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Huck DM, Weber B, Schreiber B, Pandav J, Parks S, Hainer J, Brown JM, Divakaran S, Blankstein R, Dorbala S, Trinquart L, Chandraker A, Di Carli MF. Comparative Effectiveness of PET and SPECT MPI for Predicting Cardiovascular Events After Kidney Transplant. Circ Cardiovasc Imaging 2024; 17:e015858. [PMID: 38227694 PMCID: PMC10794031 DOI: 10.1161/circimaging.123.015858] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/07/2023] [Accepted: 12/08/2023] [Indexed: 01/18/2024]
Abstract
BACKGROUND Advanced chronic kidney disease is associated with high cardiovascular risk, even after kidney transplant. Pretransplant cardiac testing may identify patients who require additional assessment before transplant or would benefit from risk optimization. The objective of the current study was to determine the relative prognostic utility of pretransplant positron emission tomography (PET) and single-photon emission computed tomography (SPECT) myocardial perfusion imaging (MPI) for posttransplant major adverse cardiovascular events (MACEs). METHODS We retrospectively followed patients who underwent MPI before kidney transplant for the occurrence of MACE after transplant including myocardial infarction, stroke, heart failure, and cardiac death. An abnormal MPI result was defined as a total perfusion deficit >5% of the myocardium. To determine associations of MPI results with MACE, we utilized Cox hazard regression with propensity weighting for PET versus SPECT with model factors, including demographics and cardiovascular risk factors. RESULTS A total of 393 patients underwent MPI (208 PET and 185 SPECT) and were followed for a median of 5.9 years post-transplant. Most were male (58%), median age was 58 years, and there was a high burden of hypertension (88%) and diabetes (33%). A minority had abnormal MPI (n=58, 15%). In propensity-weighted hazard regression, abnormal PET result was associated with posttransplant MACE (hazard ratio, 3.02 [95% CI, 1.78-5.11]; P<0.001), while there was insufficient evidence of an association of abnormal SPECT result with MACE (1.39 [95% CI, 0.72-2.66]; P=0.33). The explained relative risk of the PET result was higher than the SPECT result (R2 0.086 versus 0.007). Normal PET was associated with the lowest risk of MACE (2.2%/year versus 3.6%/year for normal SPECT; P<0.001). CONCLUSIONS Kidney transplant recipients are at high cardiovascular risk, despite a minority having obstructive coronary artery disease on MPI. PET MPI findings predict posttransplant MACE. Normal PET may better discriminate lower risk patients compared with normal SPECT, which should be confirmed in a larger prospective study.
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Affiliation(s)
- Daniel M Huck
- CV Imaging Program (D.M.H., B.W., S.P., J.H., J.M.B., S. Divakaran, R.B., S. Dorbala, M.F.D.C.), Department of Medicine, Brigham and Women's Hospital, Harvard Medical School, Boston, MA
- CV Division (D.M.H., B.W., J.M.B., S. Divakaran, R.B., S. Dorbala, M.F.D.C.), Department of Medicine, Brigham and Women's Hospital, Harvard Medical School, Boston, MA
- CV Imaging Program (D.M.H., B.W., S.P., J.H., J.M.B., S. Divakaran, R.B., S. Dorbalat, M.F.D.C.), Department of Radiology, Brigham and Women's Hospital, Harvard Medical School, Boston, MA
| | - Brittany Weber
- CV Imaging Program (D.M.H., B.W., S.P., J.H., J.M.B., S. Divakaran, R.B., S. Dorbala, M.F.D.C.), Department of Medicine, Brigham and Women's Hospital, Harvard Medical School, Boston, MA
- CV Division (D.M.H., B.W., J.M.B., S. Divakaran, R.B., S. Dorbala, M.F.D.C.), Department of Medicine, Brigham and Women's Hospital, Harvard Medical School, Boston, MA
- CV Imaging Program (D.M.H., B.W., S.P., J.H., J.M.B., S. Divakaran, R.B., S. Dorbalat, M.F.D.C.), Department of Radiology, Brigham and Women's Hospital, Harvard Medical School, Boston, MA
| | - Brittany Schreiber
- Division of Nephrology (B.S., J.P., A.C.), Department of Medicine, Brigham and Women's Hospital, Harvard Medical School, Boston, MA
| | - Jay Pandav
- Division of Nephrology (B.S., J.P., A.C.), Department of Medicine, Brigham and Women's Hospital, Harvard Medical School, Boston, MA
| | - Sean Parks
- CV Imaging Program (D.M.H., B.W., S.P., J.H., J.M.B., S. Divakaran, R.B., S. Dorbala, M.F.D.C.), Department of Medicine, Brigham and Women's Hospital, Harvard Medical School, Boston, MA
- CV Imaging Program (D.M.H., B.W., S.P., J.H., J.M.B., S. Divakaran, R.B., S. Dorbalat, M.F.D.C.), Department of Radiology, Brigham and Women's Hospital, Harvard Medical School, Boston, MA
- Division of Nuclear Medicine and Molecular Imaging (S.P., J.H., S. Divakaran, S. Dorbala, M.F.D.C.), Department of Radiology, Brigham and Women's Hospital, Harvard Medical School, Boston, MA
| | - Jon Hainer
- CV Imaging Program (D.M.H., B.W., S.P., J.H., J.M.B., S. Divakaran, R.B., S. Dorbala, M.F.D.C.), Department of Medicine, Brigham and Women's Hospital, Harvard Medical School, Boston, MA
- CV Imaging Program (D.M.H., B.W., S.P., J.H., J.M.B., S. Divakaran, R.B., S. Dorbalat, M.F.D.C.), Department of Radiology, Brigham and Women's Hospital, Harvard Medical School, Boston, MA
- Division of Nuclear Medicine and Molecular Imaging (S.P., J.H., S. Divakaran, S. Dorbala, M.F.D.C.), Department of Radiology, Brigham and Women's Hospital, Harvard Medical School, Boston, MA
| | - Jenifer M Brown
- CV Imaging Program (D.M.H., B.W., S.P., J.H., J.M.B., S. Divakaran, R.B., S. Dorbala, M.F.D.C.), Department of Medicine, Brigham and Women's Hospital, Harvard Medical School, Boston, MA
- CV Division (D.M.H., B.W., J.M.B., S. Divakaran, R.B., S. Dorbala, M.F.D.C.), Department of Medicine, Brigham and Women's Hospital, Harvard Medical School, Boston, MA
- CV Imaging Program (D.M.H., B.W., S.P., J.H., J.M.B., S. Divakaran, R.B., S. Dorbalat, M.F.D.C.), Department of Radiology, Brigham and Women's Hospital, Harvard Medical School, Boston, MA
| | - Sanjay Divakaran
- CV Imaging Program (D.M.H., B.W., S.P., J.H., J.M.B., S. Divakaran, R.B., S. Dorbala, M.F.D.C.), Department of Medicine, Brigham and Women's Hospital, Harvard Medical School, Boston, MA
- CV Division (D.M.H., B.W., J.M.B., S. Divakaran, R.B., S. Dorbala, M.F.D.C.), Department of Medicine, Brigham and Women's Hospital, Harvard Medical School, Boston, MA
- CV Imaging Program (D.M.H., B.W., S.P., J.H., J.M.B., S. Divakaran, R.B., S. Dorbalat, M.F.D.C.), Department of Radiology, Brigham and Women's Hospital, Harvard Medical School, Boston, MA
- Division of Nuclear Medicine and Molecular Imaging (S.P., J.H., S. Divakaran, S. Dorbala, M.F.D.C.), Department of Radiology, Brigham and Women's Hospital, Harvard Medical School, Boston, MA
| | - Ron Blankstein
- CV Imaging Program (D.M.H., B.W., S.P., J.H., J.M.B., S. Divakaran, R.B., S. Dorbala, M.F.D.C.), Department of Medicine, Brigham and Women's Hospital, Harvard Medical School, Boston, MA
- CV Division (D.M.H., B.W., J.M.B., S. Divakaran, R.B., S. Dorbala, M.F.D.C.), Department of Medicine, Brigham and Women's Hospital, Harvard Medical School, Boston, MA
- CV Imaging Program (D.M.H., B.W., S.P., J.H., J.M.B., S. Divakaran, R.B., S. Dorbalat, M.F.D.C.), Department of Radiology, Brigham and Women's Hospital, Harvard Medical School, Boston, MA
| | - Sharmila Dorbala
- CV Imaging Program (D.M.H., B.W., S.P., J.H., J.M.B., S. Divakaran, R.B., S. Dorbala, M.F.D.C.), Department of Medicine, Brigham and Women's Hospital, Harvard Medical School, Boston, MA
- CV Division (D.M.H., B.W., J.M.B., S. Divakaran, R.B., S. Dorbala, M.F.D.C.), Department of Medicine, Brigham and Women's Hospital, Harvard Medical School, Boston, MA
- Division of Nuclear Medicine and Molecular Imaging (S.P., J.H., S. Divakaran, S. Dorbala, M.F.D.C.), Department of Radiology, Brigham and Women's Hospital, Harvard Medical School, Boston, MA
| | - Ludovic Trinquart
- Institute for Clinical Research and Health Policy Studies, Tufts Medical Center, Boston, MA (L.T.)
- Tufts Clinical and Translational Science Institute, Tufts University, Boston, MA (L.T.)
| | - Anil Chandraker
- Division of Nephrology (B.S., J.P., A.C.), Department of Medicine, Brigham and Women's Hospital, Harvard Medical School, Boston, MA
| | - Marcelo F Di Carli
- CV Imaging Program (D.M.H., B.W., S.P., J.H., J.M.B., S. Divakaran, R.B., S. Dorbala, M.F.D.C.), Department of Medicine, Brigham and Women's Hospital, Harvard Medical School, Boston, MA
- CV Division (D.M.H., B.W., J.M.B., S. Divakaran, R.B., S. Dorbala, M.F.D.C.), Department of Medicine, Brigham and Women's Hospital, Harvard Medical School, Boston, MA
- CV Imaging Program (D.M.H., B.W., S.P., J.H., J.M.B., S. Divakaran, R.B., S. Dorbalat, M.F.D.C.), Department of Radiology, Brigham and Women's Hospital, Harvard Medical School, Boston, MA
- Division of Nuclear Medicine and Molecular Imaging (S.P., J.H., S. Divakaran, S. Dorbala, M.F.D.C.), Department of Radiology, Brigham and Women's Hospital, Harvard Medical School, Boston, MA
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McCue C, Atari A, Parks S, Tseng YY, Varanasi KK. Reducing Cancer Cell Adhesion using Microtextured Surfaces. Small 2023; 19:e2302401. [PMID: 37559167 DOI: 10.1002/smll.202302401] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/21/2023] [Revised: 06/30/2023] [Indexed: 08/11/2023]
Abstract
For the past century, trypsin has been the primary method of cell dissociation, largely without any major changes to the process. Enzymatic cell detachment strategies for large-scale cell culturing processes are popular but can be labor-intensive, potentially lead to the accumulation of genetic mutations, and produce large quantities of liquid waste. Therefore, engineering surfaces to lower cell adhesion strength could enable the next generation of cell culture surfaces for delicate primary cells and automated, high-throughput workflows. In this study, a process for creating microtextured polystyrene (PS) surfaces to measure the impact of microposts on the adhesion strength of cells is developed. Cell viability and proliferation assays show comparable results in two cancer cell lines between micropost surfaces and standard cell culture vessels. However, cell image analysis on microposts reveals that cell area decreases by half, and leads to an average twofold increase in cell length per area. Using a microfluidic-based method up to a seven times greater percentage of cells are removed from micropost surfaces than the flat control surfaces. These results show that micropost surfaces enable decreased cell adhesion strength while maintaining similar cell viabilities and proliferation as compared to flat PS surfaces.
