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Gerardi HK, Breen KJ, Guasco TL, Weddle GH, Gardenier GH, Laaser JE, Johnson MA. Survey of Ar-tagged predissociation and vibrationally mediated photodetachment spectroscopies of the vinylidene anion, C2H2-. J Phys Chem A 2010; 114:1592-601. [PMID: 20088616 DOI: 10.1021/jp9095419] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
We report predissociation spectra of Ar-tagged C(2)H(2)(-) and C(2)D(2)(-) anions, and explore vibrationally mediated photodetachment from various vibrational levels of the bare C(2)H(2)(-) ion using velocity-map imaging. Intense photodetachment resonances are observed in the C-H stretching region that are strongly correlated with vibrational hot bands in the anion photoelectron spectra, indicating that one-color, resonant two-photon photodetachment (R2PD) is complicated by excitation of vibrationally excited states with autodetaching upper levels embedded in the continuum. Isolation of the R2PD spectrum was achieved using a two-color, IR-IR scheme in which vibrational excitation and photodetachment were carried out in two separate laser interaction regions.
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Affiliation(s)
- Helen K Gerardi
- Sterling Chemistry Laboratory, Yale University, P.O. Box 208107, New Haven, Connecticut 06520, USA
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202
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Bishop AJ, Martin P, MacDonald M, Poon L, Jazwinski SM, Green RC, Gearing M, Markesbery WR, Woodard JL, Johnson MA, Tenover JS, Siegler IC, Rodgers WL, Hausman DB, Rott C, Davey A, Arnold J. Predicting happiness among centenarians. Gerontology 2010; 56:88-92. [PMID: 20110722 DOI: 10.1159/000272017] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2008] [Accepted: 11/24/2008] [Indexed: 11/19/2022] Open
Abstract
BACKGROUND Happiness is believed to evolve from the comparison of current circumstances relative to past achievement. However, gerontological literature on happiness in extreme old age has been limited. OBJECTIVE The purpose of this study was to determine how perceptions of health, social provisions, and economics link past satisfaction with life to current feelings of happiness among persons living to 100 years of age and beyond. METHODS A total of 158 centenarians from the Georgia Centenarian Study were included to conduct the investigation. Items reflecting congruence and happiness from the Life Satisfaction Index were used to evaluate a model of happiness. Pathways between congruence, perceived economic security, subjective health, perceived social provisions, and happiness were analyzed using structural equation modeling. RESULTS Congruence emerged as a key predictor of happiness. Furthermore, congruence predicted perceived economic security and subjective health, whereas perceived economic security had a strong influence on subjective health status. CONCLUSION It appears that past satisfaction with life influences how centenarians frame subjective evaluations of health status and economic security. Furthermore, past satisfaction with life is directly associated with present happiness. This presents implications relative to understanding how perception of resources may enhance quality of life among persons who live exceptionally long lives.
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Affiliation(s)
- Alex J Bishop
- Human Development and Family Science Department, Oklahoma State University, Stillwater, Okla 74074, USA. alex.bishop @ okstate.edu
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203
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Hensley B, Martin P, MacDonald M, Poon L, Jazwinski SM, Green RC, Gearing M, Markesbery WR, Woodard JL, Johnson MA, Tenover JS, Siegler IC, Rodgers WL, Hausman DB, Rott C, Davey A, Arnold J. Family history and adaptation among centenarians and octogenarians. Gerontology 2010; 56:83-7. [PMID: 20110721 DOI: 10.1159/000271955] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2008] [Accepted: 11/24/2008] [Indexed: 11/19/2022] Open
Abstract
BACKGROUND The purpose of this study was to analyze various 'family history' variables (i.e. childhood health, financial situation while growing up, living with grandparents before age 17, and number of children) among participants of the Georgia Centenarian Study. OBJECTIVE To determine whether family history variables predict critical outcome areas such as cognitive functioning, activities of daily living, mental health, and economic dependence. METHODS A total of 318 older adults (236 centenarians and 82 octogenarians) were assessed with regard to their mental status, ADL (activities of daily living) functioning, depression, family history, loneliness, and perceived economic status. RESULTS Analyses indicated that the number of children significantly predicted the ability to engage in activities of daily living and loneliness. In essence, the more children, the higher the activities of the daily living score and the lower the loneliness scores. In addition, childhood health significantly predicted loneliness. The poorer one's health in childhood, the higher the loneliness scores. CONCLUSION The results of this study confirm the importance of distal family history variables on present-day functioning.
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Affiliation(s)
- Bob Hensley
- The College of Saint Scholastica, Duluth, Minn 55811, USA. rhensley @ css.edu
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204
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Margrett J, Martin P, Woodard JL, Miller LS, MacDonald M, Baenziger J, Siegler IC, Davey A, Poon L, Jazwinski SM, Green RC, Gearing M, Markesbery WR, Johnson MA, Tenover JS, Rodgers WL, Hausman DB, Rott C, Arnold J. Depression among centenarians and the oldest old: contributions of cognition and personality. Gerontology 2010; 56:93-9. [PMID: 20110723 DOI: 10.1159/000272018] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2008] [Accepted: 11/24/2008] [Indexed: 12/16/2022] Open
Abstract
BACKGROUND An estimated 20% of adults over the age of 55 experience clinical mental disorders such as depression and anxiety. For older adults, mental health concerns are often undetected, concomitant with physical challenges, and ultimately go untreated. These realities have significant implications for older adults' day-to-day functioning, particularly among the oldest old. OBJECTIVE The present study examined the ability of cognition and personality in explaining depression within a sample of octogenarians and centenarians. METHODS Participants were assessed during the most recent cross-sectional data collection of the Georgia Centenarian Study. The final eligible sample included 76 octogenarians (mean: 84.25 years, SD: 2.82; range: 81-90) and 158 centenarians and near centenarians (mean: 99.82 years, SD: 1.72; range: 98-109). RESULTS Hierarchical regression analyses were conducted to examine the relation between key variables and depressive symptoms in the two age groups. Blocks entered into the analyses included: demographics (i.e. age group, residential status, sex, and ethnicity) and functioning, memory and problem-solving ability, and personality (i.e. extraversion and neuroticism). Models differed for octogenarians and centenarians. Decreased problem-solving ability was related to greater depressive symptoms among octogenarians. For centenarians, institutional residence and increased neurotic tendencies were related to greater depressive symptoms. CONCLUSION Study findings demonstrate the need to examine a variety of factors which influence mental health in later life and to consider the unique contexts and differential experiences of octogenarians and centenarians.
