1
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Buddeberg BS, Seeberger E, Bläsi C, Dutilh G, Steiner LA, Bandschapp O, Palanisamy A, Girard T. Is crystalloid co-loading necessary to prevent spinal hypotension during elective cesarean delivery? A randomized double-blind trial. Int J Obstet Anesth 2024; 58:103968. [PMID: 38485584 DOI: 10.1016/j.ijoa.2023.103968] [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] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/23/2023] [Revised: 11/23/2023] [Accepted: 11/30/2023] [Indexed: 05/07/2024]
Abstract
BACKGROUND Hypotension is common during spinal anesthesia for cesarean delivery. Preventive strategies include fluid loading and phenylephrine. We hypothesized that if prophylactic phenylephrine infusion is used, omission of fluid loading would be non-inferior to fluid co-loading in maintaining cardiac output. We assumed that if there was a difference, the increase in cardiac output would be greater in the no-loading than in the co-loading group. METHODS Term pregnant women scheduled for elective cesarean delivery were randomized to receive 1 L crystalloid co-loading or maintenance fluids only. Phenylephrine was titrated to maintain blood pressure. Changes in cardiac output following spinal anesthesia were the primary outcome. The study was powered as a non-inferiority trial, allowing the no-loading arm to have a 50% greater change in cardiac output. Heart rate, dose of phenylephrine, occurrence of nausea and vomiting, Apgar scores and neonatal acid base status were secondary outcomes. RESULTS Data from 63 women were analyzed. In contrast to our hypothesis, there was 33% less increase in cardiac output with no loading (ratio 0.67, 95% CI 0.15 to 1.36), and 60% greater reduction of cardiac output with no loading (ratio 1.6, 95% CI 1.0 to 2.7). Total dose of phenylephrine was higher in the no-loading group. There may be a less favorable neonatal acid base status without volume loading. CONCLUSION Omission of crystalloid co-loading leads to a decrease in cardiac output which has a potentially unfavorable impact on neonatal acid base status. We conclude that crystalloid co-loading may be useful in the presence of phenylephrine infusion.
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Affiliation(s)
- B S Buddeberg
- Clinic for Anaesthesia, Intermediate Care, Prehospital Emergency Medicine and Pain Therapy, University Hospital Basel, Switzerland; Department of Clinical Research, University of Basel, Switzerland.
| | - E Seeberger
- Clinic for Anaesthesia, Intermediate Care, Prehospital Emergency Medicine and Pain Therapy, University Hospital Basel, Switzerland
| | - C Bläsi
- Clinic for Anaesthesia, Intermediate Care, Prehospital Emergency Medicine and Pain Therapy, University Hospital Basel, Switzerland
| | - G Dutilh
- Department of Clinical Research, University of Basel, Switzerland
| | - L A Steiner
- Clinic for Anaesthesia, Intermediate Care, Prehospital Emergency Medicine and Pain Therapy, University Hospital Basel, Switzerland; Department of Clinical Research, University of Basel, Switzerland
| | - O Bandschapp
- Clinic for Anaesthesia, Intermediate Care, Prehospital Emergency Medicine and Pain Therapy, University Hospital Basel, Switzerland; Department of Clinical Research, University of Basel, Switzerland
| | - A Palanisamy
- Department of Anesthesiology, Washington University School of Medicine, St. Louis, MO, USA
| | - T Girard
- Clinic for Anaesthesia, Intermediate Care, Prehospital Emergency Medicine and Pain Therapy, University Hospital Basel, Switzerland; Department of Clinical Research, University of Basel, Switzerland
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2
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McGrath KE, Koniski AD, Murphy K, Getman M, An HH, Schulz VP, Kim AR, Zhang B, Schofield TL, Papoin J, Blanc L, Kingsley PD, Westhoff CM, Gallagher PG, Chou ST, Steiner LA, Palis J. BMI1 regulates human erythroid self-renewal through both gene repression and gene activation. bioRxiv 2024:2024.02.02.578704. [PMID: 38370741 PMCID: PMC10871261 DOI: 10.1101/2024.02.02.578704] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/20/2024]
Abstract
The limited proliferative capacity of erythroid precursors is a major obstacle to generate sufficient numbers of in vitro-derived red blood cells (RBC) for clinical purposes. We and others have determined that BMI1, a member of the polycomb repressive complex 1 (PRC1), is both necessary and sufficient to drive extensive proliferation of self-renewing erythroblasts (SREs). However, the mechanisms of BMI1 action remain poorly understood. BMI1 overexpression led to 10 billion-fold increase BMI1-induced (i)SRE self-renewal. Despite prolonged culture and BMI1 overexpression, human iSREs can terminally mature and agglutinate with typing reagent monoclonal antibodies against conventional RBC antigens. BMI1 and RING1B occupancy, along with repressive histone marks, were identified at known BMI1 target genes, including the INK-ARF locus, consistent with an altered cell cycle following BMI1 inhibition. We also identified upregulated BMI1 target genes with low repressive histone modifications, including key regulator of cholesterol homeostasis. Functional studies suggest that both cholesterol import and synthesis are essential for BMI1-associated self-renewal. These findings support the hypothesis that BMI1 regulates erythroid self-renewal not only through gene repression but also through gene activation and offer a strategy to expand the pool of immature erythroid precursors for eventual clinical uses.
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Affiliation(s)
- Kathleen E. McGrath
- Department of Pediatrics, University of Rochester Medical Center, Rochester, NY USA
| | - Anne D. Koniski
- Department of Pediatrics, University of Rochester Medical Center, Rochester, NY USA
| | - Kristin Murphy
- Department of Pediatrics, University of Rochester Medical Center, Rochester, NY USA
| | - Michael Getman
- Department of Pediatrics, University of Rochester Medical Center, Rochester, NY USA
| | - Hyun Hyung An
- Dept. of Pediatrics, The Children’s Hospital of Philadelphia, Philadelphia, PA, USA
| | | | - Ah Ram Kim
- Department of Pediatrics, University of Rochester Medical Center, Rochester, NY USA
| | - Bin Zhang
- Department of Pathology and Laboratory Medicine, University of Rochester Medical Center, Rochester, NY, USA
| | - Taylor L. Schofield
- Department of Pediatrics, University of Rochester Medical Center, Rochester, NY USA
| | - Julien Papoin
- Institute of Molecular Medicine, Feinstein Institutes for Medical Research, Manhasset, NY, USA
| | - Lionel Blanc
- Institute of Molecular Medicine, Feinstein Institutes for Medical Research, Manhasset, NY, USA
| | - Paul D. Kingsley
- Department of Pediatrics, University of Rochester Medical Center, Rochester, NY USA
| | | | - Patrick G. Gallagher
- Dept. of Pediatrics, Yale School of Medicine, New Haven, CT, USA
- Nationwide Children’s Hospital, Ohio State University, Columbus, OH, USA
| | - Stella T. Chou
- Dept. of Pediatrics, The Children’s Hospital of Philadelphia, Philadelphia, PA, USA
| | - Laurie A. Steiner
- Department of Pediatrics, University of Rochester Medical Center, Rochester, NY USA
| | - James Palis
- Department of Pediatrics, University of Rochester Medical Center, Rochester, NY USA
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3
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Papoin J, Yan H, Leduc M, Gall ML, Narla A, Palis J, Steiner LA, Gallagher PG, Hillyer CD, Gautier EF, Mohandas N, Blanc L. Phenotypic and proteomic characterization of the human erythroid progenitor continuum reveal dynamic changes in cell cycle and in metabolic pathways. Am J Hematol 2024; 99:99-112. [PMID: 37929634 PMCID: PMC10877306 DOI: 10.1002/ajh.27145] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2023] [Revised: 10/03/2023] [Accepted: 10/13/2023] [Indexed: 11/07/2023]
Abstract
Human erythropoiesis is a complex process leading to the production of 2.5 million red blood cells per second. Following commitment of hematopoietic stem cells to the erythroid lineage, this process can be divided into three distinct stages: erythroid progenitor differentiation, terminal erythropoiesis, and reticulocyte maturation. We recently resolved the heterogeneity of erythroid progenitors into four different subpopulations termed EP1-EP4. Here, we characterized the growth factor(s) responsiveness of these four progenitor populations in terms of proliferation and differentiation. Using mass spectrometry-based proteomics on sorted erythroid progenitors, we quantified the absolute expression of ~5500 proteins from EP1 to EP4. Further functional analyses highlighted dynamic changes in cell cycle in these populations with an acceleration of the cell cycle during erythroid progenitor differentiation. The finding that E2F4 expression was increased from EP1 to EP4 is consistent with the noted changes in cell cycle. Finally, our proteomic data suggest that the protein machinery necessary for both oxidative phosphorylation and glycolysis is present in these progenitor cells. Together, our data provide comprehensive insights into growth factor-dependence of erythroid progenitor proliferation and the proteome of four distinct populations of human erythroid progenitors which will be a useful framework for the study of erythroid disorders.
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Affiliation(s)
- Julien Papoin
- Institute of Molecular Medicine, Feinstein Institutes for
Medical Research, Manhasset, NY 11030 USA
- Université Jules Verne
| | - Hongxia Yan
- Red Cell Physiology Laboratory, Lindsey F. Kimball
Research Institute, New York Blood Center, New York, NY 10065 USA
| | - Marjorie Leduc
- Proteom’IC facility, Université Paris
Cité, CNRS, INSERM, Institut Cochin, F-75014 Paris, France
| | - Morgane Le Gall
- Proteom’IC facility, Université Paris
Cité, CNRS, INSERM, Institut Cochin, F-75014 Paris, France
| | - Anupama Narla
- Division of Hematology-Oncology, Department of Pediatrics,
Stanford University School of Medicine, Palo Alto, CA 94305 USA
| | - James Palis
- Center for Child Health Research, University of Rochester,
Rochester, NY 14642 USA
| | - Laurie A. Steiner
- Center for Child Health Research, University of Rochester,
Rochester, NY 14642 USA
| | - Patrick G. Gallagher
- Department of Pediatrics, Yale University, New Haven, CT
06520 USA
- Nationwide Children’s Hospital, Ohio State
University, Columbus, OH 43205 USA
| | - Christopher D. Hillyer
- Red Cell Physiology Laboratory, Lindsey F. Kimball
Research Institute, New York Blood Center, New York, NY 10065 USA
| | - Emilie-Fleur Gautier
- Proteom’IC facility, Université Paris
Cité, CNRS, INSERM, Institut Cochin, F-75014 Paris, France
| | - Narla Mohandas
- Red Cell Physiology Laboratory, Lindsey F. Kimball
Research Institute, New York Blood Center, New York, NY 10065 USA
| | - Lionel Blanc
- Institute of Molecular Medicine, Feinstein Institutes for
Medical Research, Manhasset, NY 11030 USA
- Division of Pediatrics Hematology/Oncology, Cohen
Children’s Medical Center, New Hyde Park NY 11040 USA
- Department of Molecular Medicine and Pediatrics, Zucker
School of Medicine at Hofstra/Northwell, Hempstead NY 11549 USA
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4
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Lv X, Murphy K, Murphy Z, Getman M, Rahman N, Nakamura Y, Blanc L, Gallagher PG, Palis J, Mohandas N, Steiner LA. HEXIM1 is an essential transcription regulator during human erythropoiesis. Blood 2023; 142:2198-2215. [PMID: 37738561 PMCID: PMC10733840 DOI: 10.1182/blood.2022019495] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2022] [Revised: 08/17/2023] [Accepted: 08/19/2023] [Indexed: 09/24/2023] Open
Abstract
ABSTRACT Regulation of RNA polymerase II (RNAPII) activity is an essential process that governs gene expression; however, its contribution to the fundamental process of erythropoiesis remains unclear. hexamethylene bis-acetamide inducible 1 (HEXIM1) regulates RNAPII activity by controlling the location and activity of positive transcription factor β. We identified a key role for HEXIM1 in controlling erythroid gene expression and function, with overexpression of HEXIM1 promoting erythroid proliferation and fetal globin expression. HEXIM1 regulated erythroid proliferation by enforcing RNAPII pausing at cell cycle check point genes and increasing RNAPII occupancy at genes that promote cycle progression. Genome-wide profiling of HEXIM1 revealed that it was increased at both repressed and activated genes. Surprisingly, there were also genome-wide changes in the distribution of GATA-binding factor 1 (GATA1) and RNAPII. The most dramatic changes occurred at the β-globin loci, where there was loss of RNAPII and GATA1 at β-globin and gain of these factors at γ-globin. This resulted in increased expression of fetal globin, and BGLT3, a long noncoding RNA in the β-globin locus that regulates fetal globin expression. GATA1 was a key determinant of the ability of HEXIM1 to repress or activate gene expression. Genes that gained both HEXIM1 and GATA1 had increased RNAPII and increased gene expression, whereas genes that gained HEXIM1 but lost GATA1 had an increase in RNAPII pausing and decreased expression. Together, our findings reveal a central role for universal transcription machinery in regulating key aspects of erythropoiesis, including cell cycle progression and fetal gene expression, which could be exploited for therapeutic benefit.
