increasing child age (p<0.01). A prospective analysis, accounting for birth set clustering and relevant confounders, showed increasing levels of maternal smoking in the third trimester was associated with poor stereoacuity on the Titmus test (worse (>) than 100'', p=0.05) and Lang test (p=0.001) and also with the presence of esotropia (p=0.02). These associations persisted after adjustment for infant postnatal smoke exposure at one month of age. Poor stereoacuity on Titmus stereo test circles was associated with late age of first crawling (RR=1.23 (1.06, 1.42) p=0.005 per month) and late age of first walking (RR 1.18 (1.05, 1.22) p=0.001 per month). CONCLUSIONS Antenatal smoking was independently associated with poor stereovision and the presence of esotropia. Poor stereoacuity may be associated with delayed age at first crawling or walking.
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Affiliation(s)
- A L Ponsonby
- Menzies Institute, University of Tasmania, Australia
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Abstract
We have prepared sensitive hydrogen and ammonia sensors from thin films of tin nanoclusters with diameters between 3 and 10 nm. By baking the samples at 200 °C in ambient air the clusters were oxidized, resulting in very stable films of tin oxide clusters with similar diameters to the original Sn clusters. By monitoring the electrical resistance, it is shown that the cluster films are highly responsive to hydrogen and ammonia at relatively low temperatures, thereby making them attractive for commercial applications in which low power consumption is required. Doping of the films by depositing Pd on top of the clusters resulted in much improved sensor response and response times. It is shown that optimal sensor properties are achieved for very thin cluster films (a few monolayers of clusters).
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Affiliation(s)
- A Lassesson
- Nano Cluster Devices Ltd, Rutherford Building, University of Canterbury, Christchurch, New Zealand
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Pagani L, Waldmeier L, Meier F, Izakovic J, Cajochen C, Wirz-Justice A, Brown SA, Eckert A. Molecular circadian rhythms in humans: effects of age. Pharmacopsychiatry 2007. [DOI: 10.1055/s-2007-991843] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
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Chalmers EA, Brown SA, Keeling D, Liesner R, Richards M, Stirling D, Thomas A, Vidler V, Williams MD, Young D. Early factor VIII exposure and subsequent inhibitor development in children with severe haemophilia A. Haemophilia 2007; 13:149-55. [PMID: 17286767 DOI: 10.1111/j.1365-2516.2006.01418.x] [Citation(s) in RCA: 134] [Impact Index Per Article: 7.9] [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: 11/28/2022]
Abstract
Recent reports have suggested that the incidence of inhibitors in haemophilia is the highest in those first exposed to factor VIII under 6 months of age. In this study, we investigated inhibitor development in children first exposed to FVIII as neonates and also examined the effect of other genetic and environmental variables. Three hundred and forty-eight children with severe haemophilia A were investigated. Inhibitors developed in 68 of 348 (20%), with 34 of 348 (10%) high titre inhibitors. The incidence in relation to initial FVIII exposure was: <1 month nine of 35 (26%), 1-6 months 13 of 51 (25%), 6-12 months 27 of 130 (21%), 12-18 months 13 of 66 (20%) and >18 months six of 66 (9%). While we observed a significant difference in inhibitor development and age at first exposure across all age groups (P = 0.018), no significant difference was observed in children treated at different time points during the first year of life (P = 0.44). Similar results were obtained for high titre inhibitors. There was also no difference in the incidence of inhibitors in relation to initial FVIII exposure in a subgroup of 144 children with the intron 22 mutation. Inhibitors developed more frequently in those initially treated with recombinant when compared with plasma-derived FVIII (P = 0.006) and in those with a major molecular defect (P = 0.009). In this study, exposure to FVIII during the neonatal period was not associated with a higher incidence of inhibitors than those treated later during the first year of life. Initial treatment with recombinant FVIII and the presence of a major molecular defect were the most important variables affecting inhibitor development.