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205
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MacDonald M, Aneja A, Martin P, Margrett J, Poon LW, Jazwinski SM, Green RC, Gearing M, Markesbery WR, Woodard JL, Johnson MA, Tenover JS, Siegler IC, Rodgers WL, Hausman DB, Rott C, Davey A, Arnold J. Distal and proximal resource influences on economic dependency among the oldest old. Gerontology 2010; 56:100-5. [PMID: 20110724 DOI: 10.1159/000272025] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2008] [Accepted: 11/24/2008] [Indexed: 11/19/2022] Open
Abstract
BACKGROUND As exceptional survivors, centenarians may have characteristics that reduce their dependency on family and community support systems despite the expectation that their extreme age creates a burden on those systems. The Georgia Centenarian Study obtained information about assistance for income, medical care, and caregiving of all types for a sample of centenarians and octogenarians. Previous studies have not established which characteristics may contribute to economic dependency among the oldest old. OBJECTIVE To identify distal and proximal resource influences on economic dependency, considering past lifestyle, proximal health, economic resources, personality, and coping behavior. METHODS Analysis sample sizes ranged from 109 to 138 octogenarians and centenarians. Blockwise multiple regressions predicted whether they received income assistance, number of medical care events, number of caregiving types, and total caregiving hours. RESULTS Past life style, gender, ethnicity, socioeconomic status, functional health, and coping were not related to economic dependency. With the exception of the number of types of care, centenarians were not more dependent than octogenarians. Cognitive ability had the strongest effects for medical care and caregiving services. 'Extraversion', 'ideas', 'neuroticism', and 'competence' personality factors had significant effects for caregiving types and total hours of care received. CONCLUSION Monitoring and intervention to maintain cognitive ability are critical practices for autonomy and reduced economic dependency among the oldest old. Psychological resources are more important influences on social support than functional health and other proximal economic resources.
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Affiliation(s)
- Maurice MacDonald
- Human Development and Family Studies, Iowa State University, Ames, Iowa, USA. morey @ ksu.edu
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206
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Randall GK, Martin P, McDonald M, Poon LW, Jazwinski SM, Green RC, Gearing M, Markesbery WR, Woodard JL, Johnson MA, Tenover JS, Siegler IC, Rodgers WL, Hausman DB, Rott C, Davey A, Arnold J. Social resources and longevity: findings from the Georgia centenarian study. Gerontology 2010; 56:106-11. [PMID: 20110725 DOI: 10.1159/000272026] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2008] [Accepted: 11/24/2008] [Indexed: 11/19/2022] Open
Abstract
BACKGROUND As the proportion of adults aged 85 and older increases, investigations of resources essential for adapting to the challenges of aging are required. OBJECTIVE To comprehensively investigate the social resources of cognitively intact centenarians participating in the Georgia Centenarian Study and the association between these resources and residence status. METHODS Two widely used measures of social resources were investigated among participants living in private homes, personal care facilities, and nursing homes. Logistic regression was used to determine significant predictors of nursing home residence. RESULTS Differences in levels of social resources were found between centenarians and octogenarians, and among centenarians in different living situations. Analyses revealed differential findings between self- and proxy reports. Controlling for education, activities of daily living, and financial ability to meet needs, only one of the two social resources measures significantly reduced the odds of nursing home residence. CONCLUSION The findings of this study add to the existing literature on one of the basic adaptive resources (social resources) for centenarians. Whether a more specific assessment of network contact is employed, or a more global assessment is used, differences in these constructs exist between centenarians and octogenarians, among centenarians in differing living conditions, and across types of informants. Researchers examining the different resources that may contribute to extraordinary longevity and positive adaptation may find it essential to differentiate between the oldest old and centenarians, and to account for differences based upon measure, reporter type, and centenarian residence status.
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Affiliation(s)
- G Kevin Randall
- Family and Consumer Sciences, Bradley University, Peoria, Ill 61625, USA. krandall @ bradley.edu
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208
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Relph RA, Guasco TL, Elliott BM, Kamrath MZ, McCoy AB, Steele RP, Schofield DP, Jordan KD, Viggiano AA, Ferguson EE, Johnson MA. How the Shape of an H-Bonded Network Controls Proton-Coupled Water Activation in HONO Formation. Science 2010; 327:308-12. [DOI: 10.1126/science.1177118] [Citation(s) in RCA: 91] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/02/2022]
Affiliation(s)
- Rachael A. Relph
- Department of Chemistry, Yale University, Post Office Box 208107, New Haven, CT 06520, USA
| | - Timothy L. Guasco
- Department of Chemistry, Yale University, Post Office Box 208107, New Haven, CT 06520, USA
| | - Ben M. Elliott
- Department of Chemistry, Yale University, Post Office Box 208107, New Haven, CT 06520, USA
| | - Michael Z. Kamrath
- Department of Chemistry, Yale University, Post Office Box 208107, New Haven, CT 06520, USA
| | - Anne B. McCoy
- Department of Chemistry, The Ohio State University, 100 West 18th Avenue, Columbus, OH 43210, USA
| | - Ryan P. Steele
- Department of Chemistry, Yale University, Post Office Box 208107, New Haven, CT 06520, USA
| | - Daniel P. Schofield
- Department of Chemistry, University of Pittsburgh, Pittsburgh, PA 15260, USA
| | - Kenneth D. Jordan
- Department of Chemistry, University of Pittsburgh, Pittsburgh, PA 15260, USA
| | - Albert A. Viggiano
- Air Force Research Laboratory, Space Vehicles Directorate, Hanscom Air Force Base, MA 01731, USA
| | - Eldon E. Ferguson
- Climate Monitoring and Diagnostics Laboratory, National Oceanic and Atmospheric Administration, Boulder, CO 80305, USA
| | - Mark A. Johnson
- Department of Chemistry, Yale University, Post Office Box 208107, New Haven, CT 06520, USA
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Abstract
Pollen tubes grow rapidly in a strictly polarized manner as they transport male reproductive cells through female flower tissues to bring about fertilization. Vegetative pollen tube cells are an excellent model system to investigate processes underlying directional cell expansion. In this chapter, we describe materials and methods required for (1) the identification of novel factors essential for polarized cell growth through the isolation and analysis of Arabidopsis mutants with defects in pollen tube growth and (2) the detailed functional characterization of pollen tube proteins based on transient transformation and microscopic analysis of cultured tobacco pollen tubes.
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Affiliation(s)
- Mark A Johnson
- Department of Molecular Biology, Cell Biology and Biochemistry, Brown University, Providence, RI, USA
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210
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Horvath S, McCoy AB, Elliott BM, Weddle GH, Roscioli JR, Johnson MA. Anharmonicities and Isotopic Effects in the Vibrational Spectra of X−·H2O, ·HDO, and ·D2O [X = Cl, Br, and I] Binary Complexes. J Phys Chem A 2009; 114:1556-68. [DOI: 10.1021/jp9088782] [Citation(s) in RCA: 60] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
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211
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Muraoka A, Inokuchi Y, Hammer NI, Shin JW, Johnson MA, Nagata T. Structural evolution of the [(CO2)n(H2O)]- cluster anions: quantifying the effect of hydration on the excess charge accommodation motif. J Phys Chem A 2009; 113:8942-8. [PMID: 19603758 DOI: 10.1021/jp903578e] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
The [(CO2)n(H2O)]- cluster anions are studied using infrared photodissociation (IPD) spectroscopy in the 2800-3800 cm(-1) range. The observed IPD spectra display a drastic change in the vibrational band features at n = 4, indicating a sharp discontinuity in the structural evolution of the monohydrated cluster anions. The n = 2 and 3 spectra are composed of a series of sharp bands around 3600 cm(-1), which are assignable to the stretching vibrations of H2O bound to C2O4- in a double ionic hydrogen-bonding (DIHB) configuration, as was previously discussed (J. Chem. Phys. 2005, 122, 094303). In the n > or = 4 spectrum, a pair of intense bands additionally appears at approximately 3300 cm(-1). With the aid of ab initio calculations at the MP2/6-31+G* level, the 3300 cm(-1) bands are assigned to the bending overtone and the hydrogen-bonded OH vibration of H2O bound to CO2- via a single O-H...O linkage. Thus, the structures of [(CO2)n(H2O)]- evolve with cluster size such that DIHB to C2O4- is favored in the smaller clusters with n = 2 and 3 whereas CO2- is preferentially stabilized via the formation of a single ionic hydrogen-bonding (SIHB) configuration in the larger clusters with n > or = 4.
