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Terry G, Pagulayan KF, Muzi M, Mayer C, Murray DR, Schindler AG, Richards TL, McEvoy C, Crabtree A, McNamara C, Means G, Muench P, Powell JR, Mihalik JP, Thomas RG, Raskind MA, Peskind ER, Meabon JS. Increased [ 18F]Fluorodeoxyglucose Uptake in the Left Pallidum in Military Veterans with Blast-Related Mild Traumatic Brain Injury: Potential as an Imaging Biomarker and Mediation with Executive Dysfunction and Cognitive Impairment. J Neurotrauma 2024. [PMID: 38661540 DOI: 10.1089/neu.2023.0429] [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] [Indexed: 04/26/2024] Open
Abstract
Blast-related mild traumatic brain injury (blast-mTBI) can result in a spectrum of persistent symptoms leading to substantial functional impairment and reduced quality of life. Clinical evaluation and discernment from other conditions common to military service can be challenging and subject to patient recall bias and the limitations of available assessment measures. The need for objective biomarkers to facilitate accurate diagnosis, not just for symptom management and rehabilitation but for prognostication and disability compensation purposes is clear. Toward this end, we compared regional brain [18F]fluorodeoxyglucose-positron emission tomography ([18F]FDG-PET) intensity-scaled uptake measurements and motor, neuropsychological, and behavioral assessments in 79 combat Veterans with retrospectively recalled blast-mTBI with 41 control participants having no lifetime history of TBI. Using an agnostic and unbiased approach, we found significantly increased left pallidum [18F]FDG-uptake in Veterans with blast-mTBI versus control participants, p < 0.0001; q = 3.29 × 10-9 [Cohen's d, 1.38, 95% confidence interval (0.96, 1.79)]. The degree of left pallidum [18F]FDG-uptake correlated with the number of self-reported blast-mTBIs, r2 = 0.22; p < 0.0001. Greater [18F]FDG-uptake in the left pallidum provided excellent discrimination between Veterans with blast-mTBI and controls, with a receiver operator characteristic area under the curve of 0.859 (p < 0.0001) and likelihood ratio of 21.19 (threshold:SUVR ≥ 0.895). Deficits in executive function assessed using the Behavior Rating Inventory of Executive Function-Adult Global Executive Composite T-score were identified in Veterans with blast-mTBI compared with controls, p < 0.0001. Regression-based mediation analyses determined that in Veterans with blast-mTBI, increased [18F]FDG-uptake in the left pallidum-mediated executive function impairments, adjusted causal mediation estimate p = 0.021; total effect estimate, p = 0.039. Measures of working and prospective memory (Auditory Consonant Trigrams test and Memory for Intentions Test, respectively) were negatively correlated with left pallidum [18F]FDG-uptake, p < 0.0001, with mTBI as a covariate. Increased left pallidum [18F]FDG-uptake in Veterans with blast-mTBI compared with controls did not covary with dominant handedness or with motor activity assessed using the Unified Parkinson's Disease Rating Scale. Localized increased [18F]FDG-uptake in the left pallidum may reflect a compensatory response to functional deficits following blast-mTBI. Limited imaging resolution does not allow us to distinguish subregions of the pallidum; however, the significant correlation of our data with behavioral but not motor outcomes suggests involvement of the ventral pallidum, which is known to regulate motivation, behavior, and emotions through basal ganglia-thalamo-cortical circuits. Increased [18F]FDG-uptake in the left pallidum in blast-mTBI versus control participants was consistently identified using two different PET scanners, supporting the generalizability of this finding. Although confirmation of our results by single-subject-to-cohort analyses will be required before clinical deployment, this study provides proof of concept that [18F]FDG-PET bears promise as a readily available noninvasive biomarker for blast-mTBI. Further, our findings support a causative relationship between executive dysfunction and increased [18F]FDG-uptake in the left pallidum.
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Affiliation(s)
- Garth Terry
- Mental Illness Research, Education, and Clinical Center (MIRECC), VA Puget Sound Health Care System (VA Puget Sound), Seattle, Washington, USA
- Department of Psychiatry and Behavioral Sciences, University of Washington, Seattle, Washington, USA
- Department of Radiology, University of Washington, Seattle, Washington, USA
| | - Kathleen F Pagulayan
- Department of Rehabilitation Medicine, School of Medicine, University of Washington, Seattle, Washington, USA
| | - Mark Muzi
- Department of Radiology, University of Washington, Seattle, Washington, USA
| | - Cynthia Mayer
- Mental Illness Research, Education, and Clinical Center (MIRECC), VA Puget Sound Health Care System (VA Puget Sound), Seattle, Washington, USA
- Department of Radiology, University of Washington, Seattle, Washington, USA
| | - Daniel R Murray
- Mental Illness Research, Education, and Clinical Center (MIRECC), VA Puget Sound Health Care System (VA Puget Sound), Seattle, Washington, USA
| | - Abigail G Schindler
- Mental Illness Research, Education, and Clinical Center (MIRECC), VA Puget Sound Health Care System (VA Puget Sound), Seattle, Washington, USA
- Department of Psychiatry and Behavioral Sciences, University of Washington, Seattle, Washington, USA
- Geriatric Research, Education, and Clinical Center (GRECC), VA Puget Sound Health Care System (VA Puget Sound), Seattle, Washington, USA
| | - Todd L Richards
- Department of Radiology, University of Washington, Seattle, Washington, USA
| | - Cory McEvoy
- United States Army Special Operations Command, Fort Liberty, North Carolina, USA
| | - Adam Crabtree
- United States Army Special Operations Command, Fort Liberty, North Carolina, USA
| | - Chris McNamara
- United States Army Special Operations Command, Fort Liberty, North Carolina, USA
| | - Gary Means
- United States Army Special Operations Command, Fort Liberty, North Carolina, USA
| | - Peter Muench
- United States Army Special Operations Command, Fort Liberty, North Carolina, USA
| | - Jacob R Powell
- Matthew Gfeller Center, Department of Exercise and Sport Science, The University of North Carolina at Chapel Hill, Stallings-Evans Sports Medicine Center, Chapel Hill, North Carolina, USA
| | - Jason P Mihalik
- Matthew Gfeller Center, Department of Exercise and Sport Science, The University of North Carolina at Chapel Hill, Stallings-Evans Sports Medicine Center, Chapel Hill, North Carolina, USA
| | - Ronald G Thomas
- Division of Biostatistics, Department of Family Medicine & Public Health, University of California San Diego, La Jolla, California, USA
| | - Murray A Raskind
- Mental Illness Research, Education, and Clinical Center (MIRECC), VA Puget Sound Health Care System (VA Puget Sound), Seattle, Washington, USA
- Department of Psychiatry and Behavioral Sciences, University of Washington, Seattle, Washington, USA
| | - Elaine R Peskind
- Mental Illness Research, Education, and Clinical Center (MIRECC), VA Puget Sound Health Care System (VA Puget Sound), Seattle, Washington, USA
- Department of Psychiatry and Behavioral Sciences, University of Washington, Seattle, Washington, USA
| | - James S Meabon
- Mental Illness Research, Education, and Clinical Center (MIRECC), VA Puget Sound Health Care System (VA Puget Sound), Seattle, Washington, USA
- Department of Psychiatry and Behavioral Sciences, University of Washington, Seattle, Washington, USA
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Powell JR, Zong X, Weinstein JM, DeLellis SM, Kane SF, Means GE, Mihalik JP. Mild Traumatic Brain Injury and Career Stage Associate with Visible Perivascular Spaces in Special Operations Forces Soldiers. Ann Biomed Eng 2024:10.1007/s10439-024-03468-2. [PMID: 38396272 DOI: 10.1007/s10439-024-03468-2] [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] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2023] [Accepted: 02/06/2024] [Indexed: 02/25/2024]
Abstract
Mild traumatic brain injury (mTBI) and occupational blast exposure in military Service Members may lead to impaired brain waste clearance which increases neurological disease risk. Perivascular spaces (PVS) are a key part of the glymphatic system which supports brain waste clearance, preferentially during sleep. Visible PVS on clinical magnetic resonance imaging have been previously observed in patients with neurodegenerative diseases and animal neurotrauma models. The purpose of this study was to determine associations between PVS morphological characteristics, military career stage, and mTBI history in Special Operations Forces (SOF) Soldiers. Participants underwent T2-weighed neuroimaging to capture three-dimensional whole brain volumes. Segmentation was performed using a previously validated, multi-scale deep convolutional encoder-decoder neural network. Only PVS clusters within the white matter mask were quantified for analyses. Due to non-normal PVS metric distribution, non-parametric Mann-Whitney U tests were used to determine group differences in PVS outcomes. In total, 223 healthy SOF combat Soldiers (age = 33.1 ± 4.3yrs) were included, 217 reported career stage. Soldiers with mTBI history had greater PVS number (z = 2.51, P = 0.013) and PVS volume (z = 2.42, P = 0.016). In-career SOF combat Soldiers had greater PVS number (z = 2.56, P = 0.01) and PVS volume (z = 2.28, P = 0.02) compared to a baseline cohort. Mild TBI history is associated with increased PVS burden in SOF combat Soldiers that are clinically recovered from mTBI. This may indicate ongoing physiological changes that could lead to impaired waste clearance via the glymphatic system. Future studies should determine if PVS number and volume are meaningful neurobiological outcomes for neurodegenerative disease risk and if clinical interventions such as improving sleep can reduce PVS burden.
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Affiliation(s)
- Jacob R Powell
- Human Movement Science, Department of Health Sciences, School of Medicine, University of North Carolina at Chapel Hill, Chapel Hill, NC, USA
- Matthew Gfeller Center, Department of Exercise and Sport Science, University of North Carolina at Chapel Hill, Chapel Hill, NC, USA
| | - Xiaopeng Zong
- School of Biomedical Engineering, ShanghaiTech University, Pudong, Shanghai, China
| | - Joshua M Weinstein
- Department of Health Policy and Management, Gillings School of Global Public Health, University of North Carolina, Chapel Hill, USA
| | | | - Shawn F Kane
- Matthew Gfeller Center, Department of Exercise and Sport Science, University of North Carolina at Chapel Hill, Chapel Hill, NC, USA
- Department of Family Medicine, University of North Carolina at Chapel Hill, Chapel Hill, NC, USA
| | - Gary E Means
- United States Army Special Operations Command, Fort Liberty, NC, USA
| | - Jason P Mihalik
- Human Movement Science, Department of Health Sciences, School of Medicine, University of North Carolina at Chapel Hill, Chapel Hill, NC, USA.
- Matthew Gfeller Center, Department of Exercise and Sport Science, University of North Carolina at Chapel Hill, Chapel Hill, NC, USA.
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Powell JR, Hopfinger JB, Giovanello KS, Walton SR, DeLellis SM, Kane SF, Means GE, Mihalik JP. Mild traumatic brain injury history is associated with lower brain network resilience in soldiers. Brain Commun 2023; 5:fcad201. [PMID: 37545546 PMCID: PMC10400114 DOI: 10.1093/braincomms/fcad201] [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] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2023] [Revised: 04/12/2023] [Accepted: 07/26/2023] [Indexed: 08/08/2023] Open
Abstract
Special Operations Forces combat soldiers sustain frequent blast and blunt neurotrauma, most often classified as mild traumatic brain injuries. Exposure to repetitive mild traumatic brain injuries is associated with persistent behavioural, cognitive, emotional and neurological symptoms later in life. Identifying neurophysiological changes associated with mild traumatic brain injury exposure, in the absence of present-day symptoms, is necessary for detecting future neurological risk. Advancements in graph theory and functional MRI have offered novel ways to analyse complex whole-brain network connectivity. Our purpose was to determine how mild traumatic brain injury history, lifetime incidence and recency affected whole-brain graph theoretical outcome measures. Healthy male Special Operations Forces combat soldiers (age = 33.2 ± 4.3 years) underwent multimodal neuroimaging at a biomedical research imaging centre using 3T Siemens Prisma or Biograph MRI scanners in this cross-sectional study. Anatomical and functional scans were preprocessed. The blood-oxygen-level-dependent signal was extracted from each functional MRI time series using the Big Brain 300 atlas. Correlations between atlas regions were calculated and Fisher z-transformed to generate subject-level correlation matrices. The Brain Connectivity Toolbox was used to obtain functional network measures for global efficiency (the average inverse shortest path length), local efficiency (the average global efficiency of each node and its neighbours), and assortativity coefficient (the correlation coefficient between the degrees of all nodes on two opposite ends of a link). General linear models were fit to compare mild traumatic brain injury lifetime incidence and recency. Nonparametric ANOVAs were used for tests on non-normally distributed data. Soldiers with a history of mild traumatic brain injury had significantly lower assortativity than those who did not self-report mild traumatic brain injury (t148 = 2.44, P = 0.016). The assortativity coefficient was significantly predicted by continuous mild traumatic brain injury lifetime incidence [F1,144 = 6.51, P = 0.012]. No differences were observed between recency groups, and no global or local efficiency differences were observed between mild traumatic brain injury history and lifetime incidence groups. Brain networks with greater assortativity have more resilient, interconnected hubs, while those with lower assortativity indicate widely distributed, vulnerable hubs. Greater lifetime mild traumatic brain injury incidence predicted lower assortativity in our study sample. Less resilient brain networks may represent a lack of physiological recovery in mild traumatic brain injury patients, who otherwise demonstrate clinical recovery, more vulnerability to future brain injury and increased risk for accelerated age-related neurodegenerative changes. Future longitudinal studies should investigate whether decreased brain network resilience may be a predictor for long-term neurological dysfunction.