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Brown SA, Boucher JF, Hubbard VL, Prough MJ, Flook TF. The comparative plasma pharmacokinetics of intravenous cefpodoxime sodium and oral cefpodoxime proxetil in beagle dogs. J Vet Pharmacol Ther 2007; 30:320-6. [PMID: 17610405 DOI: 10.1111/j.1365-2885.2007.00873.x] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [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: 11/27/2022]
Abstract
The pharmacokinetic properties of cefpodoxime, and its prodrug, cefpodoxime proxetil, were evaluated in two separate studies, one following intravenous (i.v.) administration of cefpodoxime sodium and the second after oral (p.o.) administration of cefpodoxime proxetil to healthy dogs. After cefpodoxime administration, serial blood samples were collected and plasma concentrations were determined by high performance liquid chromatography (HPLC). A single i.v. administration of cefpodoxime sodium at a dose of 10 mg cefpodoxime/kg body weight resulted in a cefpodoxime average maximum plasma concentration (Cmax) of 91 (+/-17.7) microg/mL, measured at 0.5 h after drug administration, an average half-life (t1/2) of 4.67 (+/-0.680) h, an average AUC(0-infinity) of 454 (+/-83.1) h.microg/mL, an average V(d(ss)) of 151 (+/-27) mL/kg, an average Cl(B) of 22.7 (+/-4.2) mL/h/kg and an average MRT(0-infinity) of 5.97 (+/-0.573) h. When dose normalized to 10 mg cefpodoxime/kg body weight, cefpodoxime proxetil administered orally resulted in Cmax of 17.8 +/- 11.4 microg/mL for the tablet formulation and 20.1 +/- 6.20 microg/mL for the suspension formulation and an average AUC(0-LOQ) of 156 (+/-76.1) h.microg/mL for the tablet formulation and 162 (+/-48.6) h.microg/mL for the suspension formulation. Relative bioavailability of the two oral formulations was 1.04 (suspension compared with tablet), whereas the absolute bioavailability of both oral formulations was estimated to be approximately 35-36% in the cross-study comparison with the i.v. pharmacokinetics. Combined with previous studies, these results suggest that a single daily oral dose of 5-10 mg cefpodoxime/kg body weight as cefpodoxime proxetil maintains plasma concentrations effective for treatment of specified skin infections in dogs.
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Affiliation(s)
- S A Brown
- Veterinary Medicine Research & Development, Pfizer Animal Health, Kalamazoo, MI 49001, USA.
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Stevens KJ, Ingham B, Toney MF, Brown SA, Partridge J, Ayesh A, Natali F. Structure of oxidized bismuth nanoclusters. Acta Crystallogr B Struct Sci 2007; 63:569-76. [PMID: 17641426 DOI: 10.1107/s0108768107024652] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/22/2007] [Accepted: 05/19/2007] [Indexed: 11/10/2022]
Abstract
Synchrotron X-ray diffraction has determined that β-Bi2O3 is the dominant oxide phase covering hexagonal bismuth nanoclusters produced in an inert gas aggregation source. Simulated Debye–Scherrer patterns have indicated that the oxide is 20 ± 5 Å thick on average, at the surface of 320 ± 40 Å diameter clusters. A Williamson–Hall analysis of the peak broadening was used to measure the non-uniform strain in clusters. The oxidized clusters were in −0.11 ± 0.06% uniform compressive strain compared with other clusters without oxides detectable by X-ray diffraction which only have a small tensile uniform strain. High-resolution transmission electron microscopy (HRTEM) and multislice image simulations indicated a β-Bi2O3 thickness of 20–50 Å. The HRTEM micrographs show the relative orientation between the oxide and the cluster core.
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Affiliation(s)
- K J Stevens
- MPT Solutions Ltd, PO Box 38-096, Lower Hutt, New Zealand.