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Affiliation(s)
- Azusa Muraoka
- Department of Basic Science, Graduate School of Arts and Sciences, The University of Tokyo, Komaba, Meguro-ku, Tokyo 153-8902, Japan
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212
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Edwards RD, Lam NL, Zhang L, Johnson MA, Kleinman MT. Nitrogen dioxide and ozone as factors in the availability of lead from lead-based paints. Environ Sci Technol 2009; 43:8516-8521. [PMID: 20028045 DOI: 10.1021/es901077m] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/28/2023]
Abstract
Lead-based paint remains a pervasive problem in U.S. cities, and an increasing problem in the developing world where it is still manufactured and used. Little attention has focused on the factors that increase the release of lead pigment granules from painted surfaces. Nitrogen dioxide (NO(2)) and ozone (O(3)) from transportation emissions in urban environments have the potential to react with and remove polymeric binders in paint, making pigment granules more available for subsequent transfer to hands on contact, or deposition in housedust. Here we show that exposure to NO(2) and O(3) increased the lead in wipe samples of stainless steel surfaces painted with alkyd low gloss solvent lead-based paint by 296% +/- 101 (or 0.24 microg/cm(2)) and 37% +/- 21 (or 0.025 microg/cm(2)), respectively, with corresponding changes in surface morphology indicated by reflectometry and scanning electron microscopy. Lead release from unexposed low gloss acrylic household paints was 40 times greater than comparable solvent based paints. Given that lead-based paint is still manufactured and used in many urban areas of the developing world where O(3) concentrations currently exceed historic U.S. concentrations, the interaction of air pollution with lead painted indoor surfaces may pose greater exposure risks for lead poisoning in children than previously anticipated.
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Affiliation(s)
- R D Edwards
- School of Medicine, University of California, Irvine, USA.
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213
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Frank AC, Johnson MA. Expressing the diphtheria toxin A subunit from the HAP2(GCS1) promoter blocks sperm maturation and produces single sperm-like cells capable of fertilization. Plant Physiol 2009; 151:1390-400. [PMID: 19734264 PMCID: PMC2773107 DOI: 10.1104/pp.109.144204] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/02/2009] [Accepted: 08/27/2009] [Indexed: 05/06/2023]
Abstract
After meiosis, the male germline of flowering plants undergoes two mitoses, producing two sperm that are carried within a pollen tube to an ovule. One sperm fuses with the egg to form the zygote and the other fuses with the central cell to form the primary endosperm. The mechanisms that control male germline development and gene expression, and ensure that sperm properly fuse with female gametes are just beginning to be understood. Expression of the potent translation inhibitor, diphtheria toxin A subunit, from the Arabidopsis (Arabidopsis thaliana) HAP2(GCS1) promoter blocked sperm development before the final cell division, resulting in pollen tubes that carried a single sperm-like cell rather than two sperm. These pollen tubes targeted ovules and fertilized either the egg or the central cell, producing seeds with either endosperm or an embryo, but not both. Endosperm-only seeds significantly outnumbered embryo-only seeds, suggesting that single sperm-like cells preferentially fuse with the central cell. These experiments show that de novo translation is required for completion of sperm development, that the HAP2(GCS1) promoter is very tightly controlled, and that disruption of gene expression can result in male germ cells with a bias for gamete fusion.
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Affiliation(s)
| | - Mark A. Johnson
- Department of Molecular Biology, Cell Biology and Biochemistry, Brown University, Providence, Rhode Island 02912
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214
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Penn DM, Fischer JG, Sun Lee J, Hausman DB, Johnson MA. High BMI and waist circumference are associated with a high prevalence of comorbidities in older Americans Act programs in Georgia senior centers. J Nutr Health Aging 2009; 13:827-32. [PMID: 19812874 DOI: 10.1007/s12603-009-0220-9] [Citation(s) in RCA: 14] [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: 12/18/2022]
Abstract
OBJECTIVE This study characterized the relationship of body mass index (BMI) and high waist circumference (WC) with the prevalence of selected comorbidities among older adults receiving nutrition and wellness services from Georgia's Older Americans Act programs at senior centers. METHODS Participants were a convenience sample (N = 759, mean age = 75 years, 81% female, 63% white, 36% black). Correction factors were applied to measured WC and to measured and self-reported height and weight. RESULTS The prevalence of several comorbidities showed striking relationships with WC and BMI, independent of age, gender, and race. CONCLUSION The health burden of overweight/obesity is very high in these older adults creating an urgent need for evidence-based nutrition, physical activity programs, and therapeutic lifestyle counseling to prevent and manage weight-related comorbidities.
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Affiliation(s)
- D M Penn
- Department of Foods and Nutrition,The University of Georgia, Athens, GA 30602 USA.