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Affiliation(s)
- Xiurui Lv
- Center for Child Health Research, University of Rochester, Rochester, NY
| | - Kristin Murphy
- Center for Child Health Research, University of Rochester, Rochester, NY
| | - Zachary Murphy
- Center for Child Health Research, University of Rochester, Rochester, NY
| | - Michael Getman
- Center for Child Health Research, University of Rochester, Rochester, NY
| | - Nabil Rahman
- Center for Child Health Research, University of Rochester, Rochester, NY
| | - Yukio Nakamura
- Rikagaku Kenkyūjyo (RIKEN) BioResource Research Center, Tsukuba Campus, Ibaraki, Japan
| | - Lionel Blanc
- Institute of Molecular Medicine, Feinstein Institutes for Medical Research, Manhasset, NY
| | | | - James Palis
- Center for Child Health Research, University of Rochester, Rochester, NY
| | - Narla Mohandas
- Red Cell Physiology Laboratory, Lindsey F. Kimball Research Institute, New York Blood Center, New York, NY
| | - Laurie A. Steiner
- Center for Child Health Research, University of Rochester, Rochester, NY
- Center for RNA Biology, University of Rochester, Rochester, NY
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5
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Alkhunaizi E, Martin N, Jelin AC, Rosner M, Bailey DJ, Steiner LA, Lakhani S, Ji W, Katzman PJ, Forster KR, Jarinova O, Shannon P, Chitayat D. Fetal akinesia deformation sequence syndrome associated with recessive TTN variants. Am J Med Genet A 2023; 191:760-769. [PMID: 36495114 PMCID: PMC9928776 DOI: 10.1002/ajmg.a.63071] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2022] [Revised: 10/12/2022] [Accepted: 11/12/2022] [Indexed: 12/14/2022]
Abstract
Arthrogryposis multiplex congenita (AMC) [also known as multiple joints contracture or Fetal Akinesia Deformation Sequence (FADS)] is etiologically a heterogeneous condition with an estimated incidence of approximately 1 in 3000 live births and much higher incidence when prenatally diagnosed cases are included. The condition can be acquired or secondary to fetal exposures and can also be caused by a variety of single-gene disorders affecting the brain, spinal cord, peripheral nerves, neuromuscular junction, muscle, and a variety of disorders affecting the connective tissues (Niles et al., Prenatal Diagnosis, 2019; 39:720-731). The introduction of next-generation gene sequencing uncovered many genes and causative variants of AMC but also identified genes that cause both dominant and recessive inherited conditions with the variability of clinical manifestations depending on the genes and variants. Molecular diagnosis in these cases is not only important for prognostication but also for the determination of recurrence risk and for providing reproductive options including preimplantation and prenatal diagnosis. TTN, the largest known gene in the human genome, has been known to be associated with autosomal dominant dilated cardiomyopathy. However, homozygote and compound heterozygote pathogenic variants with recessive inheritance have rarely been reported. We report the effect of recessive variants located within the fetal IC and/or N2BA isoforms in association with severe FADS in three families. All parents were healthy obligate carriers and none of them had cardiac or skeletal muscle abnormalities. This report solidifies FADS as an alternative phenotypic presentation associated with homozygote/compound heterozygous pathogenic variants in the TTN.
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Affiliation(s)
- Ebba Alkhunaizi
- Division of Clinical and Metabolic Genetics, Department of Pediatrics, The Hospital for Sick Children, University of Toronto, Toronto, Ontario, Canada
- The Prenatal Diagnosis and Medical Genetics Program, Department of Obstetrics and Gynecology, Mount Sinai Hospital, University of Toronto, Toronto, Ontario, Canada
| | - Nicole Martin
- Division of Clinical and Metabolic Genetics, Department of Pediatrics, The Hospital for Sick Children, University of Toronto, Toronto, Ontario, Canada
- The Prenatal Diagnosis and Medical Genetics Program, Department of Obstetrics and Gynecology, Mount Sinai Hospital, University of Toronto, Toronto, Ontario, Canada
| | - Angie C. Jelin
- Department of Gynecology and Obstetrics and Department of Genetic Medicine, Johns Hopkins Hospital, Baltimore, Maryland, USA
| | - Mara Rosner
- Department of Gynecology and Obstetrics, Center for Fetal Therapy, Johns Hopkins Hospital, Baltimore, Maryland, USA
| | - Diana J. Bailey
- Department of Pediatrics, University of Rochester, Rochester, New York, USA
| | - Laurie A. Steiner
- Department of Pediatrics, University of Rochester, Rochester, New York, USA
| | - Saquib Lakhani
- Department of Pediatrics, Pediatric Genomics Discovery Program, Yale University School of Medicine, New Haven, Connecticut, USA
| | - Weizhen Ji
- Department of Pediatrics, Pediatric Genomics Discovery Program, Yale University School of Medicine, New Haven, Connecticut, USA
| | - Philip J. Katzman
- Department of Pathology and Laboratory Medicine, University of Rochester Medical Center, Rochester, New York, USA
| | - Katherine R. Forster
- Department of Gynecology and Obstetrics, Center for Fetal Therapy, Johns Hopkins Hospital, Baltimore, Maryland, USA
- Division of Maternal Fetal Medicine, Sibley Memorial Hospital, Johns Hopkins Medicine, Washington, Washington, USA
| | - Olga Jarinova
- Department of Pathology and Laboratory Medicine, CHEO Genetics Diagnostic Laboratory, University of Ottawa, Ottawa, Ontario, Canada
| | - Patrick Shannon
- Department of Pathology and Laboratory Medicine, Mount Sinai Hospital, University of Toronto, Toronto, Ontario, Canada
| | - David Chitayat
- Division of Clinical and Metabolic Genetics, Department of Pediatrics, The Hospital for Sick Children, University of Toronto, Toronto, Ontario, Canada
- The Prenatal Diagnosis and Medical Genetics Program, Department of Obstetrics and Gynecology, Mount Sinai Hospital, University of Toronto, Toronto, Ontario, Canada
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6
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Papachristou A, Puelacher C, Glarner N, Strebel I, Steiger J, Diebold M, Lurati Buse G, Bolliger D, Steiner LA, Gurke L, Wolff T, Mujagic E, Gualandro DM, Mueller C, Breidthardt T. Renal failure: a non-cardiac source of high sensitivity cardiac troponin T. Eur Heart J 2022. [DOI: 10.1093/eurheartj/ehac544.2611] [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: 11/14/2022] Open
Abstract
Abstract
Background
Circulating high sensitivity cardiac troponin T (hs-cTnT) levels are frequently elevated in patients with end-stage renal disease (ESRD). The underlying pathophysiology is largely unknown. Currently, accumulation of hs-cTnT due to impaired renal clearance, as well as increased production caused by chronic cardiomyocyte injury is being discussed.
Purpose
The aim of this study was to assess the relative contribution of impaired renal clearance as a non-cardiac source of elevated hs-cTnT concentrations, using renal transplantation as an in vivo model of rapidly improved renal function and on a short-term basis rather unchanged cardiac pathology.
Methods
This single-centre study was a secondary analysis within a prospective active surveillance study program for perioperative myocardial infarction/injury (PMI). 42 consecutive high-risk patients undergoing renal transplantation without evidence of PMI were included. Serial creatinine and hs-cTnT (Elecsys, Roche) measurements were performed pre-transplant (baseline) and post-transplant on day (d) 1, between d2 and d5, and between d14 and d180. The effect of time and creatinine on hs-cTnT was estimated with a log-level non-linear mixed-effects model, where time and creatinine were treated as the fixed effects and subject as the random effect. Natural cubic splines were used to account for nonlinearity in the fixed effects.
Results
Baseline median serum creatinine concentration was 616 umol/L [interquartile range (IQR) 477–825], and significantly fell to 425 umol/L (IQR 313–619) on d1, 285 umol/L (IQR 194–509) on day2–5, and 116 umol/L (IQR 100–166) on d14–180 (p<0.001, p<0.001, and p=0.043, respectively; Figure 1A).
Pre-transplant hs-cTnT concentrations were above the 99th percentile (14ng/L) in all patients, median hs-cTnT concentration was 50 ng/L (IQR 35–70). In parallel to the fall in serum creatinine from baseline to d1, hs-cTnT concentrations significantly fell to 28 ng/L (IQR 15–40) on d1 (p<0.001), and then remained constant on d2–5 (27 ng/L (IQR 18–35)), and on d14–180 (24 ng/L (IQR 19–28); Figure 1B).
The mixed-effect model showed a significant decrease of hs-cTnT between baseline and d1 (p<0.001), whereas no significant change between d1 and d2 (p=0.82) occurred (Figure 2).
Conclusion
In contrast to the continuously falling serum creatinine levels, hs-cTnT concentrations reduced by about 50% only within the first 24 hours with a functional graft and then remained elevated above the 99th percentile. This suggests, that ESRD is a non-cardiac source of elevated circulating hs-cTnT concentrations, which contributes about 50%, while the other 50% seem related to chronic cardiomyocyte injury. Further studies assessing the long-term effect of renal transplantation on hs-cTnT levels and cardiac function are needed.
Funding Acknowledgement
Type of funding sources: Public Institution(s). Main funding source(s): Swiss National Science FoundationSwiss Heart Foundation
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Affiliation(s)
- A Papachristou
- University Hospital Basel, Cradiovascular Research Institute Basel and Department of Cardiology, Division of Internal Medicine , Basel , Switzerland
| | - C Puelacher
- University Hospital Basel, Cardiovascular Reasearch Institute Basel and Department of Cardiology , Basel , Switzerland
| | - N Glarner
- University Hospital Basel, Cardiovascular Reasearch Institute Basel and Department of Cardiology , Basel , Switzerland
| | - I Strebel
- University Hospital Basel, Cardiovascular Reasearch Institute Basel and Department of Cardiology , Basel , Switzerland
| | - J Steiger
- University Hospital Basel, Clinic for Transplantation Immunology and Nephrology , Basel , Switzerland
| | - M Diebold
- University Hospital Basel, Clinic for Transplantation Immunology and Nephrology , Basel , Switzerland
| | - G Lurati Buse
- University Hospital Duesseldorf, Department of Anaesthesiology , Duesseldorf , Germany
| | - D Bolliger
- University Hospital Basel, Clinic for Anaesthesia, Intermediate Care, Prehospital Emergency Medicine, and Pain Therapy , Basel , Switzerland
| | - L A Steiner
- University Hospital Basel, Clinic for Anaesthesia, Intermediate Care, Prehospital Emergency Medicine, and Pain Therapy , Basel , Switzerland
| | - L Gurke
- University Hospital Basel, Department of Vascular Surgery and Renal Transplantation , Basel , Switzerland
| | - T Wolff
- University Hospital Basel, Department of Vascular Surgery and Renal Transplantation , Basel , Switzerland
| | - E Mujagic
- University Hospital Basel, Department of Vascular Surgery and Renal Transplantation , Basel , Switzerland
| | - D M Gualandro
- University Hospital Basel, Cardiovascular Reasearch Institute Basel and Department of Cardiology , Basel , Switzerland
| | - C Mueller
- University Hospital Basel, Cardiovascular Reasearch Institute Basel and Department of Cardiology , Basel , Switzerland
| | - T Breidthardt
- University Hospital Basel, Cradiovascular Research Institute Basel and Department of Cardiology, Division of Internal Medicine , Basel , Switzerland
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7
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Guo B, Friedland SC, Alexander W, Myers JA, Wang W, O'Dell MR, Getman M, Whitney-Miller CL, Agostini-Vulaj D, Huber AR, Mello SS, Vertino PM, Land HK, Steiner LA, Hezel AF. Arid1a mutation suppresses TGF-β signaling and induces cholangiocarcinoma. Cell Rep 2022; 40:111253. [PMID: 36044839 PMCID: PMC9808599 DOI: 10.1016/j.celrep.2022.111253] [Citation(s) in RCA: 13] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2022] [Revised: 06/02/2022] [Accepted: 08/01/2022] [Indexed: 01/07/2023] Open
Abstract
Activating KRAS mutations and functional loss of members of the SWI/SNF complex, including ARID1A, are found together in the primary liver tumor cholangiocarcinoma (CC). How these mutations cooperate to promote CC has not been established. Using murine models of hepatocyte and biliary-specific lineage tracing, we show that Kras and Arid1a mutations drive the formation of CC and tumor precursors from the biliary compartment, which are accelerated by liver inflammation. Using cultured cells, we find that Arid1a loss causes cellular proliferation, escape from cell-cycle control, senescence, and widespread changes in chromatin structure. Notably, we show that the biliary proliferative response elicited by Kras/Arid1a cooperation and tissue injury in CC is caused by failed engagement of the TGF-β-Smad4 tumor suppressor pathway. We thus identify an ARID1A-TGF-β-Smad4 axis as essential in limiting the biliary epithelial response to oncogenic insults, while its loss leads to biliary pre-neoplasia and CC.