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Abstract
Angiotensin-converting enzyme (ACE) inhibitors represent one of the most commonly used categories of drugs in canine and feline medicine. ACE inhibitors currently approved for use in veterinary medicine are benazepril, enalapril, imidapril and ramipril. They are all pro-drugs administered by oral route. A physiologically based model taking into account the saturable binding to ACE has been developed for pharmacokinetic analysis. The bioavailability of the active compounds from their respective pro-drug is low. The active metabolites are eliminated by renal, hepatorenal or biliary excretion, according to the drug. The elimination half-life of the free fraction of the active compounds is very short (ranging from approximately 10 min to 2 h). ACE inhibitors are generally well tolerated. Benazepril, enalapril, imidapril and ramipril are approved for dogs with chronic heart failure (CHF). The efficacy of ACE inhibitors has been convincingly demonstrated in dogs with CHF, especially in those with chronic valvular disease. In such clinical settings, ACE inhibitors improve hemodynamics and clinical signs, and increase survival time. In cats with cardiovascular disease, little information is available except for reports of some benefit in cats with hypertrophic cardiomyopathy in two non-controlled investigations. ACE inhibitors have also a mild to moderate hypotensive effect. There is also evidence to recommend ACE inhibitors in dogs and cats with chronic renal failure (CRF). They decrease the glomerular capillary pressure, have antiproteinuric effects, tend to delay the progression of CRF and to limit the extent of renal lesions.
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Affiliation(s)
- H P Lefebvre
- UMR 181 INRA-ENVT Physiopathologie et Toxicologie Expérimentales, National Veterinary School, Toulouse cedex 03, France.
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Conn VS, Hafdahl AR, Mehr DR, LeMaster JW, Brown SA, Nielsen PJ. Metabolic effects of interventions to increase exercise in adults with type 2 diabetes. Diabetologia 2007; 50:913-21. [PMID: 17342472 DOI: 10.1007/s00125-007-0625-0] [Citation(s) in RCA: 75] [Impact Index Per Article: 4.4] [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] [Received: 02/14/2006] [Accepted: 01/16/2007] [Indexed: 01/15/2023]
Abstract
AIMS/HYPOTHESIS The aim of this meta-analysis was to integrate the results of primary research testing the effect of diabetes self-management interventions that included recommendations to increase exercise on metabolic outcomes among adults with type 2 diabetes. MATERIALS AND METHODS Extensive literature searching strategies were used to identify published and unpublished intervention studies that measured glycated haemoglobin outcomes. Primary study results were coded. Fixed- and random-effects meta-analytic procedures included moderator analyses. RESULTS Data were synthesised across 10,455 subjects from 103 research reports. The overall mean weighted effect size for two-group comparisons was 0.29 (higher mean for treatment than control). This effect size is consistent with a difference in HbA1c means of 0.45% (e.g. 7.38% for treatment subjects vs 7.83% for control subjects). For single-group studies, the overall mean weighted effect size was 0.32-0.34. Control group subjects experienced no improvement in metabolic control during participation in the studies. Interventions that targeted multiple health behaviours resulted in smaller effect size estimates (0.22) than interventions that focused only on exercise behaviours (0.45). Funded studies reported greater improvements in metabolic controls. Studies with a greater proportion of female subjects reported lower effect sizes. Baseline HbA1c and BMI were unrelated to metabolic outcomes. CONCLUSIONS/INTERPRETATION These findings suggest that self-management interventions that include exercise recommendations improve metabolic control, despite considerable heterogeneity in the magnitude of the intervention effect. Interventions that emphasise exercise may be especially effective in improving metabolic control. Primary research testing interventions in randomised trials to confirm causal relationships would be constructive.
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Affiliation(s)
- V S Conn
- School of Nursing, University of Missouri, Columbia, MO 65211, USA.
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Ayesh AI, Lassesson A, Brown SA, Dunbar ADF, Kaufmann M, Partridge JG, Reichel R, van Lith J. Experimental and simulational study of the operation conditions for a high transmission mass filter. Rev Sci Instrum 2007; 78:053906. [PMID: 17552840 DOI: 10.1063/1.2740121] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/15/2023]
Abstract
The operation conditions of a double pulsed field mass filter were studied using both experiment and simulation. The mass filter consists of two pairs of parallel plates and operates on the time-of-flight principle. The study showed that the ions' beam deflection angle is a critical factor in optimizing the mass filter transmission efficiency. This angle is dependent on the accelerating voltage, ion mass, and horizontal velocity of the ions. The optimum operating conditions for the mass filter were found and used to study the mass distribution of palladium ions produced by a magnetron sputtering source. The study shows that this mass filter is suitable for technological applications because of its high transmission and wide mass range.
