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Sinsky CA, Rule A, Cohen G, Arndt BG, Shanafelt TD, Sharp CD, Baxter SL, Tai-Seale M, Yan S, Chen Y, Adler-Milstein J, Hribar M. Metrics for assessing physician activity using electronic health record log data. J Am Med Inform Assoc 2021; 27:639-643. [PMID: 32027360 PMCID: PMC7075531 DOI: 10.1093/jamia/ocz223] [Citation(s) in RCA: 73] [Impact Index Per Article: 24.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2019] [Revised: 12/10/2019] [Accepted: 12/17/2019] [Indexed: 11/13/2022] Open
Abstract
Electronic health record (EHR) log data have shown promise in measuring physician time spent on clinical activities, contributing to deeper understanding and further optimization of the clinical environment. In this article, we propose 7 core measures of EHR use that reflect multiple dimensions of practice efficiency: total EHR time, work outside of work, time on documentation, time on prescriptions, inbox time, teamwork for orders, and an aspirational measure for the amount of undivided attention patients receive from their physicians during an encounter, undivided attention. We also illustrate sample use cases for these measures for multiple stakeholders. Finally, standardization of EHR log data measure specifications, as outlined here, will foster cross-study synthesis and comparative research.
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Affiliation(s)
- Christine A Sinsky
- Department of Medicine, American Medical Association, Chicago, Illinois, USA
| | - Adam Rule
- Department of Medical Informatics and Clinical Epidemiology, Oregon Health Sciences University, Oregon, USA
| | - Genna Cohen
- Department of Medicine, Mathematica, Washington, DC, USA
| | - Brian G Arndt
- Department of Family Medicine and Community Health, School of Medicine and Public Health, University of Wisconsin, Madison, Wisconsin, USA
| | - Tait D Shanafelt
- Division of Hematology, Department of Medicine, Stanford University, Stanford, California, USA
| | - Christopher D Sharp
- Division of Hematology, Department of Medicine, Stanford University, Stanford, California, USA.,Division of General Internal Medicine, Department of Medicine, Stanford University, Stanford, California, USA
| | - Sally L Baxter
- Department of Biomedical Informatics, University of California, San Diego, San Diego, California, USA.,Viterbi Family Department of Ophthalmology, Shiley Eye Institute, University of California, San Diego, San Diego, California, USA
| | - Ming Tai-Seale
- Department of Family Medicine and Public Health, University of California, San Diego, San Diego, California, USA
| | - Sherry Yan
- Department of Medicine, Sutter Health, Walnut Creek, California, USA
| | - You Chen
- Department of Biomedical Informatics, Vanderbilt University Medical Center, Nashville, Tennessee, USA
| | - Julia Adler-Milstein
- Department of Medicine, University of California, San Francisco, San Francisco, California, USA
| | - Michelle Hribar
- Department of Medical Informatics and Clinical Epidemiology, Oregon Health Sciences University, Oregon, USA
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Holmgren AJ, Downing NL, Bates DW, Shanafelt TD, Milstein A, Sharp CD, Cutler DM, Huckman RS, Schulman KA. Assessment of Electronic Health Record Use Between US and Non-US Health Systems. JAMA Intern Med 2021; 181:251-259. [PMID: 33315048 PMCID: PMC7737152 DOI: 10.1001/jamainternmed.2020.7071] [Citation(s) in RCA: 58] [Impact Index Per Article: 19.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/17/2020] [Accepted: 10/05/2020] [Indexed: 11/14/2022]
Abstract
Importance Understanding how the electronic health record (EHR) system changes clinician work, productivity, and well-being is critical. Little is known regarding global variation in patterns of use. Objective To provide insights into which EHR activities clinicians spend their time doing, the EHR tools they use, the system messages they receive, and the amount of time they spend using the EHR after hours. Design, Setting, and Participants This cross-sectional study analyzed the deidentified metadata of ambulatory care health systems in the US, Canada, Northern Europe, Western Europe, the Middle East, and Oceania from January 1, 2019, to August 31, 2019. All of these organizations used the EHR software from Epic Systems and represented most of Epic Systems's ambulatory customer base. The sample included all clinicians with scheduled patient appointments, such as physicians and advanced practice practitioners. Exposures Clinician EHR use was tracked by deidentified and aggregated metadata across a variety of clinical activities. Main Outcomes and Measures Descriptive statistics for clinician EHR use included time spent on clinical activities, note documentation (as measured by the percentage of characters in the note generated by automated or manual data entry source), messages