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Affiliation(s)
- Jacob R Powell
- Matthew Gfeller Center, Department of Exercise and Sport Science, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, USA
| | - Joseph B Hopfinger
- Department of Psychology and Neuroscience, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, USA
| | - Kelly S Giovanello
- Department of Psychology and Neuroscience, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, USA
| | - Samuel R Walton
- Physical Medicine and Rehabilitation, School of Medicine, Virginia Commonwealth University, Richmond, VA 23284, USA
| | - Stephen M DeLellis
- Fort Liberty Research Institute, The Geneva Foundation, Tacoma, WA 98402, USA
| | - Shawn F Kane
- Matthew Gfeller Center, Department of Exercise and Sport Science, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, USA
- Department of Family Medicine, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, USA
| | - Gary E Means
- United States Army Special Operations Command, Fort Liberty, NC 28303, USA
| | - Jason P Mihalik
- Correspondence to: Jason P. Mihalik Matthew Gfeller Center, Department of Exercise and Sport Science The University of North Carolina at Chapel Hill, 2201 Stallings-Evans Sports Medicine Center Campus Box 8700, Chapel Hill, NC 27599, USA E-mail:
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McEvoy CB, Crabtree A, Powell JR, Meabon JS, Mihalik JP. Cumulative Blast Exposure Estimate Model for Special Operations Forces Combat Soldiers. J Neurotrauma 2023; 40:318-325. [PMID: 35934872 DOI: 10.1089/neu.2022.0075] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023] Open
Abstract
Special Operations Forces (SOF) Service members endure frequent exposures to blast and overpressure mechanisms given their high training tempo. The link between cumulative subconcussive blasts on short- and long-term neurological impairment is largely understudied. Neurodegenerative diseases such as brain dysfunction, cognitive decline, mild cognitive impairment, and dementia may develop with chronic exposures. This hypothesis remains unproven because of lack of ecologically valid occupational blast exposure surveillance among SOF Service members. The purpose of the study was to measure occupational blast exposures in a close quarter battle (CQB) training environment and to use those outcomes to develop a pragmatic cumulative blast exposure (CBE) estimate model. Four blast silhouettes equipped with a field-deployable wireless blast gauge system were positioned in breaching positions during CQB training scenarios. Silhouettes were exposed to flashbangs and three interior breaching charges (single strand roll-up interior charge, 300 grain (gr) explosive cutting tape (ECT), and Jelly charge). Mean blast measures were calculated for each silhouette for flashbangs (n = 93), single strand roll-up interior charge (n = 80), 300 gr ECT (n = 28), and Jelly charge (n = 71). Mean peak blast pressures per detonation are reported as follows: (1) flashbangs (1.97 pounds per square inch [psi]); (2) single strand roll-up interior charge (3.88 psi); (3) 300 gr ECT (2.78 psi); and (4) Jelly charge (1.89 psi). Pragmatic CBE estimates for SOF Service members suggest 36.8 psi, 184 psi, and 2760 psi may represent daily, weekly, and training cycle cumulative pressure exposures. Estimating blast exposures during routine CQB training can be determined from empirical measures taken in CQB environments. Factoring in daily, weekly, training cycle, or even career length may reasonably estimate cumulative occupational training blast exposures for SOF Service members. Future work may permit more granular exposure estimates based on operational blast exposures and those experienced by other military occupational specialties.
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Affiliation(s)
- Cory B McEvoy
- United States Army Special Operations Command, Fort Bragg, North Carolina, USA.,CU Anschutz Center for COMBAT Research, Department of Emergency Medicine, University of Colorado School of Medicine, Aurora, Colorado, USA
| | - Adam Crabtree
- United States Army Special Operations Command, Fort Bragg, North Carolina, USA
| | - Jacob R Powell
- Matthew Gfeller Center, Department of Exercise and Sport Science, Department of Health Sciences, The University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, USA.,Human Movement Science Curriculum, Department of Health Sciences, The University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, USA
| | - James S Meabon
- Mental Illness Research, Education, and Clinical Center (MIRECC), VA Puget Sound Health Care System (VA Puget Sound), Seattle, Washington, USA.,Department of Psychiatry and Behavioral Sciences, University of Washington, Seattle, Washington, USA
| | - Jason P Mihalik
- Matthew Gfeller Center, Department of Exercise and Sport Science, Department of Health Sciences, The University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, USA.,Human Movement Science Curriculum, Department of Health Sciences, The University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, USA
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Mihalik JP, Powell JR, Zong X, Weinstein JM, DeLellis SM, Depenbrock PJ, Means GE, Kane SF. Perivascular Space Morphology Is Affected By Career Exposure In Special Operations Forces Combat Soldiers. Med Sci Sports Exerc 2022. [DOI: 10.1249/01.mss.0000876704.25463.39] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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Lauck BJ, Sinnott AM, Kiefer AW, Padua DA, Powell JR, Sledge HR, Mihalik JP. Association Between Head Impact Biomechanics and Physical Load in College Football. Ann Biomed Eng 2022; 50:1437-1443. [PMID: 35972602 PMCID: PMC9380687 DOI: 10.1007/s10439-022-03042-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2022] [Accepted: 07/29/2022] [Indexed: 11/25/2022]
Abstract
Head impacts and physical exertion are ubiquitous in American football, but the relationship between these factors is poorly understood across a competitive season or even within an individual session. Gameplay characteristics, including player position and session type, may contribute to these relationships but have not been prospectively examined. The current study aimed to determine if an association exists between head impact biomechanics and physical load metrics. We prospectively studied college football players during the 2017–2021 football seasons across representative playing positions (15 offensive and defensive linemen, 11 linebackers and tight ends, and 15 defensive backs, running backs, and receivers). Participants wore halters embedded with Catapult Vector GPS monitoring systems to quantify player load and participant helmets were equipped with the Head Impact Telemetry System to quantify head impact biomechanics and repetitive head impact exposure (RHIE). Generalized linear models and linear regression models were employed to analyze in-session and season-long outcomes, while addressing factors such as player position and session type on our data. Player load was associated with RHIE (p < 0.001). Season-long player load predicted season-long RHIE (R2 = 0.31; p < 0.001). Position group affected in-session player load (p = 0.025). Both player load and RHIE were greater in games than in practices (p < 0.001), and position group did not affect RHIE (p = 0.343). Physical load burden was associated with RHIE within sessions and across an entire season. Session type affected both RHIE and player load, while position group only affected player load. Our data point to tracking physical load burden as a potential proxy for monitoring anticipated RHIE during the season.
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Affiliation(s)
- Bradley J Lauck
- Matthew Gfeller Center, Department of Exercise and Sport Science, The University of North Carolina at Chapel Hill, 2207 Stallings-Evans Sports Medicine Center, Campus, Box 8700, Chapel Hill, NC, 27599-8700, USA
| | - Aaron M Sinnott
- Matthew Gfeller Center, Department of Exercise and Sport Science, The University of North Carolina at Chapel Hill, 2207 Stallings-Evans Sports Medicine Center, Campus, Box 8700, Chapel Hill, NC, 27599-8700, USA
| | - Adam W Kiefer
- Matthew Gfeller Center, Department of Exercise and Sport Science, The University of North Carolina at Chapel Hill, 2207 Stallings-Evans Sports Medicine Center, Campus, Box 8700, Chapel Hill, NC, 27599-8700, USA
- STAR Heel Performance Laboratory, Department of Exercise and Sport Science, The University of North Carolina at Chapel Hill, G406 Fetzer Hall, Chapel Hill, NC, USA
- Human Movement Science, Department of Health Sciences, The University of North Carolina at Chapel Hill, 209 Fetzer Hall, Chapel Hill, NC, USA
| | - Darin A Padua
- MOTION Science Institute, Department of Exercise and Sport Science, The University of North Carolina at Chapel Hill, 032 Fetzer Hall, Chapel Hill, NC, USA
- Human Movement Science, Department of Health Sciences, The University of North Carolina at Chapel Hill, 209 Fetzer Hall, Chapel Hill, NC, USA
| | - Jacob R Powell
- Matthew Gfeller Center, Department of Exercise and Sport Science, The University of North Carolina at Chapel Hill, 2207 Stallings-Evans Sports Medicine Center, Campus, Box 8700, Chapel Hill, NC, 27599-8700, USA
- Human Movement Science, Department of Health Sciences, The University of North Carolina at Chapel Hill, 209 Fetzer Hall, Chapel Hill, NC, USA
| | - Haley R Sledge
- Matthew Gfeller Center, Department of Exercise and Sport Science, The University of North Carolina at Chapel Hill, 2207 Stallings-Evans Sports Medicine Center, Campus, Box 8700, Chapel Hill, NC, 27599-8700, USA
| | - Jason P Mihalik
- Matthew Gfeller Center, Department of Exercise and Sport Science, The University of North Carolina at Chapel Hill, 2207 Stallings-Evans Sports Medicine Center, Campus, Box 8700, Chapel Hill, NC, 27599-8700, USA.
- Human Movement Science, Department of Health Sciences, The University of North Carolina at Chapel Hill, 209 Fetzer Hall, Chapel Hill, NC, USA.
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Castellano AK, Powell JR, Cools MJ, Walton SR, Barnett RR, DeLellis SM, Goldberg RL, Kane SF, Means GE, Zamora CA, Depenbrock PJ, Mihalik JP. Relationship between Anterior Pituitary Volume and IGF-1 Serum Levels in Soldiers with Mild Traumatic Brain Injury History. Med Sci Sports Exerc 2022; 54:1364-1370. [PMID: 35838301 PMCID: PMC9287595 DOI: 10.1249/mss.0000000000002892] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
PURPOSE A high mild traumatic brain injury (mTBI) incidence rate exists in military and sport. Hypopituitarism is an mTBI sequela; however, few studies have examined this phenomenon in those with an mTBI history. This cross-sectional study of Special Operations Forces combat soldiers aimed 1) to relate anterior pituitary gland volumes (actual and normalized) to insulin-like growth factor 1 (IGF-1) concentrations, 2) to examine the effect of mTBI history on anterior pituitary gland volumes (actual and normalized) and IGF-1 concentrations, and 3) to measure the odds of demonstrating lower anterior pituitary gland volumes (actual and normalized) or IGF-1 concentrations if self-reporting mTBI history. METHODS Anterior pituitary gland volumes were manually segmented from T1-weighted 3D brain MRI sequences; IGF-1 serum concentrations were quantified using commercial enzyme-linked immunosorbent assays. Correlations and linear regression were used to determine the association between IGF-1 serum concentration and anterior pituitary gland volume (n = 74). Independent samples t-tests were used to compare outcomes between mTBI groups and logistic regression models were fit to test the odds of demonstrating IGF-1 concentration or anterior pituitary volume less than sample median based on mTBI group (n = 54). RESULTS A significant linear relationship between the subjects' anterior pituitary gland volumes and IGF-1 concentrations (r72 = 0.35, P = 0.002) was observed. Soldiers with mTBI history had lower IGF-1 concentrations (P < 0.001) and lower anterior pituitary gland volumes (P = 0.037) and were at greater odds for IGF-1 serum concentrations less than the sample median (odds ratio = 5.73; 95% confidence interval = 1.77-18.55). CONCLUSIONS Anterior pituitary gland volume was associated with IGF-1 serum concentrations. Mild TBI history may be adversely associated with anterior pituitary gland volumes and IGF-1 concentrations. Longitudinal IGF-1 and anterior pituitary gland monitoring may be indicated in those who report one or more mTBI.