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Affiliation(s)
- Bing Guo
- Department of Biomedical Genetics, University of Rochester Medical Center, Rochester, NY 14642, USA; Division of Hematology and Oncology, Department of Medicine, Wilmot Cancer Institute, University of Rochester Medical Center, 300 Elmwood Avenue, Rochester, NY 14642, USA
| | - Scott C Friedland
- Department of Biomedical Genetics, University of Rochester Medical Center, Rochester, NY 14642, USA
| | - William Alexander
- Department of Biomedical Genetics, University of Rochester Medical Center, Rochester, NY 14642, USA
| | - Jacquelyn A Myers
- Genomics Research Center, University of Rochester Medical Center, Rochester, NY 14642, USA
| | - Wenjia Wang
- Department of Biomedical Genetics, University of Rochester Medical Center, Rochester, NY 14642, USA; Division of Hematology and Oncology, Department of Medicine, Wilmot Cancer Institute, University of Rochester Medical Center, 300 Elmwood Avenue, Rochester, NY 14642, USA
| | - Michael R O'Dell
- Division of Hematology and Oncology, Department of Medicine, Wilmot Cancer Institute, University of Rochester Medical Center, 300 Elmwood Avenue, Rochester, NY 14642, USA
| | - Michael Getman
- Department of Pediatrics, University of Rochester Medical Center, Rochester, NY 14642, USA
| | - Christa L Whitney-Miller
- Department of Pathology and Laboratory Medicine, University of Rochester Medical Center, Rochester, NY 14642, USA
| | - Diana Agostini-Vulaj
- Department of Pathology and Laboratory Medicine, University of Rochester Medical Center, Rochester, NY 14642, USA
| | - Aaron R Huber
- Department of Pathology and Laboratory Medicine, University of Rochester Medical Center, Rochester, NY 14642, USA
| | - Stephano S Mello
- Department of Biomedical Genetics, University of Rochester Medical Center, Rochester, NY 14642, USA
| | - Paula M Vertino
- Department of Biomedical Genetics, University of Rochester Medical Center, Rochester, NY 14642, USA
| | - Hartmut K Land
- Department of Biomedical Genetics, University of Rochester Medical Center, Rochester, NY 14642, USA; Division of Hematology and Oncology, Department of Medicine, Wilmot Cancer Institute, University of Rochester Medical Center, 300 Elmwood Avenue, Rochester, NY 14642, USA
| | - Laurie A Steiner
- Department of Pediatrics, University of Rochester Medical Center, Rochester, NY 14642, USA
| | - Aram F Hezel
- Department of Biomedical Genetics, University of Rochester Medical Center, Rochester, NY 14642, USA; Division of Hematology and Oncology, Department of Medicine, Wilmot Cancer Institute, University of Rochester Medical Center, 300 Elmwood Avenue, Rochester, NY 14642, USA.
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8
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Dulmovits BM, Tang Y, Papoin J, He M, Li J, Yang H, Addorisio ME, Kennedy L, Khan M, Brindley E, Ashley RJ, Ackert-Bicknell C, Hale J, Kurita R, Nakamura Y, Diamond B, Barnes BJ, Hermine O, Gallagher PG, Steiner LA, Lipton JM, Taylor N, Mohandas N, Andersson U, Al-Abed Y, Tracey KJ, Blanc L. HMGB1-mediated restriction of EPO signaling contributes to anemia of inflammation. Blood 2022; 139:3181-3193. [PMID: 35040907 PMCID: PMC9136881 DOI: 10.1182/blood.2021012048] [Citation(s) in RCA: 21] [Impact Index Per Article: 10.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2021] [Accepted: 12/22/2021] [Indexed: 11/20/2022] Open
Abstract
Anemia of inflammation, also known as anemia of chronic disease, is refractory to erythropoietin (EPO) treatment, but the mechanisms underlying the EPO refractory state are unclear. Here, we demonstrate that high mobility group box-1 protein (HMGB1), a damage-associated molecular pattern molecule recently implicated in anemia development during sepsis, leads to reduced expansion and increased death of EPO-sensitive erythroid precursors in human models of erythropoiesis. HMGB1 significantly attenuates EPO-mediated phosphorylation of the Janus kinase 2/STAT5 and mTOR signaling pathways. Genetic ablation of receptor for advanced glycation end products, the only known HMGB1 receptor expressed by erythroid precursors, does not rescue the deleterious effects of HMGB1 on EPO signaling, either in human or murine precursors. Furthermore, surface plasmon resonance studies highlight the ability of HMGB1 to interfere with the binding between EPO and the EPOR. Administration of a monoclonal anti-HMGB1 antibody after sepsis onset in mice partially restores EPO signaling in vivo. Thus, HMGB1-mediated restriction of EPO signaling contributes to the chronic phase of anemia of inflammation.
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Affiliation(s)
- Brian M Dulmovits
- Zucker School of Medicine at Hofstra Northwell, Hempstead, NY
- Institute of Molecular Medicine, and
| | | | | | - Mingzhu He
- Institute of Bioelectronic Medicine, Feinstein Institutes for Medical Research, Manhasset, NY
| | - Jianhua Li
- Institute of Bioelectronic Medicine, Feinstein Institutes for Medical Research, Manhasset, NY
| | - Huan Yang
- Institute of Bioelectronic Medicine, Feinstein Institutes for Medical Research, Manhasset, NY
| | - Meghan E Addorisio
- Institute of Bioelectronic Medicine, Feinstein Institutes for Medical Research, Manhasset, NY
| | | | | | - Elena Brindley
- Zucker School of Medicine at Hofstra Northwell, Hempstead, NY
- Institute of Molecular Medicine, and
| | - Ryan J Ashley
- Zucker School of Medicine at Hofstra Northwell, Hempstead, NY
- Institute of Molecular Medicine, and
| | | | - John Hale
- Red Cell Physiology Laboratory, New York Blood Center, New York, NY
| | - Ryo Kurita
- Central Blood Institute, Japanese Red Cross Society, Minato-ku, Tokyo, Japan
| | - Yukio Nakamura
- Cell Engineering Division, RIKEN BioResource Research Center, Tsukuba, Ibaraki, Japan
| | - Betty Diamond
- Zucker School of Medicine at Hofstra Northwell, Hempstead, NY
- Institute of Molecular Medicine, and
| | - Betsy J Barnes
- Zucker School of Medicine at Hofstra Northwell, Hempstead, NY
- Institute of Molecular Medicine, and
| | - Olivier Hermine
- INSERM Unité Mixte de Recherche (UMR) 1163, IMAGINE Institute, Paris, France
| | | | - Laurie A Steiner
- Department of Pediatrics, University of Rochester, Rochester, NY
| | - Jeffrey M Lipton
- Zucker School of Medicine at Hofstra Northwell, Hempstead, NY
- Institute of Molecular Medicine, and
- Pediatric Hematology/Oncology, Cohen Children's Medical Center, New Hyde Park, NY
| | - Naomi Taylor
- Pediatric Oncology Branch, National Cancer Institute, Center for Cancer Research, National Institutes of Health, Bethesda, MD; and
| | - Narla Mohandas
- Red Cell Physiology Laboratory, New York Blood Center, New York, NY
| | - Ulf Andersson
- Department of Women's and Children's Health, Karolinska Institute, Stockholm, Sweden
| | - Yousef Al-Abed
- Zucker School of Medicine at Hofstra Northwell, Hempstead, NY
- Institute of Bioelectronic Medicine, Feinstein Institutes for Medical Research, Manhasset, NY
| | - Kevin J Tracey
- Zucker School of Medicine at Hofstra Northwell, Hempstead, NY
- Institute of Bioelectronic Medicine, Feinstein Institutes for Medical Research, Manhasset, NY
| | - Lionel Blanc
- Zucker School of Medicine at Hofstra Northwell, Hempstead, NY
- Institute of Molecular Medicine, and
- INSERM Unité Mixte de Recherche (UMR) 1163, IMAGINE Institute, Paris, France
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9
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Murphy ZC, Murphy K, Myers J, Getman M, Couch T, Schulz VP, Lezon-Geyda K, Palumbo C, Yan H, Mohandas N, Gallagher PG, Steiner LA. Regulation of RNA polymerase II activity is essential for terminal erythroid maturation. Blood 2021; 138:1740-1756. [PMID: 34075391 PMCID: PMC8569412 DOI: 10.1182/blood.2020009903] [Citation(s) in RCA: 17] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2020] [Accepted: 04/30/2021] [Indexed: 11/20/2022] Open
Abstract
The terminal maturation of human erythroblasts requires significant changes in gene expression in the context of dramatic nuclear condensation. Defects in this process are associated with inherited anemias and myelodysplastic syndromes. The progressively dense appearance of the condensing nucleus in maturing erythroblasts led to the assumption that heterochromatin accumulation underlies this process, but despite extensive study, the precise mechanisms underlying this essential biologic process remain elusive. To delineate the epigenetic changes associated with the terminal maturation of human erythroblasts, we performed mass spectrometry of histone posttranslational modifications combined with chromatin immunoprecipitation coupled with high-throughput sequencing, Assay for Transposase Accessible Chromatin, and RNA sequencing. Our studies revealed that the terminal maturation of human erythroblasts is associated with a dramatic decline in histone marks associated with active transcription elongation, without accumulation of heterochromatin. Chromatin structure and gene expression were instead correlated with dynamic changes in occupancy of elongation competent RNA polymerase II, suggesting that terminal erythroid maturation is controlled largely at the level of transcription. We further demonstrate that RNA polymerase II "pausing" is highly correlated with transcriptional repression, with elongation competent RNA polymerase II becoming a scare resource in late-stage erythroblasts, allocated to erythroid-specific genes. Functional studies confirmed an essential role for maturation stage-specific regulation of RNA polymerase II activity during erythroid maturation and demonstrate a critical role for HEXIM1 in the regulation of gene expression and RNA polymerase II activity in maturing erythroblasts. Taken together, our findings reveal important insights into the mechanisms that regulate terminal erythroid maturation and provide a novel paradigm for understanding normal and perturbed erythropoiesis.
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Affiliation(s)
| | | | - Jacquelyn Myers
- Department of Pediatrics and
- Genomics Resource Center, University of Rochester, Rochester, NY
| | | | | | | | | | - Cal Palumbo
- Genomics Resource Center, University of Rochester, Rochester, NY
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10
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Murphy ZC, Getman MR, Myers JA, Burgos Villar KN, Leshen E, Kurita R, Nakamura Y, Steiner LA. Codanin-1 mutations engineered in human erythroid cells demonstrate role of CDAN1 in terminal erythroid maturation. Exp Hematol 2020; 91:32-38.e6. [PMID: 33075436 DOI: 10.1016/j.exphem.2020.09.201] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2020] [Revised: 09/14/2020] [Accepted: 09/15/2020] [Indexed: 11/29/2022]
Abstract
The generation of a functional erythrocyte from a committed progenitor requires significant changes in gene expression during hemoglobin accumulation, rapid cell division, and nuclear condensation. Congenital dyserythropoietic anemia type I (CDA-I) is an autosomal recessive disease that presents with erythroid hyperplasia in the bone marrow. Erythroblasts in patients with CDA-I are frequently binucleate and have chromatin bridging and defective chromatin condensation. CDA-1 is most commonly caused by mutations in Codanin-1 (CDAN1). The function of CDAN1 is poorly understood but it is thought to regulate histone incorporation into nascent DNA during cellular replication. The study of CDA-1 has been limited by the lack of in vitro models that recapitulate key features of the disease, and most studies on CDAN1 function have been done in nonerythroid cells. To model CDA-I we generated HUDEP2 mutant lines with deletion or mutation of R1042 of CDAN1, mirroring mutations found in CDA-1 patients. CDAN1 mutant cell lines had decreased viability and increased intercellular bridges and binucleate cells. Further, they had alterations in histone acetylation associated with prematurely elevated erythroid gene expression, including gamma globin. Together, these data imply a specific functional role for CDAN1, specifically R1042 on exon 24, in the regulation of DNA replication and organization during erythroid maturation. Most importantly, generation of models with specific patient mutations, such as R1042, will provide further mechanistic insights into CDA-I pathology.
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Affiliation(s)
- Zachary C Murphy
- Center for Pediatric Biomedical Research, Department of Pediatrics, University of Rochester, Rochester, NY
| | - Michael R Getman
- Center for Pediatric Biomedical Research, Department of Pediatrics, University of Rochester, Rochester, NY
| | - Jaquelyn A Myers
- Center for Pediatric Biomedical Research, Department of Pediatrics, University of Rochester, Rochester, NY
| | | | - Emily Leshen
- Center for Pediatric Biomedical Research, Department of Pediatrics, University of Rochester, Rochester, NY
| | - Ryo Kurita
- Research and Development Department, Central Blood Institute, Blood Service Headquarters, Japanese Red Cross Society, Tokyo, Japan
| | - Yukio Nakamura
- Cell Engineering Division, RIKEN BioResource Center, Tsukuba, Ibaraki, Japan
| | - Laurie A Steiner
- Center for Pediatric Biomedical Research, Department of Pediatrics, University of Rochester, Rochester, NY.
