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McNally JS, Sakata A, Alexander MD, Dewitt LD, Sonnen JA, Menacho ST, Stoddard GJ, Kim SE, de Havenon AH. Vessel Wall Enhancement on Black-Blood MRI Predicts Acute and Future Stroke in Cerebral Amyloid Angiopathy. AJNR Am J Neuroradiol 2021; 42:1038-1045. [PMID: 33737266 PMCID: PMC8191668 DOI: 10.3174/ajnr.a7047] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [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] [Received: 10/12/2020] [Accepted: 12/11/2020] [Indexed: 11/07/2022]
Abstract
BACKGROUND AND PURPOSE Cerebral amyloid angiopathy (CAA) is a known risk factor for ischemic stroke though angiographic imaging is often negative. Our goal was to determine the relationship between vessel wall enhancement (VWE) in acute and future ischemic stroke in CAA patients. MATERIALS AND METHODS This was a retrospective study of patients with new-onset neurologic symptoms undergoing 3T vessel wall MR imaging from 2015 to 2019. Vessel wall enhancement was detected on pre- and postcontrast flow-suppressed 3D T1WI. Interrater agreement was evaluated in cerebral amyloid angiopathy-positive and age-matched negative participants using a prevalence- and bias-adjusted kappa analysis. In patients with cerebral amyloid angiopathy, multivariable Poisson and Cox regression were used to determine the association of vessel wall enhancement with acute and future ischemic stroke, respectively, using backward elimination of confounders to P < .20. RESULTS Fifty patients with cerebral amyloid angiopathy underwent vessel wall MR imaging, including 35/50 (70.0%) with ischemic stroke and 29/50 (58.0%) with vessel wall enhancement. Prevalence- and bias-corrected kappa was 0.82 (95% CI, 0.71-0.93). The final regression model for acute ischemic stroke included vessel wall enhancement (prevalence ratio = 1.5; 95% CI, 1.1-2.2; P = .022), age (prevalence ratio = 1.02; 95% CI, 1.0-1.05; P = .036), time between symptoms and MR imaging (prevalence ratio = 0.9; 95% CI, 0.8-0.9; P < .001), and smoking (prevalence ratio = 0.7; 95% CI, 0.5-1.0; P = .042) with c-statistic = 0.92 (95% CI, 0.84-0.99). Future ischemic stroke incidence with cerebral amyloid angiopathy was 49.7% (95% CI, 34.5%-67.2%) per year over a total time at risk of 37.5 person-years. Vessel wall enhancement-positive patients with cerebral amyloid angiopathy demonstrated significantly shorter stroke-free survival with 63.9% (95% CI, 43.2%-84.0%) versus 32.2% (95% CI, 14.4%-62.3%) ischemic strokes per year, chi-square = 4.9, P = .027. The final model for future ischemic stroke had a c-statistic of 0.70 and included initial ischemic stroke (hazard ratio = 3.4; 95% CI, 1.0-12.0; P = .053) and vessel wall enhancement (hazard ratio = 2.5; 95% CI, 0.9-7.0; P = .080). CONCLUSIONS Vessel wall enhancement is associated with both acute and future stroke in patients with cerebral amyloid angiopathy.
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Affiliation(s)
- J S McNally
- From the Department of Radiology (J.S.M., A.S., M.D.A., S.-E.K.), Utah Center for Advanced Imaging Research, Utah
| | - A Sakata
- From the Department of Radiology (J.S.M., A.S., M.D.A., S.-E.K.), Utah Center for Advanced Imaging Research, Utah
| | - M D Alexander
- From the Department of Radiology (J.S.M., A.S., M.D.A., S.-E.K.), Utah Center for Advanced Imaging Research, Utah
| | - L D Dewitt
- Department of Pathology (J.A.S.), University of Utah, Salt Lake City, Utah
| | - J A Sonnen
- Department of Pathology (J.A.S.), University of Utah, Salt Lake City, Utah
| | - S T Menacho
- Department of Neurosurgery (S.T.M.), University of Utah, Salt Lake City, Utah
| | - G J Stoddard
- Department of Internal Medicine (G.J.S.), University of Utah, Salt Lake City, Utah
| | - S-E Kim
- From the Department of Radiology (J.S.M., A.S., M.D.A., S.-E.K.), Utah Center for Advanced Imaging Research, Utah
| | - A H de Havenon
- Department of Neurology (L.D.D., A.H.d.H.), University of Utah, Salt Lake City, Utah
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Alexander MD. The future of digital dermatology. Clin Exp Dermatol 2021; 46:740-741. [PMID: 33314294 DOI: 10.1111/ced.14536] [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] [Received: 12/07/2020] [Accepted: 12/09/2020] [Indexed: 12/01/2022]
Affiliation(s)
- M D Alexander
- Department of Dermatology, Royal Victoria Infirmary, Newcastle upon Tyne, NE1 4LP, UK
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Vella M, Alexander MD, Mabray MC, Cooke DL, Amans MR, Glastonbury CM, Kim H, Wilson MW, Langston DE, Conrad MB, Hetts SW. Comparison of MRI, MRA, and DSA for Detection of Cerebral Arteriovenous Malformations in Hereditary Hemorrhagic Telangiectasia. AJNR Am J Neuroradiol 2020; 41:969-975. [PMID: 32381546 DOI: 10.3174/ajnr.a6549] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2020] [Accepted: 03/26/2020] [Indexed: 11/07/2022]
Abstract
BACKGROUND AND PURPOSE Patients with hereditary hemorrhagic telangiectasia (HHT) have a high prevalence of brain vascular malformations, putting them at risk for brain hemorrhage and other complications. Our aim was to evaluate the relative utility of MR imaging and MRA compared with DSA in detecting cerebral AVMs in the HHT population. MATERIALS AND METHODS Of 343 consecutive patients evaluated at the University of California, San Francisco HTT Center of Excellence, 63 met the study inclusion criteria: definite or probable hereditary hemorrhagic telangiectasia defined by meeting at least 2 Curacao criteria or positive genetic testing, as well as having at least 1 brain MR imaging and 1 DSA. MRIs were retrospectively reviewed, and the number of AVMs identified was compared with the number of AVMs identified on DSA. RESULTS Of 63 patients, 45 (71%) had AVMs on DSA with a total of 92 AVMs identified. Of those, 24 (26%) were seen only on DSA; 68 (74%), on both DSA and MR imaging; and 5 additional lesions were seen only on MR imaging. Of the 92 lesions confirmed on DSA, 49 (53.3%) were seen on the 3D-T1 postgadolinium sequence, 52 (56.5%) were seen on the 2D-T1 postgadolinium sequence, 35 (38.0%) were seen on the SWI sequence, 24 (26.1%) were seen on T2 sequence, and 25 (27.2%) were seen on MRA. The sensitivity and specificity of MR imaging as a whole in detecting AVMs then confirmed on DSA were 80.0% and 94.4%, respectively, and the positive and negative predictive values were 97.3% and 65.4%, respectively. CONCLUSIONS This study reinforces the use of MR imaging as a primary screening tool for cerebral AVMs in patients with hereditary hemorrhagic telangiectasia and suggests that 3D-T1 postgadolinium and 2D-T1 postgadolinium performed at 3T are the highest yield sequences.