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Affiliation(s)
- Caroline McCue
- Department of Mechanical Engineering, Massachusetts Institute of Technology, 77 Massachusetts Ave, Cambridge, MA, 02139, USA
| | - Adel Atari
- Cancer Program, Broad Institute of Harvard and MIT, 415 Main St, Cambridge, MA, 02142, USA
| | - Sean Parks
- Department of Mechanical Engineering, Massachusetts Institute of Technology, 77 Massachusetts Ave, Cambridge, MA, 02139, USA
| | - Yuen-Yi Tseng
- Cancer Program, Broad Institute of Harvard and MIT, 415 Main St, Cambridge, MA, 02142, USA
| | - Kripa K Varanasi
- Department of Mechanical Engineering, Massachusetts Institute of Technology, 77 Massachusetts Ave, Cambridge, MA, 02139, USA
- Cancer Program, Broad Institute of Harvard and MIT, 415 Main St, Cambridge, MA, 02142, USA
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Huck DM, Weber B, Parks S, Divakaran S, Brown JM, Bibbo CF, Barrett L, Hainer J, Bay C, Martell L, Kogelman L, Triant VA, Chu J, Lin NH, Melbourne K, Sax PE, Di Carli MF. Coronary Microcirculatory Dysfunction in People With HIV and Its Association With Antiretroviral Therapy. J Am Heart Assoc 2023; 12:e029541. [PMID: 37947105 PMCID: PMC10727301 DOI: 10.1161/jaha.123.029541] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/19/2023] [Accepted: 07/18/2023] [Indexed: 11/12/2023]
Abstract
BACKGROUND HIV infection and abacavir-containing antiretroviral regimens are associated with vascular endothelial dysfunction and increased cardiovascular risk. Positron emission tomography (PET)-derived myocardial blood flow reserve (MBFR), the ratio of vasodilator stress to rest myocardial blood flow, is a well-validated measure of coronary microvascular health and marker of cardiovascular risk. Our objective was to compare MBFR among people with HIV (PWH) with matched non-HIV controls and to assess whether switching from dolutegravir/lamivudine/abacavir to the non-abacavir regimen bictegravir/emtricitabine/tenofovir alafenamide (TAF) would improve MBFR. METHODS AND RESULTS Thirty-seven PWH were 1:2 matched on cardiovascular risk factors to 75 people without HIV, and MBFR corrected for differences in resting hemodynamics was compared in a cross-sectional design. PWH were majority men (68%) with a mean age of 56 years. Mean stress myocardial blood flow (1.83 mL/min per g [95% CI, 1.68-1.98] versus 2.40 mL/min per g [95% CI, 2.25-2.54]; P<0.001) and MBFR (2.18 [95% CI, 1.96-2.40] versus 2.68 [95% CI, 2.47-2.89]; P=0.002) was significantly lower in PWH than in people without HIV. In a single-arm, multicenter trial, a subset of 25 PWH who were virologically suppressed on dolutegravir/lamivudine/abacavir underwent positron emission tomography myocardial perfusion imaging at baseline and after switching to bictegravir/emtricitabine/TAF. MBFR was unchanged after switching to bictegravir/emtricitabine/TAF for a mean of 27 weeks (MBFR, 2.34 to 2.29; P=0.61), except in PWH with impaired MBFR at baseline (<2.00; N=6) in whom MBFR increased from 1.58 to 2.02 (P=0.02). CONCLUSIONS PWH had reduced coronary microvascular function compared with controls without HIV. Coronary microvascular function did not improve after switching from dolutegravir/lamivudine/abacavir to bictegravir/emtricitabine/TAF. REGISTRATION URL: https://www.clinicaltrials.gov; unique identifier: NCT03656783.
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Affiliation(s)
- Daniel M. Huck
- Cardiovascular Imaging Program, Departments of Medicine and RadiologyBrigham and Women’s Hospital, Harvard Medical SchoolBostonMAUSA
| | - Brittany Weber
- Cardiovascular Imaging Program, Departments of Medicine and RadiologyBrigham and Women’s Hospital, Harvard Medical SchoolBostonMAUSA
| | - Sean Parks
- Cardiovascular Imaging Program, Departments of Medicine and RadiologyBrigham and Women’s Hospital, Harvard Medical SchoolBostonMAUSA
| | - Sanjay Divakaran
- Cardiovascular Imaging Program, Departments of Medicine and RadiologyBrigham and Women’s Hospital, Harvard Medical SchoolBostonMAUSA
| | - Jenifer M. Brown
- Cardiovascular Imaging Program, Departments of Medicine and RadiologyBrigham and Women’s Hospital, Harvard Medical SchoolBostonMAUSA
| | - Courtney F. Bibbo
- Cardiovascular Imaging Program, Departments of Medicine and RadiologyBrigham and Women’s Hospital, Harvard Medical SchoolBostonMAUSA
| | - Leanne Barrett
- Cardiovascular Imaging Program, Departments of Medicine and RadiologyBrigham and Women’s Hospital, Harvard Medical SchoolBostonMAUSA
| | - Jon Hainer
- Cardiovascular Imaging Program, Departments of Medicine and RadiologyBrigham and Women’s Hospital, Harvard Medical SchoolBostonMAUSA
| | - Camden Bay
- Department of RadiologyBrigham and Women’s HospitalBostonMAUSA
| | - Laurel Martell
- Cardiovascular Imaging Program, Departments of Medicine and RadiologyBrigham and Women’s Hospital, Harvard Medical SchoolBostonMAUSA
| | - Laura Kogelman
- Division of Geographic Medicine and Infectious DiseasesTufts Medical CenterBostonMAUSA
| | - Virginia A. Triant
- Division of Infectious Diseases, Massachusetts General HospitalHarvard Medical SchoolBostonMAUSA
- Division of General Internal MedicineMassachusetts General Hospital, Harvard Medical SchoolBostonMAUSA
| | - Jacqueline Chu
- Division of Infectious Diseases, Massachusetts General HospitalHarvard Medical SchoolBostonMAUSA
| | - Nina H. Lin
- Division of Infectious DiseasesBoston Medical CenterBostonMAUSA
| | | | - Paul E. Sax
- Division of Infectious Diseases, Department of MedicineBrigham and Women’s Hospital, Harvard Medical SchoolBostonMAUSA
| | - Marcelo F. Di Carli
- Cardiovascular Imaging Program, Departments of Medicine and RadiologyBrigham and Women’s Hospital, Harvard Medical SchoolBostonMAUSA
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Brown JM, Park MA, Kijewski MF, Weber BN, Yang Y, Martell L, Perillo A, Barrett L, Parks S, Hainer J, Dorbala S, Blankstein R, Di Carli MF. Feasibility of Simultaneous Quantification of Myocardial and Renal Perfusion With Cardiac Positron Emission Tomography. Circ Cardiovasc Imaging 2023; 16:e015324. [PMID: 37655498 PMCID: PMC10529360 DOI: 10.1161/circimaging.123.015324] [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] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/03/2023] [Accepted: 08/11/2023] [Indexed: 09/02/2023]
Abstract
BACKGROUND Given the central importance of cardiorenal interactions, mechanistic tools for evaluating cardiorenal physiology are needed. In the heart and kidneys, shared pathways of neurohormonal activation, hypertension, and vascular and interstitial fibrosis implicate the relevance of systemic vascular health. The availability of a long axial field of view positron emission tomography (PET)/computed tomography (CT) system enables simultaneous evaluation of cardiac and renal blood flow. METHODS This study evaluated the feasibility of quantification of renal blood flow using data acquired during routine, clinically indicated 13N-ammonia myocardial perfusion PET/CT. Dynamic PET image data were used to calculate renal blood flow. Reproducibility was assessed by the intraclass correlation coefficient among 3 independent readers. PET-derived renal blood flow was correlated with imaging and clinical parameters in the overall cohort and with histopathology in a small companion study of patients with a native kidney biopsy. RESULTS Among 386 consecutive patients with myocardial perfusion PET/CT, 296 (76.7%) had evaluable images to quantify renal perfusion. PET quantification of renal blood flow was highly reproducible (intraclass correlation coefficient 0.98 [95% CI, 0.93-0.99]) and was correlated with the estimated glomerular filtration rate (r=0.64; P<0.001). Compared across vascular beds, resting renal blood flow was correlated with maximal stress myocardial blood flow and myocardial flow reserve (stress/rest myocardial blood flow), an integrated marker of endothelial health. In patients with kidney biopsy (n=12), resting PET renal blood flow was strongly negatively correlated with histological interstitial fibrosis (r=-0.85; P<0.001). CONCLUSIONS Renal blood flow can be reliably measured from cardiac 13N-ammonia PET/CT and allows for simultaneous assessment of myocardial and renal perfusion, opening a potential novel avenue to interrogate the mechanisms of emerging therapies with overlapping cardiac and renal benefits.