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215
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Relph RA, Bopp JC, Roscioli JR, Johnson MA. Structural characterization of (C2H2)1–6+ cluster ions by vibrational predissociation spectroscopy. J Chem Phys 2009; 131:114305. [DOI: 10.1063/1.3212595] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
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216
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Qin Y, Leydon AR, Manziello A, Pandey R, Mount D, Denic S, Vasic B, Johnson MA, Palanivelu R. Penetration of the stigma and style elicits a novel transcriptome in pollen tubes, pointing to genes critical for growth in a pistil. PLoS Genet 2009; 5:e1000621. [PMID: 19714218 PMCID: PMC2726614 DOI: 10.1371/journal.pgen.1000621] [Citation(s) in RCA: 281] [Impact Index Per Article: 18.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2009] [Accepted: 07/29/2009] [Indexed: 12/03/2022] Open
Abstract
Pollen tubes extend through pistil tissues and are guided to ovules where they release sperm for fertilization. Although pollen tubes can germinate and elongate in a synthetic medium, their trajectory is random and their growth rates are slower compared to growth in pistil tissues. Furthermore, interaction with the pistil renders pollen tubes competent to respond to guidance cues secreted by specialized cells within the ovule. The molecular basis for this potentiation of the pollen tube by the pistil remains uncharacterized. Using microarray analysis in Arabidopsis, we show that pollen tubes that have grown through stigma and style tissues of a pistil have a distinct gene expression profile and express a substantially larger fraction of the Arabidopsis genome than pollen grains or pollen tubes grown in vitro. Genes involved in signal transduction, transcription, and pollen tube growth are overrepresented in the subset of the Arabidopsis genome that is enriched in pistil-interacted pollen tubes, suggesting the possibility of a regulatory network that orchestrates gene expression as pollen tubes migrate through the pistil. Reverse genetic analysis of genes induced during pollen tube growth identified seven that had not previously been implicated in pollen tube growth. Two genes are required for pollen tube navigation through the pistil, and five genes are required for optimal pollen tube elongation in vitro. Our studies form the foundation for functional genomic analysis of the interactions between the pollen tube and the pistil, which is an excellent system for elucidation of novel modes of cell–cell interaction. For successful reproduction in flowering plants, a single-celled pollen tube must rapidly extend through female pistil tissue, locate female gametes, and deliver sperm. Pollen tubes undergo a dramatic transformation while growing in the pistil; they grow faster compared to tubes grown in vitro and become competent to perceive and respond to navigation cues secreted by the pistil. The genes expressed by pollen tubes in response to growth in the pistil have not been characterized. We used a surgical procedure to obtain large quantities of uncontaminated pollen tubes that grew through the pistil and defined their transcriptome by microarray analysis. Importantly, we identify a set of genes that are specifically expressed in pollen tubes in response to their growth in the pistil and are not expressed during other stages of pollen or plant development. We analyzed mutants in 33 pollen tube–expressed genes using a sensitive series of pollen function assays and demonstrate that seven of these genes are critical for pollen tube growth; two specifically disrupt growth in the pistil. By identifying pollen tube genes induced by the pistil and describing a mutant analysis scheme to understand their function, we lay the foundation for functional genomic analysis of pollen–pistil interactions.
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Affiliation(s)
- Yuan Qin
- Department of Plant Sciences, University of Arizona, Tucson, Arizona, United States of America
| | - Alexander R. Leydon
- Department of Molecular Biology, Cell Biology, and Biochemistry, Brown University, Providence, Rhode Island, United States of America
| | - Ann Manziello
- Arizona Cancer Center and Southwest Environmental Health Sciences Center, University of Arizona, Tucson, Arizona, United States of America
| | - Ritu Pandey
- Arizona Cancer Center and Southwest Environmental Health Sciences Center, University of Arizona, Tucson, Arizona, United States of America
| | - David Mount
- Arizona Cancer Center and Southwest Environmental Health Sciences Center, University of Arizona, Tucson, Arizona, United States of America
| | - Stojan Denic
- Department of Electrical and Computer Engineering, University of Arizona, Tucson, Arizona, United States of America
| | - Bane Vasic
- Department of Electrical and Computer Engineering, University of Arizona, Tucson, Arizona, United States of America
| | - Mark A. Johnson
- Department of Molecular Biology, Cell Biology, and Biochemistry, Brown University, Providence, Rhode Island, United States of America
- * E-mail: (MAJ); (RP)
| | - Ravishankar Palanivelu
- Department of Plant Sciences, University of Arizona, Tucson, Arizona, United States of America
- * E-mail: (MAJ); (RP)
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217
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Abstract
Gene silencing by DNA methylation and small RNAs is globally reconfigured during gametogenesis in Arabidopsis. Gene silencing by DNA methylation and small RNAs is globally reconfigured during gametogenesis in Arabidopsis, affecting transposon activity, gene regulation and development.
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Affiliation(s)
- Mark A Johnson
- Brown University, Department of Molecular Biology, Cell Biology, and Biochemistry, Providence, RI 02912, USA
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218
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Johnson MA, Moss RR, Munt B. Determining aortic stenosis severity: what to do when measuring left ventricular outflow tract diameter is difficult. J Am Soc Echocardiogr 2009; 22:452-3. [PMID: 19450741 DOI: 10.1016/j.echo.2009.03.018] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
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Abstract
OBJECTIVES The aims of the study were to describe the clinical presentation and renal and bone abnormalities in a case series of HIV-infected patients receiving treatment with tenofovir (TDF), and to recommend appropriate screening for toxicity related to TDF. METHODS Patients were identified from referrals to a specialist HIV renal clinic. Patients were included if treatment with TDF was assessed as the primary cause of the renal function impairment and clinical data were available prior to and following discontinuation of TDF treatment. Data were collected from case note review and clinic databases. RESULTS Twenty-two patients (1.6% of all those who received TDF) were identified with TDF-associated renal toxicity. All had normal serum creatinine prior to TDF therapy. All presented with proteinuria. On stopping TDF, renal function improved. Eight patients had confirmed Fanconi syndrome. Twelve patients presented with bone pain and osteomalacia was confirmed on an isotope bone scan in seven of these patients. The findings (in those patients tested) of tubular proteinuria, reduced tubular transport maximum of phosphate (TmP), and glycosuria were all consistent with the proximal tubule being the site of toxicity. CONCLUSION Renal toxicity remains a concern in patients treated with TDF. Clinical presentation may be with renal dysfunction, Fanconi syndrome or osteomalacia. Our investigations suggest proximal tubular toxicity as a common pathogenic mechanism.
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Mahungu TW, Smith CJ, Turner F, Egan D, Youle M, Johnson MA, Khoo S, Back DJ, Owen A. Cytochrome P450 2B6 516G→T is associated with plasma concentrations of nevirapine at both 200 mg twice daily and 400 mg once daily in an ethnically diverse population. HIV Med 2009; 10:310-7. [DOI: 10.1111/j.1468-1293.2008.00689.x] [Citation(s) in RCA: 61] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
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Kraft JC, Osterhaus GL, Ortiz AN, Garris PA, Johnson MA. In vivo dopamine release and uptake impairments in rats treated with 3-nitropropionic acid. Neuroscience 2009; 161:940-9. [PMID: 19362126 DOI: 10.1016/j.neuroscience.2009.03.083] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2009] [Revised: 03/14/2009] [Accepted: 03/30/2009] [Indexed: 11/17/2022]
Abstract
Recent evidence has suggested that mitochondrial dysfunction may lead to impaired neurotransmitter exocytosis in transgenic Huntington's disease (HD) model mice. To gain insight into the impact of mitochondrial impairment on striatal dopamine release in vivo, we used fast-scan cyclic voltammetry (FSCV) at carbon fiber microelectrodes to measure dopamine release and uptake kinetics in anesthetized Lewis rats continuously treated for 5 days with 3-nitropropionic acid (3NP). Our results indicate that, even though striatal dopamine content was unchanged, remotely stimulated dopamine release evoked per electrical stimulus pulse ([DA](p)) is decreased in 3NP-treated rats (33% of that observed in sham control rats) and that this decrease is uniform throughout all stereotaxic depths tested. Nevertheless, unlike data collected previously from transgenic HD model rodents, the maximum rate of dopamine uptake (V(max)) in 3NP-treated rats is diminished (30% of controls) while K(m) is unchanged. Treatment with 3NP also resulted in a corresponding decrease in locomotor activity, presumably due in part to the impaired dopamine release. These results indicate that dopamine release is degraded in this HD model, as is observed in transgenic HD model rodents; however, the results also imply that there are fundamental differences in dopamine uptake between 3NP-treated animals and transgenic animals.