received, and time spent after hours. Results A total of 371 health systems were included in the sample, of which 348 (93.8%) were located in the US and 23 (6.2%) were located in other countries. US clinicians spent more time per day actively using the EHR compared with non-US clinicians (mean time, 90.2 minutes vs 59.1 minutes; P < .001). In addition, US clinicians vs non-US clinicians spent significantly more time performing 4 clinical activities: notes (40.7 minutes vs 30.7 minutes; P < .001), orders (19.5 minutes vs 8.75 minutes; P < .001), in-basket messages (12.5 minutes vs 4.80 minutes; P < .001), and clinical review (17.6 minutes vs 14.8 minutes; P = .01). Clinicians in the US composed more automated note text than their non-US counterparts (77.5% vs 60.8% of note text; P < .001) and received statistically significantly more messages per day (33.8 vs 12.8; P < .001). Furthermore, US clinicians used the EHR for a longer time after hours, logging in 26.5 minutes per day vs 19.5 minutes per day for non-US clinicians (P = .01). The median US clinician spent as much time actively using the EHR per day (90.1 minutes) as a non-US clinician in the 99th percentile of active EHR use time per day (90.7 minutes) in the sample. These results persisted after controlling for organizational characteristics, including structure, type, size, and daily patient volume. Conclusions and Relevance This study found that US clinicians compared with their non-US counterparts spent substantially more time actively using the EHR for a wide range of clinical activities or tasks. This finding suggests that US clinicians have a greater EHR burden that may be associated with nontechnical factors, which policy makers and health system leaders should consider when addressing clinician wellness.
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Affiliation(s)
- A. Jay Holmgren
- Interfaculty Initiative in Health Policy, Harvard University, Cambridge, Massachusetts
- Harvard Business School, Boston, Massachusetts
| | - N. Lance Downing
- Department of Medicine, Stanford University, Stanford, California
- Clinical Excellence Research Center, Stanford University, Stanford, California
| | - David W. Bates
- Department of General Internal Medicine, Brigham & Women’s Hospital, Boston, Massachusetts
- Harvard Medical School, Boston, Massachusetts
| | - Tait D. Shanafelt
- Division of Hematology, Department of Medicine, Stanford University, Palo Alto, California
| | - Arnold Milstein
- Clinical Excellence Research Center, Stanford University, Stanford, California
| | | | - David M. Cutler
- Department of Economics, Harvard University, Cambridge, Massachusetts
| | | | - Kevin A. Schulman
- Department of Medicine, Stanford University, Stanford, California
- Clinical Excellence Research Center, Stanford University, Stanford, California
- Graduate School of Business, Stanford University, Stanford, California
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Affiliation(s)
- Yumi T DiAngi
- From Stanford University School of Medicine, Stanford Health Care, and Stanford Children's Health, Palo Alto, California; American Medical Association, Chicago, Illinois; and University HealthCare Alliance, Newark, California
| | - Tzielan C Lee
- From Stanford University School of Medicine, Stanford Health Care, and Stanford Children's Health, Palo Alto, California; American Medical Association, Chicago, Illinois; and University HealthCare Alliance, Newark, California
| | - Christine A Sinsky
- From Stanford University School of Medicine, Stanford Health Care, and Stanford Children's Health, Palo Alto, California; American Medical Association, Chicago, Illinois; and University HealthCare Alliance, Newark, California
| | - Bryan D Bohman
- From Stanford University School of Medicine, Stanford Health Care, and Stanford Children's Health, Palo Alto, California; American Medical Association, Chicago, Illinois; and University HealthCare Alliance, Newark, California
| | - Christopher D Sharp
- From Stanford University School of Medicine, Stanford Health Care, and Stanford Children's Health, Palo Alto, California; American Medical Association, Chicago, Illinois; and University HealthCare Alliance, Newark, California
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Affiliation(s)
- Pravene A Nath
- Information Technology Services, Stanford Health Care, Stanford, California2Division of Emergency Medicine, Department of Surgery, Stanford University School of Medicine, Stanford, California
| | - Christopher D Sharp
- Information Technology Services, Stanford Health Care, Stanford, California3Division of General Medical Disciplines, Department of Medicine, Stanford University School of Medicine, Stanford, California
