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Smith GS, Archibald P, Thorpe RJ. Race and obesity disparities among adults living in gentrifying neighborhoods. J Racial Ethn Health Disparities 2023; 10:93-99. [PMID: 35083727 DOI: 10.1007/s40615-021-01199-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2021] [Revised: 11/24/2021] [Accepted: 11/29/2021] [Indexed: 02/03/2023]
Abstract
There is a paucity of research seeking to understand race disparities in obesity among individuals living in a gentrifying neighborhood. American Community Survey data were used to identify gentrifying neighborhoods. In a cross-sectional analysis, these data were then linked to the 2014 Medical Expenditure Panel Survey, yielding an analytic sample of 887 Black and White adults. Obesity was based on body mass index ≥ 30 kg/m2. After controlling for potential confounders, Black adults living in gentrifying neighborhoods had a higher prevalence of obesity (PR: 1.39; 95% CI: 1.03, 1.88) than White adults living in gentrifying neighborhoods. Gentrification may have no impact on reducing Black-White obesity disparities in the US.
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Affiliation(s)
- G S Smith
- Department of Environmental Health and Engineering, Johns Hopkins Bloomberg School of Public Health, Baltimore, MD, USA.
- Hopkins Center for Health Disparities Solutions, Johns Hopkins Bloomberg School of Public Health, Baltimore, MD, USA.
| | - P Archibald
- Department of Social Work, College of Staten Island-City University of New York School of Health Science, Staten Island, NY, USA
| | - R J Thorpe
- Hopkins Center for Health Disparities Solutions, Johns Hopkins Bloomberg School of Public Health, Baltimore, MD, USA
- Program for Research On Men's Health, Hopkins Center for Health Disparities Solutions, Johns Hopkins Bloomberg School of Public Health, Baltimore, MD, USA
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Ankner JF, Ashkar R, Browning JF, Charlton TR, Doucet M, Halbert CE, Islam F, Karim A, Kharlampieva E, Kilbey SM, Lin JYY, Phan MD, Smith GS, Sukhishvili SA, Thermer R, Veith GM, Watkins EB, Wilson D. Cinematic reflectometry using QIKR, the quite intense kinetics reflectometer. Rev Sci Instrum 2023; 94:013302. [PMID: 36725568 DOI: 10.1063/5.0122279] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/23/2022] [Accepted: 11/14/2022] [Indexed: 06/18/2023]
Abstract
The Quite Intense Kinetics Reflectometer (QIKR) will be a general-purpose, horizontal-sample-surface neutron reflectometer. Reflectometers measure the proportion of an incident probe beam reflected from a surface as a function of wavevector (momentum) transfer to infer the distribution and composition of matter near an interface. The unique scattering properties of neutrons make this technique especially useful in the study of soft matter, biomaterials, and materials used in energy storage. Exploiting the increased brilliance of the Spallation Neutron Source Second Target Station, QIKR will collect specular and off-specular reflectivity data faster than the best existing such machines. It will often be possible to collect complete specular reflectivity curves using a single instrument setting, enabling "cinematic" operation, wherein the user turns on the instrument and "films" the sample. Samples in time-dependent environments (e.g., temperature, electrochemical, or undergoing chemical alteration) will be observed in real time, in favorable cases with frame rates as fast as 1 Hz. Cinematic data acquisition promises to make time-dependent measurements routine, with time resolution specified during post-experiment data analysis. This capability will be deployed to observe such processes as in situ polymer diffusion, battery electrode charge-discharge cycles, hysteresis loops, and membrane protein insertion into lipid layers.
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Affiliation(s)
- J F Ankner
- Second Target Station Project, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831, USA
| | - R Ashkar
- Department of Physics, Virginia Tech, Blacksburg, Virginia 24061, USA
| | - J F Browning
- Neutron Sciences Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831, USA
| | - T R Charlton
- Neutron Sciences Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831, USA
| | - M Doucet
- Neutron Sciences Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831, USA
| | - C E Halbert
- Neutron Sciences Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831, USA
| | - F Islam
- Neutron Technologies Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831, USA
| | - A Karim
- Department of Chemical and Biomolecular Engineering, University of Houston, Houston, Texas 77204, USA
| | - E Kharlampieva
- Department of Chemistry, University of Alabama at Birmingham, Birmingham, Alabama 35294, USA
| | - S M Kilbey
- Department of Chemistry, University of Tennessee, Knoxville, Tennessee 37996, USA
| | - J Y Y Lin
- Second Target Station Project, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831, USA
| | - M D Phan
- Neutron Sciences Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831, USA
| | - G S Smith
- Neutron Sciences Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831, USA
| | - S A Sukhishvili
- Department of Materials Science and Engineering, Texas A&M University, College Station, Texas 77843, USA
| | - R Thermer
- Second Target Station Project, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831, USA
| | - G M Veith
- Chemical Sciences Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831, USA
| | - E B Watkins
- Neutron Sciences Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831, USA
| | - D Wilson
- Second Target Station Project, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831, USA
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Baartzes N, Stringer T, Seldon R, Warner DF, Taylor D, Wittlin S, Chibale K, Smith GS. Bioisosteric ferrocenyl aminoquinoline-benzimidazole hybrids: Antimicrobial evaluation and mechanistic insights. Eur J Med Chem 2019; 180:121-133. [PMID: 31301563 DOI: 10.1016/j.ejmech.2019.06.069] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2019] [Revised: 06/08/2019] [Accepted: 06/25/2019] [Indexed: 01/29/2023]
Abstract
Phenyl- and bioisosteric ferrocenyl-derived aminoquinoline-benzimidazole hybrid compounds were synthesised and evaluated for their in vitro antiplasmodial activity against the chloroquine-sensitive NF54 and multi-drug resistant K1 strains of the human malaria parasite, Plasmodium falciparum. All compounds were active against the two strains, generally showing enhanced activity in the K1 strain, with resistance indices less than 1. Cytotoxicity studies using Chinese hamster ovarian cells revealed that the hybrids were relatively non-cytotoxic and demonstrated selective killing of the parasite. Based on favourable in vitro antiplasmodial and cytotoxicity data, the most active phenyl (4c) and ferrocenyl (5b) hybrids were tested in vivo against the rodent Plasmodium berghei mouse model. Both compounds caused a reduction in parasitemia relative to the control, with 5c displaying superior activity (92% reduction in parasitemia at 4 × 50 mg/kg oral doses). The most active phenyl and ferrocenyl derivatives showed inhibition of β-haematin formation in a NP-40 detergent-mediated assay, indicating a possible contributing mechanism of antiplasmodial action. The most active ferrocenyl hybrid did not display appreciable reactive oxygen species (ROS) generation in a ROS-induced DNA cleavage gel electrophoresis study. The compounds were also screened for their in vitro activity against Mycobacterium tuberculosis. The hybrids containing a more hydrophobic substituent had enhanced activity (<32.7 μM) compared to those with a less hydrophobic substituent (>62.5 μM).
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Affiliation(s)
- N Baartzes
- Department of Chemistry, University of Cape Town, Rondebosch, 7701, Cape Town, South Africa
| | - T Stringer
- Department of Chemistry, University of Cape Town, Rondebosch, 7701, Cape Town, South Africa
| | - R Seldon
- Drug Discovery and Development Centre (H3D), Institute of Infectious Disease and Molecular Medicine, University of Cape Town, Rondebosch, 7701, Cape Town, South Africa
| | - D F Warner
- SAMRC/NHLS/UCT Molecular Mycobacteriology Research Unit, DST/NRF Centre of Excellence for Biomedical TB Research, Department of Clinical Laboratory Sciences, University of Cape Town, Rondebosch, 7701, Cape Town, South Africa; Wellcome Centre for Infectious Diseases Research in Africa, University of Cape Town, Rondebosch, 7701, South Africa
| | - D Taylor
- H3D, Division of Clinical Pharmacology, Department of Medicine, University of Cape Town, Observatory, 7925, Cape Town, South Africa
| | - S Wittlin
- Swiss Tropical and Public Health Institute, Socinstrasse 57, 4002, Basel, Switzerland; University of Basel, 4003, Basel, Switzerland
| | - K Chibale
- Department of Chemistry, University of Cape Town, Rondebosch, 7701, Cape Town, South Africa; South African Medical Research Council, Drug Discovery and Development Research Unit, Department of Chemistry and Institute of Infectious Disease and Molecular Medicine, University of Cape Town, Rondebosch, 7701, South Africa
| | - G S Smith
- Department of Chemistry, University of Cape Town, Rondebosch, 7701, Cape Town, South Africa.