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Affiliation(s)
- Jenifer M. Brown
- Heart and Vascular Center, Division of Cardiovascular Medicine, Department of Medicine, Brigham and Women’s Hospital, Harvard Medical School, Boston, MA, USA
- Cardiovascular Imaging Program, Departments of Medicine and Radiology, Brigham and Women’s Hospital, Harvard Medical School, Boston, MA, USA
| | - Mi-Ae Park
- Department of Radiology, UT Southwestern Medical Center, Dallas, TX, USA
| | - Marie Foley Kijewski
- Cardiovascular Imaging Program, Departments of Medicine and Radiology, Brigham and Women’s Hospital, Harvard Medical School, Boston, MA, USA
| | - Brittany N. Weber
- Heart and Vascular Center, Division of Cardiovascular Medicine, Department of Medicine, Brigham and Women’s Hospital, Harvard Medical School, Boston, MA, USA
- Cardiovascular Imaging Program, Departments of Medicine and Radiology, Brigham and Women’s Hospital, Harvard Medical School, Boston, MA, USA
| | - Yihe Yang
- Department of Pathology, Brigham and Women’s Hospital, Harvard Medical School, Boston, MA, USA
- Department of Pathology, Donald and Barbara Zucker School of Medicine at Hofstra/Northwell Health, Manhasset, NY, USA
| | - Laurel Martell
- Cardiovascular Imaging Program, Departments of Medicine and Radiology, Brigham and Women’s Hospital, Harvard Medical School, Boston, MA, USA
| | - Anna Perillo
- Cardiovascular Imaging Program, Departments of Medicine and Radiology, Brigham and Women’s Hospital, Harvard Medical School, Boston, MA, USA
| | - Leanne Barrett
- Cardiovascular Imaging Program, Departments of Medicine and Radiology, Brigham and Women’s Hospital, Harvard Medical School, Boston, MA, USA
| | - Sean Parks
- Cardiovascular Imaging Program, Departments of Medicine and Radiology, Brigham and Women’s Hospital, Harvard Medical School, Boston, MA, USA
| | - Jon Hainer
- Cardiovascular Imaging Program, Departments of Medicine and Radiology, Brigham and Women’s Hospital, Harvard Medical School, Boston, MA, USA
| | - Sharmila Dorbala
- Heart and Vascular Center, Division of Cardiovascular Medicine, Department of Medicine, Brigham and Women’s Hospital, Harvard Medical School, Boston, MA, USA
- Cardiovascular Imaging Program, Departments of Medicine and Radiology, Brigham and Women’s Hospital, Harvard Medical School, Boston, MA, USA
| | - Ron Blankstein
- Heart and Vascular Center, Division of Cardiovascular Medicine, Department of Medicine, Brigham and Women’s Hospital, Harvard Medical School, Boston, MA, USA
- Cardiovascular Imaging Program, Departments of Medicine and Radiology, Brigham and Women’s Hospital, Harvard Medical School, Boston, MA, USA
| | - Marcelo F. Di Carli
- Heart and Vascular Center, Division of Cardiovascular Medicine, Department of Medicine, Brigham and Women’s Hospital, Harvard Medical School, Boston, MA, USA
- Cardiovascular Imaging Program, Departments of Medicine and Radiology, Brigham and Women’s Hospital, Harvard Medical School, Boston, MA, USA
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Weber B, Wallace ZS, Parks S, Cook C, Huck DM, Garshick M, Brown JM, Divakaran S, Hainer J, Dorbala S, Blankstein R, Liao KP, Aghayev A, Choi HK, Di Carli M. Association Between Systemic Vasculitis and Coronary Microvascular Dysfunction in the Absence of Obstructive Coronary Artery Disease. Circ Cardiovasc Imaging 2023; 16:e014940. [PMID: 36649456 PMCID: PMC9999265 DOI: 10.1161/circimaging.122.014940] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
Affiliation(s)
- Brittany Weber
- Division of Cardiovascular Medicine, Department of Medicine, Heart and Vascular Center, Brigham and Women's Hospital, Harvard Medical School, Boston, MA (B.W., D.M.H., J.M.B., S. Divakaran, S. Dorbala, R.B., M.D.C)
| | - Zachary S Wallace
- Division of Rheumatology, Allergy, and Immunology Massachusetts General Hospital, Boston (Z.S.W., C.C., H.K.C.)
| | - Sean Parks
- Department of Radiology (S.P., J.H., A.A., M.D.C.), Brigham and Women's Hospital, Boston, MA
| | - Claire Cook
- Division of Rheumatology, Allergy, and Immunology Massachusetts General Hospital, Boston (Z.S.W., C.C., H.K.C.)
| | - Daniel M Huck
- Division of Cardiovascular Medicine, Department of Medicine, Heart and Vascular Center, Brigham and Women's Hospital, Harvard Medical School, Boston, MA (B.W., D.M.H., J.M.B., S. Divakaran, S. Dorbala, R.B., M.D.C)
| | - Michael Garshick
- Center for the Prevention of Cardiovascular Disease, Department of Medicine, New York University School of Medicine (M.G.)
| | - Jenifer M Brown
- Division of Cardiovascular Medicine, Department of Medicine, Heart and Vascular Center, Brigham and Women's Hospital, Harvard Medical School, Boston, MA (B.W., D.M.H., J.M.B., S. Divakaran, S. Dorbala, R.B., M.D.C)
| | - Sanjay Divakaran
- Division of Cardiovascular Medicine, Department of Medicine, Heart and Vascular Center, Brigham and Women's Hospital, Harvard Medical School, Boston, MA (B.W., D.M.H., J.M.B., S. Divakaran, S. Dorbala, R.B., M.D.C)
| | - Jon Hainer
- Department of Radiology (S.P., J.H., A.A., M.D.C.), Brigham and Women's Hospital, Boston, MA
| | - Sharmila Dorbala
- Division of Cardiovascular Medicine, Department of Medicine, Heart and Vascular Center, Brigham and Women's Hospital, Harvard Medical School, Boston, MA (B.W., D.M.H., J.M.B., S. Divakaran, S. Dorbala, R.B., M.D.C)
| | - Ron Blankstein
- Division of Cardiovascular Medicine, Department of Medicine, Heart and Vascular Center, Brigham and Women's Hospital, Harvard Medical School, Boston, MA (B.W., D.M.H., J.M.B., S. Divakaran, S. Dorbala, R.B., M.D.C)
| | - Katherine P Liao
- Division of Rheumatology, Immunology and Allergy (K.P.L.), Brigham and Women's Hospital, Boston, MA
| | - Ayaz Aghayev
- Department of Radiology (S.P., J.H., A.A., M.D.C.), Brigham and Women's Hospital, Boston, MA
| | - Hyon K Choi
- Division of Rheumatology, Allergy, and Immunology Massachusetts General Hospital, Boston (Z.S.W., C.C., H.K.C.)
| | - Marcelo Di Carli
- Division of Cardiovascular Medicine, Department of Medicine, Heart and Vascular Center, Brigham and Women's Hospital, Harvard Medical School, Boston, MA (B.W., D.M.H., J.M.B., S. Divakaran, S. Dorbala, R.B., M.D.C).,Department of Radiology (S.P., J.H., A.A., M.D.C.), Brigham and Women's Hospital, Boston, MA
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Weber B, Parks S, Huck DM, Kim A, Bay C, Brown JM, Divakaran S, Hainer J, Bibbo C, Taqueti V, Dorbala S, Blankstein R, Woolley AE, Di Carli MF. Prior SARS-CoV-2 Infection Is Associated With Coronary Vasomotor Dysfunction as Assessed by Coronary Flow Reserve From Cardiac Positron Emission Tomography. J Am Heart Assoc 2022; 11:e025844. [PMID: 36250654 PMCID: PMC9673657 DOI: 10.1161/jaha.122.025844] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Background Cardiovascular complications from COVID-19 contribute to its high morbidity and mortality. The effect of COVID-19 infection on the coronary vasculature is not known. The objective of this study was to investigate the prevalence of coronary vasomotor dysfunction identified by coronary flow reserve from cardiac positron emission tomography in patients with previous COVID-19 infection. Methods and Results All patients who had polymerase chain reaction-confirmed SARS-CoV-2 infection referred for myocardial stress perfusion positron emission tomography imaging at Brigham and Women's Hospital from April 2020 to July 2021 were compared with a matched control group without prior SARS-CoV-2 infection imaged in the same period. The main outcome was the prevalence of coronary vasomotor dysfunction. Myocardial perfusion and myocardial blood flow reserve were quantified using N13-ammonia positron emission tomography imaging. Thirty-four patients with prior COVID-19 were identified and compared with 103 matched controls. The median time from polymerase chain reaction-confirmed SARS-CoV-2 to cardiac positron emission tomography was 4.6 months (interquartile range,1.2-5.6 months). There were 16 out of 34 (47%) patients previously hospitalized for COVID-19 infection. Baseline cardiac risk factors were common, and 18 (53%) patients in the COVID-19 group had abnormal myocardial perfusion. Myocardial blood flow reserve was abnormal (<2) in 44.0% of the patients with COVID-19 compared with 11.7% of matched controls (P<0.001). The mean myocardial blood flow reserve was 19.4% lower in patients with COVID-19 compared with control patients (2.00±0.45 versus 2.48±0.47, P<0.001). Conclusions Myocardial blood flow reserve was impaired in patients with prior COVID-19 infection compared with cardiovascular risk factor-matched controls, suggesting a relationship between SARS-CoV-2 infection and coronary vascular health. These data highlight the need to assess long-term consequences of COVID-19 on vascular health in future prospective studies.