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Affiliation(s)
- A I Ayesh
- The MacDiarmid Institute of Advanced Materials and Nanotechnology, University of Canterbury, Christchurch 8020, New Zealand
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Abstract
The pharmacokinetics of the novel cephalosporin cefovecin were investigated in a series of in vivo, ex vivo and in vitro studies following administration to adult cats at 8 mg/kg bodyweight. Bioavailability and pharmacokinetic parameters were determined in a cross-over study after intravenous (i.v.) and subcutaneous (s.c.) injections. [14C]cefovecin was used to evaluate excretion for 21 days after s.c. administration. Protein binding was determined in vitro in feline plasma and ex vivo in transudate from cats surgically implanted with tissue chambers. After s.c. administration, cefovecin was characterized by rapid absorption with mean peak plasma concentrations of 141+/-12 microg/mL being achieved within 2 h of s.c. injection with full bioavailability (99%). The mean elimination half-life was 166+/-18 h. After i.v. administration, volume of distribution was 0.09+/-0.01 L/kg and mean plasma clearance was 0.35+/-0.04 mL/h/kg. Approximately 50% of the administered radiolabelled dose was eliminated over the 21-day postdose period via urinary excretion and up to approximately 25% in faeces. In vitro and ex vivo plasma protein binding ranged from 99.8% to 99.5% over the plasma concentration range 10-100 microg/mL. Ex vivo protein binding in transudate was as low as 90.7%. From 8 h postdose, concentrations of unbound (free) cefovecin in transudate were consistently higher than in plasma, with mean unbound cefovecin concentrations being maintained above 0.06 microg/mL (MIC90 of Pasteurella multocida) in transudate for at least 14 days postdose. The slow elimination and long-lasting free concentrations in extracellular fluid are desirable pharmacokinetic attributes for an antimicrobial with a 14-day dosing interval.
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Affiliation(s)
- M R Stegemann
- Pfizer Animal Health, Veterinary Medicine Research & Development, Pfizer Ltd, Sandwich, Kent, UK.
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Abstract
Circadian clocks influence most aspects of physiology and behavior, so perhaps it is not surprising that circadian oscillators exist in nearly all mammalian cells. These cells remain synchronized to the outside world in hierarchical fashion, with a "master clock" tissue in the suprachiasmatic nucleus of the hypothalamus receiving light input from the retina and then conveying timing information to "slave" clocks in peripheral tissues. Recent research has highlighted both the similarities and differences between central and peripheral clocks and provided new insight into their communication. Above all, however, this parallelism of clockwork has provided a unique opportunity to study at the cellular level a regulatory mechanism that affects complex behaviors.
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Affiliation(s)
- E Kowalska
- University of Zurich, Institute for Pharmacology and Toxicology, 8057 Zurich, Switzerland
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Abstract
We simulate the collision of atomic clusters with a weakly attractive surface using molecular dynamics in a regime between soft landing and fragmentation, where the cluster undergoes large deformation but remains intact. As a function of incident kinetic energy, we find a transition from adhesion to reflection at low kinetic energies. We also identify a second adhesive regime at intermediate kinetic energies, where strong deformation of the cluster leads to an increase in contact area and adhesive energy.
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Affiliation(s)
- A Awasthi
- MacDiarmid Institute for Advanced Materials and Nanotechnology, Industrial Research Ltd., Lower Hutt 5040, New Zealand
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Ilo EC, Orisakwe OE, Ilondu NA, Okwoli N, Brown SA, Elo-Ilo J, Agbasi PU. Effect of chloroquine on the bioavailability of ciprofloxacin in man. J Control Release 2006; 116:e109-10. [PMID: 17718943 DOI: 10.1016/j.jconrel.2006.09.076] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- E C Ilo
- Dept. of Pharmacology, College of Health Sciences, Nnamdi Azikiwe University, Nnewi, Nigeria
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