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Glawe JD, Patrick DR, Huang M, Sharp CD, Barlow SC, Kevil CG. Genetic deficiency of Itgb2 or ItgaL prevents autoimmune diabetes through distinctly different mechanisms in NOD/LtJ mice. Diabetes 2009; 58:1292-301. [PMID: 19223596 PMCID: PMC2682677 DOI: 10.2337/db08-0804] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
OBJECTIVE Insulitis is an important pathological feature of autoimmune diabetes; however, mechanisms governing the recruitment of diabetogenic T-cells into pancreatic islets are poorly understood. Here, we determined the importance of leukocyte integrins beta(2)(Itgb2) and alphaL (ItgaL) in developing insulitis and frank diabetes. RESEARCH DESIGN AND METHODS Gene-targeted mutations of either Itgb2 or ItgaL were established on the NOD/LtJ mouse strain. Experiments were performed to measure insulitis and diabetes development. Studies were also performed measuring mutant T-cell adhesion to islet microvascular endothelial cells under hydrodynamic flow conditions. T-cell adhesion molecule profiles and adoptive transfer studies were also performed. RESULTS Genetic deficiency of either Itgb2 or ItgaL completely prevented the development of hyperglycemia and frank diabetes in NOD mice. Loss of Itgb2 or ItgaL prevented insulitis with Itgb2 deficiency conferring complete protection. In vitro hydrodynamic flow adhesion studies also showed that loss of Itgb2 completely abrogated T-cell adhesion. However, ItgaL deficiency did not alter NOD T-cell adhesion to or transmigration across islet endothelial cells. Adoptive transfer of ItgaL-deficient splenocytes into NOD/Rag-1 mice did not result in development of diabetes, suggesting a role for ItgaL in NOD/LtJ T-cell activation. CONCLUSIONS Together, these data demonstrate that genetic deficiency of Itgb2 or ItgaL confers protection against autoimmune diabetes through distinctly different mechanisms.
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Affiliation(s)
- John D. Glawe
- Department of Pathology, Louisiana State University Health Sciences Center Shreveport, Shreveport, Louisiana
| | - D. Ross Patrick
- Department of Pathology, Louisiana State University Health Sciences Center Shreveport, Shreveport, Louisiana
| | - Meng Huang
- Department of Pathology, Louisiana State University Health Sciences Center Shreveport, Shreveport, Louisiana
| | - Christopher D. Sharp
- Department of Pathology, Louisiana State University Health Sciences Center Shreveport, Shreveport, Louisiana
| | - Shayne C. Barlow
- Department of Pharmacology, Physiology, and Neuroscience, University of South Carolina School of Medicine, Columbia, South Carolina
| | - Christopher G. Kevil
- Department of Pathology, Louisiana State University Health Sciences Center Shreveport, Shreveport, Louisiana
- Corresponding author: Christopher Kevil,
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Sharp CD, Huang M, Glawe J, Patrick DR, Pardue S, Barlow SC, Kevil CG. Stromal cell-derived factor-1/CXCL12 stimulates chemorepulsion of NOD/LtJ T-cell adhesion to islet microvascular endothelium. Diabetes 2008; 57:102-12. [PMID: 17909096 DOI: 10.2337/db07-0494] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
OBJECTIVE Diabetogenic T-cell recruitment into pancreatic islets facilitates beta-cell destruction during autoimmune diabetes, yet specific mechanisms governing this process are poorly understood. The chemokine stromal cell-derived factor-1 (SDF-1) controls T-cell recruitment, and genetic polymorphisms of SDF-1 are associated with early development of type 1 diabetes. RESEARCH DESIGN AND METHODS Here, we examined the role of SDF-1 regulation of diabetogenic T-cell adhesion to islet microvascular endothelium. Islet microvascular endothelial cell monolayers were activated with tumor necrosis factor-alpha (TNF-alpha), subsequently coated with varying concentrations of SDF-1 (1-100 ng/ml), and assayed for T-cell/endothelial cell interactions under physiological flow conditions. RESULTS TNF-alpha significantly increased NOD/LtJ T-cell adhesion, which was completely blocked by SDF-1 in a dose-dependent manner, revealing a novel chemorepulsive effect. Conversely, SDF-1 enhanced C57BL/6J T-cell adhesion to TNF-alpha-activated islet endothelium, demonstrating that SDF-1 augments normal T-cell adhesion. SDF-1 chemorepulsion of NOD/LtJ T-cell adhesion was completely reversed by blocking G(i)alpha-protein-coupled receptor activity with pertussis toxin. CXCR4 protein expression was significantly decreased in NOD/LtJ T-cells, and inhibition of CXCR4 activity significantly reversed SDF-1 chemorepulsive effects. Interestingly, SDF-1 treatment significantly abolished T-cell resistance to shear-mediated detachment without altering adhesion molecule expression, thus demonstrating decreased integrin affinity and avidity. CONCLUSIONS In this study, we have identified a previously unknown novel function of SDF-1 in negatively regulating NOD/LtJ diabetogenic T-cell adhesion, which may be important in regulating diabetogenic T-cell recruitment into islets.