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Harris NG, Paydar A, Smith GS, Lepore S. Diffusion MR imaging acquisition and analytics for microstructural delineation in preclinical models of TBI. J Neurosci Res 2019; 100:1128-1139. [PMID: 31044457 PMCID: PMC6824967 DOI: 10.1002/jnr.24416] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/02/2019] [Revised: 02/13/2019] [Accepted: 03/04/2019] [Indexed: 12/31/2022]
Abstract
Significant progress has been made toward improving both the acquisition of clinical diffusion-weighted imaging (DWI) data and its analysis in the uninjured brain, through various techniques including a large number of model-based solutions that have been proposed to fit for multiple tissue compartments, and multiple fibers per voxel. While some of these techniques have been applied to clinical traumatic brain injury (TBI) research, the majority of these technological enhancements have yet to be fully implemented in the preclinical arena of TBI animal model-based research. In this review, we describe the requirement for preclinical, MRI-based efforts to provide systematic confirmation of the applicability of some of these models as indicators of tissue pathology within the injured brain. We review how current DWI techniques are currently being used in animal TBI models, and describe how both acquisition and analytic techniques could be extended to leverage the progress made in clinical work. Finally, we highlight remaining gaps in the preclinical pipeline from data acquisition to final analysis that currently have no real, preclinical-based correlate.
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Affiliation(s)
- N G Harris
- Department of Neurosurgery, UCLA Brain Injury Research Centre, David Geffen School of Medicine, University of California at Los Angeles, Los Angeles, California.,UCLA Intellectual Development and Disabilities Research Center, David Geffen School of Medicine, University of California at Los Angeles, Los Angeles, California
| | - A Paydar
- Department of Neurosurgery, UCLA Brain Injury Research Centre, David Geffen School of Medicine, University of California at Los Angeles, Los Angeles, California
| | - G S Smith
- Department of Neurosurgery, UCLA Brain Injury Research Centre, David Geffen School of Medicine, University of California at Los Angeles, Los Angeles, California
| | - S Lepore
- Department of Neurosurgery, UCLA Brain Injury Research Centre, David Geffen School of Medicine, University of California at Los Angeles, Los Angeles, California
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Gordon AC, Gillespie C, Son J, Polhill T, Leibman S, Smith GS. Long-term outcomes of laparoscopic large hiatus hernia repair with nonabsorbable mesh. Dis Esophagus 2018; 31:4850447. [PMID: 29444215 DOI: 10.1093/dote/dox156] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/07/2017] [Accepted: 12/06/2017] [Indexed: 12/11/2022]
Abstract
The use of mesh to augment suture repair of large hiatus hernias remains controversial. Repair with mesh may help reduce the recurrence rate of primary repair, but concerns about the potential for serious complications, such as mesh erosion or stricturing, continue to limit its use. We aim to evaluate the long-term outcome of primary hiatus hernia repair with lightweight polypropylene mesh (TiMesh) specifically looking at rates of clinical recurrence, dysphagia, and mesh-related complications. From a prospectively maintained database, 50 consecutive patients who underwent elective primary laparoscopic hiatal hernia repair with TiMesh between January 2005 and December 2007 were identified. Case notes and postoperative endoscopy reports were reviewed. Clinical outcomes were evaluated using a structured questionnaire, including a validated dysphagia score. Of the 50 patients identified, 36 (72%) were contactable for follow-up. At a median follow-up of 9 years, the majority of patients (97%) regarded their surgery as successful. Twelve patients (33%) reported a recurrence of their symptoms, but only 4 (11%) reported that their symptoms were as severe as prior to the surgery. There was no significant difference between pre- and postoperative dysphagia scores. Postoperative endoscopy reports were available for 32 patients at a median time point of 4 years postoperatively, none of which revealed any mesh-related complications. One patient had undergone a revision procedure for a recurrent hernia at another institution. In this series, primary repair of large hiatus hernia with nonabsorbable mesh was not associated with any adverse effects over time. Patient satisfaction with symptomatic outcome remained high in the long term.
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Affiliation(s)
- A C Gordon
- Department of Upper Gastrointestinal Surgery, Royal North Shore Hospital, Sydney, New South Wales, Australia
| | - C Gillespie
- Department of Upper Gastrointestinal Surgery, Royal North Shore Hospital, Sydney, New South Wales, Australia
| | - J Son
- Department of Upper Gastrointestinal Surgery, Royal North Shore Hospital, Sydney, New South Wales, Australia
| | - T Polhill
- Department of Upper Gastrointestinal Surgery, Royal North Shore Hospital, Sydney, New South Wales, Australia
| | - S Leibman
- Department of Upper Gastrointestinal Surgery, Royal North Shore Hospital, Sydney, New South Wales, Australia
| | - G S Smith
- Department of Upper Gastrointestinal Surgery, Royal North Shore Hospital, Sydney, New South Wales, Australia
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Kang T, Qian S, Smith GS, Do C, Heller WT. Small-angle neutron scattering study of a dense microemulsion system formed with an ionic liquid. Soft Matter 2017; 13:7154-7160. [PMID: 28895963 DOI: 10.1039/c7sm01516j] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
Mixtures of water, octane and 1-octanol with 1-tetradecyl-3-methylimidazolium chloride (C14MIM·Cl), often referred to as a surface active ionic liquid (SAIL), form water-in-oil microemulsions that have potential application as extraction media for various metal ions. Here, we present a structural study by small-angle neutron scattering (SANS) of dense microemulsions formed by surfactant-rich mixtures of these four compounds to understand how the SAIL can be used to tune the structures and properties of the microemulsions. The SANS experiments revealed that the microemulsions formed are composed of two phases, a water-in-oil microemulsion and a bicontinuous microemulsion, which becomes the dominant phase at high surfactant concentration. In this concentration regime, the surfactant film becomes more rigid, having a higher bending modulus that results from the parallel stacking of the imidazolium ring of the SAIL. At lower surfactant concentrations, the molecular packing of the SAIL does not change with the water content of the microemulsion. The results presented here correlate well with previously observed changes in the interaction between the IL cation and metal ions (Y. Tong, L. Han and Y. Yang, Ind. Eng. Chem. Res., 2012, 51, 16438-16443), while the capacity of the microemulsion system for water remains high enough for using the system as an extraction medium.
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Affiliation(s)
- T Kang
- Biology and Soft Matter Division, Oak Ridge National Laboratory, Oak Ridge, TN 37831, USA.
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Zhu J, Han Y, Kumar R, He Y, Hong K, Bonnesen PV, Sumpter BG, Smith SC, Smith GS, Ivanov IN, Do C. Controlling molecular ordering in solution-state conjugated polymers. Nanoscale 2015; 7:15134-15141. [PMID: 26242896 DOI: 10.1039/c5nr02037a] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
Rationally encoding molecular interactions that can control the assembly structure and functional expression in a solution of conjugated polymers hold great potential for enabling optimal organic optoelectronic and sensory materials. In this work, we show that thermally-controlled and surfactant-guided assembly of water-soluble conjugated polymers in aqueous solution is a simple and effective strategy to generate optoelectronic materials with the desired molecular ordering. We have studied a conjugated polymer consisting of a hydrophobic thiophene backbone and hydrophilic, thermo-responsive ethylene oxide side groups, which shows a step-wise, multi-dimensional assembly in water. By incorporating the polymer into phase-segregated domains of an amphiphilic surfactant in solution, we demonstrate that both chain conformation and degree of molecular ordering of the conjugated polymer can be tuned in hexagonal, micellar and lamellar phases of the surfactant solution. The controlled molecular ordering in conjugated polymer assembly is demonstrated as a key factor determining the electronic interaction and optical function.