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11
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Myers JA, Couch T, Murphy Z, Malik J, Getman M, Steiner LA. The histone methyltransferase Setd8 alters the chromatin landscape and regulates the expression of key transcription factors during erythroid differentiation. Epigenetics Chromatin 2020; 13:16. [PMID: 32178723 PMCID: PMC7075014 DOI: 10.1186/s13072-020-00337-9] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2019] [Accepted: 03/02/2020] [Indexed: 12/23/2022] Open
Abstract
Background SETD8 is the sole methyltransferase capable of mono-methylating histone H4, lysine 20. SETD8 and H4K20me1 play a role in a number of essential biologic processes, including cell cycle progression, establishment of higher order chromatin structure, and transcriptional regulation. SETD8 is highly expressed in erythroid cells and erythroid deletion of Setd8 is embryonic lethal by embryonic day 11.5 (E11.5) due to profound anemia, suggesting that it has an erythroid-specific function. The function of SETD8 in the hemopoietic system is poorly understood. The goal of our study was to gain insights into the function of SETD8 during erythroid differentiation. Results We performed ATAC-seq (assay for transposase-accessible chromatin) on sorted populations of E10.5 Setd8 mutant and control erythroblasts. Accessibility profiles were integrated with expression changes and a mark of heterochromatin (H3K27me3) performed in wild-type E10.5 erythroblasts to further understand the role of SETD8 in erythropoiesis. Data integration identified regions of greater chromatin accessibility in Setd8 mutant cells that co-located with H3K27me3 in wild-type E10.5 erythroblasts suggesting that these regions, and their associated genes, are repressed during normal erythropoiesis. The majority of these more accessible regions were located in promoters and they frequently co-located with the NFY complex. Pathway analysis of genes identified through data integration revealed stemness-related pathways. Among those genes were multiple transcriptional regulators active in multipotent progenitors, but repressed during erythroid differentiation including Hhex, Hlx, and Gata2. Consistent with a role for SETD8 in erythroid specification, SETD8 expression is up-regulated upon erythroid commitment, and Setd8 disruption impairs erythroid colony forming ability. Conclusion Taken together, our results suggest that SETD8 is an important regulator of the chromatin landscape during erythroid differentiation, particularly at promoters. Our results also identify a novel role for Setd8 in the establishment of appropriate patterns of lineage-restricted gene expression during erythroid differentiation.
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Affiliation(s)
- Jacquelyn A Myers
- Center for Pediatric Biomedical Research, Department of Pediatrics, University of Rochester, Rochester, NY, USA.,Genomics Resource Center, University of Rochester, Rochester, NY, USA
| | - Tyler Couch
- Center for Pediatric Biomedical Research, Department of Pediatrics, University of Rochester, Rochester, NY, USA
| | - Zachary Murphy
- Center for Pediatric Biomedical Research, Department of Pediatrics, University of Rochester, Rochester, NY, USA
| | - Jeffrey Malik
- Center for Pediatric Biomedical Research, Department of Pediatrics, University of Rochester, Rochester, NY, USA.,Genomics Resource Center, University of Rochester, Rochester, NY, USA
| | - Michael Getman
- Center for Pediatric Biomedical Research, Department of Pediatrics, University of Rochester, Rochester, NY, USA
| | - Laurie A Steiner
- Center for Pediatric Biomedical Research, Department of Pediatrics, University of Rochester, Rochester, NY, USA.
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12
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Steiner LA, Getman M, Schiralli Lester GM, Iqbal MA, Katzman P, Szafranski P, Stankiewicz P, Bhattacharya S, Mariani T, Pryhuber G, Lin X, Young JL, Dean DA, Scheible K. Disruption of normal patterns of FOXF1 expression in a lethal disorder of lung development. J Med Genet 2019; 57:296-300. [PMID: 31662342 DOI: 10.1136/jmedgenet-2019-106095] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [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: 02/20/2019] [Revised: 09/06/2019] [Accepted: 09/13/2019] [Indexed: 01/22/2023]
Abstract
BACKGROUND Alveolar capillary dysplasia with misalignment of the pulmonary veins (ACDMPV) is a lethal disorder of lung development. ACDMPV is associated with haploinsufficiency of the transcription factor FOXF1, which plays an important role in the development of the lung and intestine. CNVs upstream of the FOXF1 gene have also been associated with an ACDMPV phenotype, but mechanism(s) by which these deletions disrupt lung development are not well understood. The objective of our study is to gain insights into the mechanisms by which CNVs contribute to an ACDMPV phenotype. METHODS We analysed primary lung tissue from an infant with classic clinical and histological findings of ACDMPV and harboured a 340 kb deletion on chromosome 16q24.1 located 250 kb upstream of FOXF1. RESULTS In RNA generated from paraffin-fixed lung sections, our patient had lower expression of FOXF1 than age-matched controls. He also had an abnormal pattern of FOXF1 protein expression, with a dramatic loss of FOXF1 expression in the lung. To gain insights into the mechanisms underlying these changes, we assessed the epigenetic landscape using chromatin immunoprecipitation, which demonstrated loss of histone H3 lysine 27 acetylation (H3K27Ac), an epigenetic mark of active enhancers, in the region of the deletion. CONCLUSIONS Together, these data suggest that the deletion disrupts an enhancer responsible for directing FOXF1 expression in the developing lung and provide novel insights into the mechanisms underlying a fatal developmental lung disorder.
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Affiliation(s)
| | - Michael Getman
- Pediatrics, University of Rochester, Rochester, New York, USA
| | | | - M Anwar Iqbal
- Pediatrics, University of Rochester, Rochester, New York, USA
| | - Philip Katzman
- Pathology, University of Rochester, Rochester, New York, USA
| | - Przemyslaw Szafranski
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, Texas, USA
| | - Pawel Stankiewicz
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, Texas, USA
| | | | - Thomas Mariani
- Division of Neonatology and Center for Pediatric Biomedical Research, University of Rochester, Rochester, New York, USA
| | - Gloria Pryhuber
- Pediatrics, University of Rochester, Rochester, New York, USA
| | - Xin Lin
- Pediatrics, University of Rochester, Rochester, New York, USA
| | | | - David A Dean
- Pediatrics, University of Rochester, Rochester, New York, USA
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13
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Wang W, Friedland SC, Guo B, O’Dell MR, Alexander WB, Whitney-Miller CL, Agostini-Vulaj D, Huber AR, Myers JR, Ashton JM, Dunne RF, Steiner LA, Hezel AF. ARID1A, a SWI/SNF subunit, is critical to acinar cell homeostasis and regeneration and is a barrier to transformation and epithelial-mesenchymal transition in the pancreas. Gut 2019; 68:1245-1258. [PMID: 30228219 PMCID: PMC6551318 DOI: 10.1136/gutjnl-2017-315541] [Citation(s) in RCA: 52] [Impact Index Per Article: 10.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/25/2017] [Revised: 08/07/2018] [Accepted: 08/09/2018] [Indexed: 12/12/2022]
Abstract
OBJECTIVE Here, we evaluate the contribution of AT-rich interaction domain-containing protein 1A (ARID1A), the most frequently mutated member of the SWItch/sucrose non-fermentable (SWI/SNF) complex, in pancreatic homeostasis and pancreatic ductal adenocarcinoma (PDAC) pathogenesis using mouse models. DESIGN Mice with a targeted deletion of Arid1a in the pancreas by itself and in the context of two common genetic alterations in PDAC, Kras and p53, were followed longitudinally. Pancreases were examined and analysed for proliferation, response to injury and tumourigenesis. Cancer cell lines derived from these models were analysed for clonogenic, migratory, invasive and transcriptomic changes. RESULTS Arid1a deletion in the pancreas results in progressive acinar-to-ductal metaplasia (ADM), loss of acinar mass, diminished acinar regeneration in response to injury and ductal cell expansion. Mutant Kras cooperates with homozygous deletion of Arid1a, leading to intraductal papillary mucinous neoplasm (IPMN). Arid1a loss in the context of mutant Kras and p53 leads to shorter tumour latency, with the resulting tumours being poorly differentiated. Cancer cell lines derived from Arid1a-mutant tumours are more mesenchymal, migratory, invasive and capable of anchorage-independent growth; gene expression analysis showed activation of epithelial-mesenchymal transition (EMT) and stem cell identity pathways that are partially dependent on Arid1a loss for dysregulation. CONCLUSIONS ARID1A plays a key role in pancreatic acinar homeostasis and response to injury. Furthermore, ARID1A restrains oncogenic KRAS-driven formation of premalignant proliferative IPMN. Arid1a-deficient PDACs are poorly differentiated and have mesenchymal features conferring migratory/invasive and stem-like properties.
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Affiliation(s)
- Wenjia Wang
- Department of Medicine, Hematology and Oncology Division, Wilmot Cancer Institute, University of Rochester Medical Center, Rochester, New York, USA
| | - Scott C Friedland
- Department of Biomedical Genetics, University of Rochester Medical Center, Rochester, New York, USA
| | - Bing Guo
- Department of Medicine, Hematology and Oncology Division, Wilmot Cancer Institute, University of Rochester Medical Center, Rochester, New York, USA
| | - Michael R O’Dell
- Department of Medicine, Hematology and Oncology Division, Wilmot Cancer Institute, University of Rochester Medical Center, Rochester, New York, USA
| | - William B Alexander
- Department of Biomedical Genetics, University of Rochester Medical Center, Rochester, New York, USA
| | - Christa L Whitney-Miller
- Department of Pathology and Laboratory Medicine, University of Rochester Medical Center, Rochester, New York, USA
| | - Diana Agostini-Vulaj
- Department of Pathology and Laboratory Medicine, University of Rochester Medical Center, Rochester, New York, USA
| | - Aaron R Huber
- Department of Pathology and Laboratory Medicine, University of Rochester Medical Center, Rochester, New York, USA
| | - Jason R Myers
- Genomics Research Center, University of Rochester Medical Center, Rochester, New York, USA
| | - John M Ashton
- Genomics Research Center, University of Rochester Medical Center, Rochester, New York, USA
| | - Richard F Dunne
- Department of Medicine, Hematology and Oncology Division, Wilmot Cancer Institute, University of Rochester Medical Center, Rochester, New York, USA
| | - Laurie A Steiner
- Department of Pediatrics, University of Rochester Medical Center, Rochester, New York, USA
| | - Aram F Hezel
- Department of Medicine, Hematology and Oncology Division, Wilmot Cancer Institute, University of Rochester Medical Center, Rochester, New York, USA,Department of Biomedical Genetics, University of Rochester Medical Center, Rochester, New York, USA
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14
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Couch T, Murphy Z, Getman M, Kurita R, Nakamura Y, Steiner LA. Human erythroblasts with c-Kit activating mutations have reduced cell culture costs and remain capable of terminal maturation. Exp Hematol 2019; 74:19-24.e4. [PMID: 31004744 DOI: 10.1016/j.exphem.2019.04.001] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2019] [Revised: 04/10/2019] [Accepted: 04/13/2019] [Indexed: 11/16/2022]
Abstract
A major barrier to the in vitro production of red blood cells for transfusion therapy is the cost of culture components, with cytokines making up greater than half of the culture costs. Cell culture cytokines also represent a major expense for in vitro studies of human erythropoiesis. HUDEP-2 cells are an E6/E7 immortalized erythroblast line used for the in vitro study of human erythropoiesis. In contrast to other cell lines used to study human erythropoiesis, such as K562 cells, HUDEP-2 cells are capable of terminal maturation, including hemoglobin accumulation and chromatin condensation. As such, HUDEP-2 cells represent a valuable resource for studies not amenable to primary cell cultures; however, reliance on the cytokines stem cell factor (SCF) and erythropoietin (EPO) make HUDEP-2 cultures very expensive to maintain. To decrease culture costs, we used CRISPR/Cas9 genome editing to introduce a constitutively activating mutation into the SCF receptor gene KIT, with the goal of generating human erythroblasts capable of SCF-independent expansion. Three independent HUDEP-2 lines with unique KIT receptor genotypes were generated and characterized. All three lines were capable of robust expansion in the absence of SCF, decreasing culture costs by approximately half. Importantly, these lines remained capable of terminal maturation. Together, these data suggest that introduction of c-Kit activating mutations into human erythroblasts may help reduce the cost of erythroblast culture, making the in vitro study of erythropoiesis, and the eventual in vitro production of red blood cells, more economically feasible.