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Affiliation(s)
- Anna K. Castellano
- Matthew Gfeller Center, Department of Exercise and Sport Science, The University of North Carolina at Chapel Hill, Chapel Hill, NC
| | - Jacob R. Powell
- Matthew Gfeller Center, Department of Exercise and Sport Science, The University of North Carolina at Chapel Hill, Chapel Hill, NC
| | - Michael J. Cools
- Matthew Gfeller Center, Department of Exercise and Sport Science, The University of North Carolina at Chapel Hill, Chapel Hill, NC
| | - Samuel R. Walton
- Matthew Gfeller Center, Department of Exercise and Sport Science, The University of North Carolina at Chapel Hill, Chapel Hill, NC
| | - Randaline R. Barnett
- Matthew Gfeller Center, Department of Exercise and Sport Science, The University of North Carolina at Chapel Hill, Chapel Hill, NC
| | | | - Richard L. Goldberg
- Department of Applied Physical Sciences, The University of North Carolina at Chapel Hill, Chapel Hill, NC
| | - Shawn F. Kane
- Department of Family Medicine, The University of North Carolina at Chapel Hill, Chapel Hill, NC
| | - Gary E. Means
- United States Army Special Operations Command, Fort Bragg, NC
| | - Carlos A. Zamora
- Department of Radiology, The University of North Carolina at Chapel Hill, Chapel Hill, NC
| | | | - Jason P. Mihalik
- Matthew Gfeller Center, Department of Exercise and Sport Science, The University of North Carolina at Chapel Hill, Chapel Hill, NC
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Brett BL, Walton S, Meier T, Nencka AS, Powell JR, Giovanello KS, Guskiewicz KK, McCrea M. Head impact exposure, grey matter volume, and moderating effects of estimated IQ and educational attainment in former athletes at midlife. J Neurotrauma 2022; 39:497-507. [PMID: 35044240 PMCID: PMC8978573 DOI: 10.1089/neu.2021.0449] [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] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Repetitive head impact (RHI) exposure has been associated with differences in brain structure among younger active athletes, most often within the hippocampus. Studies of former athletes at early-midlife are limited. We investigated the association between RHI exposure and grey matter structure, as well as moderating factors, among former athletes in early-midlife. Former collegiate football players (N=55; age=37.9+1.5 years) completed magnetic resonance imaging to quantify grey matter morphometry and extensive structured interviews of RHI history (Head Impact Exposure Estimate). Linear regression models tested the association between RHI exposure and GM structures of interest. Interactions were tested for moderators: two estimates of IQ (single word reading and picture vocabulary) and education history. Greater RHI exposure was associated with smaller hippocampal volume, β=-.36, p=.004. Conversely, RHI exposure was not significantly associated with other GM outcomes ps>.05. Education history significantly moderated the association between RHI exposure and hippocampal volume, β=.69, p=.047. Among those with a bachelor's degree, greater RHI exposure was significantly associated with smaller hippocampal volumes, β=-.58, p<.001. For those with graduate/professional degrees, the association between RHI and hippocampal volume was not significant, β=-.33, p=.134. Consistent with studies involving younger, active athletes, smaller hippocampal volumes were selectively associated with greater RHI exposure among former collegiate football players at midlife. This relationship was moderated by higher levels of education. Future longitudinal studies are needed to investigate the course of possible changes that can occur between early-midlife to older ages, as well as the continued protective effect of education and other potential influential factors.
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Affiliation(s)
- Benjamin L Brett
- Medical College of Wisconsin, 5506, Neurosurgery and Neurology, 8701 W Watertown Plank Rd, Milwaukee, Wisconsin, United States, 53226;
| | - Samuel Walton
- University of North Carolina at Chapel Hill College of Arts and Sciences, 169101, Department of Exercise and Sport Science, Chapel Hill, North Carolina, United States;
| | - Timothy Meier
- Medical College of Wisconsin, Neurosurgery, 8701 Watertown Plank Road, Milwaukee, Wisconsin, United States, 53226;
| | - Andrew S Nencka
- Medical College of Wisconsin, Biophysics, Milwaukee, Wisconsin, United States;
| | - Jacob R Powell
- University of North Carolina at Chapel Hill College of Arts and Sciences, 169101, Department of Exercise and Sport Science, Chapel Hill, North Carolina, United States;
| | - Kelly S Giovanello
- University of North Carolina at Chapel Hill, Psychology, Chapel Hill, North Carolina, United States;
| | - Kevin K Guskiewicz
- University of North Carolina, Exercise and Sport Science, CB#8700, Chapel Hill, North Carolina, United States, 27599-8700;
| | - Michael McCrea
- Medical College of Wisconsin, Neurosurgery, Hub for Collaborative Medicine, 8701 Watertown Plank Road, Milwaukee, Wisconsin, United States, 53226;
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Powell JR, Barczak-Scarboro N, Walton SR, Giovanello K, Barnett R, Piazza M, Bailar-Heath MB, Burke R, DeLellis S, Kane S, Lynch J, Means G, Depenbrock P, Mihalik J. Associations Among Subcortical Volumes With Mental Health In Special Operations Forces Combat Service Members. Med Sci Sports Exerc 2021. [DOI: 10.1249/01.mss.0000763096.63297.85] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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10
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Barczak-Scarboro NE, Powell JR, Walton SR, Giovanello KS, Barnett R, Piazza M, Bailar-Heath M, Burke R, DeLellis SM, Kane SF, Lynch JH, Means GE, Depenbrock PJ, Mihalik JP. Cortical Volumes Did Not Associate With Mental Health Symptoms In Special Operations Forces Service Members. Med Sci Sports Exerc 2021. [DOI: 10.1249/01.mss.0000762700.44767.1a] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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11
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Boltz AJ, Powell JR, Robison HJ, Morris SN, Collins CL, Chandran A. Epidemiology of Injuries in National Collegiate Athletic Association Men's Baseball: 2014-2015 Through 2018-2019. J Athl Train 2021; 56:742-749. [PMID: 34280265 DOI: 10.4085/1062-6050-432-20] [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: 11/09/2022]
Abstract
CONTEXT The National Collegiate Athletic Association has supported men's baseball championships since 1947. Since its inception, the number of participating teams and athletes has considerably expanded. BACKGROUND Frequently conducting injury surveillance of collegiate baseball athletes is essential for identifying developing temporal patterns. METHODS Exposure and injury data collected in the National Collegiate Athletic Association Injury Surveillance Program during 2014-2015 through 2018-2019 were analyzed. Injury counts, rates, and proportions were used to describe injury characteristics; injury rate ratios were used to examine differential injury rates. RESULTS The overall injury rate was 3.16 per 1000 athlete-exposures. The preseason injury rate was significantly higher than the regular season injury rate. The most commonly injured body parts were shoulder (16.1%), arm or elbow (16%), and hand or wrist (13.9%). The most reported specific injury was hamstring tear (7.9%). CONCLUSIONS The findings of this study aligned with previous studies-most injuries were due to noncontact and overuse mechanisms, less than one-half of injuries were related to upper extremity body parts, and one-third of all injuries were reported among pitchers.
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Affiliation(s)
- Adrian J Boltz
- Datalys Center for Sports Injury Research and Prevention, Indianapolis, IN
| | - Jacob R Powell
- Matthew Gfeller Sport-Related Traumatic Brain Injury Research Center, Department of Exercise and Sport Science, University of North Carolina at Chapel Hill.,Curriculum in Human Movement Science, Department of Allied Health Sciences, School of Medicine, University of North Carolina at Chapel Hill
| | - Hannah J Robison
- Datalys Center for Sports Injury Research and Prevention, Indianapolis, IN
| | - Sarah N Morris
- Datalys Center for Sports Injury Research and Prevention, Indianapolis, IN
| | - Christy L Collins
- Datalys Center for Sports Injury Research and Prevention, Indianapolis, IN
| | - Avinash Chandran
- Datalys Center for Sports Injury Research and Prevention, Indianapolis, IN
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12
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Chandran A, Morris SN, Powell JR, Boltz AJ, Robison HJ, Collins CL. Epidemiology of Injuries in National Collegiate Athletic Association Men's Football: 2014-2015 Through 2018-2019. J Athl Train 2021; 56:643-650. [PMID: 34280281 DOI: 10.4085/1062-6050-447-20] [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] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
CONTEXT Football is among the most popular collegiate sports in the United States, and participation in National Collegiate Athletic Association (NCAA) football has risen in recent years. BACKGROUND Continued monitoring of football injuries is important for capturing the evolving burden of injuries in NCAA football. The purpose of this study was to describe the epidemiology of football-related injuries among men's NCAA football players during the 2014-2015 through 2018-2019 academic years. METHODS Exposure and injury data collected in the NCAA Injury Surveillance Program were analyzed. Injury counts, rates, and proportions were used to describe injury characteristics, and injury rate ratios were used to examine differential injury rates. RESULTS The overall injury rate was 9.31 per 1000 athlete-exposures. Most injuries occurred during general play (17.5%), blocking (15.8%), and tackling (14.0%). Concussions (7.5%), lateral ligament complex tears (6.9%), and hamstring tears (4.7%) were the most commonly reported injuries. CONCLUSIONS Results of this study were generally consistent with previous findings, though changes over time in rates of commonly reported injuries warrant attention. Continued monitoring of injury incidence is needed to appraise the effectiveness of recently implemented rules changes.
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Affiliation(s)
- Avinash Chandran
- Datalys Center for Sports Injury Research and Prevention, Indianapolis, IN
| | - Sarah N Morris
- Datalys Center for Sports Injury Research and Prevention, Indianapolis, IN
| | - Jacob R Powell
- Matthew Gfeller Sport-Related Traumatic Brain Injury Research Center, Department of Exercise and Sport Science, University of North Carolina at Chapel Hill.,Curriculum in Human Movement Science, Department of Allied Health Sciences, School of Medicine, The University of North Carolina at Chapel Hill
| | - Adrian J Boltz
- Datalys Center for Sports Injury Research and Prevention, Indianapolis, IN
| | - Hannah J Robison
- Datalys Center for Sports Injury Research and Prevention, Indianapolis, IN
| | - Christy L Collins
- Datalys Center for Sports Injury Research and Prevention, Indianapolis, IN
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13
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Powell JR, Boltz AJ, Robison HJ, Morris SN, Collins CL, Chandran A. Epidemiology of Injuries in National Collegiate Athletic Association Men's Wrestling: 2014-2015 Through 2018-2019. J Athl Train 2021; 56:727-733. [PMID: 34280284 DOI: 10.4085/1062-6050-429-20] [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: 11/09/2022]
Abstract
CONTEXT The first men's wrestling National Collegiate Athletic Association (NCAA) Championship was sponsored in 1928; since then, participation has increased. BACKGROUND Continued study of wrestling injury data is essential to identify areas for intervention based on emerging trends. METHODS Exposure and injury data collected in the NCAA Injury Surveillance Program during 2014-2015 through 2018-2019 were analyzed. Injury counts, rates, and proportions were used to describe injury characteristics, and injury rate ratios (IRRs) were used to examine differential injury rates. RESULTS The overall injury rate was 8.82 per 1000 athlete exposures. The competition injury rate was significantly higher than practice injury rate (IRR = 4.11; 95% CI = 3.72, 4.55). The most commonly injured body parts were the knee (21.4%), shoulder (13.4%), and head/face (13.3%), and the most prevalently reported specific injury was concussion. SUMMARY These findings provide the most current update to injury incidence and outcomes in NCAA men's wrestling. We identify notable trends that warrant consideration in future research.
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Affiliation(s)
- Jacob R Powell
- Matthew Gfeller Sport-Related Traumatic Brain Injury Research Center, Department of Exercise and Sport Science, University of North Carolina at Chapel Hill.,Curriculum in Human Movement Science, Department of Allied Health Sciences, School of Medicine, The University of North Carolina at Chapel Hill
| | - Adrian J Boltz
- Datalys Center for Sports Injury Research and Prevention, Indianapolis, IN
| | - Hannah J Robison
- Datalys Center for Sports Injury Research and Prevention, Indianapolis, IN
| | - Sarah N Morris
- Datalys Center for Sports Injury Research and Prevention, Indianapolis, IN
| | - Christy L Collins
- Datalys Center for Sports Injury Research and Prevention, Indianapolis, IN
| | - Avinash Chandran
- Datalys Center for Sports Injury Research and Prevention, Indianapolis, IN
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14
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Powell JR, Boltz AJ, DeCicco JP, Chandran A, DeLellis SM, Healy ML, Kane SF, Lynch JH, Means GE, Mihalik JP. Neurofilament Light Not Associated With Concussion History Or Recency In Special Operations Forces Combat Soldiers. Med Sci Sports Exerc 2020. [DOI: 10.1249/01.mss.0000685928.12249.e6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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15
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Mishriky BM, Okunrintemi V, Jain S, Sewell KA, Powell JR, Cummings DM. Do GLP-1RAs and SGLT-2is reduce cardiovascular events in women with type 2 diabetes? A systematic review and meta-analysis. Diabetes Metab 2020; 47:101160. [PMID: 32439471 DOI: 10.1016/j.diabet.2020.05.002] [Citation(s) in RCA: 4] [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] [Subscribe] [Scholar Register] [Received: 03/10/2020] [Revised: 04/29/2020] [Accepted: 05/06/2020] [Indexed: 12/11/2022]
Abstract
AIMS The risk of cardiovascular disease is often underestimated in women. This leads to a delay in controlling the risk factors for cardiovascular disease and even delays in prescribing medications with cardiovascular benefit. Our aim was to explore if glucagon-like peptide-1 receptor agonist (GLP-1RA) or sodium-glucose cotransporter-2 inhibitor (SGLT-2i) medications would reduce cardiovascular events in women with type 2 diabetes when atherosclerotic cardiovascular disease (ASCVD) predominates. MATERIALS AND METHODS We searched for randomized trials comparing GLP-1RA or SGLT-2i to placebo in people with type 2 diabetes and had a primary outcome exploring major adverse cardiovascular events (MACE). Data concerning women were then extracted. A sensitivity and subgroup analyses were performed according to the class of diabetes medication. RESULTS A total of 9 trials (GLP-1RA in 6 trials and SGLT-2i in 3) were included. Of the 84,258 participants enrolled, 30,784 (37%) participants were women. Pooled results showed a statistically significant lower incidence of MACE favouring diabetes medications (GLP-1RA or SGLT-2i) compared to placebo (RR [95%CI]=0.87 [0.80, 0.94]). On restricting the analysis to GLP-1RA then to SGLT-2i, results remained significant with GLP-1RA but not SGLT-2i. CONCLUSIONS In women with type 2 diabetes who either have increased cardiovascular risk or established cardiovascular disease and ASCVD predominates, GLP-1RA significantly reduce the incidence of MACE while SGLT-2i result in a non-significant reduction. SGLT-2i may have comparable effect when examined in more studies. GLP-1RA and SGLT-2i should be considered without delay in women with type 2 diabetes and increased risk for cardiovascular disease.