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Affiliation(s)
- M Vella
- From the Departments of Radiology and Biomedical Imaging (M.V.)
| | - M D Alexander
- Department of Radiology, Division of Interventional Neuroradiology (M.D.A.), University of Utah, Salt Lake City, Utah
| | - M C Mabray
- Department of Radiology, Division of Neuroradiology (M.C.M.), University of New Mexico, Albuquerque, New Mexico
| | - D L Cooke
- Division of Neurointerventional Radiology (D.L.C., M.R.A., D.E.L., S.W.H.)
| | - M R Amans
- Division of Neurointerventional Radiology (D.L.C., M.R.A., D.E.L., S.W.H.)
| | | | - H Kim
- Hereditary Hemorrhagic Telangiectasia Center of Excellence (H.K., D.E.L., M.B.C., S.W.H.).,Anesthesia and Perioperative Care (H.K.), University of California, San Francisco, San Francisco, California
| | - M W Wilson
- Division of Interventional Radiology (M.W.W., M.B.C.)
| | - D E Langston
- Division of Neurointerventional Radiology (D.L.C., M.R.A., D.E.L., S.W.H.).,Hereditary Hemorrhagic Telangiectasia Center of Excellence (H.K., D.E.L., M.B.C., S.W.H.)
| | - M B Conrad
- Division of Interventional Radiology (M.W.W., M.B.C.).,Hereditary Hemorrhagic Telangiectasia Center of Excellence (H.K., D.E.L., M.B.C., S.W.H.)
| | - S W Hetts
- Division of Neurointerventional Radiology (D.L.C., M.R.A., D.E.L., S.W.H.) .,Hereditary Hemorrhagic Telangiectasia Center of Excellence (H.K., D.E.L., M.B.C., S.W.H.)
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Alexander MD, de Havenon A, Mossa-Basha M, McNally JS. How Far Can We Take Vessel Wall MRI for Intracranial Atherosclerosis? The Tissue is Still the Issue. AJNR Am J Neuroradiol 2020; 41:E30-E31. [PMID: 32354713 DOI: 10.3174/ajnr.a6501] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Affiliation(s)
- M D Alexander
- Departments of Radiology and Imaging Sciences and Neurosurgery
| | - A de Havenon
- Department of NeurologyUniversity of UtahSalt Lake City, Utah
| | - M Mossa-Basha
- Department of RadiologyUniversity of WashingtonSeattle, Washington
| | - J S McNally
- Departments of Radiology and Imaging SciencesUniversity of UtahSalt Lake City, Utah
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5
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Knox JA, Alexander MD, McCoy DB, Murph DC, Hinckley PJ, Ch'ang JC, Dowd CF, Halbach VV, Higashida RT, Amans MR, Hetts SW, Cooke DL. Impact of Aortic Arch Anatomy on Technical Performance and Clinical Outcomes in Patients with Acute Ischemic Stroke. AJNR Am J Neuroradiol 2020; 41:268-273. [PMID: 32001445 DOI: 10.3174/ajnr.a6422] [Citation(s) in RCA: 19] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2019] [Accepted: 12/11/2019] [Indexed: 11/07/2022]
Abstract
BACKGROUND AND PURPOSE Arterial access is a technical consideration of mechanical thrombectomy that may affect procedural time, but few studies exist detailing the relationship of anatomy to procedural times and patient outcomes. We sought to investigate the respective impact of aortic arch and carotid artery anatomy on endovascular procedural times in patients with large-vessel occlusion. MATERIALS AND METHODS We retrospectively reviewed imaging and medical records of 207 patients from 2 academic institutions who underwent mechanical thrombectomy for anterior circulation large-vessel occlusion from January 2015 to July 2018. Preintervention CTAs were assessed to measure features of the aortic arch and ipsilateral great vessel anatomy. These included the cranial-to-caudal distance from the origin of the innominate artery to the top of the aortic arch and the takeoff angle of the respective great vessel from the arch. mRS scores were calculated from rehabilitation and other outpatient documentation. We performed bootstrap, stepwise regressions to model groin puncture to reperfusion time and binary mRS outcomes (good outcome, mRS ≤ 2). RESULTS From our linear regression for groin puncture to reperfusion time, we found a significant association of the great vessel takeoff angle (P = .002) and caudal distance from the origin of the innominate artery to the top of the aortic arch (P = .05). Regression analysis for the binary mRS revealed a significant association with groin puncture to reperfusion time (P < .001). CONCLUSIONS These results demonstrate that patients with larger takeoff angles and extreme aortic arches have an association with longer procedural times as approached from transfemoral access routes.