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Affiliation(s)
- Christopher D Sharp
- Department of Pathology, Louisiana State University Health Sciences Center-Shreveport, 1501 Kings Hwy., Shreveport, LA 71130-3932, USA
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Sharp CD, Glawe JD, Huang M, Barlow SC, Kevil CG. Chemokine repulsion of autoimmune T cell adhesion. FASEB J 2006. [DOI: 10.1096/fasebj.20.4.a202-c] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Affiliation(s)
| | | | | | - Shayne C Barlow
- Molecular and Cellular PhysiologyLSU Health Sciences Center‐Shreveport1501 Kings HwyShreveportLA71130
| | - Christopher G Kevil
- Pathology
- Molecular and Cellular PhysiologyLSU Health Sciences Center‐Shreveport1501 Kings HwyShreveportLA71130
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Sharp CD, Houghton J, Elrod JW, Warren A, Jackson TH, Jawahar A, Nanda A, Minagar A, Alexander JS. N-methyl-d-aspartate receptor activation in human cerebral endothelium promotes intracellular oxidant stress. Am J Physiol Heart Circ Physiol 2005; 288:H1893-9. [PMID: 15576430 DOI: 10.1152/ajpheart.01110.2003] [Citation(s) in RCA: 64] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Cerebral endothelial cells in the rat, pig, and, most recently, human have been shown to express several types of receptors specific for glutamate. High levels of glutamate disrupt the cerebral endothelial barrier via activation of N-methyl-d-aspartate (NMDA) receptors. We have previously suggested that this glutamate-induced barrier dysfunction was oxidant dependent. Here, we provide evidence that human cerebral endothelial cells respond to glutamate by generating an intracellular oxidant stress via NMDA receptor activation. Cerebral endothelial cells loaded with the oxidant-sensitive probe dihydrorhodamine were used to measure intracellular reactive oxygen species (ROS) formation in response to glutamate receptor agonists, antagonists, and second message blockers. Glutamate (1 mM) significantly increased ROS formation compared with sham controls (30 min). This ROS response was significantly reduced by 1) MK-801, a noncompetitive NMDA receptor antagonist; 2) 8-( N, N-diethylamino)- n-octyl-3,4,5-trimethoxybenzoate, an intracellular Ca2+antagonist; 3) LaCl3, an extracellular Ca2+channel blocker; 4) diphenyleiodonium, a heme-ferryl-containing protein inhibitor; 5) itraconazole, a cytochrome P-450 3A4 inhibitor; and 6) cyclosporine A, which prevents mitochondrial membrane pore transition required for mitochondrial-dependent ROS generation. Our results suggest that the cerebral endothelial barrier dysfunction seen in response to glutamate is Ca2+dependent and may require several intracellular signaling events mediated by oxidants derived from reduced nicotinamide adenine dinucleotide oxidase, cytochrome P-450, and the mitochondria.