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Affiliation(s)
- B M Mishriky
- Department of Internal Medicine, East Carolina University, 521 Moye Blvd (2(nd) floor), Greenville NC 27834, United States.
| | - V Okunrintemi
- Department of Internal Medicine, East Carolina University, 521 Moye Blvd (2(nd) floor), Greenville NC 27834, United States.
| | - S Jain
- Department of Internal Medicine, East Carolina University, 521 Moye Blvd (2(nd) floor), Greenville NC 27834, United States.
| | - K A Sewell
- Laupus Health Sciences Library, East Carolina University, Greenville, NC, United States.
| | - J R Powell
- Department of Internal Medicine, East Carolina University, 521 Moye Blvd (2(nd) floor), Greenville NC 27834, United States.
| | - D M Cummings
- Department of Family Medicine, East Carolina University, Greenville, NC, United States.
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16
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Powell JR, Murray L, Burnet NG, Fernandez S, Lingard Z, McParland L, O'Hara DJ, Whitfield GA, Short SC. Patient Involvement in the Design of a Randomised Trial of Proton Beam Radiotherapy Versus Standard Radiotherapy for Good Prognosis Glioma. Clin Oncol (R Coll Radiol) 2019; 32:89-92. [PMID: 31607613 DOI: 10.1016/j.clon.2019.09.049] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/13/2019] [Revised: 08/02/2019] [Accepted: 08/14/2019] [Indexed: 11/12/2022]
Affiliation(s)
- J R Powell
- Department of Oncology, Velindre University NHS Trust, Cardiff, UK.
| | - L Murray
- St James's Hospital and Leeds Institute of Medical Research, University of Leeds, Leeds, UK
| | - N G Burnet
- Division of Cancer Sciences, Manchester Cancer Research Centre, University of Manchester, Manchester, UK; Department of Oncology, The Christie NHS Foundation Trust, Manchester, UK
| | - S Fernandez
- Clinical Trials Research Unit, Leeds Institute of Clinical Trials Research, University of Leeds, Leeds, UK
| | - Z Lingard
- Division of Cancer Sciences, Manchester Cancer Research Centre, University of Manchester, Manchester, UK
| | - L McParland
- Department of Oncology, Leeds Teaching Hospitals NHS Trust, Leeds, UK
| | - D J O'Hara
- Clinical and Health Psychology, Leeds Teaching Hospitals NHS Trust, Leeds, UK
| | - G A Whitfield
- Division of Cancer Sciences, Manchester Cancer Research Centre, University of Manchester, Manchester, UK; Department of Oncology, The Christie NHS Foundation Trust, Manchester, UK
| | - S C Short
- St James's Hospital and Leeds Institute of Medical Research, University of Leeds, Leeds, UK
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17
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Gloria-Soria A, Armstrong PM, Powell JR, Turner PE. Infection rate of Aedes aegypti mosquitoes with dengue virus depends on the interaction between temperature and mosquito genotype. Proc Biol Sci 2018; 284:rspb.2017.1506. [PMID: 28978730 DOI: 10.1098/rspb.2017.1506] [Citation(s) in RCA: 32] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2017] [Accepted: 09/04/2017] [Indexed: 11/12/2022] Open
Abstract
Dengue fever is the most prevalent arthropod-transmitted viral disease worldwide, with endemic transmission restricted to tropical and subtropical regions of different temperature profiles. Temperature is epidemiologically relevant because it affects dengue infection rates in Aedes aegypti mosquitoes, the major vector of the dengue virus (DENV). Aedes aegypti populations are also known to vary in competence for different DENV genotypes. We assessed the effects of mosquito and virus genotype on DENV infection in the context of temperature by challenging Ae. aegypti from two locations in Vietnam, which differ in temperature regimes, with two isolates of DENV-2 collected from the same two localities, followed by incubation at 25, 27 or 32°C for 10 days. Genotyping of the mosquito populations and virus isolates confirmed that each group was genetically distinct. Extrinsic incubation temperature (EIT) and DENV-2 genotype had a direct effect on the infection rate, consistent with previous studies. However, our results show that the EIT impacts the infection rate differently in each mosquito population, indicating a genotype by environment interaction. These results suggest that the magnitude of DENV epidemics may not only depend on the virus and mosquito genotypes present, but also on how they interact with local temperature. This information should be considered when estimating vector competence of local and introduced mosquito populations during disease risk evaluation.
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Affiliation(s)
- A Gloria-Soria
- Department of Ecology and Evolutionary Biology, Yale University, 165 Prospect St. PO Box 208106, New Haven, CT 06520-8106, USA
| | - P M Armstrong
- The Connecticut Agricultural Experiment Station, 123 Huntington St. PO Box 1106, New Haven, CT 06504, USA
| | - J R Powell
- Department of Ecology and Evolutionary Biology, Yale University, 165 Prospect St. PO Box 208106, New Haven, CT 06520-8106, USA
| | - P E Turner
- Department of Ecology and Evolutionary Biology, Yale University, 165 Prospect St. PO Box 208106, New Haven, CT 06520-8106, USA.,Program in Microbiology, Yale School of Medicine, New Haven, CT 06520, USA
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18
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Oliver JJ, Connor RE, Powell JR, Oliver JM, Long B. Delayed Migration and Perforation of the Jugular Vein by a Peripherally Inserted Central Catheter. Clin Pract Cases Emerg Med 2017; 1:384-386. [PMID: 29849343 PMCID: PMC5965221 DOI: 10.5811/cpcem.2017.9.35829] [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] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2017] [Revised: 09/07/2017] [Accepted: 09/22/2017] [Indexed: 11/23/2022] Open
Abstract
We report a case of peripherally inserted central catheter (PICC) migration and perforation of the left internal jugular vein in a home health setting in an 80-year-old female. A left sided PICC was placed for treatment of diverticulitis following hospital discharge. She complained of sudden onset left sided neck pain immediately after starting an infusion of vancomycin. In the emergency department the injury was identified by portable chest radiograph and computed tomography of her neck. Following removal of the line, she had an uneventful course. Emergency physicians should be aware of this possible PICC line complication.
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Affiliation(s)
- Joshua J Oliver
- San Antonio Uniformed Services Health Education, Department of Emergency Medicine, Fort Sam Houston, Texas
| | - R Erik Connor
- San Antonio Uniformed Services Health Education, Department of Emergency Medicine, Fort Sam Houston, Texas
| | - Jacob R Powell
- San Antonio Uniformed Services Health Education, Department of Emergency Medicine, Fort Sam Houston, Texas
| | - Jessica M Oliver
- Baptist Health System at Mission Trails, Intensive Care Unit, Department of Critical Care Nursing, San Antonio, Texas
| | - Brit Long
- San Antonio Uniformed Services Health Education, Department of Emergency Medicine, Fort Sam Houston, Texas
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19
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Darwich AS, Ogungbenro K, Vinks AA, Powell JR, Reny JL, Marsousi N, Daali Y, Fairman D, Cook J, Lesko LJ, McCune JS, Knibbe CAJ, de Wildt SN, Leeder JS, Neely M, Zuppa AF, Vicini P, Aarons L, Johnson TN, Boiani J, Rostami-Hodjegan A. Why Has Model-Informed Precision Dosing Not Yet Become Common Clinical Reality? Lessons From the Past and a Roadmap for the Future. Clin Pharmacol Ther 2017; 101:646-656. [DOI: 10.1002/cpt.659] [Citation(s) in RCA: 121] [Impact Index Per Article: 17.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2017] [Revised: 02/07/2017] [Accepted: 02/07/2017] [Indexed: 12/17/2022]
Affiliation(s)
- A S Darwich
- Centre for Applied Pharmacokinetic Research, Division of Pharmacy and Optometry; University of Manchester; Manchester UK
| | - K Ogungbenro
- Centre for Applied Pharmacokinetic Research, Division of Pharmacy and Optometry; University of Manchester; Manchester UK
| | - A A Vinks
- Cincinnati Children's Hospital Medical Center; Cincinnati Ohio USA
- Department of Pediatrics; University of Cincinnati School of medicine; Cincinnati Ohio USA
| | - J R Powell
- Eshelman School of Pharmacy; University of North Carolina; Chapel Hill North Carolina USA
| | - J-L Reny
- Geneva Platelet Group, School of Medicine; University of Geneva; Geneva Switzerland
- Department of Internal Medicine, Rehabilitation and Geriatrics; Geneva University Hospitals; Geneva Switzerland
| | - N Marsousi
- Clinical Pharmacology and Toxicology; Geneva University Hospitals; Geneva Switzerland
| | - Y Daali
- Geneva Platelet Group, School of Medicine; University of Geneva; Geneva Switzerland
- Clinical Pharmacology and Toxicology; Geneva University Hospitals; Geneva Switzerland
| | - D Fairman
- Clinical Pharmacology Modeling and Simulation, GSK Stevenage; UK
| | - J Cook
- Clinical Pharmacology, Pfizer Inc; Groton Connecticut USA
| | - L J Lesko
- Department of Pharmaceutics, Center for Pharmacometrics and Systems Pharmacology; University of Florida at Lake Nona (Orlando); Orlando Florida USA
| | - J S McCune
- University of Washington Department of Pharmaceutics and Fred Hitchinson Cancer Research Center Clinical Research Division; Seattle Washington USA
| | - C A J Knibbe
- Department of Clinical Pharmacy, St. Antonius Hospital, Nieuwegein, the Netherlands and Division of Pharmacology, Leiden Academic Centre for Drug Research; Leiden University; the Netherlands
| | - S N de Wildt
- Department of Pharmacology and Toxicology; Radboud University; Nijmegen the Netherlands
- Intensive Care and Department of Pediatric Surgery, Erasmus MC Sophia Children's Hospital; Rotterdam the Netherlands
| | - J S Leeder
- Division of Pediatric Pharmacology and Medical Toxicology, Department of Pediatrics, Children's Mercy Hospitals and Clinics; Kansas City Missouri USA
- Department of Pharmacology; University of Missouri-Kansas City; Kansas City Missouri USA
| | - M Neely
- University of Southern California and the Children's Hospital of Los Angeles; Los Angeles California USA
| | - A F Zuppa
- Children's Hospital of Philadelphia; Philadelphia Pennsylvania USA
| | - P Vicini
- Clinical Pharmacology, Pharmacometrics and DMPK, MedImmune; Cambridge UK
| | - L Aarons
- Centre for Applied Pharmacokinetic Research, Division of Pharmacy and Optometry; University of Manchester; Manchester UK
| | - T N Johnson
- Certara, Blades Enterprise Centre; Sheffield UK
| | - J Boiani
- Epstein Becker & Green; Washington DC USA
| | - A Rostami-Hodjegan
- Centre for Applied Pharmacokinetic Research, Division of Pharmacy and Optometry; University of Manchester; Manchester UK
- Epstein Becker & Green; Washington DC USA
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20
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Han K, Claret L, Piao Y, Hegde P, Joshi A, Powell JR, Jin J, Bruno R. Simulations to Predict Clinical Trial Outcome of Bevacizumab Plus Chemotherapy vs. Chemotherapy Alone in Patients With First-Line Gastric Cancer and Elevated Plasma VEGF-A. CPT Pharmacometrics Syst Pharmacol 2016; 5:352-8. [PMID: 27404946 PMCID: PMC4961078 DOI: 10.1002/psp4.12064] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 09/18/2015] [Accepted: 01/26/2016] [Indexed: 12/31/2022]
Abstract
To simulate clinical trials to assess overall survival (OS) benefit of bevacizumab in combination with chemotherapy in selected patients with gastric cancer (GC), a modeling framework linking OS with tumor growth inhibition (TGI) metrics and baseline patient characteristics was developed. Various TGI metrics were estimated using TGI models and data from two phase III studies comparing bevacizumab plus chemotherapy vs. chemotherapy as first‐line therapy in 976 GC patients. Time‐to‐tumor‐growth (TTG) was the best TGI metric to predict OS. TTG, Eastern Cooperative Oncology Group (ECOG) score, albumin level, and Asian ethnicity were significant covariates in the final OS model. The model correctly predicted a decreased hazard ratio favorable to bevacizumab in patients with high baseline plasma VEGF‐A above the median of 113.4 ng/L. Based on trial simulations, in trials enrolling patients with elevated baseline plasma VEGF‐A (500 patients per arm), the expected hazard ratio was 0.82 (95% prediction interval: 0.70–0.95), independent of ethnicity.