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Affiliation(s)
- Tyler Couch
- Department of Biochemistry and Biophysics, University of Rochester, Rochester, NY; Center for Pediatric Biomedical Research, Department of Pediatrics, University of Rochester, Rochester, NY
| | - Zachary Murphy
- Center for Pediatric Biomedical Research, Department of Pediatrics, University of Rochester, Rochester, NY
| | - Michael Getman
- Center for Pediatric Biomedical Research, Department of Pediatrics, University of Rochester, Rochester, NY
| | - Ryo Kurita
- Cell Engineering Division, RIKEN BioResource Center, Tsukuba, Ibaraki, Japan
| | - Yukio Nakamura
- Cell Engineering Division, RIKEN BioResource Center, Tsukuba, Ibaraki, Japan
| | - Laurie A Steiner
- Center for Pediatric Biomedical Research, Department of Pediatrics, University of Rochester, Rochester, NY.
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15
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Dell-Kuster S, Hoesli I, Lapaire O, Seeberger E, Steiner LA, Bucher HC, Girard T. Efficacy and safety of carbetocin given as an intravenous bolus compared with short infusion for Caesarean section - double-blind, double-dummy, randomized controlled non-inferiority trial. Br J Anaesth 2018; 118:772-780. [PMID: 28498927 DOI: 10.1093/bja/aex034] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 01/21/2017] [Indexed: 11/13/2022] Open
Abstract
Background Carbetocin is a synthetic oxytocin-analogue, which should be administered as bolus according to manufacturer's recommendations. A higher speed of oxytocin administration leads to increased cardiovascular side-effects. It is unclear whether carbetocin administration as short infusion has the same efficacy on uterine tone compared with bolus administration and whether haemodynamic parameters differ. Methods In this randomized, double-blind, non-inferiority trial, women undergoing planned or unplanned Caesarean section (CS) under regional anaesthesia received a bolus and a short infusion, only one of which contained carbetocin 100 mcg (double dummy). Obstetricians quantified uterine tone two, three, five and 10 min after cord-clamping by manual palpation using a linear analogue scale from 0 to 100. We evaluated whether the lower limit of the 95% CI of the difference in maximum uterine tone within the first five min after cord-clamping did not include the pre-specified non-inferiority limit of -10. Results Between December 2014 and November 2015, 69 patients were randomized to receive carbetocin as bolus and 71 to receive it as short infusion. Maximal uterine tone was 89 in the bolus and 88 in the short infusion group (mean difference -1.3, 95% CI -5.7 to 3.1). Bp, calculated blood loss, use of additional uterotonics, and side-effects were comparable. Conclusions Administration of carbetocin as short infusion does not compromise uterine tone and has similar cardiovascular side-effects as a slow i.v. bolus. In accordance with current recommendations for oxytocin, carbetocin can safely be administered as short -infusion during planned or unplanned CS. Clinical trial registration ClinicalTrials.gov NCT02221531 and www.kofam.ch SNCTP000001197.
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Affiliation(s)
- S Dell-Kuster
- Department of Anaesthesiology, Surgical Intensive Care, Prehospital Emergency Medicine and Pain Therapy, Basel, Switzerland.,Basel Institute for Clinical Epidemiology and Biostatistics, Basel, Switzerland
| | - I Hoesli
- Basel Institute of Clinical Epidemiology and Biostatistics, University Basel, Basel, Switzerland.,Department of Clinical Research, University Basel, Basel, Switzerland
| | - O Lapaire
- Basel Institute of Clinical Epidemiology and Biostatistics, University Basel, Basel, Switzerland
| | - E Seeberger
- Department of Anaesthesiology, Surgical Intensive Care, Prehospital Emergency Medicine and Pain Therapy, Basel, Switzerland
| | - L A Steiner
- Department of Anaesthesiology, Surgical Intensive Care, Prehospital Emergency Medicine and Pain Therapy, Basel, Switzerland.,Department of Clinical Research, University Basel, Basel, Switzerland
| | - H C Bucher
- Basel Institute for Clinical Epidemiology and Biostatistics, Basel, Switzerland.,Department of Clinical Research, University Basel, Basel, Switzerland
| | - T Girard
- Department of Anaesthesiology, Surgical Intensive Care, Prehospital Emergency Medicine and Pain Therapy, Basel, Switzerland
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16
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Malik J, Lillis JA, Couch T, Getman M, Steiner LA. The Methyltransferase Setd8 Is Essential for Erythroblast Survival and Maturation. Cell Rep 2018; 21:2376-2383. [PMID: 29186677 DOI: 10.1016/j.celrep.2017.11.011] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2017] [Revised: 06/28/2017] [Accepted: 11/01/2017] [Indexed: 12/31/2022] Open
Abstract
Erythropoiesis is a highly regulated process that generates enucleate red blood cells from committed erythroid progenitors. Chromatin condensation culminating in enucleation is a defining feature of this process. Setd8 is the sole enzyme that can mono-methylate histone H4, lysine 20 and is highly expressed in erythroblasts compared to most other cell types. Erythroid Setd8 deletion results in embryonic lethality from severe anemia due to impaired erythroblast survival and proliferation. Setd8 protein levels are also uniquely regulated in erythroblasts, suggesting a cell-type-specific role for Setd8 during terminal maturation. Consistent with this hypothesis, Setd8 Δ/Δ erythroblasts have profound defects in transcriptional repression, chromatin condensation, and heterochromatin accumulation. Together, these results suggest that Setd8, used by most cells to promote mitotic chromatin condensation, is an essential aspect of the transcriptional repression and chromatin condensation that are hallmarks of terminal erythroid maturation.
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Affiliation(s)
- Jeffrey Malik
- Department of Pediatrics, University of Rochester, Rochester, NY 14620, USA
| | - Jacquelyn A Lillis
- Department of Pediatrics, University of Rochester, Rochester, NY 14620, USA; Genomics Research Center, University of Rochester, Rochester, NY 14620, USA
| | - Tyler Couch
- Department of Pediatrics, University of Rochester, Rochester, NY 14620, USA
| | - Michael Getman
- Department of Pediatrics, University of Rochester, Rochester, NY 14620, USA
| | - Laurie A Steiner
- Department of Pediatrics, University of Rochester, Rochester, NY 14620, USA.
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17
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Steiner LA, Schulz V, Makismova Y, Lezon-Geyda K, Gallagher PG. CTCF and CohesinSA-1 Mark Active Promoters and Boundaries of Repressive Chromatin Domains in Primary Human Erythroid Cells. PLoS One 2016; 11:e0155378. [PMID: 27219007 PMCID: PMC4878738 DOI: 10.1371/journal.pone.0155378] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2016] [Accepted: 04/27/2016] [Indexed: 01/20/2023] Open
Abstract
Background CTCF and cohesinSA-1 are regulatory proteins involved in a number of critical cellular processes including transcription, maintenance of chromatin domain architecture, and insulator function. To assess changes in the CTCF and cohesinSA-1 interactomes during erythropoiesis, chromatin immunoprecipitation coupled with high throughput sequencing and mRNA transcriptome analyses via RNA-seq were performed in primary human hematopoietic stem and progenitor cells (HSPC) and primary human erythroid cells from single donors. Results Sites of CTCF and cohesinSA-1 co-occupancy were enriched in gene promoters in HSPC and erythroid cells compared to single CTCF or cohesin sites. Cell type-specific CTCF sites in erythroid cells were linked to highly expressed genes, with the opposite pattern observed in HSPCs. Chromatin domains were identified by ChIP-seq with antibodies against trimethylated lysine 27 histone H3, a modification associated with repressive chromatin. Repressive chromatin domains increased in both number and size during hematopoiesis, with many more repressive domains in erythroid cells than HSPCs. CTCF and cohesinSA-1 marked the boundaries of these repressive chromatin domains in a cell-type specific manner. Conclusion These genome wide data, changes in sites of protein occupancy, chromatin architecture, and related gene expression, support the hypothesis that CTCF and cohesinSA-1 have multiple roles in the regulation of gene expression during erythropoiesis including transcriptional regulation at gene promoters and maintenance of chromatin architecture. These data from primary human erythroid cells provide a resource for studies of normal and perturbed erythropoiesis.
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Affiliation(s)
- Laurie A Steiner
- Department of Pediatrics, University of Rochester, Rochester, New York, United States of America
| | - Vincent Schulz
- Department of Pediatrics, Yale University School of Medicine, New Haven, Connecticut, United States of America
| | - Yelena Makismova
- Department of Pediatrics, Yale University School of Medicine, New Haven, Connecticut, United States of America
| | - Kimberly Lezon-Geyda
- Department of Pediatrics, Yale University School of Medicine, New Haven, Connecticut, United States of America
| | - Patrick G Gallagher
- Department of Pediatrics, Yale University School of Medicine, New Haven, Connecticut, United States of America.,Departments of Pathology and Genetics, Yale University School of Medicine, New Haven, Connecticut, United States of America
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Li Y, Schulz VP, Deng C, Li G, Shen Y, Tusi BK, Ma G, Stees J, Qiu Y, Steiner LA, Zhou L, Zhao K, Bungert J, Gallagher PG, Huang S. Setd1a and NURF mediate chromatin dynamics and gene regulation during erythroid lineage commitment and differentiation. Nucleic Acids Res 2016; 44:7173-88. [PMID: 27141965 PMCID: PMC5009724 DOI: 10.1093/nar/gkw327] [Citation(s) in RCA: 33] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2015] [Accepted: 04/15/2016] [Indexed: 01/08/2023] Open
Abstract
The modulation of chromatin structure is a key step in transcription regulation in mammalian cells and eventually determines lineage commitment and differentiation. USF1/2, Setd1a and NURF complexes interact to regulate chromatin architecture in erythropoiesis, but the mechanistic basis for this regulation is hitherto unknown. Here we showed that Setd1a and NURF complexes bind to promoters to control chromatin structural alterations and gene activation in a cell context dependent manner. In human primary erythroid cells USF1/2, H3K4me3 and the NURF complex were significantly co-enriched at transcription start sites of erythroid genes, and their binding was associated with promoter/enhancer accessibility that resulted from nucleosome repositioning. Mice deficient for Setd1a, an H3K4 trimethylase, in the erythroid compartment exhibited reduced Ter119/CD71 positive erythroblasts, peripheral blood RBCs and hemoglobin levels. Loss of Setd1a led to a reduction of promoter-associated H3K4 methylation, inhibition of gene transcription and blockade of erythroid differentiation. This was associated with alterations in NURF complex occupancy at erythroid gene promoters and reduced chromatin accessibility. Setd1a deficiency caused decreased associations between enhancer and promoter looped interactions as well as reduced expression of erythroid genes such as the adult β-globin gene. These data indicate that Setd1a and NURF complexes are specifically targeted to and coordinately regulate erythroid promoter chromatin dynamics during erythroid lineage differentiation.
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Affiliation(s)
- Ying Li
- Department of Biochemistry and Molecular Biology, University of Florida College of Medicine, Gainesville, FL 32610, USA Macau Institute for Applied Research in Medicine and Health, State Key laboratory of Quality Research in Chinese Medicine, Macau University of Science and Technology, Avenida Wai Long, Taipa, Macau 519020, China
| | - Vincent P Schulz
- Department of Pediatrics, Pathology, and Genetics, Yale University School of Medicine, New Haven, CT 06520, USA
| | - Changwang Deng
- Department of Biochemistry and Molecular Biology, University of Florida College of Medicine, Gainesville, FL 32610, USA
| | - Guangyao Li
- Department of Molecular Genetics and Microbiology, University of Florida College of Medicine, Gainesville, FL 32610, USA
| | - Yong Shen
- Department of Biochemistry and Molecular Biology, University of Florida College of Medicine, Gainesville, FL 32610, USA
| | - Betsabeh K Tusi
- Department of Biochemistry and Molecular Biology, University of Florida College of Medicine, Gainesville, FL 32610, USA
| | - Gina Ma
- Public Health Studies, The Johns Hopkins University, Baltimore, MD 21218, USA
| | - Jared Stees
- Department of Biochemistry and Molecular Biology, University of Florida College of Medicine, Gainesville, FL 32610, USA
| | - Yi Qiu
- Department of Anatomy and Cell Biology, University of Florida College of Medicine, Gainesville, FL 32610, USA Genetics Institute, University of Florida, Gainesville, FL 32610, USA UF health Cancer center, University of Florida College of Medicine, Gainesville, FL 32610, USA
| | - Laurie A Steiner
- Department of Pediatrics, University of Rochester, Rochester, NY 14642, USA
| | - Lei Zhou
- Department of Molecular Genetics and Microbiology, University of Florida College of Medicine, Gainesville, FL 32610, USA Genetics Institute, University of Florida, Gainesville, FL 32610, USA UF health Cancer center, University of Florida College of Medicine, Gainesville, FL 32610, USA
| | - Keji Zhao
- Systems Biology Center, NHLBI, National Institute of Health, Bethesda, MD 20814, USA
| | - Jörg Bungert
- Department of Biochemistry and Molecular Biology, University of Florida College of Medicine, Gainesville, FL 32610, USA Genetics Institute, University of Florida, Gainesville, FL 32610, USA
| | - Patrick G Gallagher
- Department of Pediatrics, Pathology, and Genetics, Yale University School of Medicine, New Haven, CT 06520, USA
| | - Suming Huang
- Department of Biochemistry and Molecular Biology, University of Florida College of Medicine, Gainesville, FL 32610, USA Macau Institute for Applied Research in Medicine and Health, State Key laboratory of Quality Research in Chinese Medicine, Macau University of Science and Technology, Avenida Wai Long, Taipa, Macau 519020, China Genetics Institute, University of Florida, Gainesville, FL 32610, USA UF health Cancer center, University of Florida College of Medicine, Gainesville, FL 32610, USA
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Su MY, Steiner LA, Bogardus H, Mishra T, Schulz VP, Hardison RC, Gallagher PG. Identification of biologically relevant enhancers in human erythroid cells. J Biol Chem 2013; 288:8433-8444. [PMID: 23341446 DOI: 10.1074/jbc.m112.413260] [Citation(s) in RCA: 43] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023] Open
Abstract
Identification of cell type-specific enhancers is important for understanding the regulation of programs controlling cellular development and differentiation. Enhancers are typically marked by the co-transcriptional activator protein p300 or by groups of cell-expressed transcription factors. We hypothesized that a unique set of enhancers regulates gene expression in human erythroid cells, a highly specialized cell type evolved to provide adequate amounts of oxygen throughout the body. Using chromatin immunoprecipitation followed by massively parallel sequencing, genome-wide maps of candidate enhancers were constructed for p300 and four transcription factors, GATA1, NF-E2, KLF1, and SCL, using primary human erythroid cells. These data were combined with gene expression analyses, and candidate enhancers were identified. Consistent with their predicted function as candidate enhancers, there was statistically significant enrichment of p300 and combinations of co-localizing erythroid transcription factors within 1-50 kb of the transcriptional start site (TSS) of genes highly expressed in erythroid cells. Candidate enhancers were also enriched near genes with known erythroid cell function or phenotype. Candidate enhancers exhibited moderate conservation with mouse and minimal conservation with nonplacental vertebrates. Candidate enhancers were mapped to a set of erythroid-associated, biologically relevant, SNPs from the genome-wide association studies (GWAS) catalogue of NHGRI, National Institutes of Health. Fourteen candidate enhancers, representing 10 genetic loci, mapped to sites associated with biologically relevant erythroid traits. Fragments from these loci directed statistically significant expression in reporter gene assays. Identification of enhancers in human erythroid cells will allow a better understanding of erythroid cell development, differentiation, structure, and function and provide insights into inherited and acquired hematologic disease.