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Affiliation(s)
- Christopher D Sharp
- Dept. of Molecular and Cellular Physiology, Louisiana State University Health Sciences Center, 1501 Kings Highway, Shreveport, LA 71130-3932, USA
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Xiao F, Pardue S, Arnold T, Carden D, Alexander JS, Monroe J, Sharp CD, Turnage R, Conrad S. Effect of ifenprodil, a polyamine site NMDA receptor antagonist, on brain edema formation following asphyxial cardiac arrest in rats. Resuscitation 2004; 61:209-19. [PMID: 15135198 DOI: 10.1016/j.resuscitation.2003.12.022] [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] [Received: 10/08/2003] [Revised: 12/18/2003] [Accepted: 12/18/2003] [Indexed: 12/31/2022]
Abstract
OBJECTIVE Brain edema occurs in experimental and clinical cardiac arrest (CA) and is predictive of a poor neurological outcome. N-Methyl--aspartate (NMDA) receptors contribute to brain edema elicited by focal cerebral ischemia/reperfusion (I/R). Ifenprodil, a NMDA receptor antagonist, attenuates brain edema and injury size in rats after focal cerebral I/R. We assessed the hypothesis that ifenprodil reduces CA-elicited brain edema. METHODS Eighteen male Sprague-Dawley rats were assigned to group 1 (normal control, n=6), group 2 (placebo-treated CA, n=6), or group 3 (ifenprodil-treated CA, n=6). CA was induced by 8 min of asphyxiation and the animals were resuscitated with cardiopulmonary resuscitation (CPR), ventilation, epinephrine (adrenaline), and sodium bicarbonate (NaHCO3). Ifenprodil of 10 mg/kg or a placebo vehicle was given intraperitoneally 5 min before CA. Brain edema was determined by brain wet-to-dry weight ratio at 1 h after resuscitation. RESULTS There were no differences between groups 2 and 3 in all physiological variables at baseline. Time from asphyxiation to CA was 201.5 +/- 7.5 s in group 2 and 160.7 +/- 10.4 s in group 3 (P<0.001). Resuscitation time was 68.2 +/- 13.3 s in group 2 and 92.8 +/- 18.2 s in group 3 (P<0.05). Ifenprodil decreased mean arterial pressure (MAP) before asphyxiation, from 128 +/- 7 in group 2 to 82 +/- 15 mmHg in group 3 (P<0.001), and negated immediate post-resuscitation hypertension. Brain wet-to-dry weight ratio was 5.64 +/- 0.44 in group 1, 7.34 +/- 0.95 in group 2 (P<0.01 versus group 1), and 5.93 +/- 0.40 in group 3 (P<0.05 versus group 2). CONCLUSIONS Ifenprodil reduces CA-elicited brain edema. In addition, we observed significant hemodynamic changes caused by ifenprodil.
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Affiliation(s)
- Feng Xiao
- Department of Emergency Medicine, Louisiana State University Health Sciences Center in Shreveport, 1501 Kings Highway, Shreveport, LA 71130, USA.
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Jawahar A, Jawahar LL, Nanda A, Sharp CD, Warren A, Elrod JW, Jennings M, Alexander JS, Minagar A. Stereotactic radiosurgery using the Leksell Gamma knife: current trends and future directives. FRONT BIOSCI-LANDMRK 2004; 9:932-8. [PMID: 14766419 DOI: 10.2741/1294] [Citation(s) in RCA: 9] [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] [Indexed: 11/22/2022]
Abstract
Stereotactic radiosurgery is the extremely precise administration of a radiation dosage in three-dimensional space to treat an increasingly broad spectrum of intracranial and skull-base lesions. 455 patients with various indications were treated using the 201 Source Co-60 Leksell Model "B" Gamma Knife(r) at Louisiana State University Health Sciences Center in Shreveport, Louisiana. 273 (60.2%) patients received radiosurgery as the first line of treatment for their disease. The mean Karnofsky Performance Score (KPS) of the patients was 70. Cerebral metastases were the main indications for radiosurgery at our center accounting for 27% of the patients, while meningioma, AVM, trigeminal neuralgia, movement disorders, and primary CNS malignant tumors were the other indications. Our institutional experience and results indicate that low incidence of complications coupled with a high tumor control rate makes Gamma Knife stereotactic radiosurgery a viable option for patients who must undergo neurosurgery. As the Gamma Knife continues to prove itself as a first-line treatment of many complex brain disorders, new indications for this technology will continue to emerge, further broadening the scope of patient care.
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Affiliation(s)
- Ajay Jawahar
- Department of Neurosurgery, Louisiana State University Health Sciences Center in Shreveport, Shreveport, Louisiana 71130, USA.