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Affiliation(s)
- J Zhu
- Center for Nanophase Materials Sciences, Oak Ridge National Laboratory, Oak ridge, TN 37831, USA
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Zhu J, Han Y, Kumar R, He Y, Hong K, Bonnesen PV, Sumpter BG, Smith SC, Smith GS, Ivanov IN, Do C. Correction: Controlling molecular ordering in solution-state conjugated polymers. Nanoscale 2015; 7:15507. [PMID: 26340069 DOI: 10.1039/c5nr90161h] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
Correction for 'Controlling molecular ordering in solution-state conjugated polymers' by J. Zhu et al., Nanoscale, 2015, DOI: 10.1039/c5nr02037a.
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Affiliation(s)
- J Zhu
- Center for Nanophase Materials Sciences, Oak Ridge National Laboratory, Oak ridge, TN 37831, USA
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Smith GS, Dischinger P, Tang Y. HAVE DECLINES IN ALCOHOL INVOLVEMENT FOR TRAFFIC INJURIES ALSO OCCURRED WITH OTHER INJURIES AND WHAT DO WE REALLY KNOW REGARDING ALCOHOL AND INJURY HOSPITALISATIONS? Inj Prev 2012. [DOI: 10.1136/injuryprev-2012-040580d.3] [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: 11/03/2022]
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Rockett IRH, Regier MD, Kapusta ND, Coben J, Miller TR, Hanzlick RL, Todd KH, Sattin RW, Kennedy LW, Kleinig J, Smith GS. Patterns and trends in leading causes of unintentional and violence-related injury mortality: United States, 2000–2009. Inj Prev 2012. [DOI: 10.1136/injuryprev-2012-040590w.49] [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: 11/04/2022]
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Eldin WS, Hirshon JM, Smith GS, Kamal AM, Abou-El-Fetouh A, El-Setouhy M. Disability adjusted life years (DALYs) due to occupational injuries in east delta region of Egypt. Inj Prev 2010. [DOI: 10.1136/ip.2010.029215.157] [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: 11/03/2022]
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Kraus MF, Smith GS, Butters M, Donnell AJ, Dixon E, Yilong C, Marion D. Effects of the dopaminergic agent and NMDA receptor antagonist amantadine on cognitive function, cerebral glucose metabolism and D2 receptor availability in chronic traumatic brain injury: A study using positron emission tomography (PET). Brain Inj 2009; 19:471-9. [PMID: 16134735 DOI: 10.1080/02699050400025059] [Citation(s) in RCA: 68] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
Abstract
PRIMARY OBJECTIVE This study was performed to assess effects of amantadine (AMH), a dopaminergic agent and NMDA antagonist, on chronic traumatic brain injury (TBI). The primary hypotheses were that amantadine treatment would result in executive function improvement and increased activity in pre-frontal cortex. RESEARCH DESIGN An open-label design was used. METHODS Twenty-two subjects underwent neuropsychological testing pre- and post-12 week treatment. Six subjects also underwent PET scanning. INTERVENTION Amantadine 400 mg was administered per day. RESULTS Significant improvements on tests of executive function were observed with treatment. Analysis of PET data demonstrated a significant increase in left pre-frontal cortex glucose metabolism. There was a significant positive correlation between executive domain scores and left pre-frontal glucose metabolism. CONCLUSIONS This is the first known study to assess amantadine in chronic TBI using PET and the data are consistent with the hypotheses. The conduction of further studies is warranted.
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Affiliation(s)
- M F Kraus
- Center for Cognitive Medicine, Department of Psychiatry, University of Illinois at Chicago, 912 S. Wood Street, Suite 235 (MC 913), Chicago, IL 60612, USA.
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Wade FM, Pavlakis N, Receveur I, Leibman S, Smith GS. The role of cancer Nurse coordinator in foregut malignancy: Workload and costing considerations in the Australian setting. J Clin Oncol 2009. [DOI: 10.1200/jco.2009.27.15_suppl.e20559] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
e20559 Background: Foregut (esophageal and gastric) malignancy (FM) encompasses a number of diseases with poor outlook and complex and often morbid treatment. In keeping with world wide trends, the investigation and management of patients with FM is undertaken in the context of a multidisciplinary group consisting medical, nursing and paramedical specialists. Crucial to the delivery of co-ordinated and compassionate care is the Cancer Nurse Co-ordinator (CNC). Further, the CNC is pivotal in ensuring that benchmarks regarding intervals from diagnosis, to multidisciplinary assessment to treatment commencement are met. The aim of this study was to quantify the workload of the CNC in a newly established esophagogastric surgical unit. Methods: Clinical data and data regarding workload of the CNC in our unit was recorded prospectively. Results: Of 218 patients with newly diagnosed FM referred to our unit between November 2005 and December 2008 198 (91%) were seen by the CNC. The number of cancers arising from the esophagus or esophagogastric junction was 135 (62%), stomach 78 (36%) and small bowel 5 (2%). The interval between CNC referral and initial contact was 4 days (range -13 to 40 days) and 89 (45%) patients were seen at the initial consultation with the surgeon. The mean number of CNC contacts with individual patients was 18 (range 1–76), comprising 9 (range 0–42) face to face consultations, 9 (range 0–58) telephone contacts and 0.2 (range 0–14) email contacts. Referrals to other support services were made for 164 (83%) patients with an average of 1 referral made per patient. This workload was carried out over 29 hours per fortnight at $43 AUD per hour. The average cost per patient with FM cared for by the CNC was $491 AUD ($349 USD). Conclusions: The complex care of patients with FM is augmented by the presence of a specialist CNC. The resource requirement for CNC funding is a small proportion on the costs of overall patient treatment and represents a prudent use of finite health care resources. No significant financial relationships to disclose.
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Affiliation(s)
- F. M. Wade
- Royal North Shore Hospital, Sydney, Australia
| | - N. Pavlakis
- Royal North Shore Hospital, Sydney, Australia
| | - I. Receveur
- Royal North Shore Hospital, Sydney, Australia
| | - S. Leibman
- Royal North Shore Hospital, Sydney, Australia
| | - G. S. Smith
- Royal North Shore Hospital, Sydney, Australia
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Smith GS, Minehan E. HP11�THE SUGSS DATABASE; A WEB BASED UPPER GI CANCER DATABASE. ANZ J Surg 2009. [DOI: 10.1111/j.1445-2197.2009.04920_11.x] [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: 10/20/2022]
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Radajewski R, Hazebroek EJ, Berry H, Leibman S, Smith GS. Short-term symptom and quality-of-life comparison between laparoscopic Nissen and Toupet fundoplications. Dis Esophagus 2008; 22:84-8. [PMID: 19018854 DOI: 10.1111/j.1442-2050.2008.00887.x] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
Laparoscopic antireflux surgery is an established method of treatment of gastroesophageal reflux disease (GERD). This study evaluates the efficacy of Nissen versus Toupet fundoplication in alleviating the symptoms of GERD and compares the two techniques for the development of post-fundoplication symptoms and quality of life (QOL) at 12 months post-surgery. In this prospective consecutive cohort study, 94 patients presenting for laparoscopic antireflux surgery underwent either laparoscopic Nissen fundoplication (LN) (n = 51) from February 2002 to February 2004 or a laparoscopic Toupet fundoplication (LT) (n = 43) from March 2004 to March 2006, performed by a single surgeon (G. S. S.). Symptom assessment, a QOL scoring instrument, and dysphagia questionnaires were applied pre- and postoperatively. At 12 months post-surgery, patient satisfaction levels in both groups were high and similar (LT: 98%, LN: 90%; P = 0.21). The proportion of patients reporting improvement in their reflux symptoms was similar in both groups (LT: 95%, LN: 92%; P = 0.68), as were post-fundoplication symptoms (LT: 30%, LN: 37%; P = 0.52). Six patients in the Nissen group required dilatation for dysphagia compared with one in the Toupet group (LT: 2%, LN: 12%; P = 0.12). One patient in the Nissen group required conversion to Toupet for persistent dysphagia (P = 0.54). In this series, overall symptom improvement, QOL, and patient satisfaction were equivalent 12 months following laparoscopic Nissen or Toupet fundoplication. There was no difference in post-fundoplication symptoms between the two groups, although there was a trend toward a higher dilatation requirement and reoperation after Nissen fundoplication.