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Affiliation(s)
- Brittany Weber
- Cardiovascular Imaging Program, Departments of Medicine and RadiologyBrigham and Women’s Hospital, Harvard Medical SchoolBostonMA,Cardiovascular Division, Department of MedicineBrigham and Women’s Hospital, Harvard Medical SchoolBostonMA
| | - Sean Parks
- Cardiovascular Imaging Program, Departments of Medicine and RadiologyBrigham and Women’s Hospital, Harvard Medical SchoolBostonMA,Cardiovascular Division, Department of MedicineBrigham and Women’s Hospital, Harvard Medical SchoolBostonMA
| | - Daniel M. Huck
- Cardiovascular Imaging Program, Departments of Medicine and RadiologyBrigham and Women’s Hospital, Harvard Medical SchoolBostonMA,Cardiovascular Division, Department of MedicineBrigham and Women’s Hospital, Harvard Medical SchoolBostonMA
| | - Andy Kim
- Division of Infectious Disease, Department of MedicineBrigham and Women’s Hospital, Harvard Medical SchoolBostonMA
| | - Camden Bay
- Department of RadiologyBrigham and Women’s Hospital, Harvard Medical SchoolBostonMA
| | - Jenifer M. Brown
- Cardiovascular Imaging Program, Departments of Medicine and RadiologyBrigham and Women’s Hospital, Harvard Medical SchoolBostonMA,Cardiovascular Division, Department of MedicineBrigham and Women’s Hospital, Harvard Medical SchoolBostonMA
| | - Sanjay Divakaran
- Cardiovascular Imaging Program, Departments of Medicine and RadiologyBrigham and Women’s Hospital, Harvard Medical SchoolBostonMA,Cardiovascular Division, Department of MedicineBrigham and Women’s Hospital, Harvard Medical SchoolBostonMA
| | - Jon Hainer
- Cardiovascular Imaging Program, Departments of Medicine and RadiologyBrigham and Women’s Hospital, Harvard Medical SchoolBostonMA,Cardiovascular Division, Department of MedicineBrigham and Women’s Hospital, Harvard Medical SchoolBostonMA
| | - Courtney Bibbo
- Cardiovascular Imaging Program, Departments of Medicine and RadiologyBrigham and Women’s Hospital, Harvard Medical SchoolBostonMA,Cardiovascular Division, Department of MedicineBrigham and Women’s Hospital, Harvard Medical SchoolBostonMA
| | - Viviany Taqueti
- Cardiovascular Imaging Program, Departments of Medicine and RadiologyBrigham and Women’s Hospital, Harvard Medical SchoolBostonMA,Cardiovascular Division, Department of MedicineBrigham and Women’s Hospital, Harvard Medical SchoolBostonMA
| | - Sharmila Dorbala
- Cardiovascular Imaging Program, Departments of Medicine and RadiologyBrigham and Women’s Hospital, Harvard Medical SchoolBostonMA,Cardiovascular Division, Department of MedicineBrigham and Women’s Hospital, Harvard Medical SchoolBostonMA
| | - Ron Blankstein
- Cardiovascular Imaging Program, Departments of Medicine and RadiologyBrigham and Women’s Hospital, Harvard Medical SchoolBostonMA,Cardiovascular Division, Department of MedicineBrigham and Women’s Hospital, Harvard Medical SchoolBostonMA
| | - Ann E. Woolley
- Division of Infectious Disease, Department of MedicineBrigham and Women’s Hospital, Harvard Medical SchoolBostonMA
| | - Marcelo F. Di Carli
- Cardiovascular Imaging Program, Departments of Medicine and RadiologyBrigham and Women’s Hospital, Harvard Medical SchoolBostonMA,Cardiovascular Division, Department of MedicineBrigham and Women’s Hospital, Harvard Medical SchoolBostonMA
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Wallace Z, Weber B, Parks S, Cook C, Huck D, Brown J, Divakaran S, Hainer J, Bibbo C, Taqueti V, Dorbala S, Blankenstein R, Liao K, Aghayev A, Choi H, Di Carli M. AB0624 Patients with vasculitis have a high prevalence of coronary microvascular dysfunction. Ann Rheum Dis 2022. [DOI: 10.1136/annrheumdis-2022-eular.2709] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
Abstract
BackgroundVasculitides are a heterogenous group of diseases characterized by intense vessel wall inflammation, endothelial injury, and systemic inflammation. Several vasculitides are associated with high risk of cardiovascular (CV) disease, an important source of morbidity and mortality in this population. This excess CV risk is attributed both to a high burden of traditional risk factors and to inflammation, but this remains poorly studied. Indeed, inflammation is a known risk factor for CV disease and implicated in coronary microvascular dysfunction (CMD) which may precede obstructive coronary artery disease (CAD).ObjectivesWe sought to assess whether vasculitis is associated with CMD in the absence of obstructive CAD.MethodsWe retrospectively identified subjects with systemic vasculitis who underwent symptom prompted rest/stress myocardial perfusion PET. Patients with an abnormal myocardial perfusion study (summed stress score ≥3) or LVEF<40% were excluded. Controls were identified from the same population and matched on age, gender and cardiovascular risk factors (CAD, hypertension, dyslipidemia, diabetes mellitus, and obesity). Coronary flow reserve (CFR), was calculated as the ratio of myocardial blood flow (ml/min/g) at peak stress compared to rest. CMD was defined as CFR <2.ResultsWe studied 26 vasculitis cases and 66 matched controls. The most common vasculitides were giant cell arteritis (38%), ANCA-associated vasculitis (31%), and Takayasu’s arteritis (12%). Median (IQR) time between diagnosis and PET was 6.5 (2.9, 14.2) years. Seven (27%) cases had active vascultis at the time of PET. Cases and controls were well-matched on age, sex, and CV risk factors (Table 1). Despite a similar prevalence of CV risk factors, coronary flow reserve (reflected by CMD) was abnormal in 38% of vasculitis cases compared to 15% of controls (p=0.004). The mean [SD] CFR was 19% lower in vasculitis cases vs controls (2.11 [0.5] versus 2.6 [0.7], p=0.003).Table 1.The presence of coronary microvasculature dysfunction in patients with systemic vasculitis without obstructive coronary artery diseaseCohort characteristicsVasculitis (n=26)Control (n=66)P-valueAge at PET, years62 (18)61 (17)0.24Time from Vasculitis Diagnosis to PET, years (median, IQR)6.5 (2.9, 14.2)n/aFemale, n (%)18 (72%)43 (65%)0.99Vasculitis CharacteristicsLarge Vessel (e.g., giant cell arteritis, Takayasu’s), n(%)13 (50%)n/an/aMedium Vessel (e.g., polyarteritis nodosa, Kawasaki’s arteritis), n(%)2 (8%)n/an/aSmall Vessel (e.g., ANCA-associated vasculitis, Henoch-Schonlein Purpura), n(%)11 (42%)n/an/aCardiovascular Risk FactorsAt DiagnosisAt PETAt PETHypertension, n (%)12 (46%)20 (71%)47 (80%)0.47Obesity, n (%)3 (12%)2 (32%)2 (32%)0.84Diabetes, n (%)3 (12%)5 (20%)13 (20%)0.99Dyslipidemia, n (%)4 (15%)15 (58%)40 (61%)0.99Known CAD, n (%)0 (0%)1 (4%)1 (2%)0.48Imaging FindingsRest myocardial blood flow, ml/min/g1.0 (0.3)1.0 (0.3)0.8Stress myocardial blood flow, ml/min/g2.1 (0.6)2.6 (1.0)0.008Coronary Flow Reserve, ml/min/g*2.1 (0.5)2.6 (0.7)0.003Coronary Microvasculature Dysfunction** (CMD), n (%)10 (38%)11 (15%)0.004ConclusionPatients with systemic vasculitis, even in the absence of obstructive CAD, have a high prevalence of CMD compared with non-vasculitis patients. These differences were observed despite matching cases and controls on traditional CV risk factors, highlighting the importance of other factors, such as inflammation and vasculitis treatments on CMD and CV disease in this population. CMD is a known independent risk factor for CV mortality. Future prospective studies are needed to understand the relationship between vasculitis, systemic inflammation, and CMD.Disclosure of InterestsNone declared
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Parks S, Hoffman MK, Goudar SS, Patel A, Saleem S, Ali SA, Goldenberg RL, Hibberd PL, Moore J, Wallace D, McClure EM, Derman RJ. Maternal anaemia and maternal, fetal, and neonatal outcomes in a prospective cohort study in India and Pakistan. BJOG 2019; 126:737-743. [PMID: 30554474 DOI: 10.1111/1471-0528.15585] [Citation(s) in RCA: 56] [Impact Index Per Article: 11.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 12/06/2018] [Indexed: 11/29/2022]
Abstract
OBJECTIVE To describe the association of maternal anaemia with maternal, fetal, and neonatal outcomes. DESIGN Prospective cohort study. SETTING Rural India and Pakistan. POPULATION Pregnant women residing in the study catchment area. METHODS We performed an analysis of a prospective pregnancy registry in which haemoglobin is commonly obtained as well as maternal, fetal, and neonatal outcomes for 42 days post-delivery. Women 40 years or older who delivered before 20 weeks or had a haemoglobin level of <3.0 g/dl were excluded. Our primary exposure was maternal anaemia, which was categorised in keeping with World Health Organization criteria based on a normal (≥11 g/dl), mild (>10-10.9 g/dl), moderate (7-9.9 g/dl) or severe (<7 g/dl). haemoglobin level. The primary maternal outcome was maternal death, the primary fetal outcome was stillbirth, and the primary neonatal outcome was neonatal mortality <28 days. RESULTS A total of 92 247 deliveries and 93 107 infants were included, of which 87.8% were born to mothers who were anaemic (mild 37.9%, moderate 49.1%, and severe 0.7%). Maternal mortality (number per 100 000) was not associated with anaemia: normal 124, mild 106, moderate 135, and severe 325 (P = 0.64). Fetal and neonatal mortality was associated with severe anaemia: stillbirth rate (n/1000)-normal 27.7, mild 25.8, moderate 30.1, and severe 90.9; P < 0.0001; 28-day neonatal mortality (n/1000)-normal 24.7, mild 22.9, moderate 28.1, and severe 72.6 (P < 0.0001). Severe maternal anaemia was also associated with low birthweight (<2500 and <1500 g), preterm birth, and postpartum haemorrhage. CONCLUSION Severe maternal anaemia is associated with higher risks of poor maternal, fetal, and neonatal outcomes but other degrees of anaemia are not. Interventions directed at preventing severe anaemia in pregnant women should be considered. TWEETABLE ABSTRACT Severe maternal anaemia is associated with adverse fetal and neonatal outcomes in low/middle-income countries.
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Affiliation(s)
- S Parks
- Department of Obstetrics & Gynecology, Christiana Care Health System, Newark, DE, USA
| | - M K Hoffman
- Department of Obstetrics & Gynecology, Christiana Care Health System, Newark, DE, USA
| | - S S Goudar
- KLE Academy of Higher Education and Research, Belgaum, India
| | - A Patel
- Lata Medical Research Foundation, Nagpur, India
| | - S Saleem
- Department of Community Health Sciences, Aga Khan University, Karachi, Pakistan
| | - S A Ali
- Department of Community Health Sciences, Aga Khan University, Karachi, Pakistan
| | - R L Goldenberg
- Department of Obstetrics and Gynecology, Columbia University, New York, NY, USA
| | - P L Hibberd
- Department of Global Health, Boston University School of Public Health, Boston, MA, USA
| | - J Moore
- RTI International, Research Triangle Park, NC, USA
| | - D Wallace
- RTI International, Research Triangle Park, NC, USA
| | - E M McClure
- RTI International, Research Triangle Park, NC, USA
| | - R J Derman
- Thomas Jefferson University, Philadelphia, PA, USA
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Walker J, Moore G, Collins S, Parks S, Garvey MI, Lamagni T, Smith G, Dawkin L, Goldenberg S, Chand M. Microbiological problems and biofilms associated with Mycobacterium chimaera in heater-cooler units used for cardiopulmonary bypass. J Hosp Infect 2017; 96:209-220. [PMID: 28532976 DOI: 10.1016/j.jhin.2017.04.014] [Citation(s) in RCA: 55] [Impact Index Per Article: 7.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2017] [Accepted: 04/19/2017] [Indexed: 01/21/2023]
Abstract
The role of heater-cooler units (HCUs) in the transmission of Mycobacterium chimaera during open heart surgery has been recognized since 2013. Subsequent investigations uncovered a remarkable global outbreak reflecting the wide distribution of implicated devices. HCUs are an essential component of cardiopulmonary bypass operations and their withdrawal would severely affect capacity for life-saving cardiac surgery. However, studies have demonstrated that many HCUs are contaminated with a wide range of micro-organisms, including M. chimaera and complex biofilms. Whole genome sequencing of M. chimaera isolates recovered from one manufacturer's HCUs, worldwide, has demonstrated a high level of genetic similarity, for which the most plausible hypothesis is a point source contamination of the devices. Dissemination of bioaerosols through breaches in the HCU water tanks is the most likely route of transmission and airborne bacteria have been shown to have reached the surgical field even with the use of ultraclean theatre ventilation. Controlling the microbiological quality of the water circulating in HCUs and reducing biofilm formation has been a major challenge for many hospitals. However, enhanced decontamination strategies have been recommended by manufacturers, and, although they are not always effective in eradicating M. chimaera from HCUs, UK hospitals have not reported any new cases of M. chimaera infection since implementing these mitigation strategies. Water safety groups in hospitals should be aware that water in medical devices such as HCUs may act as a vector in the transmission of potentially fatal water-borne infections.