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Affiliation(s)
- J A Knox
- From the Departments of Radiology (J.A.K., D.B.M., D.C.M., P.J.H., C.F.D., V.V.H., R.T.H., M.R.A., S.W.H., D.L.C.) and
| | - M D Alexander
- Neurology (J.C.C.), University of California, San Francisco, San Francisco, California
| | - D B McCoy
- From the Departments of Radiology (J.A.K., D.B.M., D.C.M., P.J.H., C.F.D., V.V.H., R.T.H., M.R.A., S.W.H., D.L.C.) and
| | - D C Murph
- From the Departments of Radiology (J.A.K., D.B.M., D.C.M., P.J.H., C.F.D., V.V.H., R.T.H., M.R.A., S.W.H., D.L.C.) and
| | - P J Hinckley
- From the Departments of Radiology (J.A.K., D.B.M., D.C.M., P.J.H., C.F.D., V.V.H., R.T.H., M.R.A., S.W.H., D.L.C.) and
| | - J C Ch'ang
- Department of Radiology (M.D.A.), University of Utah, Salt Lake City, Utah
| | - C F Dowd
- From the Departments of Radiology (J.A.K., D.B.M., D.C.M., P.J.H., C.F.D., V.V.H., R.T.H., M.R.A., S.W.H., D.L.C.) and
| | - V V Halbach
- From the Departments of Radiology (J.A.K., D.B.M., D.C.M., P.J.H., C.F.D., V.V.H., R.T.H., M.R.A., S.W.H., D.L.C.) and
| | - R T Higashida
- From the Departments of Radiology (J.A.K., D.B.M., D.C.M., P.J.H., C.F.D., V.V.H., R.T.H., M.R.A., S.W.H., D.L.C.) and
| | - M R Amans
- From the Departments of Radiology (J.A.K., D.B.M., D.C.M., P.J.H., C.F.D., V.V.H., R.T.H., M.R.A., S.W.H., D.L.C.) and
| | - S W Hetts
- From the Departments of Radiology (J.A.K., D.B.M., D.C.M., P.J.H., C.F.D., V.V.H., R.T.H., M.R.A., S.W.H., D.L.C.) and
| | - D L Cooke
- From the Departments of Radiology (J.A.K., D.B.M., D.C.M., P.J.H., C.F.D., V.V.H., R.T.H., M.R.A., S.W.H., D.L.C.) and
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Bogdanova-Mihaylova P, Austin N, Alexander MD, Cassidy L, Murphy RP, Walsh RA, Murphy SM. Spastic ataxia associated with colour vision deficiency due to DDHD2 mutations. Eur J Neurol 2019; 27:e9-e10. [PMID: 31532039 DOI: 10.1111/ene.14075] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2019] [Accepted: 08/21/2019] [Indexed: 11/27/2022]
Affiliation(s)
| | - N Austin
- Department of Psychology, Tallaght University Hospital, Dublin, Ireland
| | - M D Alexander
- Department of Neurophysiology, Tallaght University Hospital, Dublin, Ireland.,Academic Unit of Neurology, Trinity College Dublin, Dublin, Ireland
| | - L Cassidy
- Department of Ophthalmology, Tallaght University Hospital, Dublin, Ireland
| | - R P Murphy
- Department of Neurology, Tallaght University Hospital, Dublin, Ireland.,Academic Unit of Neurology, Trinity College Dublin, Dublin, Ireland
| | - R A Walsh
- Department of Neurology, Tallaght University Hospital, Dublin, Ireland.,Academic Unit of Neurology, Trinity College Dublin, Dublin, Ireland
| | - S M Murphy
- Department of Neurology, Tallaght University Hospital, Dublin, Ireland.,Academic Unit of Neurology, Trinity College Dublin, Dublin, Ireland
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de Havenon A, Muhina HJ, Parker DL, McNally JS, Alexander MD. Effect of Time Elapsed since Gadolinium Administration on Atherosclerotic Plaque Enhancement in Clinical Vessel Wall MR Imaging Studies. AJNR Am J Neuroradiol 2019; 40:1709-1711. [PMID: 31515211 DOI: 10.3174/ajnr.a6191] [Citation(s) in RCA: 4] [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] [Subscribe] [Scholar Register] [Received: 05/20/2019] [Accepted: 07/17/2019] [Indexed: 11/07/2022]
Abstract
Vessel wall MR imaging is a useful tool for the evaluation of intracranial atherosclerotic disease. Enhancement can be particularly instructive. This study investigated the impact of the duration between contrast administration and image acquisition. The cohort with the longest duration had the greatest increase in signal intensity change. When using vessel wall MR imaging to assess intracranial atherosclerotic disease, protocols should be designed to maximize the duration between contrast administration and image acquisition to best demonstrate enhancement.
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Affiliation(s)
| | - H J Muhina
- the School of Medicine(H.J.M.), University of Utah, Salt Lake City, Utah
| | - D L Parker
- From the Departments of Radiology and Imaging Sciences (M.D.A., D.L.P., J.S.M.)
| | - J S McNally
- From the Departments of Radiology and Imaging Sciences (M.D.A., D.L.P., J.S.M.)
| | - M D Alexander
- From the Departments of Radiology and Imaging Sciences (M.D.A., D.L.P., J.S.M.) .,Neurosurgery (M.D.A.)