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Affiliation(s)
- R Radajewski
- Department of Upper Gastrointestinal Surgery, Royal North Shore Hospital, Sydney, New South Wales, Australia
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Smith GS, Walford RL. Standardization and stability of platelet suspensions in the complement-fixation test for HL-A antigens. Tissue Antigens 2008; 1:14-22. [PMID: 5154365 DOI: 10.1111/j.1399-0039.1971.tb00072.x] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/14/2023]
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Gananadha S, Hazebroek EJ, Leibman S, Berry H, Osgood L, Shon IH, Pavlakis N, Marx G, Smith GS. The utility of FDG-PET in the preoperative staging of esophageal cancer. Dis Esophagus 2008; 21:389-94. [PMID: 19125791 DOI: 10.1111/j.1442-2050.2007.00802.x] [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] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
Accurate staging of esophageal cancer is important when determining which patients will potentially benefit from curative surgery. The aim of this study was to evaluate the incremental effect of 2-fluoro-2-deoxyglucose positron emission tomography (FDG-PET) when used in addition to standard staging modalities. Patients referred to two surgeons in an Australian metropolitan teaching hospital with esophageal or esophago-gastric junction malignancy between May 2002 and December 2006 were included. Patients who had undergone prereferral treatment with chemotherapy or radiotherapy were excluded. Patients undergoing resection for gastrointestinal stromal tumors or high-grade dysplasia within Barrett's esophagus were also excluded. Clinical and non-clinical data were recorded prospectively. Pretreatment staging included routine CT scan and selective endoscopic ultrasound (EUS). FDG-PET was performed in patients judged to have curable disease on CT scanning and EUS. From a total of 130 eligible patients, 76 were judged to have curable disease on the basis of CT and EUS findings. Of these 76 patients, 19 (25%) were excluded from surgery due to additional information obtained from FDG-PET. The addition of FDG-PET to routine preoperative staging resulted in the exclusion from surgery of 19 (25%) patients who prior to the introduction of FDG-PET would have undergone attempted resection. FDG-PET should be performed in all patients under consideration for esophagogastric resection in order to avoid resection in patients with disseminated disease.
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Affiliation(s)
- S Gananadha
- Department of Upper GI Surgery, Royal North Shore Hospital, St. Leonards, New South Wales, Australia
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Hazebroek EJ, Hazebroek FWJ, Leibman S, Smith GS. Total esophagogastric dissociation in adult neurologically impaired patients with severe gastroesophageal reflux: an alternative approach. Dis Esophagus 2008; 21:742-5. [PMID: 18459984 DOI: 10.1111/j.1442-2050.2008.00834.x] [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] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
Patients with neuromuscular impairment, such as cerebral palsy or myotonic dystrophy, often suffer from oropharyngeal neuromuscular incoordination and severe gastresophageal reflux (GER). In 1997, Bianchi proposed total esophagogastric dissociation (TEGD) as an alternative to fundoplication and gastrostomy to eliminate totally the risk of recurrence of GER in neurologically impaired children. Little information exists about the best management for adult patients with severe neurological impairment in whom recurrent GER develops after failed fundoplication. We present our experience in three adult patients with neurological impairment in whom TEGD with Roux-en-Y esophagojejunostomy and feeding gastrostomy was performed for permanent treatment of GER.
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Affiliation(s)
- E J Hazebroek
- Department of Upper Gastrointestinal Surgery, Royal North Shore Hospital, Sydney, NSW, Australia
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Abstract
Paraesophageal hernias (PEH) occur when there is herniation of the stomach through a dilated hiatal aperture. These hernias occur more commonly in the elderly, who are often not offered surgery despite the failure of medical treatment to address mechanical symptoms and life-threatening complications. The aim of this study was to assess the impact of laparoscopic repair of PEH on quality of life in an elderly population. Data were collected prospectively on 35 consecutive patients aged >70 years who had laparoscopic repair of a symptomatic PEH between December 2001 and September 2005. The change in quality of life was assessed using a validated questionnaire, the Quality of Life in Reflux and Dyspepsia questionnaire (QOLRAD), and by patient interviews. Patients were assessed preoperatively, and at 6 weeks, 6 months, 12 months, 1 year, and 2 years postoperatively. Mean patient age was 77 years (range 70-85); mean American Society of Anesthesiologists class was 2.7 (range 1-3). There were 28 women and 7 men. There was one readmission for acute reherniation, which required open revision. Total complication rate was 17.1%. All complications were treated without residual disability. There was no 30-day mortality, and median hospital stay was 3 days (range 2-14). Completed questionnaires were obtained in 30 of 35 patients (85.7%). There was a significant improvement in quality of life, as measured with QOLRAD, at all postoperative time points (P < 0.001). Laparoscopic PEH repair can be performed with acceptable morbidity in symptomatic patients refractory to conservative treatment and is associated with a significant improvement in quality of life. Our data support elective repair of symptomatic PEH in the elderly, a population who may not always be referred for a surgical opinion.
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Affiliation(s)
- E J Hazebroek
- Department of Upper Gastrointestinal Surgery, Royal North Shore Hospital, Sydney, NSW, Australia
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Hazebroek EJ, Koak Y, Berry H, Leibman S, Smith GS. Critical evaluation of a novel DualMesh repair for large hiatal hernias. Surg Endosc 2008; 23:193-6. [PMID: 18320282 DOI: 10.1007/s00464-008-9772-8] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2007] [Revised: 11/18/2007] [Accepted: 12/11/2007] [Indexed: 11/26/2022]
Abstract
BACKGROUND The use of mesh for laparoscopic repair of large hiatal hernias may reduce recurrence rates in comparison to primary suture repair. However, there is a potential risk of mesh-related oesophageal complications due to prosthesis erosion. The aim of this study was to critically evaluate a novel mesh (DualMesh) repair of hiatal hernias with particular reference to intraluminal erosion. METHOD Medical records of 19 patients who underwent laparoscopic hiatal hernia repair with DualMesh reinforcement of the crural closure were reviewed from a prospectively collected database. Quality of life and symptom analysis was performed using quality of life in reflux and dyspepsia (QOLRAD) questionnaires pre- and postoperatively after 6 weeks, 6 months, 1 year and 2 years. Barium studies were performed on patients pre-operatively and two years postoperatively to assess hernia recurrence. After 2 years, oesophagogastric endoscopy was performed to assess signs of erosion. RESULTS Mean patient age was 70.5 years (range 49-85 years). Two years after hiatal hernia repair, there was significant improvement in quality-of-life scores (QOLRAD: p < 0.001). Follow-up barium studies performed at 31.3 months (range 29-40 months) after surgery showed moderate recurrent hernias (>4 cm) in 1/14 patients (7%). Endoscopies performed at 34.4 months (range 28-41 months) after surgery did not show any signs of prosthetic erosion. CONCLUSION Laparoscopic reinforcement of primary hiatal closure with DualMesh leads to a durable repair in patients with large hiatal hernias. Long-term endoscopic follow-up did not show any signs of mesh erosion after prosthetic reinforcement of the crural repair.
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Affiliation(s)
- E J Hazebroek
- Department of Upper Gastrointestinal Surgery, Royal North Shore Hospital, Level 2, Vindin House, St Leonards, Sydney, NSW, 2065, Australia.