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Affiliation(s)
- J Walker
- Biosafety, Air and Water Microbiology Group, National Infection Service, Public Health England, Porton Down, Salisbury, UK.
| | - G Moore
- Biosafety, Air and Water Microbiology Group, National Infection Service, Public Health England, Porton Down, Salisbury, UK
| | - S Collins
- Biosafety, Air and Water Microbiology Group, National Infection Service, Public Health England, Porton Down, Salisbury, UK
| | - S Parks
- Biosafety, Air and Water Microbiology Group, National Infection Service, Public Health England, Porton Down, Salisbury, UK
| | - M I Garvey
- Infection Prevention and Control Team, University Hospitals Birmingham NHS Foundation Trust, Queen Elizabeth Hospital Birmingham, Mindelsohn Way, Edgbaston, Birmingham, UK
| | - T Lamagni
- Healthcare-Associated Infection & Antimicrobial Resistance Department, National Infection Service, Public Health England, Colindale, London, UK
| | - G Smith
- Public Health England National Mycobacterial Reference Service, Birmingham Public Health Laboratory, Birmingham, UK
| | - L Dawkin
- Estates and Facilities, University Hospitals Coventry and Warwickshire NHS Trust, Walsall, UK
| | - S Goldenberg
- Centre for Clinical Infection and Diagnostics Research, King's College, London and Guy's & St Thomas' NHS Foundation Trust, London, UK
| | - M Chand
- Reference Microbiology, National Infection Service, Public Health England, Colindale, London, UK; Guy's & St Thomas' NHS Foundation Trust, London, UK; National Institute for Health Research, Health Protection Research Unit in Respiratory Infections, Imperial College, London, UK
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Cormerais Y, Giuliano S, Massard P, Durivault J, Hitoshi E, Michael W, Parks S, Pouyssegur J. Dissecting the pro-tumoural role of the essential amino-acid transporter complex CD98/LAT1. Eur J Cancer 2016. [DOI: 10.1016/s0959-8049(16)61253-4] [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: 11/26/2022]
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11
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Walker J, Jhutty A, Parks S, Willis C, Copley V, Turton J, Hoffman P, Bennett A. Investigation of healthcare-acquired infections associated with Pseudomonas aeruginosa biofilms in taps in neonatal units in Northern Ireland. J Hosp Infect 2014; 86:16-23. [DOI: 10.1016/j.jhin.2013.10.003] [Citation(s) in RCA: 71] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/15/2013] [Accepted: 10/03/2013] [Indexed: 11/25/2022]
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Jones RM, Ashford R, Cork J, Palmer S, Wood E, Spyvee P, Parks S, Bennett A, Brewer J, Delahay R, Chambers M, Sawyer J. Evaluation of a method to detect Mycobacterium bovis in air samples from infected Eurasian badgers (Meles meles) and their setts. Lett Appl Microbiol 2013; 56:361-5. [PMID: 23384280 DOI: 10.1111/lam.12055] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/23/2012] [Revised: 01/24/2013] [Accepted: 01/31/2013] [Indexed: 11/29/2022]
Abstract
Environmental air sampling was evaluated as a method to detect the presence of M. bovis in the vicinity of infected badgers and their setts. Airborne particles were collected on gelatine filters using a commercially available air sampling instrument and tested for the presence of M. bovis using bacteriological culture and real-time PCR. The sensitivity of bacteriological culture was broadly similar to that of real-time PCR when testing samples artificially spiked with M. bovis. Sampling was undertaken from directly under the muzzles of badgers which had been experimentally infected with M. bovis (37 samples), within enclosures housing the experimentally infected animals (50 samples), and in the vicinity of setts with resident infected wild badgers (52 samples). The methods employed did not detect M. bovis from either infected badgers or artificial or natural setts known to contain infected animals. However, samples taken at four of the six natural setts were positive for Mycobacterium gordonae.
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Affiliation(s)
- R M Jones
- Animal Health and Veterinary Laboratories Agency Weybridge, Addlestone, UK
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Doyen J, Parks S, Courdi A, Marcié S, Pouysségur J, Chiche J, Angellier G, Poudenx M. Efficacité et toxicité d’une réirradiation stéréotaxique ablative dans les cancers bronchiques pulmonaires non à petites cellules en récidive locale. Cancer Radiother 2012. [DOI: 10.1016/j.canrad.2012.07.052] [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: 10/27/2022]
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14
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Niederkrotenthaler T, Xu L, Parks S, Sugerman D. Risk Factors for Abusive Head Trauma in Young Children — United States, 2000–2009. Ann Epidemiol 2012. [DOI: 10.1016/j.annepidem.2012.06.079] [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: 11/29/2022]
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15
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Thompson K, Thomson G, Mittal H, Parks S, Dove B, Speight S, Walker J, Pappachan J, Hoffman P, Bennett A. FP3.2 Transmission of influenza to health-care workers in intensive care units – could Aerosol generating procedures play a role? J Hosp Infect 2010. [DOI: 10.1016/s0195-6701(10)60017-5] [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: 10/19/2022]
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16
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Agarwal P, Dudgeon S, Parks S, Keating D, Wykes W. Effect of intravitreal bevacizumab (Avastin®) in the fellow eye of a patient with bilateral exudative age related macular degeneration. Scott Med J 2010. [DOI: 10.1258/rsmsmj.55.2.58c] [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: 11/18/2022]
Affiliation(s)
- P.K Agarwal
- Southern General Hospital, Glasgow, United Kingdom
| | - S Dudgeon
- Tennent Institute of Ophthalmology, Gartnavel General Hospital, Glasgow, United Kingdom
| | - S Parks
- Tennent Institute of Ophthalmology, Gartnavel General Hospital, Glasgow, United Kingdom
| | - D Keating
- Tennent Institute of Ophthalmology, Gartnavel General Hospital, Glasgow, United Kingdom
| | - W Wykes
- Southern General Hospital, Glasgow, United Kingdom
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Goss G, Tresguerres M, Parks S. Theoretical considerations underlying Na+ uptake mechanisms in freshwater fishes. Comp Biochem Physiol A Mol Integr Physiol 2008. [DOI: 10.1016/j.cbpa.2008.04.215] [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: 11/16/2022]
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Abstract
AIM To quantify microbial aerosols generated by a series of laboratory accidents and to use these data in risk assessment. METHODS AND RESULTS A series of laboratory accident scenarios have been devised and the microbial aerosol generated by them has been measured using a range of microbial air samplers. The accident scenarios generating the highest aerosol concentrations were, dropping a fungal plate, dropping a large bottle, centrifuge rotor leaks and a blocked syringe filter. Many of these accidents generated low particle size aerosols, which would be inhaled into the lungs of any exposed laboratory staff. Spray factors (SFs) have been calculated using the results of these experiments as an indicator of the potential for accidents to generate microbial aerosols. Model risk assessments have been described using the SF data. CONCLUSIONS Quantitative risk assessment of laboratory accidents can provide data that can aid the design of containment laboratories and the response to laboratory accidents. SIGNIFICANCE AND IMPACT OF THE STUDY A methodology has been described and supporting data provided to allow microbiological safety officers to carry out quantitative risk assessment of laboratory accidents.
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Affiliation(s)
- A Bennett
- Centre for Emergency Preparedness and Response, Health Protection Agency, Porton Down, Salisbury, UK.
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19
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Keating D, Parks S. CS10.2 Multifocal ERG in assessment of retinal disorders. Clin Neurophysiol 2006. [DOI: 10.1016/j.clinph.2006.07.035] [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: 10/24/2022]
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20
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Griffiths WD, Bennett A, Speight S, Parks S. Determining the performance of a commercial air purification system for reducing airborne contamination using model micro-organisms: a new test methodology. J Hosp Infect 2005; 61:242-7. [PMID: 16009462 DOI: 10.1016/j.jhin.2005.03.004] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2005] [Accepted: 03/03/2005] [Indexed: 10/25/2022]
Abstract
The performance of a duct-mounted air disinfection system, designed to reduce airborne pathogens in the hospital environment, was determined using a new testing methodology. The methodology places the equipment in a test duct, a microbial aerosol is generated and then sampled simultaneously before and after the test system. This allows a percentage efficiency value to be calculated. The air disinfection system is a novel chemical-coated filter and ultraviolet (UV) radiation air purification system, operating at a flow rate of 500 m(3)/h, against aerosols of MS2 phage and Mycobacterium vaccae (surrogates of viral and mycobactericidal pathogens). A three UV lamp system was effective against airborne phages, removing an average of 97.34% of the aerosolized challenge. With the UV component switched off, the average efficiency dropped to 61.46%. This demonstrates that the chemical-coated filter component plays a more significant role than the UV radiation in destroying phages. When six UV lamps were used, the system was able to remove mycobacteria with an efficiency exceeding 99.99%. This test methodology can be used to assess manufacturers' claims of efficacy of equipment against airborne micro-organisms in the hospital environment.
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Affiliation(s)
- W D Griffiths
- Airborne Matters, 47 Manor Road, Toddington, Dunstable LU5 6AJ, UK.
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Chisholm JA, Williams G, Spence E, Parks S, Keating D, Gavin M, Mills PR. Retinal toxicity during pegylated alpha-interferon therapy for chronic hepatitis C: a multifocal electroretinogram investigation. Aliment Pharmacol Ther 2005; 21:723-32. [PMID: 15771758 DOI: 10.1111/j.1365-2036.2005.02365.x] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.1] [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: 12/28/2022]
Abstract
BACKGROUND Ocular side-effects in the form of retinal ischaemia and haemorrhages have been reported in patients undergoing standard alpha-interferon therapy. AIM To assess the ocular impact of therapy with sustained release pegylated alpha-2a interferon (Pegasys) for chronic hepatitis C. METHODS Ten patients receiving Pegasys and ribavirin and 10 healthy volunteers were recruited. Patients underwent full ophthalmic investigations and multifocal electroretinogram testing at baseline, at regular intervals during treatment and post-treatment. The multifocal electroretinogram maps retinal function. Responses were compared with sequential recordings from healthy volunteers. RESULTS All patients had normal clinical ophthalmic investigations at baseline. During therapy a single patient experienced central visual disturbance lasting 24 h with no prolonged ill effect. No other patient was aware of any change in vision. Fundal abnormalities appeared in five patients during treatment. The multifocal electroretinogram showed reductions in retinal function in five patients. Nine of 10 patients exhibited abnormalities on at least one multifocal electroretinogram or fundoscopic investigation. CONCLUSIONS Subclinical retinal toxicity during anti-viral therapy with pegylated alpha-interferon and ribavirin was frequent in this study and it suggests that patients should be warned of this risk and monitored during therapy.