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Affiliation(s)
- J C Kraft
- Department of Chemistry, The University of Kansas, Lawrence, KS 66045-7582, USA
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McCoy AB, Diken EG, Johnson MA. Generating Spectra from Ground-State Wave Functions: Unraveling Anharmonic Effects in the OH−·H2O Vibrational Predissociation Spectrum. J Phys Chem A 2009; 113:7346-52. [DOI: 10.1021/jp811352c] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Anne B. McCoy
- Department of Chemistry, The Ohio State University, Columbus, Ohio 43210
| | - Eric G. Diken
- Department of Chemistry, Yale University, New Haven, Connecticut 06520
| | - Mark A. Johnson
- Department of Chemistry, Yale University, New Haven, Connecticut 06520
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Street E, Curtis H, Sabin CA, Monteiro EF, Johnson MA. British HIV Association (BHIVA) national cohort outcomes audit of patients commencing antiretrovirals from naïve. HIV Med 2009; 10:337-42. [PMID: 19490183 DOI: 10.1111/j.1468-1293.2009.00692.x] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
OBJECTIVES The aim of this work was to audit the extent to which routine HIV care in the UK conforms with British HIV Association (BHIVA) guidelines and specifically the proportion of patients starting highly active antiretroviral therapy (HAART) who achieve the outcome of virological suppression below 50 HIV-1 RNA copies/mL within 6 months. METHODS A prospective cohort review of adults with HIV infection who started antiretroviral therapy (ART) for the first time between April and September 2006 was carried out using structured questionnaire forms. RESULTS A total of 1170 adults from 122 clinical sites participated in the review. Of these patients, 699 (59.7%) started ART at CD4 counts <200 cells/microL and 193 (16.5%) had not been tested for HIV drug resistance. Excluding patients with valid reasons for stopping short-term ART, 795 (73.5%) of 1081 patients had an undetectable viral load (VL) at follow-up. Detectable VL was strongly associated with pretreatment CD4 count below 50 cells/microL and pretreatment VL above 100 000 copies/mL, and was not associated with clinic location or case load. About a quarter of patients did not have a VL measurement during the first 6 weeks after starting ART. CONCLUSIONS The majority of patients who initiated ART at sites participating in this UK national audit were managed within the BHIVA guidelines and achieved virological suppression below 50 copies/mL around 6 months after commencing treatment. Poor VL outcomes were associated with very low CD4 cell count and/or high VL at baseline but not with clinic case load or location. There is an urgent need to diagnose patients at an earlier stage of their HIV disease.
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Affiliation(s)
- E Street
- Department of Genitourinary Medicine, Leeds General Infirmary, Leeds LS1 3EX, UK
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Abstract
Summary The use of highly active antiretroviral therapy in the treatment of HIV infection has resulted in significant reductions in mortality and morbidity worldwide. However, there is considerable interindividual variability in patient outcomes in terms of drug disposition, drug efficacy and adverse events. The basis of these differences is multifactorial, but host genetics are believed to play a significant part. To date, most attempts to explain this variability have focused on isolated single nucleotide polymorphisms. The most exciting development to date is the discovery of human leukocyte antigen subtype B*5701 (HLA B*5701) as a strong predictor of the abacavir hypersensitivity reaction. There is a gradual move away from single candidate gene analyses towards a high throughput whole genome approach. These studies must be performed on well characterized cohorts and reported associations must be validated in independent, ethnically diverse populations.
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Affiliation(s)
- T W Mahungu
- Department of HIV Medicine, Royal Free NHS Trust, Pond Street, London NW3 2QG
- Department of Pharmacology and Therapeutics, University of Liverpool, 70 Pembroke Place, Liverpool L69 3GF, UK
| | - M A Johnson
- Department of HIV Medicine, Royal Free NHS Trust, Pond Street, London NW3 2QG
| | - A Owen
- Department of Pharmacology and Therapeutics, University of Liverpool, 70 Pembroke Place, Liverpool L69 3GF, UK
| | - D J Back
- Department of Pharmacology and Therapeutics, University of Liverpool, 70 Pembroke Place, Liverpool L69 3GF, UK
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Elliott BM, Relph RA, Roscioli JR, Bopp JC, Gardenier GH, Guasco TL, Johnson MA. Isolating the spectra of cluster ion isomers using Ar-"tag" -mediated IR-IR double resonance within the vibrational manifolds: Application to NO2- *H2O. J Chem Phys 2009; 129:094303. [PMID: 19044866 DOI: 10.1063/1.2966002] [Citation(s) in RCA: 62] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022] Open
Abstract
We demonstrate a method for isolating the vibrational predissociation spectra of different structural isomers of mass-selected cluster ions based on a population-labeling double resonance scheme. This involves a variation on the "ion dip" approach and is carried out with three stages of mass selection in order to separate the fragment ion signals arising from a fixed-frequency population-monitoring laser and those generated by a scanned laser that removes population of species resonant in the course of the scan. We demonstrate the method on the Ar-tagged NO(2) (-)H(2)O cluster, where we identify the spectral patterns arising from two isomers. One of these structures features accommodation of the water molecule in a double H-bond arrangement, while in the other, H(2)O attaches in a single ionic H-bond motif where the nominally free OH group is oriented toward the N atom of NO(2) (-). Transitions derived from both the NO(2) (-) and H(2)O constituents are observed for both isomers, allowing us to gauge the distortions suffered by both the ion and solvent molecules in the different hydration arrangements.