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Smith GS, Hazebroek EJ, Eckstein R, Berry H, Smith WM, Isaacson JR, Falk GL, Martin CJ. Evaluation of DualMesh for repair of large hiatus hernia in a porcine model. Surg Endosc 2007; 22:1625-31. [DOI: 10.1007/s00464-007-9669-y] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2007] [Revised: 09/13/2007] [Accepted: 10/04/2007] [Indexed: 11/24/2022]
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Verma SK, Sorock GS, Pransky GS, Courtney TK, Smith GS. Occupational physical demands and same-level falls resulting in fracture in female workers: an analysis of workers' compensation claims. Inj Prev 2007; 13:32-6. [PMID: 17296686 PMCID: PMC2610557 DOI: 10.1136/ip.2006.012492] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.6] [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: 11/04/2022]
Abstract
OBJECTIVES To examine the association between occupational physical demands and risk of same-level falls resulting in fracture in female workers' compensation claimants. METHODS From workers' compensation claims for same-level falls, 7286 female workers from three age groups (18-49, 50-59 and 60-79 years) were randomly selected. Levels of occupational physical activity, standing and sitting were assigned using occupational codes. Fracture occurrence was determined using the International Classification of Diseases codes. Risks of same-level falls resulting in fracture were compared by quartiles of physical activity, standing and sitting. RESULTS In the 18-49-year age group, physical activity, standing and sitting at work were not significantly associated with risk of same-level falls resulting in fracture (p value trend: 0.07, 0.18 and 0.10, respectively). In the 50-59 and 60-79-year age groups, increasing duration of standing and decreasing duration of sitting were associated with decreasing risk of same-level falls resulting in fracture (p value trend: standing<0.001, 0.01; sitting<0.001, 0.02). In the 50-59-year age group, the relative risks of same-level falls resulting in fracture were 0.53, 0.41 and 0.82 for the second, third and highest quartiles of physical activity, respectively, as compared with workers in the lowest quartile (95% confidence interval 0.35 to 0.80, 0.23 to 0.72, 0.56 to 1.21, respectively). In the 60-79-year age group, there was a similar, but not significant, U-shaped association between occupational physical activity and risk of same-level falls resulting in fracture. CONCLUSION Moderate occupational physical demands may be associated with a decreased risk of same-level fall resulting in fracture in female workers' compensation claimants>or=50 years of age.
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Affiliation(s)
- S K Verma
- Quantitative Analysis Unit, Liberty Mutual Research Institute for Safety, Hopkinton, Massachusetts 01748, USA.
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Smith GS, Sorock GS, Wellman HM, Courtney TK, Pransky GS. Blurring the distinctions between on and off the job injuries: similarities and differences in circumstances. Inj Prev 2007; 12:236-41. [PMID: 16887945 PMCID: PMC2586787 DOI: 10.1136/ip.2006.011676] [Citation(s) in RCA: 16] [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: 11/04/2022]
Abstract
OBJECTIVES To compare the causes of non-fatal work and non-work injuries and the places or environments where they occur. It has been suggested that many injuries may have similar etiologies on and off the job and thus involve some common prevention strategies. However lack of comparable data on work relatedness has prevented testing this proposition. METHODS The National Health Interview Survey (NHIS) now collects information on the cause, location, and work relatedness of all medically attended injuries. National US estimates of non-fatal work and non-work injuries were compared by cause and place/location for working age adults (18-64 years). RESULTS Overall 28.6% of injuries to working age adults were work related (37.5% among employed people). The causes and locations of many work and non-work injuries were similar. Falls, overexertion, and struck/caught by were leading causes for work and non-work injuries. Motor vehicle injuries were less likely to be work related (3.4% at work v 19.5% non-work) and overexertion injuries more likely to be work related (27.1% v 13.8%). Assaults were less than 1% of work injuries and 1.8% of non-work injuries. Both work and non-work injuries occurred in every location examined-including the home where 3.5% of injuries were work related. CONCLUSIONS Work and non-work injuries share many similarities suggesting opportunities to broaden injury prevention programs commonly restricted to one setting or the other. Comprehensive efforts to prevent both non-work and work injuries may result in considerable cost savings not only to society but also directly to employers, who incur much of the associated costs.
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Affiliation(s)
- G S Smith
- Liberty Mutual Research Institute for Safety, Hopkinton, MA 01748, USA.
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Jackson TA, Smith GS, Niblack TL. Heterodera glycines Infectivity and Egg Viability Following Nonhost Crops and During Overwintering. J Nematol 2005; 37:259-264. [PMID: 19262870 PMCID: PMC2620972] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/27/2023] Open
Abstract
The most effective management program for soybean cyst nematode, Heterodera glycines, is a crop rotation that uses nonhost crops and resistant soybean cultivars. However, little is known about the effects of rotation crops and overwintering on H. glycines biology. These experiments were initiated to determine the effects of seven alternative crops on H. glycines' ability to infect and mature on subsequent soybean crops, and to assess the viability of eggs during the overwintering months. Rotation studies were conducted for 2 years in each of two naturally infested fields, and overwintering tests were conducted in three consecutive growing seasons in one naturally infested field. Rotation crop and fallow treatments did not have a consistent effect on the ability of H. glycines to infect soybean or mature. Soybean yields were often higher following fallow or a nonhost crop than following soybean, although not usually significantly so. Heterodera glycines egg viability did not differ (P < 0.05) between overwintering months at 0-to-10 or 10-to-20-cm soil depths. These results suggest that H. glycines' ability to infect a subsequent soybean crop and develop to maturity is not diminished by nonhost crops or during the winter months.
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Abstract
OBJECTIVE To determine the activities and circumstances proximal to a welding related occupational eye injury, a hybrid narrative coding approach derived from two well developed classification systems was developed to categorize and describe the activity, initiating process, mechanism of injury, object and/or substance, and the use of protective eyewear from the narrative text data reported for each injury. METHODS Routinely collected workers' compensation claims over a one year period (2000) were analyzed from a large US insurance provider. An index term search algorithm of occupation, incident, and injury description fields identified 2209 potential welding related eye injury claims. After detailed review of these claims, 1353 welders and 822 non-welders were analyzed. RESULTS During 2000, eye(s) as the primary injured body part accounted for 5% (n = 26 413) of all compensation claims. Eye injuries accounted for 25% of all claims for welders. Subjects were mainly male (97.1%) and from manufacturing (70.4%), service (11.8%), or construction (8.4%) related industries. Most injuries were foreign body (71.7%) or burn (22.2%) and 17.6% were bilateral. Common activities include welding (31.9%) and/or grinding (22.5%). Being struck by an airborne object occurred in 56.3% of cases. Non-welders showed similar patterns except that burns (43.8%) were more frequent and more often initiated by another worker (13.9%). CONCLUSIONS Narrative injury text provides valuable data to supplement traditional epidemiologic analyses. Workers performing welding tasks or working nearby welders should be trained to recognize potential hazards and the effective use of proper safety equipment to prevent ocular injury.
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Affiliation(s)
- D A Lombardi
- Quantitative Analysis Unit, Liberty Mutual Research Institute for Safety, Hopkinton, MA, USA.
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Lincoln AE, Sorock GS, Courtney TK, Wellman HM, Smith GS, Amoroso PJ. Using narrative text and coded data to develop hazard scenarios for occupational injury interventions. Inj Prev 2004; 10:249-54. [PMID: 15314055 PMCID: PMC1730109 DOI: 10.1136/ip.2004.005181] [Citation(s) in RCA: 55] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Abstract
OBJECTIVE To determine whether narrative text in safety reports contains sufficient information regarding contributing factors and precipitating mechanisms to prioritize occupational back injury prevention strategies.Design, setting, subjects, and MAIN OUTCOME MEASURES Nine essential data elements were identified in narratives and coded sections of safety reports for each of 94 cases of back injuries to United States Army truck drivers reported to the United States Army Safety Center between 1987 and 1997. The essential elements of each case were used to reconstruct standardized event sequences. A taxonomy of the event sequences was then developed to identify common hazard scenarios and opportunities for primary interventions. RESULTS Coded data typically only identified five data elements (broad activity, task, event/exposure, nature of injury, and outcomes) while narratives provided additional elements (contributing factor, precipitating mechanism, primary source) essential for developing our taxonomy. Three hazard scenarios were associated with back injuries among Army truck drivers accounting for 83% of cases: struck by/against events during motor vehicle crashes; falls resulting from slips/trips or loss of balance; and overexertion from lifting activities. CONCLUSIONS Coded data from safety investigations lacked sufficient information to thoroughly characterize the injury event. However, the combination of existing narrative text (similar to that collected by many injury surveillance systems) and coded data enabled us to develop a more complete taxonomy of injury event characteristics and identify common hazard scenarios. This study demonstrates that narrative text can provide the additional information on contributing factors and precipitating mechanisms needed to target prevention strategies.