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Affiliation(s)
- J A Chisholm
- Department of Clinical Physics and Bioengineering, Gartnavel General Hospital, Glasgow G12 0YN, UK.
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Abstract
This is an investigation of the effect of changing the pupil diameter on the P1 amplitude and latency of the multifocal electroretinogram (mfERG). MfERGs were recorded using a custom built wide field electrophysiological system. An array of 61 empirically scaled hexagons was used to stimulate the visual field. The duration of overall recording period was 8 min, segmented into 16 intervals each lasting 30 s. A combination of mydriatics and miotics were used to pharmacologically alter the pupil size and diameters between 1 and 10 mm were measured. There was a reduction in mfERG P1 amplitude in some cases greater than 50% (mfERG P1 amplitude 53 nV at 8 mm to 25 nV at 1 mm), with a change in pupil diameter of 7 mm. The mfERG P1 latency increased in some cases by as much as 8 ms in the central 40 degrees (mfERG P1 latency 39 ms at 8 mm to 47 ms at 1 mm). These results suggest that pupil size has significant effects on mfERG P1 amplitude and latency.
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Affiliation(s)
- P Gonzalez
- Electrodiagnostic Imaging Unit, Tennent Institute of Ophthalmology, Gartnavel General Hospital, Glasgow, Scotland, UK
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Muscat S, Parks S, Kemp E, Keating D. Secondary retinal changes associated with choroidal naevi and melanomas documented by optical coherence tomography. Br J Ophthalmol 2004; 88:120-4. [PMID: 14693788 PMCID: PMC1771938 DOI: 10.1136/bjo.88.1.120] [Citation(s) in RCA: 54] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
AIMS To establish the characteristics of secondary retinal changes associated with the presence of choroidal melanomas and choroidal naevi as documented by optical coherence tomography (OCT). METHODS Twenty patients with untreated choroidal melanoma and 40 patients with presumed choroidal naevi managed by regular observation were included in the study. OCT scans across the surface of the tumour and surrounding tissue were acquired for all participants. The appearance of retinal tissue on the OCT scans was considered to be abnormal if it did not display the well defined band structure characteristic of normal tissue on OCT scans. RESULTS Serous retinal detachments were observed in all patients with choroidal melanoma and 18 out of 20 also had abnormal retinal structure or intra-retinal splitting in the tissue overlying the tumour. Out of the 40 patients with presumed choroidal naevi, 12 had serous detachments and three had either abnormal retinal structure or intra-retinal splitting overlying the lesion. CONCLUSIONS Secondary retinal changes associated with choroidal lesions can be documented by OCT. These changes were observed in most patients with choroidal melanoma included in the study group but were far less prevalent in the patients with presumed choroidal naevi. OCT is also able to identify the presence of small serous detachments before they become clinically visible. Follow up of these patients is required to determine whether the OCT results may be of use in the differential diagnosis of small choroidal lesions.
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Affiliation(s)
- S Muscat
- Tennent Institute of Ophthalmology, Gartnavel General Hospital, 1053 Great Western Road, Glasgow G12 0YN, Scotland, UK
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McDonagh J, Stephen LJ, Dolan FM, Parks S, Dutton GN, Kelly K, Keating D, Sills GJ, Brodie MJ. Peripheral retinal dysfunction in patients taking vigabatrin. Neurology 2004; 61:1690-4. [PMID: 14694031 DOI: 10.1212/01.wnl.0000098938.80082.25] [Citation(s) in RCA: 45] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Abstract
OBJECTIVE To assess the wide-field multifocal electroretinogram (WF-mfERG) for assessment of retinal function in vigabatrin-treated patients. METHODS Thirty-two adults who had taken vigabatrin for at least 3 years for localization-related epilepsy underwent WF-mfERG, ERG, logMar visual acuity and color vision evaluation, Humphrey visual field analysis (static perimetry), and funduscopy. The group was matched with a cohort of patients who had never received vigabatrin. Results were compared with a normative data set (120 drug-free controls) with respect to potential bilateral abnormalities in response timing. RESULTS There were no significant differences between groups in visual acuity or color vision testing. Of the vigabatrin patients, 19 (59%) had bilateral visual field defects compared to none of the controls. Using WF-mfERG, all patients on vigabatrin with visual field defects showed abnormalities (100% sensitivity) and only 2 of the 13 patients without a field defect showed retinal abnormalities (86% specificity). CONCLUSIONS WF-mfERG may be useful for detecting retinal pathology in patients taking vigabatrin. The majority of previous reports based on subjective testing may have underestimated the prevalence of peripheral retinal toxicity related to the drug.
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Affiliation(s)
- J McDonagh
- Tennent Institute of Ophthalmology, Gartnavel General Hospital, Glasgow G12 0YN, Scotland
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Affiliation(s)
- F M Dolan
- Ophthalmology Department, Tennent Institute of Ophthalmology, Gartnavel General Hospital, Great Western Road, Glasgow G12 0YN, UK
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Ireland JM, Keating D, Hoggar SG, Parks S. Identification of appropriate primitive polynomials to avoid cross-contamination in multifocal electroretinogram responses. Med Biol Eng Comput 2002; 40:471-8. [PMID: 12227635 DOI: 10.1007/bf02345081] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
Abstract
Abstract-The basis of the multifocal/electroretinogram is the use of a decimated m-sequence for simultaneous and independent stimulation of many areas of the visual pathway. The purpose of this study was to investigate the effects of cross-contamination from higher orders of the response. A series of primitive polynomials were found by construction of finite fields. The first-order ERG response was formed by cross-correlation of m-sequence with the physiological response. A second-order response was formed by investigation of particular flash sequences of the stimulation sequence and cross-correlation of a second-order m-sequence with the physiological response. Zech logarithms were used to identify cross-contamination between the various first and second-order sequences. Tables of good and bad primitive polynomials were constructed for degrees 12-16, and the effects of window length and decimation length were examined. When the sequence was decimated into 128 areas, and a window of length 16 was examined, cross-contamination occurred in all sequences generated from primitive polynomials of degree less than or equal to 12, but in only 26% of degree 14, and 5.6% of degree 16. A photodiode (artificial eye) was used in an experiment to construct trace arrays showing responses from 61 individual areas. Additional waveforms were present on the trace array when the experiment was carried out with a bad primitive polynomial. The use of finite field theory to generate primitive polynomials and Zech logarithm analysis allowed prediction of which primitive polynomials were suitable for m-sequence generation for multifocal electroretinography. Practical investigations supported the theoretical analysis. This has important implications for developers of multifocal electrophysiology systems.
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Affiliation(s)
- J M Ireland
- Department of Mathematics, University of Glasgow, Scotland.
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Abstract
The multifocal ERG technique is a powerful method of studying the function of different areas of the retina. Display systems such as the CRT, which are commonly used for stimulation, are subject to limitations such as those imposed by the raster method of scanning. This work describes a novel stimulating display using LEDs that retains the established hexagonal areas but overcomes some of the limitations of the CRT display systems. The design and construction of the instrument is described together with some preliminary results.
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Affiliation(s)
- D C Smith
- Department of Clinical Physics, Southern General Hospital, Glasgow G51 4TF
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Dolan FM, Parks S, Hammer H, Keating D. The wide field multifocal electroretinogram reveals retinal dysfunction in early retinitis pigmentosa. Br J Ophthalmol 2002; 86:480-1. [PMID: 11914231 PMCID: PMC1771092 DOI: 10.1136/bjo.86.4.480] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
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Muscat S, Fahad B, Parks S, Keating D. Optical coherence tomography and multifocal electroretinography of X-linked juvenile retinoschisis. Eye (Lond) 2001; 15:796-9. [PMID: 11827010 DOI: 10.1038/eye.2001.257] [Citation(s) in RCA: 21] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022] Open
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Muscat S, Srinivasan S, Sampat V, Kemp E, Parks S, Keating D. Optical coherence tomography in the diagnosis of subclinical serous detachment of the macula secondary to a choroidal nevus. Ophthalmic Surg Lasers 2001; 32:474-6. [PMID: 11725771] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/22/2023]
Abstract
We present a case in which optical coherence tomography (OCT) aided in the diagnosis of subretinal fluid (SRF) secondary to a choroidal nevus. A patient with a raised lesion above the left optic disc and distorted central vision was referred to our unit because of suspected choroidal melanoma. Fundus fluorescein angiography and slit-lamp investigation did not indicate any areas of SRF; however, OCT showed serous detachment in the macular area. The lesion was treated with laser photocoagulation and, when reviewed at four weeks post-treatment, repeat OCT scans showed that the area of SRF had cleared. In this case OCT was able to detect a subclinical serous detachment in the macula. This may have important implications in the monitoring of patients with small suspicious lesions.
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Affiliation(s)
- S Muscat
- Electrodiagnostic Imaging Unit, Tennent Institute of Ophthalmology Gartnavel General Hospital, Glasgow, Scotland
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Weir CR, Cleary M, Parks S, Barrie T, Hammer HM, Murdoch J. Spatial localization after different types of retinal detachment surgery. Invest Ophthalmol Vis Sci 2001; 42:1495-8. [PMID: 11381052] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/20/2023] Open
Abstract
PURPOSE To compare the effect on spatial localization of two different forms of surgery for primary rhegmatogenous retinal detachment. METHODS Two groups of 30 patients (one group undergoing conventional external scleral-buckling procedures, the other undergoing vitrectomy procedures) were recruited. They pointed at targets appearing on a computer touchscreen without being able to see their hands, while viewing targets with the non-surgically treated eye. The sizes of the horizontal pointing errors were recorded on three separate occasions: before surgery, on the first postoperative day, and approximately 10 days later. RESULTS On the first postoperative day a significant change in localization of 2.9 +/- 0.9 degrees [SD]) was observed in the scleral-buckling group, compared with 1.3 +/- 0.6 degrees in the vitrectomy group. These changes resolved by the second postoperative assessment. CONCLUSIONS These results, particularly in patients in the scleral-buckling group in whom greater manipulation of the extraocular muscles inevitably occurs, are consistent with an alteration in the extraretinal eye position information that is used in spatial localization. This is likely to be a consequence of modified efference copy and/or extraocular muscle proprioception.