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Alexander MD, Hughes N, Cooke DL, Hess CP, Frieden IJ, Phelps AS, Dowd CF. Revisiting classic MRI findings of venous malformations: Changes in protocols may lead to potential misdiagnosis. Neuroradiol J 2018; 31:509-512. [PMID: 30089411 DOI: 10.1177/1971400918791787] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
Abstract
Introduction Magnetic resonance imaging (MRI) is most sensitive and specific for characterizing venous malformations (VMs). VMs typically demonstrate central enhancement on delayed-contrast imaging. Fluid-fluid levels (FFLs) are uncommon in VMs and common in lymphatic malformations (LMs). Technology has advanced since the initial description of these findings. Rates of detection of these MRI findings in VMs may have changed as MRI technology and techniques have evolved. Methods and methods A prospectively maintained database from a multidisciplinary vascular anomalies clinic was reviewed to identify patients with final diagnosis of VM or LM. Patients with reviewable contrast-enhanced MRIs were selected, reviewing the oldest MRI studies in the database against the newest MRI studies to identify equal numbers of patients from the temporal extremes. Imaging was reviewed to assess for presence of FFLs. Enhancement was quantified by measuring signal in the same location of the lesion both on pre- and postcontrast sequences Results Forty patients were identified for analysis. Twenty studies with sufficient archived imaging for review were performed between 1995 and 2006; 20 such studies were performed between 2011 and 2012. The new imaging cohort had higher rates of FFL visualization ( p = 0.001). Correlation was found between time to imaging following contrast and degree of enhancement ( p < 0.001). Inverse correlation was found between scan date and time to contrast ( p = 0.001) and scan date and enhancement ( p = 0.021). Conclusion FFLs should no longer be considered exclusionary for the diagnosis of VMs. Timing following contrast administration should be maximized to increase degree of enhancement to confirm the diagnosis of VMs.
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Affiliation(s)
- M D Alexander
- 1 Department of Radiology and Imaging Sciences, University of Utah, USA
| | - N Hughes
- 2 Department of Radiology, Memorial University of Newfoundland, Canada
| | - D L Cooke
- 3 Department of Radiology and Biomedical Imaging, University of California San Francisco, USA
| | - C P Hess
- 3 Department of Radiology and Biomedical Imaging, University of California San Francisco, USA
| | - I J Frieden
- 4 Department of Dermatology, University of California San Francisco, USA
| | - A S Phelps
- 3 Department of Radiology and Biomedical Imaging, University of California San Francisco, USA
| | - C F Dowd
- 3 Department of Radiology and Biomedical Imaging, University of California San Francisco, USA
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Bogdanova‐Mihaylova P, Murphy RPJ, Alexander MD, McHugh JC, Foley AR, Brett F, Murphy SM. Congenital myasthenic syndrome due to
DPAGT
1
mutations mimicking congenital myopathy in an Irish family. Eur J Neurol 2018; 25:e22-e23. [DOI: 10.1111/ene.13532] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/10/2017] [Accepted: 11/20/2017] [Indexed: 11/30/2022]
Affiliation(s)
- P. Bogdanova‐Mihaylova
- Department of Neurology Adelaide and Meath Hospitals incorporating the National Children's Hospital Dublin
| | - R. P. J. Murphy
- Department of Neurology Adelaide and Meath Hospitals incorporating the National Children's Hospital Dublin
| | - M. D. Alexander
- Department of Clinical Neurophysiology Adelaide and Meath Hospitals incorporating the National Children's Hospital Dublin
- Academic Unit of Neurology Trinity College Dublin Dublin Ireland
| | - J. C. McHugh
- Department of Clinical Neurophysiology Adelaide and Meath Hospitals incorporating the National Children's Hospital Dublin
- Academic Unit of Neurology Trinity College Dublin Dublin Ireland
| | - A. Reghan Foley
- Neuromuscular and Neurogenetic Disorders of Childhood Section, Neurogenetics Branch, National Institute of Neurological Disorders and Stroke, National Institutes of Health Bethesda MDUSA
| | - F. Brett
- Histopathology Department Beaumont Hospital Dublin Ireland
| | - S. M. Murphy
- Department of Neurology Adelaide and Meath Hospitals incorporating the National Children's Hospital Dublin
- Academic Unit of Neurology Trinity College Dublin Dublin Ireland
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Alexander MD, Nicholson AD, Darflinger RJ, Settecase F, Cooke DL, Dowd CF, Amans MR, Higashida RT, Hetts SW, Halbach VV. Effects on vessel measurement accuracy and subsequent occlusion after calcium channel blocker infusion during treatment of cerebral aneurysms with the Pipeline embolization device. Interv Neuroradiol 2017; 23:47-51. [DOI: 10.1177/1591019916674916] [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: 11/17/2022] Open
Abstract
Introduction/Purpose To achieve aneurysm occlusion, flow diverters (FDs) must be accurately sized to maximize coverage over the neck and induce thrombosis. Catheterization for diagnostic angiography can cause vasospasm that may affect vessel measurements. This study evaluates impacts of intra-arterial infusion of a calcium channel blocker (CCB) on angiographic measurements in patients treated with FDs to determine effects on final diameter of the FD and subsequent occlusion. Materials and methods Pre-treatment measurements were recorded for diameter of the distal and proximal landing zones and maximum and minimum diameters between these segments. Post-treatment measurements of the stent following deployment were recorded at these locations. When CCB was infused, post-infusion pre-treatment measurements were recorded. Rates of occlusion were noted for all patients. T-tests were performed to assess for differences in pre- and post-treatment measurements and rates of occlusion between groups with and without CCB infusion. Results Twenty-eight FDs were deployed to treat 25 aneurysms in 24 patients. CCB infusion was performed prior to deployment of 12 (42.9%) devices. No significant difference was noted between groups for pre- and post-treatment measurement changes. Confirmed aneurysm occlusion was more likely to occur in the CCB infusion group (88.9% vs. 36.4%, p = 0.009). Conclusion Optimization of device sizing is important to increase FD density over the aneurysm neck and promote thrombosis. To improve measurement accuracy, CCB infusion can reduce effects of mild vasospasm. Subsequent aneurysm occlusion was more likely to occur following FD treatment when device size selection was based on measurements performed following CCB infusion.