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Affiliation(s)
- A E Lincoln
- War-Related Illness and Injury Study Center, Washington DC Veterans Administration Medical Center, Department of Veterans Affairs, Washington, DC 20422, USA.
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Abstract
The treatment of para-esophageal hernia by the laparoscopic approach has been described by a number of authors. The lower morbidity of the laparoscopic approach compared with the open approach holds some attraction, however, reservations regarding the durability of laparoscopic repair exist. There is a paucity of objective follow-up data in the literature with regard to repair durability and symptomatic outcome. A review was undertaken of 94 patients over a 7 year period undergoing attempted laparoscopic repairs of para-esophageal hernia. Preoperative and operative data was collected and patients underwent postoperative interview and barium meal. Laparoscopic repair was successfully completed in 86 patients. Symptomatic reherniation occurred in 12% (10/86) of patients undergoing laparoscopic repair. These patients underwent open reoperative surgery. There were no symptomatic recurrences in patients undergoing initial open repair. Symptomatic outcome was assessed by interview in 78% (73/94) of patients at a median of 27 months (3-93 months) postoperatively. Ninety-seven percent (71/73) of patients were satisfied with their ultimate symptomatic outcome however, this group included seven patients who had required reoperative surgery for symptomatic recurrence and were therefore laparoscopic failures. In order to determine the asymptomatic recurrence rate patients were requested to undergo a barium meal. A further nine small asymptomatic recurrences were diagnosed in 42 patients having had laparoscopic repair. This represents an asymptomatic radiographic recurrence rate of 21%. Laparoscopic repair in this series was associated with a 12% symptomatic recurrence rate. The majority of patients with symptomatic recurrence underwent open reoperation with good results. Strategies for reducing recurrences should be examined in prospective series.
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Affiliation(s)
- G S Smith
- Department of Surgery, Concord Repatriation General Hospital, Hospital Road, Concord, NSW, Australia.
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Rallo MC, Shaffer WO, Standeven JW, Burdge RE, Davis BA, Smith GS. An inexpensive alternative approach to bone compression analyses. Int J Surg Investig 2003; 1:291-5. [PMID: 12774451] [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: 03/02/2023]
Abstract
A new method for testing the compression strength of vertebrae was developed and implemented using minimal resources and time expenditure. The device digitally measured and analyzed the torque and force necessary to load rat lumbar and thoracic vertebrae to failure. The system was calibrated using a series of known lead masses. Similar to other standardized force/compression and torque devices, this method has been shown to provide reliable and reproducible results. Furthermore, although vertebrae were the only specimens used to collect data in these initial studies, this measurement system could be altered quite easily to allow for a variety of test materials.
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Affiliation(s)
- M C Rallo
- Theodore Cooper Surgical Research Institute, Departments of General and Orthopedic Surgery, Saint Louis University Health Sciences Center, 1402 South Grand Blvd., St. Louis, MO 63104, USA
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Yim H, Kent MS, Huber DL, Satija S, Majewski J, Smith GS. Conformation of End-Tethered PNIPAM Chains in Water and in Acetone by Neutron Reflectivity. Macromolecules 2003. [DOI: 10.1021/ma021548o] [Citation(s) in RCA: 92] [Impact Index Per Article: 4.4] [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)
| | | | | | - S. Satija
- National Institute of Standards and Technology, Gaithersburg, Maryland
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Yim H, Kent MS, Matheson A, Stevens MJ, Ivkov R, Satija S, Majewski J, Smith GS. Adsorption of Sodium Poly(styrenesulfonate) to the Air Surface of Water by Neutron and X-ray Reflectivity and Surface Tension Measurements: Polymer Concentration Dependence. Macromolecules 2002. [DOI: 10.1021/ma0200468] [Citation(s) in RCA: 40] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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Baladas HG, Borody TJ, Smith GS, Dempsey MB, Richardson MA, Falk GL. Laparoscopic excision of a Brunner's gland hamartoma of the duodenum. Surg Endosc 2002; 16:1636. [PMID: 12196895 DOI: 10.1007/s004640040019] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/16/2002] [Accepted: 05/02/2002] [Indexed: 12/13/2022]
Abstract
Brunner's gland hamartoma (adenoma) was first described in 1876. It is a rare hamartomatous lesion, with only 100 cases reported in the world literature. Treatment has been by endoscopic snaring. Open surgical excision was reserved for cases where snaring had failed. We report a case of a Brunner's gland hamartoma (2.4 cm) that was successfully resected by laparoscopic techniques. Postoperative hospital stay was brief (2 days), and there were no complications. This is the second reported case to be resected laparoscopically.
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Affiliation(s)
- H G Baladas
- Department of Surgery, 001165 Alexandra Hospital, 4735222 Singapore
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Colgrove AL, Smith GS, Wrather JA, Heinz RD, Niblack TL. Lack of Predictable Race Shift in Heterodera glycines-Infested Field Plots. Plant Dis 2002; 86:1101-1108. [PMID: 30818503 DOI: 10.1094/pdis.2002.86.10.1101] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
Soybean cultivars with different sources of resistance to Heterodera glycines were grown at three locations initially infested with races 2, 3, and 6 in order to investigate H. glycines race shift in field populations. Each spring and fall, soil samples were taken from each plot and race tests were conducted to evaluate effects of cultivar and time of sampling. Field experiments were paired field plots rotated annually with corn since 1991. Cultivars included at the northern and central Missouri sites were Williams 82 (susceptible to H. glycines), Linford (PI 88788 source of resistance), MFA 9043 (Peking) replaced by Morsoy 9345 (Peking and PI 88788) from 1995 to 1997, and Jackson II (Peking + PI 88788) replaced by Asgrow 3431 (Peking and PI 88788) in 1996-97. Cultivars at the southern Missouri site were Essex or Hutcheson (susceptible to H. glycines), Forrest (Peking), Hartwig (PI 437654), and Rhodes (PI 88788 + Peking). In 1995, race tests were performed at four temperature regimes to determine temperature effects on race designations. Race shifts were not predictable based on the source of resistance of the soybean cultivar planted. Variability in female numbers on Lee 74 among tests caused changes in female indices (FI). Furthermore, race designations were influenced by the time of sampling and temperature at which the race tests were conducted. The variability of H. glycines populations in both field and greenhouse situations diminishes the value of race test results when making cultivar recommendations.
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Affiliation(s)
- A L Colgrove
- Department of Plant Microbiology and Pathology, University of Missouri, Columbia 65211
| | - G S Smith
- Department of Plant Microbiology and Pathology, University of Missouri, Columbia 65211
| | - J A Wrather
- Department of Plant Microbiology and Pathology, University of Missouri, Columbia 65211
| | - R D Heinz
- Department of Plant Microbiology and Pathology, University of Missouri, Columbia 65211
| | - T L Niblack
- Department of Plant Microbiology and Pathology, University of Missouri, Columbia 65211
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Jong L, Pearce EM, Kwei TK, Hamilton WA, Smith GS, Kwei GH. Hydrogen-bonded polymer blends: the influence of annealing on the interface composition of thin films. Macromolecules 2002. [DOI: 10.1021/ma00051a008] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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Russell TP, Menelle A, Hamilton WA, Smith GS, Satija SK, Majkrzak CF. Width of homopolymer interfaces in the presence of symmetric diblock copolymers. Macromolecules 2002. [DOI: 10.1021/ma00020a036] [Citation(s) in RCA: 80] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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Abstract
Esophageal leiomyoma are usually intramural and the most common minimally invasive approach is thoracoscopic excision leaving the mucosa intact. We report the case of a 58-year-old woman who underwent laparoscopic excision of a pedunculated esophageal leiomyoma.
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Affiliation(s)
- G S Smith
- Department of Upper Gastrointestinal and Laparoscopic Surgery, Concord Repatriation General Hospital, NSW, Australia.