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Affiliation(s)
- C R Weir
- Tennent Institute of Ophthalmology and the. Department of Orthoptics, Gartnavel General Hospital, Glasgow, Scotland, United Kingdom.
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Abstract
The purpose of this paper is to compare and evaluate the multifocal ERG response from raster based CRT and Digital Projection (LCD) stimulus delivery systems. A custom built p.c. based multifocal system was used to generate a 61 hexagonal element stimulus array. The stimulus was presented on a high luminance CRT display and on a back projected screen using a Digital polysilicon projection system. A fast response photodiode was used to analyse the stimulus pulse characteristics of both systems. A number of recordings were performed to assess the effect of stimulus delivery on a standard m-sequence response, inserted full-field filler response and on separation of onset and offset components. The pulse width for a CRT system is dependant on the type of phosphor and is typically 2 msec whereas the Digital Projection system produces a 13.3 msec pulse equivalent to the frame rate for the system. Slowing down the m-sequence by a factor of eight results in a pulse width of 106 msec which should enable the recovery of true offset responses. The CRT stimulus consists of a series of eight pulses of 2 msec duration each separated by 11.3 msec. First order responses are larger from the CRT system and second order responses larger from the Digital system. In conclusion, there are fundamental differences in the two delivery systems. The CRT system may have more potential in examining non-linear aspects of the multifocal response. Although both systems may be able to record offset responses, the Digital system will generate true offset responses whereas the CRT system may not allow true separation of these components.
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Affiliation(s)
- D Keating
- ElectroDiagnostic Imaging Unit, Tennent Institute of Ophthalmology, Gartnavel General Hospital, Glasgow, Scotland, UK.
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Abstract
There are a number of variables which can influence the quality of multifocal ERG waveforms. In common with visual field measurements, fixation quality may be an important parameter on the integrity of the acquired data. A low cost, fixation-monitoring device was used to assess fixation quality on a group of normal volunteers. Data was successfully acquired while five subjects viewed a fixation target for a period of time equal to that of a single multifocal recording segment. The target was presented on a stationary grey background and as the central fixation mark on a 61-element multifocal flicker stimulus. The results show no significant difference with or without the flickering pattern. The percentage of samples falling within 1.2 degrees of the point of fixation was 51%. This suggests that fixation quality is adequate for scaled stimuli where the central element subtends 2.4 degrees. High resolution stimuli of less than 2.4 degrees may be more susceptible to fixation fluctuations during the recording process.
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Affiliation(s)
- J A Chisholm
- Electrodiagnostic Imaging Unit, Tennent Institute of Ophthalmology, Gartnavel General Hospital, Glasgow, Scotland, UK
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Abstract
There are a wide range of variables which can influence the quality of the multifocal response. It is possible to place these variables into one of four categories. First, the method of stimulus delivery will determine the field of view, interference levels and the duration of on-state stimulation. Second, data acquisition variables such as electrode type and placement, amplifier specifications and filter bandwidth settings will have a direct impact on waveform shape and on the topographic distribution of signal amplitudes. Third, patient variables such as fixation, pupil dilation and refractive error will also contribute to the multifocal response. Fourth, there are many measurements that can be taken from multifocal recordings. In addition to standard amplitude and implicit time measures (the implicit time measure in the multifocal response is becoming increasingly important particularly in early stages of disease processes), the scalar product measure provides information on waveform shape. The conventional impulse and higher order responses will be different for different modes of stimulation such as Cathode Ray Tube (CRT) and Liquid Crystal Display (LCD) systems and latency shifts will be introduced if not corrected in software. Procedures which could lead to misleading interpretation include artefact rejection, averaging with neighbours and summing of responses. These procedures should be handled with caution.
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Affiliation(s)
- D Keating
- ElectroDiagnostic Imaging Unit, Tennent Institute of Ophthalmology, Gartnavel General Hospital, Glasgow, Scotland, UK
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McDonagh J, Grierson DJ, Keating D, Parks S. The wide field multifocal ERG reveals a retinal defect caused by vigabatrin toxicity. Br J Ophthalmol 2001; 85:119-20. [PMID: 11201951 PMCID: PMC1723692 DOI: 10.1136/bjo.85.1.110k] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
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Weir CR, Cleary M, Parks S, Dutton GN. Spatial localization in esotropia: does extraretinal eye position information change? Invest Ophthalmol Vis Sci 2000; 41:3782-6. [PMID: 11053277] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/18/2023] Open
Abstract
PURPOSE To investigate the accuracy of spatial localization in children with a specific type of convergent strabismus, fully accommodative esotropia. METHODS Two groups of children, with right and left fully accommodative esotropia, respectively, pointed at targets located centrally and eccentrically on a computer touchscreen without being able to see their hands. The size and the direction of the horizontal pointing responses were recorded under two conditions: when their eyes were aligned (wearing spectacles) and when they were squinting (not wearing spectacles). A group of children without strabismus but with hypermetropia were assessed as controls. RESULTS For both fully accommodative groups, the pointing responses to the central target shifted in the direction of the nonsquinting eye when deviations were manifest. No difference was found for the eccentric targets. No difference was found for the hypermetropia group with any target. CONCLUSIONS These results are consistent with an alteration in the extraretinal eye position information (efference copy, extraocular muscle proprioception, or both) that is used in spatial localization.
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Affiliation(s)
- C R Weir
- Tennent Institute of Ophthalmology, Department of Orthoptics, Gartnavel General Hospital, Glasgow.
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Sparber A, Bauer L, Curt G, Eisenberg D, Levin T, Parks S, Steinberg SM, Wootton J. Use of complementary medicine by adult patients participating in cancer clinical trials. Oncol Nurs Forum 2000; 27:623-30. [PMID: 10833691] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/16/2023]
Abstract
PURPOSE/OBJECTIVES To document the prevalence, demographic correlates, patterns of use, and beliefs about complementary and alternative medicine (CAM) therapies of adult patients enrolled in National Cancer Institute (NCI) clinical trials. DESIGN Prospective, cross-sectional, descriptive survey. SETTING W.G. Magnuson Clinical Center of the National Institutes of Health in Bethesda, MD. SAMPLE Convenience sample of 100 English-speaking, adult patients with cancer admitted to intramural clinical trials. METHODS A standardized, 99-item questionnaire assessing use of CAM therapies pre- and postcancer diagnosis was administered by face-to-face interview. MAIN RESEARCH VARIABLES Use of CAM therapies, beliefs, communication with physician. FINDINGS 63% used at least one CAM therapy, with an average use of two therapies per patient. Men were significantly less likely to use a therapy than women; women were more likely to use numerous therapies. Cancer diagnosis seems to have had no influence overall on the frequency of use of CAM therapies. The major reasons stated for CAM use were for treatment-related medical conditions as well as depression, anxiety, and insomnia. The most frequently reported therapies were spiritual, relaxation, imagery, exercise, lifestyle diet (e.g., macrobiotic, vegetarian), and nutritional supplementation. Patients unanimously believed that these complementary therapies helped to improve their quality of life through more effective coping with stress, decreasing the discomforts of treatment and illness, and giving them a sense of control. CONCLUSIONS Patients with cancer use various complementary therapies to cope with their disease and the rigors of clinical trials. Women and those with higher educational backgrounds were more frequent users. IMPLICATIONS FOR NURSING PRACTICE Nurses who provide care to subjects of biomedical research have an opportunity and responsibility regarding their patients' use of CAM therapies. Nurses may use in-house resources to help evaluate subjects' use of a CAM modality or to provide quality-of-life therapies such as relaxation, imagery, or healing touch. Discussing these health practices in a nonjudgmental manner adds to the assessment of patients' coping skills and ability to make decisions about their health care.
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Affiliation(s)
- A Sparber
- National Institutes of Health (NIH), Bethesda, MD, USA.
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Parks S, Paul DW. Ozone exposure: a case report and discussion. J Okla State Med Assoc 2000; 93:48-51. [PMID: 10692811] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/15/2023]
Abstract
A 45-year-old man working with ozone presents with evidence of sinusitis, mucus membrane irritation, sleep disturbance and shortness of breath. Naturally occurring or manmade, ozone may damage pulmonary alveolar type I cells at significant exposure levels. EPA and OSHA regulate exposure concentrations. Studies show dose responses with exposures. Supporting epidemiological studies are reviewed briefly. Limiting potential for excess exposure is key to prevention. Recognition of ozone as a potential exposure in the Oklahoma workplace is key to symptom management.
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Affiliation(s)
- S Parks
- Occupational and Environmental Medicine Division, University of Oklahoma Health Sciences Center-Oklahoma City, USA
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Job HM, Keating D, Evans AL, Parks S. Three-dimensional electromagnetic model of the human eye: advances towards the optimisation of electroretinographic signal detection. Med Biol Eng Comput 1999; 37:710-9. [PMID: 10723877 DOI: 10.1007/bf02513372] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Classical electromagnetic theory is used to examine the topographical variation in electrical potentials over the corneal surface resulting from specific retinal stimuli. Results from a three-dimensional mathematical model show that over 97% of calculated electromagnetic field potentials lie within 3% of previous analytical model data for an axially symmetric case. Maps of corneal potentials are produced that are shown to be characteristic of specific retinal stimuli and location. The maximum variation in corneal potential for a full field global stimulus is found to be approximately 1%. This is considered encouraging, as current electrophysiology techniques measure ocular potentials from a single corneal or scleral site, the position of which is often difficult to localise and reproduce. The model is used to simulate both central and peripheral stimuli and scotoma conditions. A 20 degrees central scotoma simulation shows an overall reduction in central corneal potential of only 3%, whereas peripheral stimuli are found to cause up to 10% variations in this potential. There is therefore a possibility that a single recording site for multifocal retinal stimulation is not ideal. These data may be used to suggest more appropriate electrode recording positions for maximum signal recovery, not least in optimising signal detection for multi-focal electroretinography stimulation.
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Affiliation(s)
- H M Job
- Tennent Institute of Ophthalmology, Gartnavel General Hospital, Glasgow, Scotland.
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Gomez PS, Parks S, Ries R, Tran TC, Gomez PF, Press RD. Polymorphism in intron 4 of HFE does not compromise haemochromatosis mutation results. Nat Genet 1999; 23:272. [PMID: 10545944 DOI: 10.1038/15723] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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Affiliation(s)
- B Abernethy
- Department of Human Movement Studies, University of Queensland.