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Affiliation(s)
- Ben M Elliott
- Sterling Chemistry Laboratory, Yale University, P.O. Box 208107, New Haven, Connecticut 06520, USA
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Relph RA, Elliott BM, Weddle GH, Johnson MA, Ding J, Jordan KD. Vibrationally Induced Interconversion of H-Bonded NO2−·H2O Isomers within NO2−·H2O·Arm Clusters Using IR−IR Pump−Probe through the OH and NO Stretching Vibrations. J Phys Chem A 2009; 113:975-81. [DOI: 10.1021/jp808283r] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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Smith CJ, Phillips AN, Dauer B, Johnson MA, Lampe FC, Youle MS, Tyrer M, Staszewski S. Factors associated with viral rebound among highly treatment-experienced HIV-positive patients who have achieved viral suppression. HIV Med 2009; 10:19-27. [DOI: 10.1111/j.1468-1293.2008.00650.x] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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Johnson MA, Davey A, Park S, Hausman DB, Poon LW. Age, race and season predict vitamin D status in African American and white octogenarians and centenarians. J Nutr Health Aging 2008; 12:690-5. [PMID: 19043643 PMCID: PMC2978665 DOI: 10.1007/bf03028616] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.9] [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: 12/17/2022]
Abstract
OBJECTIVE Poor vitamin D status has been associated with osteoporosis, falls, cardiovascular diseases, cancer, autoimmune diseases, pain, nursing home placement, and other age-related conditions, but little is known about the prevalence and predictors of vitamin D status in those aged 80 and older. Thus, this study tested the hypothesis that vitamin D status would be 1) poorer in a population-based multi-ethnic sample of centenarians as compared with octogenarians and 2) predicted by specific dietary, demographic or environmental factors. DESIGN Cross-sectional population-based analyses. SETTING Northern Georgia in the United States. PARTICIPANTS Men and women aged 80 to 89 (octogenarians, n=80) and 98 and older (centenarians, n=237). MEASUREMENTS Regression analyses were used to examine the associations of serum 25-hydroxyvitamin D [25(OH)D] with age, gender, race, living arrangements, dairy food intake, supplement intake, and season. RESULTS The prevalence of vitamin D insufficiency [25(OH)D<50 nmol/L] was higher in centenarians than in octogenarians (p<0.02). In logistic regression analyses, the risk of being vitamin D insufficient was significantly increased by being a centenarian vs. octogenarian (p<0.005) and by being African American vs. white (p<0.001) and decreased by taking a supplement with vitamin D (p<0.001) or by having vitamin D status measured in the summer or fall (each p<0.05), compared with spring. CONCLUSIONS Centenarians and octogenarians are at high risk for vitamin D insufficiency for many of the same reasons identified in younger populations. Given the numerous potential adverse consequences of poor vitamin D status, efforts are needed to ensure vitamin D adequacy in these older adults.
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Affiliation(s)
- M A Johnson
- The University of Georgia, Department of Foods and Nutrition, 280 Dawson Hall, Athens, GA 30602, USA.
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Gardenier GH, Roscioli JR, Johnson MA. Intermolecular Proton Binding in the Presence of a Large Electric Dipole: Ar-Tagged Vibrational Predissociation Spectroscopy of the CH3CN·H+·OH2 and CH3CN·D+·OD2 Complexes. J Phys Chem A 2008; 112:12022-6. [DOI: 10.1021/jp800948s] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Affiliation(s)
- George H. Gardenier
- Sterling Chemistry Laboratory, Department of Chemistry, Yale University, P.O. Box 208107, New Haven, Connecticut 06520
| | - Joseph R. Roscioli
- Sterling Chemistry Laboratory, Department of Chemistry, Yale University, P.O. Box 208107, New Haven, Connecticut 06520
| | - Mark A. Johnson
- Sterling Chemistry Laboratory, Department of Chemistry, Yale University, P.O. Box 208107, New Haven, Connecticut 06520
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Relph RA, Bopp JC, Johnson MA, Viggiano AA. Argon cluster-mediated isolation and vibrational spectra of peroxy and nominally D3h isomers of CO3− and NO3−. J Chem Phys 2008; 129:064305. [DOI: 10.1063/1.2958223] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022] Open
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232
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Johnson MA, Rostas J. Vibronic structure of the CO2+ion: reinvestigation of the antisymmetric stretch vibration in the [Xtilde], Ã, and [Btilde] states. Mol Phys 2008. [DOI: 10.1080/00268979500101521] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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233
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Herzmann C, Cuthbertson Z, Fosdick L, Fisher M, Nelson M, Perry N, Law M, Wand H, Janossy G, Johnson MA, Youle M. Long-term clinical and surrogate marker effects of subcutaneous intermittent interleukin-2 without antiretroviral therapy in HIV-infected patients. J Antimicrob Chemother 2008; 62:583-6. [PMID: 18587135 DOI: 10.1093/jac/dkn238] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
OBJECTIVES Subcutaneous administration of interleukin-2 (IL-2) has been shown to increase CD4 counts in HIV-infected patients. It remains unclear whether this effect is associated with a clinical benefit. PATIENTS AND METHODS We conducted a long-term follow-up in the cohort of the UK-Vanguard study in which three groups of 12 antiretroviral-naive subjects with CD4 cell counts >350 cells/mm(3) received no treatment or IL-2 at either 4.5 or 7.5 MIU twice daily in 5 day cycles, respectively. RESULTS Mean follow-up was 376 weeks. IL-2 therapy was associated with a higher area under the curve of CD4 cell count change from baseline at week 48 but not thereafter. HIV-RNA levels were unaffected. Highly active antiretroviral therapy (HAART) was initiated after a mean of 172, 175 and 152 weeks in the control group, low-dose and high-dose IL-2 treatment group, respectively, a statistically non-significant difference. There was a tendency to start HAART soon after discontinuation of IL-2 therapy which may have been triggered by the steep decay of CD4 counts. There were two serious adverse events in the control group, seven in the low-dose IL-2 group and eight in the high-dose IL-2 group. No pattern of disease was detected, making an association with IL-2 therapy unlikely. CONCLUSIONS We could detect neither a benefit of IL-2 therapy after week 48 nor delayed initiation of HAART. This is currently the longest follow-up data comparing IL-2 therapy with no therapy in antiretroviral-naive HIV-infected patients and does not show a persistent benefit of the intervention.
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Affiliation(s)
- C Herzmann
- Department of Infectious Diseases, Vivantes Auguste Viktoria Klinikum, Rubensstr. 125, 12159 Berlin, Germany.