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Sharp CD, Hines I, Houghton J, Warren A, Jackson TH, Jawahar A, Nanda A, Elrod JW, Long A, Chi A, Minagar A, Alexander JS. Glutamate causes a loss in human cerebral endothelial barrier integrity through activation of NMDA receptor. Am J Physiol Heart Circ Physiol 2003; 285:H2592-8. [PMID: 12893641 DOI: 10.1152/ajpheart.00520.2003] [Citation(s) in RCA: 130] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
l-Glutamate is a major excitatory neurotransmitter that binds ionotropic and metabotropic glutamate receptors. Cerebral endothelial cells from many species have been shown to express several forms of glutamate receptors; however, human cerebral endothelial cells have not been shown to express either the N-methyl-D-aspartate (NMDA) receptor message or protein. This study provides evidence that human cerebral endothelial cells express the message and protein for NMDA receptors. Human cerebral endothelial cell monolayer electrical resistance changes in response to glutamate receptor agonists, antagonists, and second message blockers were tested. RT-PCR and Western blot analysis were used to demonstrate the presence of the NMDA receptor. Glutamate and NMDA (1 mM) caused a significant decrease in electrical resistance compared with sham control at 2 h postexposure; this response could be blocked significantly by MK-801 (an NMDA antagonist), 8-(N,N-diethylamino)-n-octyl-3,4,5-trimethyoxybenzoate (an intracellular Ca2+ antagonist), and N-acetyl-L-cystein (an antioxidant). Trans(+/-)-1-amino-1,3-cyclopentanedicarboxylic acid, a metabotropic receptor agonist (1 mM), did not significantly decrease electrical resistance. Our results are consistent with a model where glutamate, at excitotoxic levels, may lead to a breakdown in the blood brain barrier via activation of NMDA receptors.
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Affiliation(s)
- Christopher D Sharp
- Department of Molecular and Cellular Physiology, Louisiana State University Health Sciences Center, 1501 Kings Hwy., Shreveport, LA 71130-3932, USA
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Sharp CD, Fowler M, Jackson TH, Houghton J, Warren A, Nanda A, Chandler I, Cappell B, Long A, Minagar A, Alexander JS. Human neuroepithelial cells express NMDA receptors. BMC Neurosci 2003; 4:28. [PMID: 14614784 PMCID: PMC293342 DOI: 10.1186/1471-2202-4-28] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2003] [Accepted: 11/13/2003] [Indexed: 11/16/2022] Open
Abstract
L-glutamate, an excitatory neurotransmitter, binds to both ionotropic and metabotropic glutamate receptors. In certain parts of the brain the BBB contains two normally impermeable barriers: 1) cerebral endothelial barrier and 2) cerebral epithelial barrier. Human cerebral endothelial cells express NMDA receptors; however, to date, human cerebral epithelial cells (neuroepithelial cells) have not been shown to express NMDA receptor message or protein. In this study, human hypothalamic sections were examined for NMDA receptors (NMDAR) expression via immunohistochemistry and murine neuroepithelial cell line (V1) were examined for NMDAR via RT-PCR and Western analysis. We found that human cerebral epithelium express protein and cultured mouse neuroepithelial cells express both mRNA and protein for the NMDA receptor. These findings may have important consequences for neuroepithelial responses during excitotoxicity and in disease.