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Mangram AJ, Archibald LK, Hupert M, Tokars JI, Silver LC, Brennan P, Arduino M, Peterson S, Parks S, Raymond A, McCullough M, Jones M, Wasserstein A, Kobrin S, Jarvis WR. Outbreak of sterile peritonitis among continuous cycling peritoneal dialysis patients. Kidney Int 1998; 54:1367-71. [PMID: 9767557 DOI: 10.1046/j.1523-1755.1998.00110.x] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
BACKGROUND Approximately 30,000 patients receive peritoneal dialysis in the United States. In August 1996, several dialysis centers from different states reported sterile peritonitis among CCPD patients using sterile peritoneal dialysis solution (PDS) from a single manufacturer. The manufacturer recalled 53 lots of PDS that had passed established industry guidelines and Food and Drug Administration (FDA) approved quality control tests [including endotoxin levels <0.5 endotoxin units (EU)/ml], but had pre-sterilization bacterial colony counts >1 cfu/ml. METHODS At one outpatient dialysis center, Hospital of the University of Pennsylvania (HUP), we conducted a retrospective cohort study of all CCPD patients treated during July 15 to August 30, 1996. A case-patient was defined as any HUP patient with culture-negative peritoneal fluid with a white blood cell count >100/mm3, cloudy peritoneal fluid, and/or abdominal pain. PDS and tubing were cultured for bacteria and assayed for endotoxin. RESULTS Overall, 14 of 28 patients had sterile peritonitis. The only risk factor identified was exposure to > or =1 lot of recalled PDS (14 of 22 vs. 0/6, P = 0.02); the more recalled lots received, the higher the attack rate (P = 0.0001). Five of 47 PDS bags had detectable endotoxin; recalled lots were more likely to have measurable endotoxin than nonrecalled lots (5/19 vs. 0/17, P = 0.05). When case-patients resumed CCPD using PDS from non-recalled lots, no further cases were reported. CONCLUSIONS Our results suggest that this outbreak was caused by intrinsic PDS contamination with endotoxin. Pre-sterilization colony counts may be an important quality control indicator for CCPD fluids in conjunction with endotoxin levels.
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Affiliation(s)
- A J Mangram
- Hospital Infections Program, Centers for Disease Control and Prevention, Atlanta, Georgia 30333, USA.
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Abstract
BACKGROUND Blood bank recommendations specify that Ringer's lactate solution (LR) should be avoided while transfusing blood. However, there are few studies either evaluating or quantifying increased coagulation during rapid infusion of LR and blood. DESIGN AND METHODS Whole blood (WB, n = 25) and packed red blood cells (PRBC, n = 26) were rapidly admixed with normal saline (NS), Lactate solution and LR with 1 g (LR-1), 2 g (LR-2), and 5 g (LR-5) CaCl2/L solutions for assessment of infusion time, filter weight, and clot formation. RESULTS No significant differences in infusion time or filter weight using WB or PRBC with NS or LR were seen. No significant difference in clot formation between NS and LR with WB or PRBC was found, but the presence of visible clot was increased in the LR-5 group (P = 0.013, WB, and P = 0.002, PRBC). CONCLUSION A comparison of LR and NS with rapid infusion rates of blood showed no significant difference between infusion time, filter weight and clot formation. Blood bank guidelines should be revised to allow the use of LR in the rapid transfusion of PRBC.
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Affiliation(s)
- M Lorenzo
- Department of Surgery, University of California, San Francisco/Fresno Valley Medical Center, USA
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Ahlfors CE, Alley PA, Prendergast JJ, Parks S, Cheung AT. Effect of Implanted Insulin Pumpson Fluorescein Transcapillary Escape Timein Type 1 Diabetes Mellitus. Endocr Pract 1998; 4:73-5. [PMID: 15251748 DOI: 10.4158/ep.4.2.73] [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] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
OBJECTIVE To determine whether significant increases in fluorescein transcapillary escape time (FTET) would occur after treatment of patients with type 1 diabetes with insulin delivered intraperitoneally by a surgically implanted pump. METHODS Nine patients with type 1 diabetes who were otherwise healthy and had received surgically implanted insulin pumps on a study protocol were recruited to have three measurements of FTET and glycosylated hemoglobin during an 18-month period. Serum fluorescein-albumin binding was measured at the time of the final test. Control FTETs were measured in 46 patients with type 1 diabetes who did not have insulin pumps and in 15 adults without diabetes. RESULTS In the implanted insulin pump group, 50% of the FTETs were below normal, but no significant longitudinal change in FTETs was noted in eight of the nine study patients. The mean FTETs in the implanted insulin pump group were significantly higher than those of the control patients with diabetes but without insulin pumps (mean, 88 versus 62 seconds; P<0.05) but significantly lower than those of the control subjects without diabetes (88 versus 163 seconds; P<0.001). Four of the nine patients with implanted insulin pumps had normal FTETs on all three studies. This subgroup had used insulin pumps (external + implanted) for significantly longer periods (6.2 versus 2.6 years; P<0.05) than the other five patients. These differences within the implanted pump group did not correlate with differences in glycosylated hemoglobin values or fluorescein-albumin binding; however, the glycosylated hemoglobin levels before insulin pump implantation were significantly lower than those of the other five patients. Three patients with onset of type 1 diabetes before age 10 years had the lowest FTETs. CONCLUSION Implanted insulin pumps did not alter FTETs between 6 months and 32 months after pump implantation. Total time on insulin pumps (external and implanted) is associated with normal FTET, and onset of diabetes before age 10 years is associated with abnormal FTET.
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Affiliation(s)
- C E Ahlfors
- Department of Pediatrics, California Pacific Medical Center, San Francisco, California 94118, USA
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Parks S, Keating D, Evans AL, Williamson TH, Jay JL, Elliott AT. Comparison of repeatability of the multifocal electroretinogram and Humphrey perimeter. Doc Ophthalmol 1998; 92:281-9. [PMID: 9476595 DOI: 10.1007/bf02584082] [Citation(s) in RCA: 14] [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: 02/06/2023]
Abstract
Functional mapping of the retina by multifocal electroretinographic recordings is now possible. We compared the normal range, repeatability and response topography of this new technique with conventional static Humphrey perimetry to assess its suitability in clinical practice. The multifocal technique was performed on 60 age-matched controls. Measures of repeatability and reproducibility were obtained. Results were then compared with those obtained from a customized perimetry test. In both tests the coefficients of repeatability were found to decrease with eccentricity. The inherent measurement variation between techniques was comparable. Overall system variation indicates that the technique could be a useful tool at the clinical level.
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Affiliation(s)
- S Parks
- Tennent Institute of Ophthalmology, West Glasgow University NHS Trust, Scotland
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Abstract
The effect of filter bandwith on the multifocal electroretinogram was assessed by means of theoretical calculation, electronic simulation and real multifocal electroretinogram recordings. Waveform distortion by high-pass filtering on simulated square waves, normal electroretinogram waveforms and negative electroretinogram waveforms was demonstrated. The theory of the effect of differentiation on electroretinogram waveform shape by electronic filtering indicates that little effect would be observed by changing the input filter cut-off for normal electroretinographic waveform shapes. However, negative electroretinogram waveforms are differentiated when the high-pass filter setting is increased. The differentiation effect artificially recreates a positive component that could be mistaken as a b-wave component. To eliminate this effect when recording multifocal electroretinograms, a high-pass filter setting of less than 1 Hz should be used to preserve the true electroretinographic waveform shape.
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Affiliation(s)
- D Keating
- Department of Clinical Physics and Bio-Engineering, Western Infirmary, Glasgow, Scotland.
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49
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Abstract
During Drosophila gastrulation, mesodermal precursors are brought into the interior of the embryo by formation of the ventral furrow. The first steps of ventral furrow formation involve a flattening of the apical surface of the presumptive mesodermal cells and a constriction of their apical diameters. In embryos mutant for folded gastrulation (fog), these cell shape changes occur but the timing and synchrony of the constrictions are abnormal. A similar phenotype is seen in a maternal effect mutant, concertina (cta). fog encodes a putative secreted protein whereas cta encodes an (alpha)-subunit of a heterotrimeric G protein. We have proposed that localized expression of the fog signaling protein induces apical constriction by interacting with a receptor whose downstream cellular effects are mediated by the cta G(alpha)protein. <P> In order to test this model, we have ectopically expressed fog at the blastoderm stage using an inducible promoter. In addition, we have examined the constitutive activation of cta protein by blocking GTP hydrolysis using both in vitro synthesized mutant alleles and cholera toxin treatment. Activation of the fog/cta pathway by any of these procedures results in ectopic cell shape changes in the gastrula. Uniform fog expression rescues the gastrulation defects of fog null embryos but not cta mutant embryos, arguing that cta functions downstream of fog expression. The normal location of the ventral furrow in embryos with uniformly expressed fog suggests the existence of a fog-independent pathway determining mesoderm-specific cell behaviors and invagination. Epistasis experiments indicate that this pathway requires snail but not twist expression.
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Affiliation(s)
- P Morize
- Department of Molecular Biology, Howard Hughes Medical Institute, Princeton University, Princeton, NJ 08540, USA
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50
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Abstract
The purpose of this study was to elucidate the etiological pathways towards substance use and risky sexual behavior in female adolescent substance abusers. The study had three aims: (1) to determine the relations between behavioral dysregulation, negative affectivity, and childhood victimization with substance use and risky sexual behavior, (2) to determine whether these relations are mediated by internalizing symptomatology, antisocial behavior, and affiliating with an adult boyfriend; and (3) to determine whether age of menarche moderates the relation between the mediating variables and substance use and risky sexual behavior. Multiple behavioral, psychiatric interview, and self-report measures were used to index behavioral dysregulation, negative affectivity, childhood victimization, internalizing symptomatology, antisocial behavior, affiliation with adult boyfriends, substance use, and risky sexual behavior in 125 substance abusing female adolescents and 78 controls between the ages of 14-18 years. Structural equation modeling was used to determine the etiological pathways. Results indicated that behavioral dysregulation, negative affectivity, and childhood victimization were related to substance use and risky sexual behavior. Age of menarche was significantly correlated with affiliation with an older boyfriend and risky sexual behavior. Antisocial behavior mediated the associations between behavioral dysregulation, negative affectivity and childhood victimization with substance use and risky sexual behavior. Affiliation with an adult boyfriend was directly associated with substance use involvement and accounted for the relationship between chronological age and risky sexual behavior. Finally, late menarche enhanced the association between internalizing symptomatology and substance use involvement. The results highlight the importance of behavioral dysregulation, negative affectivity, and childhood victimization in predicting substance use and risky sexual behavior, as well as the finding that antisocial behavior and affiliation with an adult boyfriend may be etiologically important in predicting these outcomes. Therefore, from a prevention and treatment standpoint, behavioral and affective dysregulation, childhood victimization as well as antisocial behavior may serve as clinical 'gateways' for altering the developmental trajectory toward substance use and risky sexual behavior in high risk and substance abusing youth. For example, reducing dysregulation through behavior modification procedures that have been developed for conduct disordered children would appear to be a heuristic avenue of investigation emanating from the results obtained in this study.
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Affiliation(s)
- A Castillo Mezzich
- Department of Psychiatry, University of Pittsburgh Medical Center, Western Psychiatric Institute and Clinic, PA 15213, USA
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