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McCunn LR, Gardenier GH, Guasco TL, Elliott BM, Bopp JC, Relph RA, Johnson MA. Probing isomer interconversion in anionic water clusters using an Ar-mediated pump-probe approach: Combining vibrational predissociation and velocity-map photoelectron imaging spectroscopies. J Chem Phys 2008; 128:234311. [DOI: 10.1063/1.2932104] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023] Open
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235
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McCunn LR, Roscioli JR, Elliott BM, Johnson MA, McCoy AB. Why Does Argon Bind to Deuterium? Isotope Effects and Structures of Ar·H 5O 2 + Complexes. J Phys Chem A 2008; 112:6074-8. [DOI: 10.1021/jp802172q] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Laura R. McCunn
- Department of Chemistry, Yale University, New Haven, Connecticut 06520, and Department of Chemistry, The Ohio State University, Columbus, Ohio 43210
| | - Joseph R. Roscioli
- Department of Chemistry, Yale University, New Haven, Connecticut 06520, and Department of Chemistry, The Ohio State University, Columbus, Ohio 43210
| | - Ben M. Elliott
- Department of Chemistry, Yale University, New Haven, Connecticut 06520, and Department of Chemistry, The Ohio State University, Columbus, Ohio 43210
| | - Mark A. Johnson
- Department of Chemistry, Yale University, New Haven, Connecticut 06520, and Department of Chemistry, The Ohio State University, Columbus, Ohio 43210
| | - Anne B. McCoy
- Department of Chemistry, Yale University, New Haven, Connecticut 06520, and Department of Chemistry, The Ohio State University, Columbus, Ohio 43210
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Herzmann C, Whiting SJ, Thomas M, Byrne P, Johnson MA, Youle M. Pharmacokinetics of acetyl-L-carnitine given in single or multiple doses to HIV-1 Infected patients with toxic peripheral polyneuropathy. Open AIDS J 2008; 2:39-42. [PMID: 18923701 PMCID: PMC2556204 DOI: 10.2174/1874613600802010039] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/24/2008] [Revised: 05/19/2008] [Accepted: 05/23/2008] [Indexed: 11/22/2022] Open
Abstract
The use of nucleoside reverse transcriptase inhibitors in the treatment of HIV infection is associated with antiretroviral toxic polyneuropathy (ATN). Previous studies suggest that long term treatment with Acetyl-L-carnitine (ALCAR) 1.5 gram twice daily improves symptoms and promotes nerve regeneration. It is unknown whether the drug’s pharmacokinetic profile would allow for a once daily administration. Twenty three HIV-1 infected subjects taking ALCAR for ATN were enrolled in a cross over trial and switched from twice to once daily dosing. Their regimen was changed from 1.5g twice daily to 1g (4 patients), 2g (7), and 3g (12) once daily, respectively. Twelve healthy volunteers served as control. Plasma levels of ALCAR and its metabolite L-carnitine were measured. Patients receiving ALCAR had higher pre-dose levels than control subjects. Post dose levels were not significantly higher than pre dose levels in any treatment group. The pre / post dose ALCAR concentrations were 7.6 / 7.7, 7.1 / 6.8, 7.7 / 6.8, and 7.1 / 7.5 µmol/l for 1.5g twice daily, 1g once daily, 2g once daily, and 3g once daily, respectively. All values were significantly higher than the mean concentration in the control group (4.3 µmol/l). For ALCAR and L-carnitine, measurements for once daily regimens did not differ from the twice daily regimen. Once daily dosing of ALCAR can achieve similar plasma levels as twice daily dosing but intra-mitochondrial levels remain unknown. The pharmacokinetic profile of orally administered ALCAR is complex and likely to be highly affected by endogenous concentrations.
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Affiliation(s)
- C Herzmann
- Vivantes Auguste Viktoria Klinikum, Rubensstr. 125, D-12157 Berlin, Germany.
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Abstract
This review describes patterns of mortality among adults infected with HIV in the UK and assesses the contributions of late diagnosis of HIV infection and non-HIV-related disease to such mortality. In total, 387 adults with HIV who died between 1 October 2004 and 30 September 2005 after receiving care at 90 clinical centres in the UK were reviewed. Causes of death and scenarios accounting for death were measured. Of the 387 deaths, 218 (56.3%) were readily attributable to infection with HIV. Only 123 (31.8%) deaths were considered not directly related to HIV. Late diagnosis of HIV accounted for 24.0% of all deaths and 35.2% of HIV-related deaths. Infection with HIV remains the main cause of mortality among infected patients in the era of highly active antiretroviral therapy. Late diagnosis of infection with HIV may be the largest potentially remediable factor for HIV-associated death.
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Affiliation(s)
- S B Lucas
- Guy's and St Thomas' NHS Trust, London
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238
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Ho JD, Miner JR, Dawes DM, Johnson MA, Lundin EJ. Reply. Am J Emerg Med 2008. [DOI: 10.1016/j.ajem.2008.01.007] [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: 10/22/2022] Open
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239
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McCunn LR, Headrick JM, Johnson MA. Site-specific addition of D(2)O to the (H(2)O)(6)(-) "hydrated electron" cluster: isomer interconversion and substitution at the double H-bond acceptor (AA) electron-binding site. Phys Chem Chem Phys 2008; 10:3118-23. [PMID: 18688376 DOI: 10.1039/b801372a] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
Abstract
We report the results of an experimental study designed to establish whether, once formed, one of the isomer classes of the hydrated electron clusters, (H(2)O)(n)(-), can interconvert with others when a water molecule is added by condensation. This is accomplished in an Ar-cluster mediated approach where a single intact D(2)O molecule is collisionally incorporated into argon-solvated water hexamer anions, creating the isotopically labeled D(2)O.(H(2)O)(6)(-).Ar(n) heptamer anion. Photoelectron and infrared predissociation spectroscopies are employed both to characterize the isomers generated in the condensation event and to track the position that the D(2)O label adopts within these isomeric structures. Despite the fact that the water hexamer anion precursor clusters initially exist in the isomer I form, incorporation of D(2)O produces mostly isomers I' and II in the labeled heptamer, which bind the electron more (I') or less (II) strongly than does the isomer I class. Isomers I and I' are known to feature electron binding primarily onto a single water molecule that resides in an AA (A = H-bond acceptor) site in the network. Surprisingly, the D(2)O molecule can displace this special electron-binding H(2)O molecule such that the anionic cluster retains the high binding arrangement. In the more weakly binding isomer II clusters, the D(2)O molecule fractionates preferentially to sites that give rise to the vibrational signature of isomer II.
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Affiliation(s)
- Laura R McCunn
- Sterling Chemistry Laboratory, Yale University, P.O. Box 208107, New Haven, Connecticut 06520, USA
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Dawes DM, Ho JD, Johnson MA, Lundin E, Janchar TA, Miner JR. 15-Second conducted electrical weapon exposure does not cause core temperature elevation in non-environmentally stressed resting adults. Forensic Sci Int 2008; 176:253-7. [PMID: 17983716 DOI: 10.1016/j.forsciint.2007.09.014] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2007] [Revised: 07/15/2007] [Accepted: 09/22/2007] [Indexed: 11/30/2022]
Affiliation(s)
- Donald M Dawes
- Emergency Department, Lompoc District Hospital, Lompoc, CA, USA
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Roscioli JR, Hammer NI, Johnson MA, Diri K, Jordan KD. Exploring the correlation between network structure and electron binding energy in the (H2O)7− cluster through isomer-photoselected vibrational predissociation spectroscopy and ab initio calculations: Addressing complexity beyond types I-III. J Chem Phys 2008; 128:104314. [DOI: 10.1063/1.2827475] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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Madge S, Smith CJ, Lampe F, Sabin CA, Youle M, Johnson MA, Phillips AN. An audit of viral load in one clinical population to describe features of viraemic patients on antiretroviral therapy. HIV Med 2008; 9:208-13. [PMID: 18298577 DOI: 10.1111/j.1468-1293.2008.00548.x] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
OBJECTIVES To assess the prevalence of an undetectable viral load (VL) (<50 HIV-1 RNA copies/mL) in a clinical population and to identify those viraemic and at risk of failing antiretroviral therapy (ART). METHODS An audit of a complete clinical population on 1 January 2005 via a clinical database and clinical note review. RESULTS On 1 January 2005, 1910 patients were under care; 1229/1332 (92%) of those exposed to ART for >16 weeks had a VL of <50 copies/mL. We examined 49/56 case notes of viraemic patients to identify explanations for viraemia. Common reasons included previous initial mono- or dual therapy, adherence problems, more advanced HIV disease, concomitant medications, physical and mental health issues and being less well linked into the service. A review of these patients' current status on 1 April 2007 showed that six of the 49 had since died. However, of those still alive, 20 (47%) had a VL <500 copies/mL. CONCLUSIONS The proportion of patients on ART with detectable viraemia is low in current clinical practice. New drugs may help those who are failing because of resistance. However, there is a small minority of patients who, for various reasons, appear unable to maintain sufficient adherence to ART.