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Affiliation(s)
- Mack Y Su
- Department of Pediatrics, Yale University School of Medicine, New Haven, Connecticut 06520
| | - Laurie A Steiner
- Department of Pediatrics, University of Rochester, Rochester, New York 14642
| | - Hannah Bogardus
- Department of Pediatrics, Yale University School of Medicine, New Haven, Connecticut 06520
| | - Tejaswini Mishra
- Department of Biochemistry and Molecular Biology, Center for Comparative Genomics and Bioinformatics, Pennsylvania State University, University Park, Pennsylvania 16802
| | - Vincent P Schulz
- Department of Pediatrics, Yale University School of Medicine, New Haven, Connecticut 06520
| | - Ross C Hardison
- Department of Biochemistry and Molecular Biology, Center for Comparative Genomics and Bioinformatics, Pennsylvania State University, University Park, Pennsylvania 16802
| | - Patrick G Gallagher
- Department of Pediatrics, Yale University School of Medicine, New Haven, Connecticut 06520; Departments of Pathology and Genetics, Yale University School of Medicine, New Haven, Connecticut 06520.
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20
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Steiner LA, Schulz VP, Maksimova Y, Wong C, Gallagher PG. Patterns of histone H3 lysine 27 monomethylation and erythroid cell type-specific gene expression. J Biol Chem 2011; 286:39457-65. [PMID: 21937433 DOI: 10.1074/jbc.m111.243006] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022] Open
Abstract
Post-translational histone modifications, acting alone or in a context-dependent manner, influence numerous cellular processes via their regulation of gene expression. Monomethylation of histone H3 lysine 27 (K27me1) is a poorly understood histone modification. Some reports describe depletion of K27Me1 at promoters and transcription start sites (TSS), implying its depletion at TSS is necessary for active transcription, while others have associated enrichment of H3K27me1 at TSS with increased levels of mRNA expression. Tissue- and gene-specific patterns of H3K27me1 enrichment and their correlation with gene expression were determined via chromatin immunoprecipitation on chip microarray (ChIP-chip) and human mRNA expression array analyses. Results from erythroid cells were compared with those in neural and muscle cells. H3K27me1 enrichment varied depending on levels of cell-type specific gene expression, with highest enrichment over transcriptionally active genes. Over individual genes, the highest levels of H3K27me1 enrichment were found over the gene bodies of highly expressed genes. In contrast to H3K4me3, which was highly enriched at the TSS of actively transcribing genes, H3K27me1 was selectively depleted at the TSS of actively transcribed genes. There was markedly decreased to no H3K27me1 enrichment in genes with low expression. At some locations, H3K27 monomethylation was also found to be associated with chromatin signatures of gene enhancers.
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Affiliation(s)
- Laurie A Steiner
- Department of Pediatrics, Yale University School of Medicine, New Haven, Connecticut 06520, USA
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21
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Burkhart CS, Rossi A, Dell-Kuster S, Gamberini M, Möckli A, Siegemund M, Czosnyka M, Strebel SP, Steiner LA. Effect of age on intraoperative cerebrovascular autoregulation and near-infrared spectroscopy-derived cerebral oxygenation. Br J Anaesth 2011; 107:742-8. [PMID: 21835838 DOI: 10.1093/bja/aer252] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
BACKGROUND Age is an important risk factor for perioperative cerebral complications such as stroke, postoperative cognitive dysfunction, and delirium. We explored the hypothesis that intraoperative cerebrovascular autoregulation is less efficient and brain tissue oxygenation lower in elderly patients, thus, increasing the vulnerability of elderly brains to systemic insults such as hypotension. METHODS We monitored intraoperative cerebral perfusion in 50 patients aged 18-40 and 77 patients >65 yr at two Swiss university hospitals. Mean arterial pressure (MAP) was measured continuously using a plethysmographic method. An index of cerebrovascular autoregulation (Mx) was calculated based on changes in transcranial Doppler flow velocity due to changes in MAP. Cerebral oxygenation was assessed by the tissue oxygenation index (TOI) using near-infrared spectroscopy. End-tidal CO₂, O₂, and sevoflurane concentrations and peripheral oxygen saturation were recorded continuously. Standardized anaesthesia was administered in all patients (thiopental, sevoflurane, fentanyl, atracurium). RESULTS Autoregulation was less efficient in patients aged >65 yr [by 0.10 (se 0.04; P=0.020)] in a multivariable linear regression analysis. This difference was not attributable to differences in MAP, end-tidal CO₂, or higher doses of sevoflurane. TOI was not significantly associated with age, sevoflurane dose, or Mx but increased with increasing flow velocity [by 0.09 (se 0.04; P=0.028)] and increasing MAP [by 0.11 (se 0.05; P=0.043)]. CONCLUSIONS Our results do not support the hypothesis that older patients' brains are more vulnerable to systemic insults. The difference of autoregulation between the two groups was small and most likely clinically insignificant.
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Affiliation(s)
- C S Burkhart
- Department of Anaesthesia and Intensive Care Medicine, University Hospital Basel, Switzerland
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22
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Abstract
The objective of this study was to examine the use of partial exchange transfusion (PET) performed for polycythemia hyperviscosity syndrome (PHS) over time. A retrospective review of 141 infants who received a PET for PHS at Yale-New Haven Hospital between 1986 and 2007 was performed, querying maternal and neonatal medical records. Patient demographics, risk factors for PHS, indications for PET, and complications associated with PET and PHS were collected. Overall, there was no change in the number of PET performed over the study period ( R(2)=0.082, P=0.192). Eighty-eight percent of patients had at least one risk factor for PHS, most commonly maternal diabetes. Over time, there was a statistically significant decrease in maternal diabetes as a risk factor for PHS. Forty percent of patients had a significant complication attributed to PHS prior to PET. Eighteen percent of patients had a complication attributed to PET. Life-threatening complications of PHS or PET were rare. In conclusion, PHS continues to be a problem observed in neonatal intensive care units, particularly in at-risk populations. PHS and PET are associated with significant complications. Well-designed studies with long-term follow up are needed to assess the risks and benefits of PET for PHS.
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Affiliation(s)
- Bridget Hopewell
- Yale University School of Medicine, Yale University School of Medicine, 333 Cedar Street, New Haven, CT 06520, USA
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23
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Abstract
Defects in mevalonate kinase, a critical rate-limiting enzyme in cholesterol and isoprene metabolism, have been associated with 2 clinical phenotypes: mevalonic aciduria, which presents in infancy or early childhood with growth failure, dysmorphic features, and neurologic disease; and hyperimmunoglobulinemia D and periodic fever syndrome, which usually presents outside the neonatal period as an autoinflammatory periodic fever syndrome. This report describes a kindred with 2 siblings affected by severe mevalonate kinase deficiency (mevalonic aciduria) with perinatal onset. Dysmorphic and central nervous system abnormalities, anemia, and cholestasis were prominent features in 1 sibling. Both cases were fatal, 1 in the immediate neonatal period and 1 in utero. The small number of cases of mevalonate kinase deficiency presenting in the perinatal period have typically been severely affected, with signs and symptoms of a severe multisystem disorder. Predominant features of perinatal onset mevalonate kinase deficiency include intrauterine growth restriction, cerebral ventriculomegaly, dysmorphic features, skeletal abnormalities, dyserythropoietic anemia with extramedullary erythropoiesis, thrombocytopenia, cholestatic liver disease, persistent diarrhea, renal failure, recurrent sepsis-like episodes, and failure to thrive. Clinical findings may mimic severe intrauterine viral infection, a chromosomal abnormality, or an acute sepsis syndrome, potentially contributing to delays in diagnosis of this rare condition. Perinatal onset mevalonate kinase deficiency is associated with a very poor prognosis, with death in utero or in early infancy. Detailed autopsy findings in mevalonate kinase deficiency have rarely been reported.
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Affiliation(s)
- Laurie A Steiner
- Department of Pediatrics, Yale University School of Medicine, New Haven, CT, USA
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24
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Gallagher PG, Steiner LA, Liem RI, Owen AN, Cline AP, Seidel NE, Garrett LJ, Bodine DM. Mutation of a barrier insulator in the human ankyrin-1 gene is associated with hereditary spherocytosis. J Clin Invest 2010; 120:4453-65. [PMID: 21099109 DOI: 10.1172/jci42240] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/07/2010] [Accepted: 09/22/2010] [Indexed: 11/17/2022] Open
Abstract
Defects of the ankyrin-1 gene are the most common cause in humans of hereditary spherocytosis, an inherited anemia that affects patients of all ethnic groups. In some kindreds, linked -108/-153 nucleotide substitutions have been found in the upstream region of the ankyrin gene promoter that is active in erythroid cells. In vivo, the ankyrin erythroid promoter and its upstream region direct position-independent, uniform expression, a property of barrier insulators. Using human erythroid cell lines and primary cells and transgenic mice, here we have demonstrated that a region upstream of the erythroid promoter is a barrier insulator in vivo in erythroid cells. The region exhibited both functional and structural characteristics of a barrier, including prevention of gene silencing in an in vivo functional assay, appropriate chromatin configuration, and occupancy by barrier-associated proteins. Fragments with the -108/-153 spherocytosis-associated mutations failed to function as barrier insulators in vivo and demonstrated perturbations in barrier-associated chromatin configuration. In transgenic mice, flanking a mutant -108/-153 ankyrin gene promoter with the well-characterized chicken HS4 barrier insulator restored position-independent, uniform expression at levels comparable to wild-type. These data indicate that an upstream region of the ankyrin-1 erythroid promoter acts as a barrier insulator and identify disruption of the barrier element as a potential pathogenetic mechanism of human disease.
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Affiliation(s)
- Patrick G Gallagher
- Departments of Pediatrics, Yale University School of Medicine, New Haven, Connecticut, USA.
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25
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Williams JC, Steiner LA, Ogden RC, Simon MI, Feher G. Primary structure of the M subunit of the reaction center from Rhodopseudomonas sphaeroides. Proc Natl Acad Sci U S A 2010; 80:6505-9. [PMID: 16593385 PMCID: PMC390381 DOI: 10.1073/pnas.80.21.6505] [Citation(s) in RCA: 142] [Impact Index Per Article: 10.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
The reaction center is a membrane-bound bacteriochlorophyll-protein complex that mediates the primary photochemical events in the photosynthetic bacterium Rhodopseudomonas sphaeroides. The previously determined amino-terminal sequences of the three subunits of the reaction center protein were used to design synthetic mixed oligonucleotide probes for the structural genes encoding the subunits. One of these probes was used to isolate and clone a fragment of DNA from R. sphaeroides that contained the gene encoding the M subunit. The nucleotide sequence of this gene was determined by the dideoxy method. In addition, a number of tryptic and chymotryptic peptides from the M protein were isolated and subjected to sequence analysis, and the sequence of the carboxyl terminus was determined. Together with the amino-terminal sequence, the data establish the primary structure of the M protein. The distribution of hydrophobic residues in the amino acid sequence suggests the presence of five membrane-spanning segments. A significant homology was found between the amino acid sequence of the M subunit and a thylakoid membrane protein (M(r) 32,000) from spinach that has been implicated in herbicide and quinone binding.