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Affiliation(s)
- Christopher D Sharp
- Department of Molecular and Cellular Physiology, LSU Health Sciences Center, Shreveport, LA, USA
| | - M Fowler
- Department of Pathology, LSU Health Sciences Center, Shreveport, LA, USA
| | - TH Jackson
- Department of Molecular and Cellular Physiology, LSU Health Sciences Center, Shreveport, LA, USA
| | - J Houghton
- Department of Molecular and Cellular Physiology, LSU Health Sciences Center, Shreveport, LA, USA
| | - A Warren
- Department of Molecular and Cellular Physiology, LSU Health Sciences Center, Shreveport, LA, USA
| | - A Nanda
- Department of Neurosurgery, LSU Health Sciences Center, Shreveport, LA, USA
| | - I Chandler
- Department of Molecular and Cellular Physiology, LSU Health Sciences Center, Shreveport, LA, USA
| | - B Cappell
- Department of Molecular and Cellular Physiology, LSU Health Sciences Center, Shreveport, LA, USA
| | - A Long
- Department of Molecular and Cellular Physiology, LSU Health Sciences Center, Shreveport, LA, USA
| | - A Minagar
- Department of Neurology, LSU Health Sciences Center, Shreveport, LA, USA
| | - JS Alexander
- Department of Molecular and Cellular Physiology, LSU Health Sciences Center, Shreveport, LA, USA
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Sharp CD, Jawahar A, Warren AC, Elrod JW, Nanda A, Alexander JS. Gamma knife irradiation increases cerebral endothelial expression of intercellular adhesion molecule 1 and E-selectin. Neurosurgery 2003; 53:154-60; discussion 160-1. [PMID: 12823884 DOI: 10.1227/01.neu.0000068840.84484.da] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2002] [Accepted: 01/28/2003] [Indexed: 11/19/2022] Open
Abstract
OBJECTIVE Alterations in multiple functions of the microvasculature occur in response to gamma irradiation and are thought to contribute to radiation-induced end organ damage by inducing inflammatory responses, particularly leukocyte infiltration into the affected area. Endothelial cell adhesion molecules (ECAMs) mediate leukocyte adhesion and migration. Here, we validate a method to study the effect of Leksell gamma knife stereotactic radiosurgery on the expression of ECAMs on human cerebral endothelium at 0, 24, 48, and 72 hours after irradiation. METHODS A human brain endothelial cell line (IHEC) was cultured on 12-mm coverslips and subjected to 50 Gy of collimated gamma irradiation with the Leksell gamma knife (Elekta Instruments, Inc., Atlanta, GA). Lactate dehydrogenase release was measured at 24, 48, and 72 hours after irradiation and caspase-3 at 24, 48, 72, 96, and 120 hours. ECAM expression was measured at postirradiation intervals of 0, 24, 48, and 72 hours by cell enzyme-linked immunoabsorbent assay. We used a cell irradiator composed of two chambers. The upper chamber holds the coverslips firmly in place while they are immersed in media. The lower chamber is connected to a peristaltic pump, which pumps water into the chamber and maintains the media in the upper chamber at 37 degrees C through convection. RESULTS None of the ECAMs tested was significantly elevated compared with the control basally. Twenty-four hours after irradiation, intercellular adhesion molecule 1 was significantly elevated on brain endothelial cells but there was no significant elevation of E-selectin. Vascular cell adhesion molecule 1 was increased slightly but not significantly and decreased at 48 hours. At 72 hours, E-selectin expression was significantly increased; intercellular adhesion molecule 1 and vascular cell adhesion molecule 1 were not altered relative to sham controls. CONCLUSION Increased ECAM expression and lactate dehydrogenase release support the idea that the cerebral microvasculature undergoes an inflammatory response after Leksell gamma knife stereotactic radiosurgery.
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Affiliation(s)
- Christopher D Sharp
- Department of Molecular and Cellular Physiology, Louisiana State University Health Sciences Center, Shreveport, Louisiana 71130, USA
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Abstract
Platelets play a major role in thrombosis and hemostasis by binding the sub-endothelial matrix at sites of injury, but also participate in vascular pathologies such as atherosclerosis. Recently, junctional proteins like PECAM-I and JAM-family members have been recovered from platelets, therefore we examined what other junctional molecules may be present in platelets. We observed immunoreactivity for APC (147 kD), beta-catenin (92 kD), E-cadherin (120 and 84 kD) and occludin (70-85 kD) by western blotting. Additionally, beta-catenin, pan-reactive cadherins, E-cadherin and occludin were seen to partition with the triton insoluble cytoskeleton in platelets. These proteins were also found in a megakaryocyte (platelet precursor) line, MEG-01. Our data suggest that conventional junctional molecules are expressed in platelets and could possibly participate in aggregation, clot formation and wound healing.
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Affiliation(s)
- J W Elrod
- Department of Molecular and Cellular Physiology, Louisiana State University Medical Center, Shreveport, Louisiana 71130-3932, USA
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Balamraju Y, Sharp CD, Gammill W, Manuel N, Pratt LM. Mixed aggregates of lithium tetramethylpiperidide with butyllithium: Stereoselectivity of ketone enolization. Tetrahedron 1998. [DOI: 10.1016/s0040-4020(98)00402-5] [Citation(s) in RCA: 23] [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: 11/15/2022]
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