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Affiliation(s)
- MD Alexander
- University of California San Francisco, Department of Radiology and Biomedical Imaging, USA
| | - AD Nicholson
- University of California San Francisco, Department of Radiology and Biomedical Imaging, USA
| | - RJ Darflinger
- University of California San Francisco, Department of Radiology and Biomedical Imaging, USA
| | - F Settecase
- University of California San Francisco, Department of Radiology and Biomedical Imaging, USA
| | - DL Cooke
- University of California San Francisco, Department of Radiology and Biomedical Imaging, USA
| | - CF Dowd
- University of California San Francisco, Department of Radiology and Biomedical Imaging, USA
| | - MR Amans
- University of California San Francisco, Department of Radiology and Biomedical Imaging, USA
| | - RT Higashida
- University of California San Francisco, Department of Radiology and Biomedical Imaging, USA
| | - SW Hetts
- University of California San Francisco, Department of Radiology and Biomedical Imaging, USA
| | - VV Halbach
- University of California San Francisco, Department of Radiology and Biomedical Imaging, USA
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Alexander MD, Cooke DL, Nelson J, Guo DE, Dowd CF, Higashida RT, Halbach VV, Lawton MT, Kim H, Hetts SW. Association between Venous Angioarchitectural Features of Sporadic Brain Arteriovenous Malformations and Intracranial Hemorrhage. AJNR Am J Neuroradiol 2015; 36:949-52. [PMID: 25634722 DOI: 10.3174/ajnr.a4224] [Citation(s) in RCA: 40] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2014] [Accepted: 10/21/2014] [Indexed: 11/07/2022]
Abstract
BACKGROUND AND PURPOSE Intracranial hemorrhage is the most serious outcome for brain arteriovenous malformations. This study examines associations between venous characteristics of these lesions and intracranial hemorrhage. MATERIALS AND METHODS Statistical analysis was performed on a prospectively maintained data base of brain AVMs evaluated at an academic medical center. DSA, CT, and MR imaging studies were evaluated to classify lesion side, drainage pattern, venous stenosis, number of draining veins, venous ectasia, and venous reflux. Logistic regression analyses were performed to identify the association of these angiographic features with intracranial hemorrhage of any age at initial presentation. RESULTS Exclusively deep drainage (OR, 3.42; 95% CI, 1.87-6.26; P < .001) and a single draining vein (OR, 1.98; 95% CI, 1.26-3.08; P = .002) were associated with hemorrhage, whereas venous ectasia (OR, 0.52; 95% CI, 0.34-0.78; P = .002) was inversely associated with hemorrhage. CONCLUSIONS Analysis of venous characteristics of brain AVMs may help determine their prognosis and thereby identify lesions most appropriate for treatment.
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Affiliation(s)
- M D Alexander
- From the Department of Radiology (M.D.A.), University of Washington, Seattle, Washington
| | - D L Cooke
- Department of Radiology and Biomedical Imaging (D.L.C., C.F.D., R.T.H., V.V.H., S.W.H.)
| | - J Nelson
- Center for Cerebrovascular Research, Department of Anesthesia and Perioperative Care (J.N., D.E.G., H.K.)
| | - D E Guo
- Center for Cerebrovascular Research, Department of Anesthesia and Perioperative Care (J.N., D.E.G., H.K.)
| | - C F Dowd
- Department of Radiology and Biomedical Imaging (D.L.C., C.F.D., R.T.H., V.V.H., S.W.H.)
| | - R T Higashida
- Department of Radiology and Biomedical Imaging (D.L.C., C.F.D., R.T.H., V.V.H., S.W.H.)
| | - V V Halbach
- Department of Radiology and Biomedical Imaging (D.L.C., C.F.D., R.T.H., V.V.H., S.W.H.)
| | - M T Lawton
- Department of Neurological Surgery (M.T.L.), University of California, San Francisco, San Francisco, California
| | - H Kim
- Center for Cerebrovascular Research, Department of Anesthesia and Perioperative Care (J.N., D.E.G., H.K.)
| | - S W Hetts
- Department of Radiology and Biomedical Imaging (D.L.C., C.F.D., R.T.H., V.V.H., S.W.H.)
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Alexander MD, Cooke DL, Meyers PM, Amans MR, Dowd CF, Halbach VV, Higashida RT, Hetts SW. Lesion stability characteristics outperform degree of stenosis in predicting outcomes following stenting for symptomatic intracranial atherosclerosis. J Neurointerv Surg 2014; 8:19-23. [PMID: 25416828 DOI: 10.1136/neurintsurg-2014-011482] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [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: 09/21/2014] [Accepted: 11/01/2014] [Indexed: 11/04/2022]
Abstract
BACKGROUND Intracranial atherosclerotic disease (ICAD) causes substantial morbidity and mortality. Treatment decisions have most commonly been driven by the degree of luminal stenosis. This study compares ICAD lesion stability features with percentage stenosis for associations with adverse outcomes following treatment with stents. MATERIALS AND METHODS Retrospective analysis was performed of prospectively maintained procedure logs. Lesions were classified by symptom type as hypoperfusion, non-hypoperfusion, or indeterminate, and pretreatment asymptomatic intervals were noted. Hypoperfusion lesions and indeterminate or non-hypoperfusion lesions with ≥14 days of asymptomatic interval were classified as stable. Percentage stenosis was calculated and compared against these other symptom features for value in predicting technical complication, ischemic stroke, disability, or death at 90 days and 2 years using univariate and multivariate analysis. RESULTS 130 lesions were treated in 124 patients. The only statistically significant percent stenosis finding was lesions with 60-99% stenosis were less likely to have technical complications. In univariate analysis, stroke at 2 years was less common with hypoperfusion and stable lesions. In multivariate analysis, only hypoperfusion status was associated with lower stroke rates at 2 years. CONCLUSIONS Lesion stability features, particularly non-hypoperfusion symptomatology, outperform percentage stenosis in predicting outcomes following treatment of ICAD with stents. Further examination is needed to better classify the natural history of ICAD and more precisely classify lesion stability.