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Affiliation(s)
- J C Williams
- Department of Biology, University of California, San Diego, La Jolla, CA 92093
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26
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Burkhart CS, Siegemund M, Strebel SP, Steiner LA. Effect of n-3 fatty acids on cerebral markers and the inflammatory response in sepsis. Crit Care 2010. [PMCID: PMC2934335 DOI: 10.1186/cc8793] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
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Steiner LA, Van Hoff J, Kutlar F, Gallagher PG. Aplastic Crisis Revealing the Diagnosis of Hb Evans [α62(E11)Val→Met,GTG→ATG (α2)] in a Hispanic Kindred: Case Report and Review. Hemoglobin 2009; 31:409-16. [DOI: 10.1080/03630260701590301] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
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Ruppen W, Steiner LA, Drewe J, Hauenstein L, Brugger S, Seeberger MD. Bupivacaine concentrations in the lumbar cerebrospinal fluid of patients during spinal anaesthesia. Br J Anaesth 2009; 102:832-8. [PMID: 19329470 DOI: 10.1093/bja/aep049] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
BACKGROUND Data on bupivacaine concentrations in the cerebral spinal fluid (CSF) during spinal anaesthesia are scarce. The purpose of this study was to determine the concentration of bupivacaine in the lumbar CSF of patients with an adequate level of spinal anaesthesia after injection of plain bupivacaine 0.5%. METHODS Sixty patients with an adequate level of spinal block after standardized administration of plain bupivacaine 20 mg in men and of 17.5 mg in women were studied. To measure the CSF bupivacaine concentration, we performed a second lumbar spinal puncture and obtained a CSF sample at a randomized time point 5-45 min after the bupivacaine injection. In addition, we calculated the half-life of bupivacaine in the CSF and tested the hypothesis that the level of spinal block is related to the lumbar CSF bupivacaine concentration. RESULTS Men and women had CSF bupivacaine concentrations ranging from 95.4 to 773.0 microg ml(-1) (median 242.4 microg ml(-1)) and from 25.9 to 781.0 microg ml(-1) (median 187.6 microg ml(-1)), respectively. The large variability of bupivacaine concentrations obtained at similar times after subarachnoid administration made calculation of a meaningful half-life of bupivacaine in CSF impossible. There was no association between CSF bupivacaine concentration and spinal block level, and CSF bupivacaine concentrations for the same spinal block level differed between patients by six-fold. CONCLUSIONS There is a large variability of CSF bupivacaine concentrations in patients with an adequate level of spinal anaesthesia.
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Affiliation(s)
- W Ruppen
- Department of Anaesthesia, University Hospital Basel, Spitalstrasse 21, Basel CH-4031, Switzerland
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Di Terlizzi R, Gallagher PG, Mohandas N, Steiner LA, Dolce KS, Guo X, Wilkerson MJ, Stockham SL. Canine elliptocytosis due to a mutant beta-spectrin. Vet Clin Pathol 2009; 38:52-8. [PMID: 19228356 DOI: 10.1111/j.1939-165x.2008.00092.x] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
A 5-year-old, spayed female, mixed-breed dog with persistent elliptocytosis was evaluated at the Veterinary Medical Teaching Hospital at Kansas State University. The elliptocytosis was asymptomatic and was detected during the evaluation of lameness. When subjected to shear stress in an ektacytometer, the dog's erythrocytes had reduced cellular deformability and erythrocyte membranes had decreased mechanical stability. Analysis of erythrocyte membrane spectrin by nondenaturing gel electrophoresis revealed an increased amount of spectrin dimers, indicating a defect in spectrin self-association. DNA analysis detected a beta-spectrin mutation in codon 2110 in which threonine was replaced by methionine. This mutation likely altered the molecular structure of the erythrocyte membrane, leading to impaired spectrin self-association and elliptocyte formation.
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Abstract
Anemia is a commonly encountered problem in the fetal and neonatal period, and can lead to significant morbidity and mortality. Intrinsic disorders of the erythrocyte, such as the hemoglobinopathies, enzyme deficiencies, and membrane defects are common causes of neonatal anemia. Genetic diseases that lead to decreased erythrocyte production, such as Diamond-Blackfan anemia, Schwachman-Diamond syndrome, and Congential Dyserythropoietic Anemia, are rare causes of perinatal anemia, but are important to recognize as they are often associated with other congenital abnormalities and require specialized treatment. This review focuses on the perinatal presentation and management of intrinsic erythrocyte disorders, as well as on the diagnosis and management of genetic conditions leading to erythrocyte underproduction.
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Affiliation(s)
- Laurie A Steiner
- Division of Perinatal Medicine, Department of Pediatrics, Yale University School of Medicine, New Haven, CT 06520-8064, USA.
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31
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Steiner LA, Bizzarro MJ, Ehrenkranz RA, Gallagher PG. A decline in the frequency of neonatal exchange transfusions and its effect on exchange-related morbidity and mortality. Pediatrics 2007; 120:27-32. [PMID: 17606558 DOI: 10.1542/peds.2006-2910] [Citation(s) in RCA: 101] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
Abstract
OBJECTIVE Our goal was to identify trends in patient demographics and indications for and complications related to neonatal exchange transfusion over a 21-year period in a single institution using a uniform protocol for performing the procedure. METHODS A retrospective chart review of 107 patients who underwent 141 single- or double-volume exchange transfusions from 1986-2006 was performed. Patients were stratified into 2 groups, 1986-1995 and 1996-2006, on the basis of changes in clinical practice influenced by American Academy of Pediatrics management guidelines for hyperbilirubinemia. RESULTS There was a marked decline in the frequency of exchange transfusions per 1000 newborn special care unit admissions over the 21-year study period. Patient demographics and indications for exchange transfusion were similar between groups. A significantly higher proportion of patients in the second time period received intravenous immunoglobulin before exchange transfusion. There was a higher proportion of patients in the 1996-2006 group with a serious underlying condition at the time of exchange transfusion. During that same time period, a lower proportion of patients experienced an adverse event related to the exchange transfusion. Although a similar percentage of patients in both groups experienced hypocalcemia and thrombocytopenia after exchange transfusion, patients treated from 1996-2006 were significantly more likely to receive calcium replacement or platelet transfusion. No deaths were related to exchange transfusion in either time period. CONCLUSIONS Improvements in prenatal and postnatal care have led to a sharp decline in the number of exchange transfusions performed. This decline has not led to an increase in complications despite relative inexperience with the procedure.
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Affiliation(s)
- Laurie A Steiner
- Department of Pediatrics, Yale University School of Medicine, 333 Cedar St, PO Box 208064, New Haven, CT 06520-8064, USA
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Bolliger D, Steiner LA, Kasper J, Aziz OA, Filipovic M, Seeberger MD. The accuracy of non-invasive carbon dioxide monitoring: a clinical evaluation of two transcutaneous systems. Anaesthesia 2007; 62:394-9. [PMID: 17381578 DOI: 10.1111/j.1365-2044.2007.04987.x] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.4] [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: 11/28/2022]
Abstract
We determined the accuracy of two transcutaneous carbon dioxide monitoring systems (SenTec Digital Monitor with V-Sign Sensor and TOSCA 500 with TOSCA Sensor 92) for the measurement of single values and trends in the arterial partial pressure of carbon dioxide in 122 adult patients during major surgery and in 50 adult patients in the intensive care unit. One or several paired measurements were performed in each patient. The first measurement was used to determine the accuracy of a single value of transcutaneous carbon dioxide; the difference between the first and the last measurements was used to analyse the accuracy and to track trends. We defined a 95% limit of agreement of <or=1 kPa as being clinically useful. There was insufficient agreement between transcutaneous carbon dioxide partial pressure values derived from the two systems and arterial carbon dioxide values for both single values and trends as defined by our suggested limit of agreement. We conclude that these systems cannot replace conventional blood gas analysis in the clinical setting studied.
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Affiliation(s)
- D Bolliger
- Department of Anaesthesia and Intensive Care Unit, University of Basel Hospital, CH-4031 Basel, Switzerland.
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Steiner LA, Staender S, Sieber CC, Skarvan K. Effects of simulated hypovolaemia on haemodynamics, left ventricular function, mesenteric blood flow and gastric Pco2. Acta Anaesthesiol Scand 2007; 51:143-50. [PMID: 17261143 DOI: 10.1111/j.1399-6576.2006.01219.x] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
BACKGROUND Compensated clinically silent hypovolaemia may lead to low cardiac output, hypoperfusion and ischaemia. We investigated the cardiovascular effects of simulated hypovolaemia to determine whether it caused mesenteric ischaemia detectable by gastric tonometry. METHODS Thirteen healthy volunteers, aged 21-36 years, were investigated. Lower body negative pressure (LBNP) was used to simulate normotensive hypovolaemia. Cardiovascular parameters were measured using echocardiography. Mesenteric blood flow was investigated using Doppler sonography of the superior mesenteric artery (SMA). Gastric Pco(2) (P(g)co(2)) was measured using gas tonometry. Data were collected at baseline, LBNP and during a recovery period. RESULTS Normotensive hypovolaemia was induced successfully in 11 volunteers. There were no significant differences in mean arterial pressure between the three data points (91 +/- 6, 93 +/- 10 and 95 +/- 9 mmHg, respectively). With the induction of LBNP, the heart rate increased from 64 +/- 16 to 73 +/- 16 beats/min (P < 0.001), the cardiac index decreased from 2.7 +/- 1.0 to 1.8 +/- 0.6 l/min/m(2) (P= 0.002) and the systemic vascular resistance increased from 1535 +/- 445 to 2270 +/- 550 dyn s/cm(5) (P < 0.001). The SMA mean flow velocity decreased from 53 +/- 18 to 37 +/- 20 cm/s (69 +/- 20%) (P= 0.007), and increased to 56 +/- 34 cm/s (106 +/- 38%) (P= 0.001) during reperfusion. The SMA resistance increased from 92 +/- 30 to 174 +/- 110 mmHg/l/min (P= 0.004). These changes were reversible after termination of LBNP. By contrast, there were no significant differences in P(g)co(2) between the three data points. CONCLUSIONS In these volunteers, the mesenteric vascular bed contributed importantly to the maintenance of arterial pressure during normotensive hypovolaemia. However, this compensated hypovolaemia did not compromise the mesenteric perfusion sufficiently to increase P(g)co(2) and to allow detection by tonometry.
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Affiliation(s)
- L A Steiner
- Department of Anaesthesia, University Hospital Basel, Basel, Switzerland.
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Abstract
Raised intracranial pressure (ICP) and low cerebral blood flow (CBF) are associated with ischaemia and poor outcome after brain injury. Therefore, many management protocols target these parameters. This overview summarizes the technical aspects of ICP and CBF monitoring, and their role in the clinical management of brain-injured patients. Furthermore, some applications of these methods in current research are highlighted. ICP is typically measured using probes that are inserted into one of the lateral ventricles or the brain parenchyma. Therapeutic measures used to control ICP have relevant side-effects and continuous monitoring is essential to guide such therapies. ICP is also required to calculate cerebral perfusion pressure which is one of the most important therapeutic targets in brain-injured patients. Several bedside CBF monitoring devices are available. However, most do not measure CBF but rather a parameter that is thought to be proportional to CBF. Frequently used methods include transcranial Doppler which measures blood flow velocity and may be helpful for the diagnosis and monitoring of cerebral vasospasm after subarachnoid haemorrhage or jugular bulb oximetry which gives information on adequacy of CBF in relation to the metabolic demand of the brain. However, there is no clear evidence that incorporating data from CBF monitors into our management strategies improves outcome in brain-injured patients.
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Affiliation(s)
- L A Steiner
- Surgical Intensive Care Unit, Department of Anaesthesia, University Hospital Basel, CH-4031 Basel, Switzerland.
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Pickard JD, Hutchinson PJ, Coles JP, Steiner LA, Johnston AJ, Fryer TD, Coleman MR, Smielewski P, Chatfield DA, Aigbirhio F, Williams GB, Rice K, Clark JC, Salmond CH, Sahakian BJ, Bradley PG, Carpenter TA, Salvador R, Pena A, Gillard JH, Cunningham AS, Piechnik S, Czosnyka M, Menon DK. Imaging of cerebral blood flow and metabolism in brain injury in the ICU. Acta Neurochir Suppl 2006; 95:459-64. [PMID: 16463901 DOI: 10.1007/3-211-32318-x_94] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 03/07/2023]
Abstract
The heterogeneity of the initial insult and subsequent pathophysiology has made both the study of human head injury and design of randomised controlled trials exceptionally difficult. The combination of multimodality bedside monitoring and functional brain imaging positron emission tomography (PET) and magnetic resonance (MR), incorporated within a Neurosciences Critical Care Unit, provides the resource required to study critically ill patients after brain injury from initial ictus through recovery from coma and rehabilitation to final outcome. Methods to define cerebral ischemia in the context of altered cerebral oxidative metabolism have been developed, traditional therapies for intracranial hypertension re-evaluated and bedside monitors cross-validated. New modelling and analytical approaches have been developed.