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Affiliation(s)
- K Han
- Genentech Inc, Clinical Pharmacology, South San Francisco, California, USA
| | - L Claret
- Pharsight Consulting Services, Pharsight, a Certara Company, Marseille, France
| | - Y Piao
- Roche Product Development in Asia Pacific, Shanghai, China
| | - P Hegde
- Genentech Inc, Biomarker, South San Francisco, California, USA
| | - A Joshi
- Genentech Inc, Clinical Pharmacology, South San Francisco, California, USA
| | - J R Powell
- Pharmaceutical Research and Early Development (pRED), Roche, Beijing, China
| | - J Jin
- Genentech Inc, Clinical Pharmacology, South San Francisco, California, USA
| | - R Bruno
- Pharsight Consulting Services, Pharsight, a Certara Company, Marseille, France
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21
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Gloria-Soria A, Kellner DA, Brown JE, Gonzalez-Acosta C, Kamgang B, Lutwama J, Powell JR. Temporal genetic stability of Stegomyia aegypti (= Aedes aegypti) populations. Med Vet Entomol 2016; 30:235-240. [PMID: 26744174 PMCID: PMC4856540 DOI: 10.1111/mve.12153] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/02/2015] [Revised: 05/12/2015] [Accepted: 07/23/2015] [Indexed: 06/05/2023]
Abstract
The mosquito Stegomyia aegypti (= Aedes aegypti) (Diptera: Culicidae) is the primary vector of viruses that cause yellow fever, dengue and Chikungunya fever. In the absence of effective vaccines, the reduction of these diseases relies on vector control strategies. The success of these strategies is tightly linked to the population dynamics of target populations. In the present study, 14 collections from St. aegypti populations separated by periods of 1-13 years were analysed to determine their temporal genetic stability. Although temporal structure is discernible in most populations, the degree of temporal differentiation is dependent on the population and does not obscure the geographic structure of the various populations. The results suggest that performing detailed studies in the years prior to and after population reduction- or modification-based control interventions at each target field site may be useful in assessing the probability of success.
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Affiliation(s)
- A Gloria-Soria
- Department of Ecology and Evolutionary Biology, Yale University, New Haven, CT, U.S.A
| | - D A Kellner
- Department of Ecology and Evolutionary Biology, Yale University, New Haven, CT, U.S.A
| | - J E Brown
- Department of Ecology and Evolutionary Biology, Yale University, New Haven, CT, U.S.A
| | - C Gonzalez-Acosta
- Programa de Enfermedades Transmitidas por Vector, Centro Nacional de Programas Preventivos y Control de Enfermedades (CENAPRECE), México, Distrito Federal, México
| | - B Kamgang
- Virology Department, Institut Pasteur de Bangui, Bangui, Central African Republic
| | - J Lutwama
- Department of Arbovirology, Uganda Virus Research Institute, Entebbe, Uganda
| | - J R Powell
- Department of Ecology and Evolutionary Biology, Yale University, New Haven, CT, U.S.A
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22
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Hortal S, Powell JR, Plett JM, Simonin A, Anderson IC. Intraspecific competition between ectomycorrhizal Pisolithus microcarpus isolates impacts plant and fungal performance under elevated CO2 and temperature. FEMS Microbiol Ecol 2016; 92:fiw113. [PMID: 27222224 DOI: 10.1093/femsec/fiw113] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [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: 05/18/2016] [Indexed: 11/14/2022] Open
Abstract
Root systems are simultaneously colonized by multiple individuals of mycorrhizal fungi. Intraspecific competitive interactions between fungal isolates are likely to affect both fungal and plant performance and be influenced by abiotic factors. Here, we assessed the impact of intraspecific competition between three Pisolithus microcarpus isolates on the establishment of, and benefit derived from, symbioses with Eucalyptus grandis seedlings. We investigated the outcomes of competition under ambient and elevated temperature and CO2 concentration ([CO2]) in a factorial design. We observed a reduction in mycelium growth, mycorrhiza formation and seedling mass when two P. microcarpus isolates were co-inoculated on a single E. grandis seedling. Isolates invested more in mycelium than in mycorrhizas in the presence of a competitor. All isolates responded negatively to elevated [CO2] and positively to elevated temperature, which led to no changes on the outcomes of the interactions with changing conditions. However, the presence of a competitor hindered the positive response of P. microcarpus isolates to warming, which resulted in larger negative effects of competition under elevated temperature than under ambient conditions. Our study highlights the need to consider how competition affects individual fungal responses as well as plant performance when trying to predict the impacts of climate change.
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Affiliation(s)
- S Hortal
- Hawkesbury Institute for the Environment, Western Sydney University, Hawkesbury Campus, Locked Bag 1797, Penrith NSW 2751, Australia
| | - J R Powell
- Hawkesbury Institute for the Environment, Western Sydney University, Hawkesbury Campus, Locked Bag 1797, Penrith NSW 2751, Australia
| | - J M Plett
- Hawkesbury Institute for the Environment, Western Sydney University, Hawkesbury Campus, Locked Bag 1797, Penrith NSW 2751, Australia
| | - A Simonin
- Hawkesbury Institute for the Environment, Western Sydney University, Hawkesbury Campus, Locked Bag 1797, Penrith NSW 2751, Australia
| | - I C Anderson
- Hawkesbury Institute for the Environment, Western Sydney University, Hawkesbury Campus, Locked Bag 1797, Penrith NSW 2751, Australia
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Sayson SL, Gloria-Soria A, Powell JR, Edillo FE. Seasonal Genetic Changes of Aedes aegypti (Diptera: Culicidae) Populations in Selected Sites of Cebu City, Philippines. J Med Entomol 2015; 52:638-46. [PMID: 26335470 PMCID: PMC4592349 DOI: 10.1093/jme/tjv056] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/27/2014] [Accepted: 04/21/2015] [Indexed: 05/26/2023]
Abstract
Aedes aegypti (L.) is the primary vector of dengue virus in the Philippines, where dengue is endemic. We examined the genetic changes of Ae. aegypti collected from three selected sites in Cebu city, Philippines, during the relatively wet (2011-2012) and dry seasons (2012 and 2013). A total of 493 Ae. aegypti adults, reared in the laboratory from field-collected larvae, were analyzed using 11 microsatellite loci. Seasonal variation was observed in allele frequencies and allelic richness. Average genetic differentiation (DEST=0.018; FST=0.029) in both dry seasons was higher, due to reduced Ne, than in the wet season (DEST=0.006; FST=0.009). Thus, average gene flow was higher in the wet season than in the dry seasons. However, the overall FST estimate (0.02) inclusive of the two seasons showed little genetic differentiation as supported by Bayesian clustering analysis. Results suggest that during the dry season the intense selection that causes a dramatic reduction of population size favors heterozygotes, leading to small pockets of mosquitoes (refuges) that exhibit random genetic differentiation. During the wet season, the genetic composition of the population is reconstituted by the expansion of the refuges that survived the preceding dry season. Source reduction of mosquitoes during the nonepidemic dry season is thus recommended to prevent dengue re-emergence in the subsequent wet season.
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Affiliation(s)
- S L Sayson
- Department of Biology, University of San Carlos - Talamban Campus, Talamban, Cebu City, Philippines 6000.
| | - A Gloria-Soria
- Department of Ecology and Evolutionary Biology, Yale University, New Haven, CT 06511
| | - J R Powell
- Department of Ecology and Evolutionary Biology, Yale University, New Haven, CT 06511
| | - F E Edillo
- Department of Biology, University of San Carlos - Talamban Campus, Talamban, Cebu City, Philippines 6000
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Affiliation(s)
- T Caruso
- Freie Universität Berlin, Institut für Biologie, Dahlem Center of Plant Sciences, Altensteinstrasse 6, 14195 Berlin, Germany.
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Powell JR, Mucci B. An audit of breast imaging scoring by radiologists, in cases of proven malignancy. Breast Cancer Res 2011. [PMCID: PMC3238255 DOI: 10.1186/bcr2970] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
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Abstract
Drug development and regulatory decisions are driven by information that is compiled primarily from clinical trials and other supportive experiments, but also through clinical experience in the post-market period. The wisdom of these decisions determines the efficiency of drug development, the decision to approve the drug, and the resultant drug product quality including guidance on how to use the product known as the label. Although the decisions are usually simple in nature (e.g., trial design and project progression at the company, product and labeling approval at the Food and Drug Administration (FDA)), the information informing the decision is complex and diverse.
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Affiliation(s)
- J R Powell
- Office of Translational Sciences, Center for Drug Evaluation and Research, FDA, Silver Spring, Maryland, USA.
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Bhattaram VA, Bonapace C, Chilukuri DM, Duan JZ, Garnett C, Gobburu JVS, Jang SH, Kenna L, Lesko LJ, Madabushi R, Men Y, Powell JR, Qiu W, Ramchandani RP, Tornoe CW, Wang Y, Zheng JJ. Impact of Pharmacometric Reviews on New Drug Approval and Labeling Decisions—a Survey of 31 New Drug Applications Submitted Between 2005 and 2006. Clin Pharmacol Ther 2007; 81:213-21. [PMID: 17259946 DOI: 10.1038/sj.clpt.6100051] [Citation(s) in RCA: 101] [Impact Index Per Article: 5.9] [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: 11/08/2022]
Abstract
Exploratory analyses of data pertaining to pharmacokinetic, pharmacodynamic, and disease progression are often referred to as the pharmacometrics (PM) analyses. The objective of the current report is to assess the role of PM, at the Food and Drug Administration (FDA), in drug approval and labeling decisions. We surveyed the impact of PM analyses on New Drug Applications (NDAs) reviewed over 15 months in 2005-2006. The survey focused on both the approval and labeling decisions through four perspectives: clinical pharmacology primary reviewer, their team leader, the clinical team member, and the PM reviewer. A total of 31 NDAs included a PM review component. Review of NDAs involved independent quantitative evaluation by FDA pharmacometricians. PM analyses were ranked as important in regulatory decision making in over 85% of the 31 NDAs. Case studies are presented to demonstrate the applications of PM analysis.
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Affiliation(s)
- V A Bhattaram
- Office of Clinical Pharmacology, Office of Translational Sciences, Center for Drug Evaluation and Research, Food and Drug Administration, Silver Spring, Maryland, USA
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28
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Abstract
Male hybrids between Anopheles gambiae and An. arabiensis suffer from hybrid sterility, and inviability effects are sometimes present as well. We examined the genetic basis of these reproductive barriers between the two species, using 21 microsatellite markers. Generally, recessive inviability effects were found on the X chromosome of gambiae that are incompatible with at least one factor on each arabiensis autosome. Inviability is complete when the gambiae and arabiensis inviability factors are hemi- or homozygous. Using a QTL mapping approach, regions that contribute to male hybrid sterility were also identified. The X chromosome has a disproportionately large effect on male hybrid sterility. Additionally, several moderate-to-large autosomal QTL were found in both species. The effect of these autosomal QTL is contingent upon the presence of an X chromosome from the other species. Substantial regions of the autosomes do not contribute markedly to male hybrid sterility. Finally, no evidence for epistatic interactions between conspecific sterility loci was found.
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Affiliation(s)
- M Slotman
- Department of Ecology and Evolutionary Biology, Yale University, New Haven, Connecticut 06511-7444, USA.
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29
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Schmolz M, Hurst TL, Bailey DM, Powell JR, Forsey RJ, Thompson JM, Williams C, Pawelec G. Validation of a new highly standardised, lab-independent whole-blood leukocyte function assay for clinical trials (ILCS). Exp Gerontol 2004; 39:667-71. [PMID: 15050304 DOI: 10.1016/j.exger.2003.09.029] [Citation(s) in RCA: 8] [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] [Received: 08/01/2003] [Revised: 08/19/2003] [Accepted: 09/10/2003] [Indexed: 10/26/2022]
Abstract
Physical stress induced in healthy volunteers by the Loughborough intermittent shuttle test (LIST) was used to validate a newly developed whole-blood cell culture system (Instant leukocyte culture system (ILCS). Exercise induced immune modulation was investigated through measurement of cytokine levels after activating leukocytes in peripheral blood ex vivo using the physiologic stimulant lipopolysaccharide (LPS). LPS induced production of three different cytokines, interferon gamma (IFNgamma), interleukin-6 (IL-6), and interleukin-10 (IL-10). IFNgamma levels were significantly decreased (P = 0.02 and P = 0.001 ) and IL-10 levels significantly increased (P= 0.04 and 0.03) after exercise. LPS induced IL-6 production was only marginally further increased by exercise. In conclusion, the ILCS system provided a reliable ex vivo method, showing common as well as subject specific features in the time course of the immune modulation caused by the LIST protocol. This system will be useful for studies of the elderly, where cytokine standardisation is notoriously difficult.
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Affiliation(s)
- M Schmolz
- Experimental and Diagnostic Immunology (EDI) GmbH, Markwiesenstr. 55, D-72770 Reutlingen, Germany
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30
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Thompson D, Bailey DM, Hill J, Hurst T, Powell JR, Williams C. Prolonged vitamin C supplementation and recovery from eccentric exercise. Eur J Appl Physiol 2004; 92:133-8. [PMID: 15024666 DOI: 10.1007/s00421-004-1064-y] [Citation(s) in RCA: 42] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 01/21/2004] [Indexed: 12/15/2022]
Abstract
We have previously shown that vitamin C supplementation affects recovery from an unaccustomed bout of demanding exercise, with the most pronounced effect being that on plasma interleukin-6 concentration. However, because of the proposed role of interleukin-6 in the regulation of metabolism, it was unclear whether this represented a reduced response to muscle damage or some form of interaction with the metabolic demands of the activity. Therefore, the aim of the present study was to investigate the effect of the same form of supplementation on a bout of exercise that initiated similar muscle damage but had a low metabolic cost. Fourteen male subjects were allocated to either a placebo (P) or a vitamin C (VC) group. The VC group consumed 200 mg of ascorbic acid twice a day for 14 days prior to a bout of exercise and for the 3 days after exercise. The P group consumed identical capsules that contained 200 mg lactose. Subjects performed 30 min of downhill running at a gradient of -18% and recovery was monitored for up to 3 days after exercise. Plasma VC concentrations in the VC group increased following supplementation. Nevertheless, downhill running provoked a similar increase in circulating markers of muscle damage (creatine kinase activity and myoglobin concentration) and muscle soreness in P and VC groups. Similarly, although downhill running increased plasma interleukin-6, there was no effect from VC supplementation. These results suggest that vitamin C supplementation does not affect interleukin-6 concentrations following eccentric exercise that has a low metabolic component.