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Affiliation(s)
- M D Alexander
- Department of Radiology, University of Washington, Seattle, Washington, USA
| | - D L Cooke
- Department of Radiology and Biomedical Imaging, University of California San Francisco, San Francisco, California, USA
| | - P M Meyers
- Departments of Radiology and Neurological Surgery, Columbia University, New York, New York, USA
| | - M R Amans
- Department of Radiology and Biomedical Imaging, University of California San Francisco, San Francisco, California, USA
| | - C F Dowd
- Department of Radiology and Biomedical Imaging, University of California San Francisco, San Francisco, California, USA Departments of Neurological Surgery, Neurology, Anesthesia and Perioperative Care, University of California San Francisco, San Francisco, California, USA
| | - V V Halbach
- Department of Radiology and Biomedical Imaging, University of California San Francisco, San Francisco, California, USA Departments of Neurological Surgery, Neurology, Anesthesia and Perioperative Care, University of California San Francisco, San Francisco, California, USA
| | - R T Higashida
- Department of Radiology and Biomedical Imaging, University of California San Francisco, San Francisco, California, USA Departments of Neurological Surgery, Neurology, Anesthesia and Perioperative Care, University of California San Francisco, San Francisco, California, USA
| | - S W Hetts
- Department of Radiology and Biomedical Imaging, University of California San Francisco, San Francisco, California, USA
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13
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Alexander MD, Meyers PM, English JD, Stradford TR, Sung S, Smith WS, Halbach VV, Higashida RT, Dowd CF, Cooke DL, Hetts SW. Symptom differences and pretreatment asymptomatic interval affect outcomes of stenting for intracranial atherosclerotic disease. AJNR Am J Neuroradiol 2014; 35:1157-62. [PMID: 24676000 DOI: 10.3174/ajnr.a3836] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
BACKGROUND AND PURPOSE Different types of symptomatic intracranial stenosis may respond differently to interventional therapy. We investigated symptomatic and pathophysiologic factors that may influence clinical outcomes of patients with intracranial atherosclerotic disease who were treated with stents. MATERIALS AND METHODS A retrospective analysis was performed of patients treated with stents for intracranial atherosclerosis at 4 centers. Patient demographics and comorbidities, lesion features, treatment features, and preprocedural and postprocedural functional status were noted. χ(2) univariate and multivariate logistic regression analysis was performed to assess technical results and clinical outcomes. RESULTS One hundred forty-two lesions in 131 patients were analyzed. Lesions causing hypoperfusion ischemic symptoms were associated with fewer strokes by last contact [χ(2) (1, n = 63) = 5.41, P = .019]. Nonhypoperfusion lesions causing symptoms during the 14 days before treatment had more strokes by last contact [χ(2) (1, n = 136), 4.21, P = .047]. Patients treated with stents designed for intracranial deployment were more likely to have had a stroke by last contact (OR, 4.63; P = .032), and patients treated with percutaneous balloon angioplasty in addition to deployment of a self-expanding stent were less likely to be stroke free at point of last contact (OR, 0.60; P = .034). CONCLUSIONS More favorable outcomes may occur after stent placement for lesions causing hypoperfusion symptoms and when delaying stent placement 7-14 days after most recent symptoms for lesions suspected to cause embolic disease or perforator ischemia. Angioplasty performed in addition to self-expanding stent deployment may lead to worse outcomes, as may use of self-expanding stents rather than balloon-mounted stents.
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Affiliation(s)
- M D Alexander
- From the Department of Radiology, Santa Clara Valley Medical Center, San Jose, California (M.D.A.)
| | - P M Meyers
- Departments of Neurointerventional Surgery (P.M.M.)
| | - J D English
- Department of Neurology, California Pacific Medical Center, San Francisco, California (J.D.E.)
| | - T R Stradford
- Department of Medicine, St Luke's-Roosevelt Hospital, New York, New York (T.R.S.)
| | - S Sung
- Pathology (S.S.), Columbia University, New York, New York
| | | | - V V Halbach
- Radiology and Biomedical Imaging (V.V.H., R.T.H., C.F.D., D.L.C., S.W.H.)Neurological Surgery (V.V.H., R.T.H., C.F.D.), University of California, San Francisco, California
| | - R T Higashida
- Radiology and Biomedical Imaging (V.V.H., R.T.H., C.F.D., D.L.C., S.W.H.)Neurological Surgery (V.V.H., R.T.H., C.F.D.), University of California, San Francisco, California
| | - C F Dowd
- Radiology and Biomedical Imaging (V.V.H., R.T.H., C.F.D., D.L.C., S.W.H.)Neurological Surgery (V.V.H., R.T.H., C.F.D.), University of California, San Francisco, California
| | - D L Cooke
- Radiology and Biomedical Imaging (V.V.H., R.T.H., C.F.D., D.L.C., S.W.H.)
| | - S W Hetts
- Radiology and Biomedical Imaging (V.V.H., R.T.H., C.F.D., D.L.C., S.W.H.)