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Koenen SV, Mecenas CA, Smith GS, Jenkins S, Nathanielsz PW. Effects of maternal betamethasone administration on fetal and maternal blood pressure and heart rate in the baboon at 0.7 of gestation. Am J Obstet Gynecol 2002; 186:812-7. [PMID: 11967513 DOI: 10.1067/mob.2002.121654] [Citation(s) in RCA: 81] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
OBJECTIVE We sought to determine the effects of the intramuscular maternal administration of betamethasone to the pregnant baboon at 0.7 of gestation on fetal blood pressure and heart rate. STUDY DESIGN We treated pregnant baboons at 0.7 of gestation with intramuscular betamethasone (n = 4), at a weight-adjusted dose equivalent to the daily dose administered to women in preterm labor or with saline solution (n = 5). Four injections were given at 12-hour intervals. Fetal and maternal blood pressure and heart rate were recorded continuously. Within-group differences and between-group differences were analyzed with repeated measures analysis of variance. RESULTS Fetal blood pressure increased significantly after betamethasone treatment. Fetal heart rate, maternal blood pressure, and heart rate did not change. CONCLUSION Exposure of the developing primate fetus to exogenous glucocorticoid at 0.7 of gestation elevates fetal blood pressure. These findings confirm and extend the observations in the fetal sheep. Further studies are needed to evaluate the mechanisms that are involved and possible long-term consequences of these cardiovascular effects of antenatal glucocorticoid exposure in the fetal primate.
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Affiliation(s)
- S V Koenen
- Department of Obstetrics, Neonatology and Gynecology, University Medical Centre, Utrect, The Netherlands
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Smith GS, Wolff AB, Kokoska ER, Galie KL, Boyce ML, Vogler GA, Miller TA. A simplified method for studying hypoxia and reoxygenation injury under in vitro conditions. Int J Surg Investig 2002; 1:73-80. [PMID: 11817340] [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] [Grants] [Subscribe] [Scholar Register] [Indexed: 02/23/2023]
Abstract
A hypoxia chamber was constructed which allowed for the sequential sampling and blood gas analysis of buffer bathing cells in culture which were subjected to graded periods of hypoxia. Following hypoxia, the human fetal small intestinal cells (CCL-241) were placed into a normoxic environment for the remainder of a 24 h study period. A cytotoxicity assay revealed significant mortality in cells subjected to hypoxia and reoxygenation, but not in those subjected to hypoxia alone. Analysis of lactate dehydrogenase release into buffer samples also indicated a greater cellular injury among cells exposed to hypoxia and reoxygenation. Additionally, levels of lipid peroxidation products were found to be significantly elevated in cells exposed to periods of hypoxia followed by reoxygenation, but not hypoxia alone, as measured by a thiobarbituric acid fluorometric assay. This suggests that lipid peroxidation mediated by oxygen-derived free radical species is the mechanism of injury in these cells. This study demonstrates that such a chamber provides a more precise way to monitor hypoxia and is a useful tool for studying hypoxia and reoxygenation under in vitro conditions.
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Affiliation(s)
- G S Smith
- Theodore Cooper Surgical Research Institute, Department of Surgery, Saint Louis University Health Sciences Center, MO 63104, USA
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Mapolie SF, Mavunkal IJ, Moss JR, Smith GS. The synthesis, characterization and polycondensation of metal-containing diols: crystal structure of [(?5-C5H5)(CO)2Fe(CH2)3O-{2,6-(CH2OH)2-4-CH3?C6H2}]. Appl Organomet Chem 2002. [DOI: 10.1002/aoc.301] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
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Retsos H, Terzis AF, Anastasiadis SH, Anastassopoulos DL, Toprakcioglu C, Theodorou DN, Smith GS, Menelle A, Gill RE, Hadziioannou G, Gallot Y. Mushrooms and Brushes in Thin Films of Diblock Copolymer/Homopolymer Mixtures. Macromolecules 2001. [DOI: 10.1021/ma011174j] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.0] [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)
- H. Retsos
- Foundation for Research and TechnologyHellas, Institute of Electronic Structure and Laser, P.O. Box 1527, 711 10 Heraklion, Crete, Greece; University of Crete, Physics Department, 710 03 Heraklion, Crete, Greece; University of Patras, Physics Department, 265 00 Rio Patras, Greece; University of Patras, Department of Chemical Engineering and Foundation for Research and TechnologyHellas, Institute of Chemical Engineering and High-Temperature Processes, 265 00 Rio Patras, Greece; Los Alamos National
| | - A. F. Terzis
- Foundation for Research and TechnologyHellas, Institute of Electronic Structure and Laser, P.O. Box 1527, 711 10 Heraklion, Crete, Greece; University of Crete, Physics Department, 710 03 Heraklion, Crete, Greece; University of Patras, Physics Department, 265 00 Rio Patras, Greece; University of Patras, Department of Chemical Engineering and Foundation for Research and TechnologyHellas, Institute of Chemical Engineering and High-Temperature Processes, 265 00 Rio Patras, Greece; Los Alamos National
| | - S. H. Anastasiadis
- Foundation for Research and TechnologyHellas, Institute of Electronic Structure and Laser, P.O. Box 1527, 711 10 Heraklion, Crete, Greece; University of Crete, Physics Department, 710 03 Heraklion, Crete, Greece; University of Patras, Physics Department, 265 00 Rio Patras, Greece; University of Patras, Department of Chemical Engineering and Foundation for Research and TechnologyHellas, Institute of Chemical Engineering and High-Temperature Processes, 265 00 Rio Patras, Greece; Los Alamos National
| | - D. L. Anastassopoulos
- Foundation for Research and TechnologyHellas, Institute of Electronic Structure and Laser, P.O. Box 1527, 711 10 Heraklion, Crete, Greece; University of Crete, Physics Department, 710 03 Heraklion, Crete, Greece; University of Patras, Physics Department, 265 00 Rio Patras, Greece; University of Patras, Department of Chemical Engineering and Foundation for Research and TechnologyHellas, Institute of Chemical Engineering and High-Temperature Processes, 265 00 Rio Patras, Greece; Los Alamos National
| | - C. Toprakcioglu
- Foundation for Research and TechnologyHellas, Institute of Electronic Structure and Laser, P.O. Box 1527, 711 10 Heraklion, Crete, Greece; University of Crete, Physics Department, 710 03 Heraklion, Crete, Greece; University of Patras, Physics Department, 265 00 Rio Patras, Greece; University of Patras, Department of Chemical Engineering and Foundation for Research and TechnologyHellas, Institute of Chemical Engineering and High-Temperature Processes, 265 00 Rio Patras, Greece; Los Alamos National
| | - D. N. Theodorou
- Foundation for Research and TechnologyHellas, Institute of Electronic Structure and Laser, P.O. Box 1527, 711 10 Heraklion, Crete, Greece; University of Crete, Physics Department, 710 03 Heraklion, Crete, Greece; University of Patras, Physics Department, 265 00 Rio Patras, Greece; University of Patras, Department of Chemical Engineering and Foundation for Research and TechnologyHellas, Institute of Chemical Engineering and High-Temperature Processes, 265 00 Rio Patras, Greece; Los Alamos National
| | - G. S. Smith
- Foundation for Research and TechnologyHellas, Institute of Electronic Structure and Laser, P.O. Box 1527, 711 10 Heraklion, Crete, Greece; University of Crete, Physics Department, 710 03 Heraklion, Crete, Greece; University of Patras, Physics Department, 265 00 Rio Patras, Greece; University of Patras, Department of Chemical Engineering and Foundation for Research and TechnologyHellas, Institute of Chemical Engineering and High-Temperature Processes, 265 00 Rio Patras, Greece; Los Alamos National
| | - A. Menelle
- Foundation for Research and TechnologyHellas, Institute of Electronic Structure and Laser, P.O. Box 1527, 711 10 Heraklion, Crete, Greece; University of Crete, Physics Department, 710 03 Heraklion, Crete, Greece; University of Patras, Physics Department, 265 00 Rio Patras, Greece; University of Patras, Department of Chemical Engineering and Foundation for Research and TechnologyHellas, Institute of Chemical Engineering and High-Temperature Processes, 265 00 Rio Patras, Greece; Los Alamos National
| | - R. E. Gill
- Foundation for Research and TechnologyHellas, Institute of Electronic Structure and Laser, P.O. Box 1527, 711 10 Heraklion, Crete, Greece; University of Crete, Physics Department, 710 03 Heraklion, Crete, Greece; University of Patras, Physics Department, 265 00 Rio Patras, Greece; University of Patras, Department of Chemical Engineering and Foundation for Research and TechnologyHellas, Institute of Chemical Engineering and High-Temperature Processes, 265 00 Rio Patras, Greece; Los Alamos National