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Affiliation(s)
- D Thompson
- Department of Sport and Exercise Science, University of Bath, Bath, BA2 7AY, UK.
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Abstract
Restrictions to gene flow among molecular forms of the mosquito Anopheles gambiae sensu stricto reveal an ongoing speciation process affecting the epidemiology of malaria in sub-Saharan Africa.
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Affiliation(s)
- A della Torre
- Parasitology Unit, Department of Public Health, University of Rome "La Sapienza," P.le Aldo Moro 5, 00185 Rome, Italy.
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Thompson D, Williams C, McGregor SJ, Nicholas CW, McArdle F, Jackson MJ, Powell JR. Prolonged vitamin C supplementation and recovery from demanding exercise. Int J Sport Nutr Exerc Metab 2001; 11:466-81. [PMID: 11915781 DOI: 10.1123/ijsnem.11.4.466] [Citation(s) in RCA: 87] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
The aim of the present study was to investigate whether 2 weeks of vitamin C supplementation affects recovery from an unaccustomed bout of exercise. Sixteen male subjects were allocated to either a placebo (P; n = 8) or vitamin C group (VC; n = 8). The VC group consumed 200 mg of ascorbic acid twice a day, whereas the P group consumed identical capsules containing 200 mg of lactose. Subjects performed a prolonged (90-min) intermittent shuttle-running test 14 days after supplementation began. Post-exercise serum creatine kinase activities and myoglobin concentrations were unaffected by supplementation. However, vitamin C supplementation had modest beneficial effects on muscle soreness, muscle function, and plasma concentrations of malondialdehyde. Furthermore, although plasma interleukin-6 increased immediately after exercise in both groups, values in the VC group were lower than in the P group 2 hours after exercise (p < .05). These results suggest that prolonged vitamin C supplementation has some modest beneficial effects on recovery from unaccustomed exercise.
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Affiliation(s)
- D Thompson
- Department of Sport and Exercise Science at the University of Taths, UK
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Thies F, Miles EA, Nebe-von-Caron G, Powell JR, Hurst TL, Newsholme EA, Calder PC. Influence of dietary supplementation with long-chain n-3 or n-6 polyunsaturated fatty acids on blood inflammatory cell populations and functions and on plasma soluble adhesion molecules in healthy adults. Lipids 2001; 36:1183-93. [PMID: 11795850 DOI: 10.1007/s11745-001-0831-4] [Citation(s) in RCA: 206] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
Abstract
Greatly increasing the amounts of flaxseed oil [rich in alpha-linolenic acid (ALNA)] or fish oil (FO); [rich in eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA)] in the diet can decrease inflammatory cell functions and so might impair host defense. The objective of this study was to determine the effect of dietary supplementation with moderate levels of ALNA, gamma-linolenic acid (GLA), arachidonic acid (ARA), DHA, or FO on inflammatory cell numbers and functions and on circulating levels of soluble adhesion molecules. Healthy subjects aged 55 to 75 yr consumed nine capsules per day for 12 wk. The capsules contained placebo oil (an 80:20 mix of palm and sunflowerseed oils) or blends of placebo oil with oils rich in ALNA, GLA, ARA, or DHA or FO. Subjects in these groups consumed 2 g ALNA; approximately 700 mg GLA, ARA, or DHA; or 1 g EPA plus DHA (720 mg EPA + 280 mg DHA) daily from the capsules. Total fat intake from the capsules was 4 g per day. None of the treatments affected inflammatory cell numbers in the bloodstream; neutrophil and monocyte phagocytosis or respiratory burst in response to E. coli; production of tumor necrosis factor-alpha, interleukin-1beta, and interleukin-6 in response to bacterial lipopolysaccharide; or plasma concentrations of soluble intercellular adhesion molecule-1. In contrast, the ALNA and FO treatments decreased the plasma concentrations of soluble vascular cell adhesion molecule-1 (16 and 28% decrease, respectively) and soluble E-selectin (23 and 17% decrease, respectively). It is concluded that, in contrast to previous reports using higher amounts of these fatty acids, a moderate increase in consumption of long-chain n-6 or n-3 polyunsaturated fatty acids does not significantly affect inflammatory cell numbers or neutrophil and monocyte responses in humans and so would not be expected to cause immune impairment. Furthermore, we conclude that moderate levels of ALNA and FO, which could be incorporated into the diet, can decrease some markers of endothelial activation and that this mechanism of action may contribute to the reported health benefits of n-3 fatty acids.
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Affiliation(s)
- F Thies
- Department of Biochemistry, University of Oxford, United Kingdom
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Abstract
The phylogenetic relationships among 18 species of Triatominae were inferred based on mitochondrial DNA (mtDNA) sequences. The species of Triatoma included 11 belonging to the infestans complex [T. infestans (Klug), T. guasayana Wygodzinsky & Abalos, T. sordida (Stål), T. platensis Neiva, T. brasiliensis Neiva, T. rubrovaria (Blanchard), T. vitticeps (Stål), T. delpontei Romaña & Abalos, T. maculata (Erichson), T. patagonica Del Ponte, and T. matogrossensis Leite & Barbosa] and four others of the same genus but of different complexes [T. circummaculata (Stål), T. protracta (Uhler), T. dimidiata (Latreille), and T. mazzottii Usinger]. As possible outgroups we used Mepraia spinolai Mazza, Panstrongylus megistus (Burmeister), and Rhodnius prolixus Stål. We analyzed mtDNA fragments of the 12S and 16S ribosomal RNA genes from each of the 18 species, as well as of the cytochrome oxidase I (COI) gene from nine. The 12S, 16S, and COI gene sequences were analyzed individually and combined. All of the phylogenetic analyses unambiguously supported two clusters: one including T. infestans, T. platensis, and T. delpontei, and the other T. sordida and T. mutagrossensis. Inclusion of T. circummaculata into the infestans complex was confirmed, although this is in disagreement with the morphological classification. On the other hand, our analyses showed that T. dimidiata is closely related to a phylosoma complex species, T. mazzottii. This is consistent with the tentative classification previously made based on morphological characters. The issue of the monophyly of the genus Triatoma remains unresolved.
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Affiliation(s)
- B A García
- Cátedra de Bioquímica y Biología Molecular, Facultad de Ciencias Médicas, Universidad Nacional de Córdoba, Argentina.
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35
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Thies F, Nebe-von-Caron G, Powell JR, Yaqoob P, Newsholme EA, Calder PC. Dietary supplementation with gamma-linolenic acid or fish oil decreases T lymphocyte proliferation in healthy older humans. J Nutr 2001; 131:1918-27. [PMID: 11435508 DOI: 10.1093/jn/131.7.1918] [Citation(s) in RCA: 153] [Impact Index Per Article: 6.7] [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: 11/13/2022] Open
Abstract
Animal and human studies have shown that greatly increasing the amounts of flax seed oil [rich in the (n-3) polyunsaturated fatty acid (PUFA) alpha-linolenic acid (ALNA)] or fish oil [FO; rich in the long chain (n-3) PUFA eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA)] in the diet can decrease mitogen-stimulated lymphocyte proliferation. The objective of this study was to determine the effect of dietary supplementation with moderate levels of ALNA, gamma-linolenic acid (GLA), arachidonic acid (ARA), DHA or FO on the proliferation of mitogen-stimulated human peripheral blood mononuclear cells (PBMC) and on the production of cytokines by those cells. The study was randomized, placebo-controlled, double-blinded and parallel. Healthy subjects ages 55-75 y consumed nine capsules/d for 12 wk; the capsules contained placebo oil (an 80:20 mix of palm and sunflower seed oils) or blends of placebo oil with oils rich in ALNA, GLA, ARA or DHA or FO. Subjects in these groups consumed 2 g of ALNA or 770 mg of GLA or 680 mg of ARA or 720 mg of DHA or 1 g of EPA plus DHA (720 mg of EPA + 280 mg of DHA) daily from the capsules. Total fat intake from the capsules was 4 g/d. The fatty acid composition of PBMC phospholipids was significantly changed in the GLA, ARA, DHA and FO groups. Lymphocyte proliferation was not significantly affected by the placebo, ALNA, ARA or DHA treatments. GLA and FO caused a significant decrease (up to 65%) in lymphocyte proliferation. This decrease was partly reversed by 4 wk after stopping the supplementation. None of the treatments affected the production of interleukin-2 or interferon-gamma by PBMC and none of the treatments affected the number or proportion of T or B lymphocytes, helper or cytotoxic T lymphocytes or memory helper T lymphocytes in the circulation. We conclude that a moderate level GLA or EPA but not of other (n-6) or (n-3) PUFA can decrease lymphocyte proliferation but not production of interleukin-2 or interferon-gamma.
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Affiliation(s)
- F Thies
- Department of Biochemistry, University of Oxford, Oxford, UK
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36
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Thies F, Nebe-von-Caron G, Powell JR, Yaqoob P, Newsholme EA, Calder PC. Dietary supplementation with eicosapentaenoic acid, but not with other long-chain n-3 or n-6 polyunsaturated fatty acids, decreases natural killer cell activity in healthy subjects aged >55 y. Am J Clin Nutr 2001; 73:539-48. [PMID: 11237929 DOI: 10.1093/ajcn/73.3.539] [Citation(s) in RCA: 130] [Impact Index Per Article: 5.7] [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: 11/14/2022] Open
Abstract
BACKGROUND Animal studies showed that dietary flaxseed oil [rich in the n-3 polyunsaturated fatty acid alpha-linolenic acid (ALA)], evening primrose oil [rich in the n-6 polyunsaturated fatty acid gamma-linolenic acid (GLA)], and fish oil [rich in the long-chain n-3 polyunsaturated fatty acids eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA)] can decrease natural killer (NK) cell activity. There have been no studies of the effect on NK cell activity of adding these oils to the diet of humans. OBJECTIVE Our objective was to determine the effect of dietary supplementation with oil blends rich in ALA, GLA, arachidonic acid (AA), DHA, or EPA plus DHA (fish oil) on the NK cell activity of human peripheral blood mononuclear cells. DESIGN A randomized, placebo-controlled, double-blind, parallel study was conducted. Healthy subjects aged 55-75 y consumed 9 capsules/d for 12 wk; the capsules contained placebo oil (an 80:20 mix of palm and sunflower seed oils) or blends of placebo oil and oils rich in ALA, GLA, AA, DHA, or EPA plus DHA. Subjects in these groups consumed 2 g ALA, 770 mg GLA, 680 mg AA, 720 mg DHA, or 1 g EPA plus DHA (720 mg EPA + 280 mg DHA) daily, respectively. Total fat intake from the capsules was 4 g/d. RESULTS The fatty acid composition of plasma phospholipids changed significantly in the GLA, AA, DHA, and fish oil groups. NK cell activity was not significantly affected by the placebo, ALA, GLA, AA, or DHA treatment. Fish oil caused a significant reduction (mean decline: 48%) in NK cell activity that was fully reversed by 4 wk after supplementation had ceased. CONCLUSION A moderate amount of EPA but not of other n-6 or n-3 polyunsaturated fatty acids can decrease NK cell activity in healthy subjects.
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Affiliation(s)
- F Thies
- Department of Biochemistry, University of Oxford, Oxford, United Kingdom
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Abstract
Analyses of inversions in polytene chromosomes indicate that, in West Africa, Anopheles gambiae (sensu stricto) may be a complex of more than a single taxonomic unit, and these units have been called chromosomal forms. In order to determine whether this genetic discontinuity extends to the rest of the genome, as would be expected if reproductive isolation exists, we have sequenced several regions of both the nuclear and mitochondrial genomes. With one exception, we were unable to identify any nucleotide sites that differentiate the chromosomal forms. The exception was the internal transcribed spacer (ITS) of the ribosomal DNA (rDNA). Three sites in this region distinguish Mopti chromosomal form from Savanna and Bamako in Mali and Burkina Faso. However, outside these two countries, the association between chromosomal form and rDNA type does not always hold. Together with the variants in the rDNA intergenic spacer (IGS) described in the accompanying papers (della Torre et al., 2001; Favia et al., 2001), we can recognize two major types of rDNA, Type I and Type II (corresponding to molecular forms S and M in della Torre et al., 2001). Type I is widespread in West Africa and is the only type found outside of West Africa (i.e. Tanzania and Madagascar). Type II is confined to West Africa. We were unable to detect any heterozygosity for the ITS types even in five collections containing both types. A sample from the island of São Tomé could not be classified into either Type I or Type II as the rDNA had characteristics of both. In general, our results confirm that An. gambiae is not a single pan-mictic unit, but exactly how to define any new taxa remains problematic. Finally, we have found minor variants of the major rDNA types fixed in local populations; contrary to most previous studies, this suggests restricted gene flow among populations of this species.