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Alexander MD, English J, Hetts SW. Occipital artery anastomosis to vertebral artery causing pulsatile tinnitus. Case Reports 2013; 2013:bcr-2012-010632. [DOI: 10.1136/bcr-2012-010632] [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] Open
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15
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Alexander MD, Oliff MC, Olorunsola OG, Brus-Ramer M, Nickoloff EL, Meyers PM. Patient radiation exposure during diagnostic and therapeutic interventional neuroradiology procedures. J Neurointerv Surg 2009; 2:6-10. [PMID: 21990551 DOI: 10.1136/jnis.2009.000802] [Citation(s) in RCA: 51] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
Abstract
PURPOSE Increasing in number and complexity, interventional neuroradiology (INR) procedures are becoming an important source of radiation exposure for patients. In accordance with the ALARA principle, radiation exposure during INR procedures should be curtailed as much as possible while reaching successful treatment outcomes. Moreover, the extent of radiation exposure should be one outcome measure used to assess new technologies and procedural efficacy, and training programs should include techniques for exposure limitation. This study provides a methodology and preliminary data to assess radiation exposure during different INR procedure types. MATERIALS AND METHODS All patients undergoing endovascular procedures in two biplanar dedicated neuroangiography suites at a major academic medical center were monitored according to procedure type, pathological indication, fluoroscopy time and machine-generated patient dose estimates between April 2006 and July 2008. RESULTS 1678 patients underwent cerebral arteriography during the study period. Women (62.1%) accounted for the majority of patients, but men (38.9%) were more likely to undergo an interventional procedure than women (32.8%). Diagnostic studies accounted for 64.9% of procedures. Variable exposures were found between diagnostic and interventional procedures. Exposure differed depending on indications for the procedure and procedure type. CONCLUSION Radiation exposure is an increasingly important consideration in the development of minimally invasive neurological procedures including cerebral angiography and INR. The type of procedure and lesion type allow the practitioner to estimate radiation exposure. Such information informs the clinical decision making process. Normative data should be collected and used for comparison purposes as one measure of technical and procedural success.
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Affiliation(s)
- M D Alexander
- Columbia University, College of Physicians and Surgeons, New York, New York 10032, USA.
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16
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Abstract
Sequence variations with biologic effect in ALS have been identified in the gene for vascular endothelial growth factor (VEGF). The gene for a related protein, angiogenin, lies on chromosome 14q11.2. Analysis of the angiogenin (ANG) gene in the authors' population has demonstrated a significant allelic association with the rs11701 single nucleotide polymorphism (SNP) and identified a novel mutation in two individuals with sporadic ALS that potentially inhibits angiogenin function. These observations propose a candidate region for ALS on chromosome 14q11.2 and suggest that other genes with similar function to VEGF may be important in the pathogenesis of ALS.
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Affiliation(s)
- M J Greenway
- Department of Clinical Neurological Sciences, Royal College of Surgeons in Ireland.
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Heasley VL, Wadley BD, Alexander MD, Anderson JD, Anderson JH, Allen RT, Hernandez ML, Ismail ML, Sigmund GA, Shellhamer DF. A reinvestigation of the synthesis of Hantzsch's acid: comparison of derivatives of Hantzsch's acid with a product from the reaction of 2, 4,6-trichlorophenol and hypochlorite ion in methanol. J Org Chem 2000; 65:8111-3. [PMID: 11073632 DOI: 10.1021/jo0010025] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- V L Heasley
- Department of Chemistry, Point Loma Nazarene University, San Diego, California 92106, USA.
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Dang TD, Mather PT, Alexander MD, Grayson CJ, Houtz MD, Spry RJ, Arnold FE. Synthesis and characterization of fluorinated benzoxazole polymers with highTg and low dielectric constant. ACTA ACUST UNITED AC 2000. [DOI: 10.1002/(sici)1099-0518(20000601)38:11<1991::aid-pola80>3.0.co;2-4] [Citation(s) in RCA: 46] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
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Kumar V, Ackerman JH, Alexander MD, Bell MR, Christiansen RG, Dung JS, Jaeger EP, Herrmann JL, Krolski ME, McKloskey P. Androgen receptor affinity of 5'-acyl furanosteroids. J Med Chem 1994; 37:4227-36. [PMID: 7990121 DOI: 10.1021/jm00050a019] [Citation(s) in RCA: 17] [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: 01/28/2023]
Abstract
Syntheses of 5'-acyl furanosteroids are described from the corresponding unsubstituted [3,2-b]furanosteroids using acid anhydrides and acid chlorides in the presence or absence of Lewis acids. New methods have been developed to prepare 5'-acetyl derivatives: reduction of a 5'-trichloroacetyl intermediate either by sodium formaldehyde sulfoxylate or with 10% Pd/C. Most of these 5'-acyl derivatives bind to the rat ventral prostate androgen receptor. However the antiandrogenic activity was diminished when compared with 4,5'-methylsulfonyl furanosteroid. Biological studies revealed that 5'-acyl furanosteroids were either androgens or modest antiandrogens. The electrostatic potential maps of the substructures of 3, 4, and 5'-acetyl syn- and anti-furanosteroids showed striking differences which may explain, to some extent, the lack of significant antiandrogenic activity of 5'-acyl furanosteroids.