| | - G. Hadziioannou
- Foundation for Research and TechnologyHellas, Institute of Electronic Structure and Laser, P.O. Box 1527, 711 10 Heraklion, Crete, Greece; University of Crete, Physics Department, 710 03 Heraklion, Crete, Greece; University of Patras, Physics Department, 265 00 Rio Patras, Greece; University of Patras, Department of Chemical Engineering and Foundation for Research and TechnologyHellas, Institute of Chemical Engineering and High-Temperature Processes, 265 00 Rio Patras, Greece; Los Alamos National
| | - Y. Gallot
- Foundation for Research and TechnologyHellas, Institute of Electronic Structure and Laser, P.O. Box 1527, 711 10 Heraklion, Crete, Greece; University of Crete, Physics Department, 710 03 Heraklion, Crete, Greece; University of Patras, Physics Department, 265 00 Rio Patras, Greece; University of Patras, Department of Chemical Engineering and Foundation for Research and TechnologyHellas, Institute of Chemical Engineering and High-Temperature Processes, 265 00 Rio Patras, Greece; Los Alamos National
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Smith GS, Keyl PM, Hadley JA, Bartley CL, Foss RD, Tolbert WG, McKnight J. Drinking and recreational boating fatalities: a population-based case-control study. JAMA 2001; 286:2974-80. [PMID: 11743838] [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] [Grants] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/22/2023]
Abstract
CONTEXT Alcohol is increasingly recognized as a factor in many boating fatalities, but the association between alcohol consumption and mortality among boaters has not been well quantified. OBJECTIVES To determine the association of alcohol use with passengers' and operators' estimated relative risk (RR) of dying while boating. DESIGN, SETTING, AND PARTICIPANTS Case-control study of recreational boating deaths among persons aged 18 years or older from 1990-1998 in Maryland and North Carolina (n = 221), compared with control interviews obtained from a multistage probability sample of boaters in each state from 1997-1999 (n = 3943). MAIN OUTCOME MEASURE Estimated RR of fatality associated with different levels of blood alcohol concentration (BAC) among boaters. RESULTS Compared with the referent of a BAC of 0, the estimated RR of death increased even with a BAC of 10 mg/dL (odds ratio [OR], 1.3; 95% confidence interval [CI], 1.2-1.4). The OR was 52.4 (95% CI, 25.9-106.1) at a BAC of 250 mg/dL. The estimated RR associated with alcohol use was similar for passengers and operators and did not vary by boat type or whether the boat was moving or stationary. CONCLUSIONS Drinking increases the RR of dying while boating, which becomes apparent at low levels of BAC and increases as BAC increases. Prevention efforts targeted only at those operating a boat are ignoring many boaters at high risk. Countermeasures that reduce drinking by all boat occupants are therefore more likely to effectively reduce boating fatalities.
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Affiliation(s)
- G S Smith
- Johns Hopkins Center for Injury Research and Policy, Baltimore, MD.
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Bell NS, Amoroso PJ, Yore MM, Senier L, Williams JO, Smith GS, Theriault A. Alcohol and other risk factors for drowning among male active duty U.S. army soldiers. Aviat Space Environ Med 2001; 72:1086-95. [PMID: 11763109 PMCID: PMC2141696] [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] [Subscribe] [Scholar Register] [Indexed: 02/23/2023]
Abstract
BACKGROUND Risk factors for drowning are largely undocumented among military populations. HYPOTHESIS Accident report narratives will provide important information about the role of alcohol use and other behaviors in drownings among active duty male U.S. Army soldiers. METHODS Using a case series design, we describe drowning deaths reported to the U.S. Army Safety Center (1980-1997), documenting associated demographic factors, alcohol use, and other risk-taking behaviors. RESULTS Drowning victims (n = 352) were disproportionately young, black, and single, with less time-in-service, and no college experience. Most drownings occurred off-duty (89%). Alcohol use was involved in at least 31% of the cases overall. Alcohol use was also associated with a 10-fold increase in reckless behavior (OR 9.6, 95% Cl 4.5-20.7) and was most common among drownings in Europe (OR = 4.3, 95% Cl 1.5-13.4). Most drownings occurred where no lifeguard was present (68%), but almost two-thirds occurred in the presence of others, with CPR initiated in less than one-third of these cases. Drownings involving minority victims were less likely to involve alcohol, but more likely to occur in unauthorized swimming areas. While most drownings did not involve violations of safety rules, over one-third of the cases involved some form of reckless behavior, particularly for those under age 21. CONCLUSIONS Intervention programs should be tailored to meet the needs of the demographic subgroups at highest risk since behavioral risk factors vary by race and age. CPR training and skills maintenance can improve survival rates. Narrative data are important for developing hypotheses and understanding risk factors for injuries.
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Abstract
Using a human gastric mucosal cell line, known as AGS cells, we determined the role that perturbations in intracellular Ca2+ concentration [Ca2+]i might play in cellular injury induced by various damaging agents. For deoxycholate (CD) and ethanol (EtOH) induced damage, a concentration related increase in [Ca2+]i was noted that preceded and closely paralleled the magnitude of injury. Thus, the higher the concentration of DC or EtOH, the more profound were the changes in [Ca2+]i and the resultant degree of cellular injury. Pretreatment with a low concentration of DC (50 microM; called a mild irritant) that was not damaging by itself attenuated injury induced by a damaging concentration (i.e. 250 microM) of DC, and appeared to elicit this protective action through mechanisms that resisted intracellular Ca2+ accumulation. Additional studies indicated that the mechanism of aspirin damage may be similar and that other protective agents such as prostaglandins and growth factors appear to mediate their protective properties through prevention of intracellular Ca2+ alterations. We propose that agents that prevent mucosal injury mediate this activity through a cellular response (involving active Ca2+ efflux) that subsequently provides a protective action by limiting the magnitude of intracellular Ca2+ accumulation.
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Affiliation(s)
- T A Miller
- Department of Surgery, Medical College of Virginia Campus at Virginia, Commonwealth University, Richmond 23298, USA
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Abstract
Using synchrotron grazing-incidence x-ray diffraction (GIXD) and reflectivity, the in-plane and out-of-plane structure of mixed ganglioside-phospholipid monolayers was investigated at the air-water interface. Mixed monolayers of 0, 5, 10, 20, and 100 mol% ganglioside GM(1) and the phospholipid dipalmitoylphosphatidylethanolamine (DPPE) were studied in the solid phase at 23 degrees C and a surface pressure of 45 mN/m. At these concentrations and conditions the two components do not phase-separate and no evidence for domain formation was observed. X-ray scattering measurements reveal that GM(1) is accommodated within the host DPPE monolayer and does not distort the hexagonal in-plane unit cell or out-of-plane two-dimensional (2-D) packing compared with a pure DPPE monolayer. The oligosaccharide headgroups were found to extend normally from the monolayer surface, and the incorporation of these glycolipids into DPPE monolayers did not affect hydrocarbon tail packing (fluidization or condensation of the hydrocarbon region). This is in contrast to previous investigations of lipopolymer-lipid mixtures, where the packing structure of phospholipid monolayers was greatly altered by the inclusion of lipids bearing hydrophilic polymer groups. Indeed, the lack of packing disruptions by the oligosaccharide groups indicates that protein-GM(1) interactions, including binding, insertion, chain fluidization, and domain formation (lipid rafts), can be studied in 2-D monolayers using scattering techniques.
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Affiliation(s)
- J Majewski
- Manuel Lujan Neutron Scattering Center, Los Alamos National Laboratory, Los Alamos, New Mexico 87545, USA
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