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Affiliation(s)
- S Madge
- Royal Free Centre for HIV Medicine, Royal Free and University College London Medical School, London, UK.
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Smith CJ, Lampe FC, Youle M, Johnson MA, Phillips AN. O333 Treatment discontinuation and virological failure amongst HIV-positive individuals starting second-line combination antiretroviral therapy (cART). J Int AIDS Soc 2008. [DOI: 10.1186/1758-2652-11-s1-o37] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
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Clumeck N, Clotet B, Johnson MA, Peeters M, Vingerhoets J, Beets G, De Smedt G. Virological response with fully active etravirine (ETR; TMC125) after 48 weeks of treatment: pooled results from the DUET-1 and DUET-2 trials. J Int AIDS Soc 2008. [DOI: 10.1186/1758-2652-11-s1-p23] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
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Mahungu TW, Else LJ, Smith CJ, Cuthbertson Z, Podlekareva D, Hay P, Dragsted UB, Khoo SH, Johnson MA, Back DJ, Youle M. A study to evaluate the efficacy, safety and tolerability of co-administered lopinavir/ritonavir (LPVr) and nevirapine (NVP) in HIV-infected adults. J Int AIDS Soc 2008. [DOI: 10.1186/1758-2652-11-s1-p6] [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: 11/10/2022] Open
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246
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Rubio R, Johnson MA, Haas BJ, Loeschel EA, Granier C, Jackson F, Pearce HC. Safety personalisation of ART therapy: what treatments do patients receive with the knowledge of their HLA-B*5701 status? J Int AIDS Soc 2008. [DOI: 10.1186/1758-2652-11-s1-p83] [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: 11/10/2022] Open
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247
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Abstract
OBJECTIVES The aims of the study were (i) to investigate the prevalence of overt and subclinical thyroid disease in HIV-positive patients in a London teaching hospital; (ii) to determine risk factors associated with the development of thyroid dysfunction, including highly active antiretroviral therapy (HAART) and individual antivirals, and (iii) to determine the occurrence of thyroid dysfunction longitudinally over 3 years. METHODS The study consisted of retrospective analyses of thyroid function tests (TFT) in HIV-positive patients. The period prevalence of and factors associated with clinical and subclinical thyroid dysfunction were investigated. Patients with normal TFT but previous thyroid disease were identified from pharmacy records and included in the overt category. RESULTS A total of 1565 patients (73% of the clinic population) had at least one TFT taken since 2001. Overall, 3584 samples were analysed. Of the patients included in the study, 1233 (79%) were male, 1043 (66%) were white and 365 (23%) were black African, and in 969 (62%) the main risk for HIV was homosexual sex. Median age at baseline was 37 years. Nine hundred patients (58%) were on HAART at the start of the study. Thirty-nine (2.5%) were found to have overt hypothyroidism, and eight (<1%) had overt hyperthyroidism. Sixty-one (4%) had subclinical hypothyroidism, five (<1%) had subclinical hyperthyroidism and 263 (17%) had a nonthyroidal illness. A normal TFT was obtained for 1118 patients (75.5%). Multivariate analysis suggested that no independent variables were significantly associated with overt hypothyroidism, including HAART and stavudine use specifically. Repeated measurements over 3 years were available for 825 patients and only eight new cases (1%) of overt thyroid disease occurred. CONCLUSIONS The prevalence of overt thyroid disease was low in this cohort, suggesting that screening is not warranted.
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Affiliation(s)
- S Madge
- Royal Free Centre for HIV Medicine and Department of Primary Care and Population Sciences, Royal Free and UC Medical School, Rowland Hill Street, London, UK.
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248
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Park S, Johnson MA, Shea Miller K, De Chicchis AR. Hearing loss and cardiovascular disease risk factors in older adults. J Nutr Health Aging 2007; 11:515-518. [PMID: 17985069] [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: 05/25/2023]
Affiliation(s)
- S Park
- Department of Foods and Nutrition, The University of Georgia, Dawson Hall, Athens, GA 30602, USA
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McCunn LR, Roscioli JR, Johnson MA, McCoy AB. An H/D Isotopic Substitution Study of the H5O2+·Ar Vibrational Predissociation Spectra: Exploring the Putative Role of Fermi Resonances in the Bridging Proton Fundamentals. J Phys Chem B 2007; 112:321-7. [DOI: 10.1021/jp075289m] [Citation(s) in RCA: 86] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Affiliation(s)
- Laura R. McCunn
- Sterling Chemistry Laboratory, Yale University, P. O. Box 208107, New Haven, Connecticut 06520
| | - Joseph R. Roscioli
- Sterling Chemistry Laboratory, Yale University, P. O. Box 208107, New Haven, Connecticut 06520
| | - Mark A. Johnson
- Sterling Chemistry Laboratory, Yale University, P. O. Box 208107, New Haven, Connecticut 06520
| | - Anne B. McCoy
- Department of Chemistry, The Ohio State University, Columbus, Ohio 43210
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250
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Ho JD, Dawes DM, Johnson MA, Lundin EJ, Miner JR. Impact of conducted electrical weapons in a mentally ill population: a brief report. Am J Emerg Med 2007; 25:780-5. [PMID: 17870481 DOI: 10.1016/j.ajem.2007.02.030] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2007] [Revised: 02/10/2007] [Accepted: 02/11/2007] [Indexed: 11/20/2022] Open
Abstract
INTRODUCTION Conducted electrical weapons (CEWs) are used by some law enforcement agencies to subdue mentally ill subjects who are combative, violent, or suicidal. The use of CEWs in this population is controversial. Proponents advocate CEW use to avoid other forms of escalated force. Opponents advocate against CEW use because of the potential for abuse. What is lacking in the medical literature is documentation of the impact on outcome that this technology may have when used in this population. This project represents an initial report in this area. METHODS A database of CEW use has been maintained since 1999 to which law enforcement agencies voluntarily report. This database was reviewed for occurrences of CEW use on mentally ill and suicidal subjects. Situation outcome and potential for law enforcement use of deadly force as an alternative were recorded. Data analysis was performed using descriptive statistics. RESULTS There were 10,608 reports of CEW use over a 72-month period. Of these, there were 2452 uses on mentally ill subjects; and of these, 1111 (45.3%) were in situations where lethal force by the law enforcement agency would have been justified or where the subject represented an imminent life threat to himself. CONCLUSION The mentally ill represents a significant portion of subjects upon whom CEWs are used. These data suggest frequent use of CEWs in situations where deadly force would otherwise be justified and in situations where subjects exhibit imminent danger to themselves. These data also suggest that escalation to deadly force was avoided in many mental illness and suicidal situations by the presence of a CEW.
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Affiliation(s)
- Jeffrey D Ho
- Department of Emergency Medicine, Hennepin County Medical Center, Minneapolis, MN, USA
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