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Affiliation(s)
- G Gentile
- Department of Ecology and Evolutionary Biology, Yale University, 165 Prospect St., New Haven, CT 06520-8106, USA
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Miles EA, Thies F, Wallace FA, Powell JR, Hurst TL, Newsholme EA, Calder PC. Influence of age and dietary fish oil on plasma soluble adhesion molecule concentrations. Clin Sci (Lond) 2001; 100:91-100. [PMID: 11115423] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/18/2023]
Abstract
Soluble forms of intercellular adhesion molecule-1, vascular cell adhesion molecule-1 and E-selectin (termed sICAM-1, sVCAM-1 and sE-selectin respectively) are found in the plasma, and are elevated during inflammatory conditions in which there is increased expression of the cellular forms of the molecules on endothelial and other cells. sICAM-1, sVCAM-1 and sE-selectin concentrations were measured in the plasma of 140 healthy Caucasian subjects aged between 18 and 75 years (100 males/40 females). sICAM-1 concentrations varied between 59.9 and 299.7 ng/ml (median 150 ng/ml), sVCAM-1 concentrations varied between 222.8 and 1672.9 ng/ml (median 662 ng/ml) and sE-selectin concentrations varied between 12.4 and 90.3 ng/ml (median 45.5 ng/ml). There were significant positive linear correlations between age and the plasma concentrations of sICAM-1 (r=0.580; P<0.001) and sVCAM-1 (r=0.392; P<0.001), which were retained when the effects of gender, body mass index and fasting plasma triacylglycerol and total cholesterol concentrations were controlled for. The significant positive linear correlation between age and the plasma concentration of sE-selectin (r=0.234; P=0.027) was lost when other variables were controlled for. Male subjects <40 years of age had significantly lower plasma concentrations of both sICAM-1 and sVCAM-1 than males >55 years of age (both P<0.001), but the difference in plasma sE-selectin concentrations between the age groups did not reach significance (P=0.073). Subgroups of 16 males aged <40 years and 12 elderly subjects (>55 years of age) participated in a doubled-blind, placebo-controlled study of fish oil supplementation over 12 weeks. The level of eicosapentaenoic acid in plasma phospholipids did not change with placebo supplementation, but was significantly increased with fish oil supplementation in both young male and elderly subjects (median increase 200%). sICAM-1, sVCAM-1 and sE-selectin concentrations were unaffected by supplementation with placebo in either young male or elderly subjects. sICAM-1 concentrations were unaffected by fish oil supplementation. sE-selectin concentrations were significantly increased by fish oil supplementation in young males (P=0.043; median increase 38%), but fish oil tended to decrease plasma sE-selectin concentrations in the elderly subjects (P=0.075), with a median decrease of 11%. sVCAM-1 concentrations were unaffected by fish oil supplementation in young males. Fish oil supplementation significantly decreased plasma sVCAM-1 concentrations in the elderly subjects (P=0.043), with a median decrease of 20% (range 16-60%). These observations suggest that fish oil decreases endothelial activation in elderly subjects.
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Affiliation(s)
- E A Miles
- Institute of Human Nutrition, University of Southampton, Bassett Crescent East, Southampton SO16 7PX, UK
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39
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Abstract
Elderly humans have altered cellular redox levels and dysregulated immune responses, both of which are key events underlying the progression of chronic degenerative diseases of ageing, such as atherosclerosis and Alzeimer's disease. Poorly maintained cellular redox levels lead to elevated activation of nuclear transcription factors such as NFkB and AP-1. These factors are co-ordinately responsible for a huge range of extracellular signalling molecules responsible for inflammation, tissue remodelling, oncogenesis and apoptosis, progessess that orchestrate many of the degenerative processess associated with ageing. It is now clear that levels of endogenous anti-oxidants such as GSH decrease with age. This study aimed to investigate the potential of exogenous anti-oxidants to influence inflammatory responses and the ageing process itself. We investigated the potential of the dietary antioxidant, quercetin, to reverse the age related influences of GSH depletion and oxidative stress using in vitro human umbilical vein endothelial cells (HUVEC) and human skin fibroblast (HSF) cell models. Oxidative stress-induced inflammatory responses were investigated in a GSH depletion and a Phorbol 12-myristate 13-acetate (PMA)-induced stress model. As measured with a sensitive HPLC fluorescence method, GSH in HUVEC was depleted by the addition of L-buthionine-[S,R]-sulfoxiniine (BSO), a gamma-glutamylcysteine synthetase inhibitor, to the culture medium at a concentration of 0.25 mM. Time course studies revealed that the GSH half-life was 4.6 h in HUVEC. GSH depletion by BSO for 24 h led to a slight increase in intracellular adhesion molecule - 1 (ICAM1) expression and prostaglandin E2 (PGE2) secretion in both types of cells. However, GSH depletion markedly enhanced PMA-induced ICAM and PGE2 production in HUVEC. Responses were progressively elevated following prolonged BSO treatment. Inhibition studies showed that 1-(5-Isoquinolinylsulfonyl)-2-methylpiperazine (H7), a protein kinase C (PKC) inhibitor, not only abolished most of PMA-induced ICAM-1 expression and PGE2, production, but also eliminated GSH depletion-enhanced PMA stimulation. This enhancement was also inhibited by supplementation with quercetin. The results clearly demonstrate that GSH depletion increased the susceptibility of vascular endothelial cells and fibroblasts to oxidative stress associated inflammatory stimuli. This increased in vitro susceptibility may be extrapolated to the in vivo situation of ageing, providing a useful model to study the influence of micronutrients on the ageing process. In conclusion, these data suggest that dietary antioxidants could play a significant role in the reduction of inflammatory responses.
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Affiliation(s)
- H L Hu
- Molecular Physiology, Unilever Research Laboratory Colworth, Sharnbrook, Bedford MK44 1LQ, UK
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Nebe-von-Caron G, Stephens PJ, Hewitt CJ, Powell JR, Badley RA. Analysis of bacterial function by multi-colour fluorescence flow cytometry and single cell sorting. J Microbiol Methods 2000; 42:97-114. [PMID: 11000436 DOI: 10.1016/s0167-7012(00)00181-0] [Citation(s) in RCA: 296] [Impact Index Per Article: 12.3] [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: 11/26/2022]
Abstract
With the increased awareness of the problems associated with the growth dependent analysis of bacterial populations, direct optical detection methods such as flow cytometry have enjoyed increased popularity over the last few years. Among the analyses discussed here are: (1) Bacterial discrimination from other particles on the basis of nucleic acid staining, using sample disaggregation to provide fast reliable enumeration while minimizing data artefacts due to post sampling growth; (2) Determination of basic cell functions such as reproductive ability, metabolic activity and membrane integrity, to characterise the physiological state or degree of viability of bacteria; and (3) The use of single cell sorting onto agar plates, microscope slides or into multi-well plates to correlate viability as determined by cell growth with fluorescent labelling techniques. Simultaneous staining with different fluorochromes provides an extremely powerful way to demonstrate culture heterogeneity, and also to understand the functional differences revealed by each stain in practical applications. Analysis of bacterial fermentations showed a considerable drop (20%) in membrane potential and integrity during the latter stages of small scale (5L), well mixed fed-batch fermentations. These changes, not found in either batch or continuous culture fermentations, are probably due to the severe, steadily increasing stress associated with glucose limitation during the fed-batch process, suggesting 'on-line' flow cytometry could improve process control. Heat injured cells can already show up to 4 log of differences in recovery in different pre-enrichment media, thus contributing to the problem of viable but non-culturable cells (VBNC's). Cytometric cell sorting demonstrated decreasing recovery with increasing loss of membrane function. However, a new medium protecting the cells from intracellular and extracellular causes of oxidative stress improved recovery considerably. Actively respiring cells showed much higher recovery improvement than the other populations, demonstrating for the first time the contribution of oxidative respiration to intracellular causes of damage as a key part of the VBNC problem. Finally, absolute and relative frequencies of one species in a complex population were determined using immunofluorescent labelling in combination with the analysis of cell function. The detail and precision of multiparameter flow cytometric measurements of cell function at the single cell level now raise questions regarding the validity of classical, growth dependent viability assessment methods.
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Affiliation(s)
- G Nebe-von-Caron
- Unilever Research Colworth, Bedfordshire, MK44 1LQ, Sharnbrook, UK.
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Olson SC, Bockbrader H, Boyd RA, Cook J, Koup JR, Lalonde RL, Siedlik PH, Powell JR. Impact of population pharmacokinetic-pharmacodynamic analyses on the drug development process: experience at Parke-Davis. Clin Pharmacokinet 2000; 38:449-59. [PMID: 10843462 DOI: 10.2165/00003088-200038050-00005] [Citation(s) in RCA: 21] [Impact Index Per Article: 0.9] [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: 11/02/2022]
Abstract
BACKGROUND Continued scepticism about the benefits of population pharmacokinetics and/or population pharmacodynamics, here referred to collectively as the population approach, hampers its widespread application in drug development. At the same time the sources of this scepticism have not been clearly defined. In an attempt to capture and clearly define these concerns and to help communicate the value of the population approach in drug development at Parke-Davis we conducted a survey of customers within the company. The results of this survey are presented here. METHODS All drug development programmes conducted over the past 10 years that included a population approach in data analysis and interpretation were identified. A brief description of the population analysis was prepared together with a brief description of how the resulting information was used in each drug development programme. These synopses were forwarded to relevant members of each drug development team together with a survey designed to solicit opinions as to the relevance and impact of these analyses. RESULTS The most frequent use of information derived from population-based analysis was in labelling. In all cases of drugs making to New Drug Application (NDA) submission the analyses resulted in information that was included in approved or proposed labelling. In almost half of the cases summarised here (5 of 12), population-based analysis was perceived to have resulted in information that influenced the direction of individual development programmes. In many of these cases the information was serendipitous. It is also noted that most of these analyses were not the result of clearly defined objectives and prospective analysis plans. CONCLUSIONS Use of the population approach, even when applied retrospectively, may have value in complementing or supporting interpretation of other data collected during the course of a trial. Atypical systemic exposure is quickly and easily assessed for correlation with adverse events or exceptional efficacy in retrospective or ad hoc evaluation. Although we know of no direct evidence, it is possible that such use of population pharmacokinetic data has facilitated NDA review and approval by providing insight into the role of atypical systemic drug exposure in otherwise spurious events.
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Affiliation(s)
- S C Olson
- Parke-Davis Pharmaceutical Research Division, Warner Lambert Company, Ann Arbor, Michigan 48105, USA
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Caccone A, Gibbs JP, Ketmaier V, Suatoni E, Powell JR. Origin and evolutionary relationships of giant Galápagos tortoises. Proc Natl Acad Sci U S A 1999; 96:13223-8. [PMID: 10557302 PMCID: PMC23929 DOI: 10.1073/pnas.96.23.13223] [Citation(s) in RCA: 113] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Perhaps the most enduring debate in reptile systematics has involved the giant Galápagos tortoises (Geochelone nigra), whose origins and systematic relationships captivated Charles Darwin and remain unresolved to this day. Here we report a phylogenetic reconstruction based on mitochondrial DNA sequences from Galápagos tortoises and Geochelone from mainland South America and Africa. The closest living relative to the Galápagos tortoise is not among the larger-bodied tortoises of South America but is the relatively small-bodied Geochelone chilensis, or Chaco tortoise. The split between G. chilensis and the Galápagos lineage probably occurred 6 to 12 million years ago, before the origin of the oldest extant Galápagos island. Our data suggest that the four named southern subspecies on the largest island, Isabela, are not distinct genetic units, whereas a genetically distinct northernmost Isabela subspecies is probably the result of a separate colonization. Most unexpectedly, the lone survivor of the abingdoni subspecies from Pinta Island ("Lonesome George") is very closely related to tortoises from San Cristobal and Espanola, the islands farthest from the island of Pinta. To rule out a possible recent transplant of Lonesome George, we sequenced DNA from three tortoises collected on Pinta in 1906. They have sequences identical to Lonesome George, consistent with his being the last survivor of his subspecies. This finding may provide guidance in finding a mate for Lonesome George, who so far has failed to reproduce.
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Affiliation(s)
- A Caccone
- Department of Ecology and Evolutionary Biology, Yale Institute for Biospherics Studies, Yale University, New Haven, CT 06520-8106, USA
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Powell JR, Petrarca V, della Torre A, Caccone A, Coluzzi M. Population structure, speciation, and introgression in the Anopheles gambiae complex. Parassitologia 1999; 41:101-13. [PMID: 10697841] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/15/2023]
Abstract
We review here what is known about the population structure and evolutionary dynamics of members of the Anopheles gambiae complex with emphasis on the situation in West Africa. First, the importance of the 2nd chromosome inversion polymorphism is demonstrated especially in adaptation to levels of aridity, a major environmental variable in Africa. This affects the distribution of karyotypes on both a macro- and micro-geographic scale as well as temporally. Such differentiation leads to karyotypes being differentially effective transmitters of malaria and differentially susceptible to indoor residual spraying of insecticides. Second, we review the evidence that cryptic taxa, especially in An. gambiae s.s., exist. This observation stems from both karyotype studies and molecular studies. It is abundantly clear that West African populations of An. gambiae s.s. are often not panmictic units, with premating factors evidently acting to maintain distinct genetic forms. Third, we review phylogenetic studies that have revealed the presence of introgression between the two most important vectors, An. gambiae and An. arabiensis. This is most evident for the 2nd chromosome inversions. This interpretation of phylogenetic data is consistent with a direct laboratory study indicating inversions in this chromosome are stably maintained in back-crossed populations. All of this information has led to the view that members of the An. gambiae complex are highly variable with an abundance of adaptive genetic variation. This presents a significant challenge to vector control programs designed to reduce malaria in sub-Saharan Africa.