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Affiliation(s)
- V Kumar
- Department of Medicinal Chemistry, Sterling Winthrop Pharmaceutical Research Division, Collegeville, Pennsylvania 19426-0900
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Greene B, Hosea M, McPherson R, Henzl M, Alexander MD, Darnall DW. Interaction of gold(I) and gold(III) complexes with algal biomass. Environ Sci Technol 1986; 20:627-632. [PMID: 19994962 DOI: 10.1021/es00148a014] [Citation(s) in RCA: 88] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/28/2023]
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Darnall DW, Greene B, Henzl MT, Hosea JM, McPherson RA, Sneddon J, Alexander MD. Selective recovery of gold and other metal ions from an algal biomass. Environ Sci Technol 1986; 20:206-8. [PMID: 22288814 DOI: 10.1021/es00144a018] [Citation(s) in RCA: 111] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/04/2023]
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23
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Alexander MD, Carrick BM, Sweetman AJ. Modulation of guinea-pig peritoneal macrophage Fc receptor activity using D-penicillamine. Methods Find Exp Clin Pharmacol 1983; 5:419-24. [PMID: 6668961] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
Abstract
The influence of D-penicillamine and 2,2'-pyridylisatogen tosylate upon guinea-pig peritoneal IgG Fc receptor activity is examined. D-penicillamine pretreatment of guinea-pig peritoneal cells is shown to selectively reduce the specificity of the interaction between 7s-human IgG and the guinea-pig macrophage Fc receptor population. In contrast, the drug did not influence the binding of guinea-pig 7s IgG2 nor the uptake of aggregated heterologous or homologous Immunoglobulin. Both D-penicillamine and 2,2'-pyridylisatogen tosylate are shown to influence particulate immune complex binding to pretreatment peritoneal cells.
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Alexander MD, Carrick BM. Selective action of D-penicillamine on guinea pig peritoneal macrophage Fc gamma receptors for homologous, monomeric IgG1. Immunol Lett 1983; 6:219-22. [PMID: 6224742 DOI: 10.1016/0165-2478(83)90007-x] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
Abstract
Guinea pig oil-induced peritoneal exudates were pretreated with D-penicillamine. The binding of homologous, monomeric IgG2 and IgG1 to normal and pretreated exudates was examined. Whereas the 7S IgG2-IgG2 Fc gamma receptor interaction remains unaffected by the pretreatment, the binding of IgG1 to the IgG Fc gamma receptor population was affected. The significance of the selective effect of D-penicillamine is discussed.
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Alexander MD, Bloom KR, Hart P, D'Silva F, Murgo JP. Atrial septal aneurysm: a cause for midsystolic click. Report of a case and review of the literature. Circulation 1981; 63:1186-8. [PMID: 7008966 DOI: 10.1161/01.cir.63.5.1186] [Citation(s) in RCA: 42] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
Abstract
A patient who was evaluated for a midsystolic click was found to have an aneurysm of the atrial septum as an isolated anomaly. Bulging of this aneurysm into the right atrium was associated with the production of the click. Echo-, phono-, and angiocardiographic features are presented, with a review of the literature on atrial septal aneurysms. These aneurysms, although rare, should be considered in the differential diagnosis of patients with midsystolic click.
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Abstract
Human myeloma proteins IgG1 and IgG3 have been compared for their ability to inhibit the binding of native particular immune complexes, containing either subclass, to peripheral blood monocytes. In contrast to some earlier findings, 7s IgG3 has been shown to be more effective than 7s IgG1.
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Alexander MD, Andrews JA, Leslie RG, Wood NJ. The binding of human and guinea-pig IgG subclasses to homologous macrophage and monocyte Fc receptors. Immunology 1978; 35:115-23. [PMID: 680795 PMCID: PMC1457241] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022] Open
Abstract
Guinea-pig IgG2 and IgT1 bind to contiguous Fc receptors on homologous peritoneal macrophages. Equilibrium association constants determined for the binding of human IgG subclasses to homologous peripheral blood monocytes show that the order of binding is IgG1 greater than IgG3 greater than IgG4 greater than IgG2. Direct binding and rosette assay techniques independently established that both guinea-pig IgG2 and human IgG bind to homologous macrophage-monocyte Fc receptors through a site present in whole Fc (CH2. CH3)2, but absent in pFc' subfragments (CH3)2.
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Abstract
The hydrolysis products from short term exposure of guinea pig IgG2 to papain and pepsin have been characterized. Papain hydrolysis liberates 4 types of Fc fragment, only one of which retains both an interchain disulfide bond and an intact CH2 domain, cFc, mol.wt. 56 000. The other three fragments noncovalently linked Fc (nFc) (mol.wt. 56 000), incomplete Fc (iFc) (mol.wt. 39 000) and Fc' (23 000) represent further degradation products of covalently linked complete Fc (cFc). The cytophilic activities of these fragments as well as F(ab')2 and pFc' from pepsin hydrolysis, were studied to determine the domain(s) responsible for binding to homologous peritoneal macrophages. Only the native immunoglobulin and the intact cFc manifested cytophilic activity; in particular pepsin-derived pFc' and Fc' were inactive. Following mild reduction and alkylation, performed to affect only the interchain disulfide bonds, the cytophilic activity of cFc was markedly reduced. The low cytophilic activity in the pFc' fragment suggests that the CH2 domains play a major part in binding to the macrophage Fc receptor through a site(s) stabilized by the interchain disulfide bonds.
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Watts DC, Baldwin E, Alexander MD. Activity and stability of carbamoyl phosphate synthase from rat liver. Comp Biochem Physiol 1969; 29:319-324. [PMID: 5795822 DOI: 10.1016/0010-406x(69)91752-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/21/2023]
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Alexander MD, Haslewood ES, Haslewood GA, Watts DC, Watts RL. Osmotic control and urea biosynthesis in selachians. Comp Biochem Physiol 1968; 26:971-8. [PMID: 5758317 DOI: 10.1016/0010-406x(68)90017-0] [Citation(s) in RCA: 20] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/16/2023]
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