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Affiliation(s)
- J R Powell
- Department of Ecology and Evolutionary Biology, Yale University, New Haven, CT 06511, USA.
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Abstract
Four of the five tortoise species in Madagascar, Pyxis arachnoides, P. planicauda, Geochelone radiata, and G. yniphora, are endemic and on the verge of extinction. Their phylogenetic relationships remain controversial and unresolved. Here we address the phylogeny of this group using DNA sequences for the 12S and 16S rDNA and cyt b genes in mitochondrial DNA. As outgroups we used two species of Geochelone, pardalis (mainland Africa) and nigra (Galápagos), as well as a more distant North American tortoise, Gopherus polyphemus. We conclude that the two Pyxis species are sister taxa and are imbedded in the genus Geochelone, rendering this latter genus paraphyletic. There is moderate support for the sister status of the two Madagascar Geochelone and for the monophyletic origin of all four endemics, suggesting a single colonization of the island. The separation of Madagascar from other land masses (90-165 mya) predates the origin of the endemic tortoises (estimated to be 14-22 mya). This suggests founding by rafting, a process known to have occurred with other tortoises. The derived morphological divergence of the Pyxis species in a relatively short period of time (13-20 my) stands in contrast to the notoriously slow rate of morphological evolution in most lineages of Chelonia.
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Affiliation(s)
- A Caccone
- Dipartimento di Biologia, II Università di Roma "Tor Vergata," Rome, 00175, Italy
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Powell JR, Dada MA, Naidoo SR. Investigation of unnatural deaths--justice or travesty? S Afr Med J 1999; 89:246-8. [PMID: 10226666] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/12/2023] Open
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Caccone A, García BA, Mathiopoulos KD, Min GS, Moriyama EN, Powell JR. Characterization of the soluble guanylyl cyclase beta-subunit gene in the mosquito Anopheles gambiae. Insect Mol Biol 1999; 8:23-30. [PMID: 9927171 DOI: 10.1046/j.1365-2583.1999.810023.x] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
Abstract
Genomic DNA corresponding to the soluble guanylyl cyclase beta-subunit (GCSbeta) gene was cloned and sequenced from Anopheles gambiae. The sequence was 8103 bp long and presumably included the entire coding region. The deduced amino acid sequence was 71% and 62% similar to previously known Drosophila and vertebrate GCSbeta, while the C-terminus of A. gambiae GCSbeta was shorter. Because of the conserved characteristics in each functional domain, the high G+C% in the third codon positions compared to the introns, the lack of internal stop codons, and the fact that we identified the gene from a cDNA, we conclude that this A. gambiae gene is functional. This is the first detailed description of a guanylyl cyclase gene structure (e.g. intron-exon boundaries). Interestingly, within the fifth intron we found high similarity to the flanking regions of the Pegasus-27 transposable element and other noncoding regions of the A. gambiae genome.
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Affiliation(s)
- A Caccone
- Department of Ecology and Evolutionary Biology, Yale University, New Haven, Connecticut 06520-8106, USA.
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Thies F, Peterson LD, Powell JR, Nebe-von-Caron G, Hurst TL, Matthews KR, Newsholme EA, Calder PC. Manipulation of the type of fat consumed by growing pigs affects plasma and mononuclear cell fatty acid compositions and lymphocyte and phagocyte functions. J Anim Sci 1999; 77:137-47. [PMID: 10064037 DOI: 10.2527/1999.771137x] [Citation(s) in RCA: 25] [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] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
To investigate the immunological effect of feeding pigs different dietary lipids, 3-wk-old, weaned pigs were fed for 40 d on one of five diets, which differed only in the type of oil present (the oil contributed 5% by weight of the diet and the total fat content of the diets was 8% by weight). The oils used were soybean (control diet), high-oleic sunflower oil (HOSO), sunflower oil (SO), canola oil (CO), and fish oil (FO; rich in long-chain [n-3] polyunsaturared fatty acids). There were no significant differences in initial or final animal weights, weight gains, or health scores among the groups. There were no significant differences in the concentration of anti-Escherichia coli vaccine antibodies in the gut lumens of pigs fed the different diets. The fatty acid composition of the diet markedly affected the fatty acid composition of the plasma and of mononuclear cells (a mixture of lymphocytes, monocytes, and macrophages) prepared from the blood, lymph nodes, or thymus. The FO feeding resulted in a significant increase in the number of circulating granulocytes. The FO feeding significantly decreased the proportion of phagocytes engaged in uptake of E. coli and decreased the activity of those phagocytes that were active. The proliferation of lymphocytes in cultures of whole blood from pigs fed the HOSO, SO, or FO diets was less than in those from pigs fed the CO diet. Proliferation of lymph node lymphocytes from SO- or FO-fed pigs was less than that from control, CO-, or HOSO-fed pigs. The natural killer cell activity of blood lymphocytes from pigs fed the FO diet was significantly reduced compared with those from pigs fed the CO diet. The concentration of PGE2 in the medium of cultured blood, lymph node, or thymic mononuclear cells was lower if the cells came from pigs fed the FO diet. Thus, the type of oil included in the diet of growing pigs affects the numbers and functional activities of immune cells in different body compartments.
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Affiliation(s)
- F Thies
- Department of Biochemistry, University of Oxford, UK
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Thomas CV, McDaniel GM, Holzgrefe HH, Mukherjee R, Hird RB, Walker JD, Hebbar L, Powell JR, Spinale FG. Chronic dual inhibition of angiotensin-converting enzyme and neutral endopeptidase during the development of left ventricular dysfunction in dogs. J Cardiovasc Pharmacol 1998; 32:902-12. [PMID: 9869495 DOI: 10.1097/00005344-199812000-00006] [Citation(s) in RCA: 21] [Impact Index Per Article: 0.8] [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] [Indexed: 11/25/2022]
Abstract
Angiotensin-converting enzyme (ACE) inhibition as well as neutral endopeptidase (NEP) inhibition was demonstrated to influence hemodynamics in various cardiac disease states. However, specific effects of chronic combined ACE and NEP inhibition on left ventricular (LV) and myocyte geometry and function remain unclear. In this study, a dual-acting metalloprotease inhibitor (DMPI), which possesses both ACE and NEP inhibitory activity, was used in a rapid-pacing model of LV dysfunction. LV and myocyte geometry and function were examined in control dogs (n = 6), in dogs with pacing-induced LV dysfunction (216 +/- 2 beats/min, 28 days, n = 7), and in dogs with DMPI treatment during rapid pacing (10 mg/kg p.o., b.i.d., n = 6). With chronic rapid pacing, LV end-diastolic volume increased (84 +/- 4 vs. 49 +/- 3 ml), and LV ejection fraction decreased (38 +/- 3% vs. 68 +/- 3%) compared with control (p < 0.05). DMPI concomitantly administered during long-term rapid pacing did not change LV ejection fraction (35 +/- 3%), but LV end-diastolic volume was reduced (70 +/- 5 vs. 84 +/- 4 ml; p < 0.05) when compared with rapid pacing only. With long-term rapid pacing, myocyte cross-sectional area was decreased (278 +/- 5 vs. 325 +/- 5 microm2), and resting length increased (178 +/- 2 vs. 152 +/- 1 microm) when compared with control (p < 0.05). With DMPI concomitantly administered during rapid pacing, myocyte cross-sectional area (251 +/- 5 microm2) and resting length (159 +/- 4 microm) were reduced when compared with rapid pacing only (p < 0.05). Myocyte velocity of shortening decreased from control values with long-term rapid pacing (39.3 +/- 3.9 vs. 73.2 +/- 5.9 microm/s; p < 0.05) but improved with DMPI treatment during rapid pacing when compared with rapid pacing only (58.9 +/- 6.7 microm/s; p < 0.05). Myocyte velocity of shortening with beta-adrenergic-receptor stimulation (25 nM isoproterenol) was reduced from controls with rapid pacing (125 +/- 12 vs. 214 +/- 30 microm/s; p < 0.05) but was improved with DMPI treatment during rapid pacing when compared with rapid pacing only (178 +/- 12 microm/s; p < 0.05). In a model of rapid pacing-induced LV failure, concomitant DMPI treatment significantly reduced the degree of LV dilation with no apparent effect on LV pump function. At the level of the LV myocyte, long-term DMPI treatment with rapid pacing improved myocyte performance and beta-adrenergic response. Thus the improvement in isolated myocyte contractile function was not translated into improved global LV-pump performance. The mechanisms by which improved myocyte contractility was not translated into a beneficial effect on LV-pump function with DMPI treatment during rapid pacing remain speculative, but likely include significant changes in LV remodeling and loading conditions.
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Affiliation(s)
- C V Thomas
- Division of Cardiothoracic Surgery, Medical University of South Carolina, Charleston 29425, USA
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49
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Saad D, Mukherjee R, Thomas PB, Iannini JP, Basler CG, Hebbar L, O SJ, Moreland S, Webb ML, Powell JR, Spinale FG. The effects of endothelin-A receptor blockade during the progression of pacing-induced congestive heart failure. J Am Coll Cardiol 1998; 32:1779-86. [PMID: 9822109 DOI: 10.1016/s0735-1097(98)00439-2] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/17/2022]
Abstract
OBJECTIVES We sought to identify the effects of endothelin (ET) subtype-A (ET(A))) receptor blockade during the development of congestive heart failure (CHF) on left ventricle (LV) function and contractility. BACKGROUND Congested heart failure causes increased plasma levels of ET and ET(A) receptor activation. METHODS Yorkshire pigs were assigned to four groups: 1) CHF: 240 beats/min for 3 weeks; n=7; 2) CHF/ET(A)-High Dose: paced for 2 weeks then ET(A) receptor blockade (BMS 193884, 50 mg/kg, b.i.d.) for the last week of pacing; n=6; 3) CHF/ET(A)-Low Dose: pacing for 2 weeks then ET(A) receptor blockade (BMS 193884, 12.5 mg/kg, b.i.d.) for the last week, n=6; and 4) CONTROL: n=8. RESULTS Left ventricle fractional shortening decreased with CHF compared with control (12+/-1 vs. 39+/-1%, p < 0.05) and increased in the CHF/ET(A) High and Low Dose groups (23+/-3 and 25+/-1%, p < 0.05). The LV peak wall stress and wall force increased approximately twofold with CHF and remained increased with ET(A) receptor blockade. With CHF, systemic vascular resistance increased by 120%, was normalized in the CHF/ET(A) High Dose group, and fell by 43% from CHF values in the Low Dose group (p < 0.05). Plasma catecholamines increased fourfold in the CHF group and were reduced by 48% in both CHF/ET(A) blockade groups. The LV myocyte velocity of shortening was reduced with CHF (32+/-3 vs. 54+/-3 microm/s, p < 0.05), was higher in the CHF/ET(A) High Dose group (39+/-1 microm/s, p < 0.05), and was similar to CHF values in the Low Dose group. CONCLUSIONS ET(A) receptor activation may contribute to the progression of LV dysfunction with CHF.
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Affiliation(s)
- D Saad
- Division of Cardiothoracic Surgery, Medical University of South Carolina, Charleston 29425, USA
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Abstract
For more than 60 years, evolutionary cytogeneticists have been using naturally occurring chromosomal inversions to infer phylogenetic histories, especially in insects with polytene chromosomes. The validity of this method is predicated on the assumption that inversions arise only once in the history of a lineage, so that sharing a particular inversion implies shared common ancestry. This assumption of monophyly has been generally validated by independent data. We present the first clear evidence that naturally occurring inversions, identical at the level of light microscopic examination of polytene chromosomes, may not always be monophyletic. The evidence comes from DNA sequence analyses of regions within or very near the breakpoints of an inversion called the 2La that is found in the Anopheles gambiae complex. Two species, A. merus and A. arabiensis, which are fixed for the "same" inversion, do not cluster with each other in a phylogenetic analysis of the DNA sequences within the 2La. Rather, A. merus 2La is most closely related to strains of A. gambiae homozygous for the 2L+. A. gambiae and A. merus are sister taxa, the immediate ancestor was evidently homozygous 2L+, and A. merus became fixed for an inversion cytologically identical to that in A. arabiensis. A. gambiae is polymorphic for 2La/2L+, and the 2La in this species is nearly identical at the DNA level to that in A. arabiensis, consistent with the growing evidence that introgression has or is occurring between these two most important vectors of malaria in the world. The parallel evolution of the "same" inversion may be promoted by the presence of selectively important genes within the breakpoints.
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Affiliation(s)
- A Caccone
- Department of Ecology and Evolutionary Biology, Yale University, New Haven, Connecticut 06520-8106, USA
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