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Affiliation(s)
- J D Pickard
- Wolfson Brain Imaging Centre, University of Cambridge, Addenbrookes Hospital, Cambridge, UK.
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Steiner LA. ["Postoperative cognitive dysfunction--do anaesthetics harm memory?"]. Praxis (Bern 1994) 2005; 94:1811-4. [PMID: 16329402 DOI: 10.1024/0369-8394.94.46.1811] [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] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/05/2023]
Abstract
Nach Operationen können zwei Formen von kognitiven Störungen auftreten: Das postoperative Delir und die postoperative kognitive Dysfunktion. Letztere äussert sich durch diskrete Störungen des Gedächtnisses, der Aufmerksamkeit und der Sprache, die während Monaten persistieren können. Die wichtigsten Risikofaktoren für die Entwicklung der postoperativen kognitiven Dysfunktion sind ein höheres Alter und die Art des Eingriffs. Bei Patienten, die älter als 60 Jahre alt sind, kann bei rund 25% eine Woche nach einem grösseren Eingriff eine postoperative kognitive Dysfunktion festgestellt werden, drei Monate postoperativ bei 10%. Nach herzchirurgischen Eingriffen ist die Inzidenz noch höher: Bei rund der Hälfte der Patienten kann bei Spitalaustritt eine postoperative kognitive Dysfunktion festgestellt werden, nach sechs Monaten noch bei einem Viertel. Die Pathogenese und die Rolle der Anästhesie bei der Entwicklung der postoperativen kognitiven Dysfunktion sind unklar. Es gibt keine Studien, die den Effekt der Anästhesie unabhängig von einer Operation oder einer Hospitalisation untersuchen. Weder neuere, kurzwirksame Medikamente noch die Wahl der Anästhesietechnik (Regionalanästhesie oder Allgemeinanästhesie) können die postoperative kognitive Dysfunktion verhindern. Eine Prophylaxe oder Therapie ist zum jetzigen Zeitpunkt nicht bekannt.
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Affiliation(s)
- L A Steiner
- Departement Anästhesie, Universitätsspital Basel
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Cunningham AS, Salvador R, Coles JP, Chatfield DA, Bradley PG, Johnston AJ, Steiner LA, Fryer TD, Aigbirhio FI, Smielewski P, Williams GB, Carpenter TA, Gillard JH, Pickard JD, Menon DK. Physiological thresholds for irreversible tissue damage in contusional regions following traumatic brain injury. Brain 2005; 128:1931-42. [PMID: 15888537 DOI: 10.1093/brain/awh536] [Citation(s) in RCA: 107] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Cerebral ischaemia appears to be an important mechanism of secondary neuronal injury in traumatic brain injury (TBI) and is an important predictor of outcome. To date, the thresholds of cerebral blood flow (CBF) and cerebral oxygen utilization (CMRO(2)) for irreversible tissue damage used in TBI studies have been adopted from experimental and clinical ischaemic stroke studies. Identification of irreversibly damaged tissue in the acute phase following TBI could have considerable therapeutic and prognostic implications. However, it is questionable whether stroke thresholds are applicable to TBI. Therefore, the aim of this study was to determine physiological thresholds for the development of irreversible tissue damage in contusional and pericontusional regions in TBI, and to determine the ability of such thresholds to accurately differentiate irreversibly damaged tissue. This study involved 14 patients with structural abnormalities on late-stage MRI, all of whom had been studied with (15)O PET within 72 h of TBI. Lesion regions of interest (ROI) and non-lesion ROIs were constructed on late-stage MRIs and applied to co-registered PET maps of CBF, CMRO(2) and oxygen extraction fraction (OEF). From the entire population of voxels in non-lesion ROIs, we determined thresholds for the development of irreversible tissue damage as the lower limit of the 95% confidence interval for CBF, CMRO(2) and OEF. To test the ability of a physiological variable to differentiate lesion and non-lesion tissue, we constructed probability curves, demonstrating the ability of a physiological variable to predict lesion and non-lesion outcomes. The lower limits of the 95% confidence interval for CBF, CMRO(2) and OEF in non-lesion tissue were 15.0 ml/100 ml/min, 36.7 mumol/100 ml/min and 25.9% respectively. Voxels below these values were significantly more frequent in lesion tissue (all P < 0.005, Mann-Whitney U-test). However, a significant proportion of lesion voxels had values above these thresholds, so that definition of the full extent of irreversible tissue damage would not be possible based upon single physiological thresholds. We conclude that, in TBI, the threshold of CBF below which irreversible tissue damage consistently occurs differs from the classical CBF threshold for stroke (where similar methodology is used to define such thresholds). The CMRO(2) threshold is comparable to that reported in the stroke literature. At a voxel-based level, however (and in common with ischaemic stroke), the extent of irreversible tissue damage cannot be accurately predicted by early abnormalities of any single physiological variable.
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Affiliation(s)
- A S Cunningham
- Division of Anaesthesia, Department of Medicine, University of Cambridge, Cambridge, UK
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Steiner LA, Balestreri M, Johnston AJ, Coles JP, Smielewski P, Pickard JD, Menon DK, Czosnyka M. Predicting the response of intracranial pressure to moderate hyperventilation. Acta Neurochir (Wien) 2005; 147:477-83; discussion 483. [PMID: 15770347 DOI: 10.1007/s00701-005-0510-x] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/07/2004] [Accepted: 02/03/2005] [Indexed: 12/01/2022]
Abstract
BACKGROUND Hyperventilation may cause brain ischaemia after traumatic brain injury. However, moderate reductions in PaCO(2) are still an option in the management of raised intracranial pressure (ICP) under some circumstances. Being able to predict the ICP-response to such an intervention would be advantageous. We investigated the ability of pre-hyperventilation ICP and cerebrospinal compensatory reserve to predict the reduction in ICP achievable with moderate hyperventilation in head injured patients. METHODS Thirty head injured patients requiring sedation and mechanical ventilation were investigated. ICP was monitored via an intraparenchymal probe and intracranial cerebrospinal compensatory reserve was assessed using an index (R(ap)) based on the relationship between mean ICP and its pulse amplitude. Measurements were made at a constant level of PaCO(2) during a 20-minute baseline period. The patients were then subjected to an acute decrease in PaCO(2) of approximately 1 kPa and, after an equilibration period of 10 minutes, measurements were again made at a constant level of PaCO(2) for a further 20 minutes. A multiple linear regression model, incorporating baseline PaCO(2), ICP, and R(ap) was used to identify the relevant predictors of ICP reduction. FINDINGS Baseline ICP and R(ap) were both significant predictors of ICP-reduction (p=0.02 and 0.001 respectively) with R(ap) being the more powerful parameter. CONCLUSIONS A model based on cerebrospinal compensatory reserve and ICP can predict the achievable ICP-reduction and may potentially be used to optimise patient selection and intensity of hyperventilation.
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Affiliation(s)
- L A Steiner
- Academic Neurosurgery, Addenbrooke's Hospital, Cambridge, United Kingdom.
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Balestreri M, Czosnyka M, Steiner LA, Hiler M, Schmidt EA, Matta B, Menon D, Hutchinson P, Pickard JD. Association between outcome, cerebral pressure reactivity and slow ICP waves following head injury. Intracranial Pressure and Brain Monitoring XII 2005; 95:25-8. [PMID: 16463814 DOI: 10.1007/3-211-32318-x_6] [Citation(s) in RCA: 34] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/08/2023]
Abstract
OBJECTIVE To investigate the relationships between slow vasogenic waves ('B waves') of intracranial pressure (ICP), pressure-reactivity and outcome after traumatic brain injury. MATERIAL AND METHOD 193 head-injured patients (age 34 +/- 16.7 years; median GCS 6) were monitored from 1997 to 2002. ICP, arterial blood pressure (ABP) were continuously monitored. Pressure-reactivity index (PRx) and magnitude of ICP slow waves were evaluated using the bed-side computers. RESULTS Distribution of PRx in different outcome groups indicated that pressure-reactivity was significantly worse in patients with fatal outcome. A magnitude of spontaneous slow waves of ICP was gradually decreasing in poorer outcome grades. Mortality indicated threshold rise from 20% to 70% when averaged PRx increased above 0.3 (p < 0.01). There was no threshold for mortality observed along distribution of magnitude of ICP slow waves. Mortality gradually increased when the magnitude of slow waves decreased (R = -0.26; p < 0.0001). CONCLUSION Inadequate pressure-reactivity and low magnitude of slow vasogenic waves of ICP are associated with fatal outcome after head injury. Based on brain monitoring data, differentiation between favourable outcome and severe disability is more problematic than differentiation between survivors and non-survivors.
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Affiliation(s)
- M Balestreri
- Academic Neurosurgical Unit, Addenbrooke's Hospital, Cambridge, UK
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Steiner LA, Balestreri M, Johnston AJ, Coles JP, Chatfield DA, Pickard JD, Menon DK, Czosnyka M. Effects of moderate hyperventilation on cerebrovascular pressure-reactivity after head injury. Acta Neurochir Suppl 2005; 95:17-20. [PMID: 16463812 DOI: 10.1007/3-211-32318-x_4] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/06/2023]
Abstract
In volunteers, hyperventilation improves autoregulation. However, in head-injured patients, hyperventilation-induced deterioration and improvement of autoregulation have been reported. We have re-examined this question using an index of pressure reactivity. Thirty patients with severe or moderate head-injury were studied. Arterial blood pressure, cerebral perfusion pressure (CPP), and intracranial pressure (ICP) were recorded over 20 minute epochs separated by ten minutes of equilibration at baseline and during moderate (>3.5 kPa) hyperventilation. End-tidal CO2 was constant during each phase of data acquisition. Pressure reactivity was assessed using an index 'PRx' based on the response of ICP to spontaneous blood pressure changes. Hyperventilation decreased PaCO2 from 5.1 +/- 0.4 to 4.4 +/- 0.4 kPa (p < 0.0001). ICP decreased by 3.7 +/- 2.2 mmHg (p < 0.001). CPP increased by 5.9 +/- 8.2 mmHg (p < 0.001). Overall, PRx did not change significantly with hyperventilation. However, there was a significant negative correlation between baseline PRx and the change in PRx (r = -0.71, p < 0.0001). This suggests that patients with disturbed pressure-reactivity may improve, whereas patients with intact pressure reactivity remain largely unchanged. Our data suggest that the response of pressure reactivity to hyperventilation is heterogeneous. This could be due to hyperventilation-induced changes in cerebral metabolism, or the change in CPP.
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Affiliation(s)
- L A Steiner
- Academic Neurosurgery, Addenbrooke's Hospital, Cambridge, UK
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Balestreri M, Czosnyka M, Steiner LA, Schmidt E, Smielewski P, Matta B, Pickard JD. Intracranial hypertension: what additional information can be derived from ICP waveform after head injury? Acta Neurochir (Wien) 2004; 146:131-41. [PMID: 14963745 DOI: 10.1007/s00701-003-0187-y] [Citation(s) in RCA: 123] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
OBJECTIVE Although intracranial hypertension is one of the important prognostic factors after head injury, increased intracranial pressure (ICP) may also be observed in patients with favourable outcome. We have studied whether the value of ICP monitoring can be augmented by indices describing cerebrovascular pressure-reactivity and pressure-volume compensatory reserve derived from ICP and arterial blood pressure (ABP) waveforms. METHOD 96 patients with intracranial hypertension were studied retrospectively: 57 with fatal outcome and 39 with favourable outcome. ABP and ICP waveforms were recorded. Indices of cerebrovascular reactivity (PRx) and cerebrospinal compensatory reserve (RAP) were calculated as moving correlation coefficients between slow waves of ABP and ICP, and between slow waves of ICP pulse amplitude and mean ICP, respectively. The magnitude of 'slow waves' was derived using ICP low-pass spectral filtration. RESULTS The most significant difference was found in the magnitude of slow waves that was persistently higher in patients with a favourable outcome (p<0.00004). In patients who died ICP was significantly higher (p<0.0001) and cerebrovascular pressure-reactivity (described by PRx) was compromised (p<0.024). In the same patients, pressure-volume compensatory reserve showed a gradual deterioration over time with a sudden drop of RAP when ICP started to rise, suggesting an overlapping disruption of the vasomotor response. CONCLUSION Indices derived from ICP waveform analysis can be helpful for the interpretation of progressive intracranial hypertension in patients after brain trauma.
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Affiliation(s)
- M Balestreri
- Department of Neurosurgery, Addenbrooke's Hospital, Cambridge, UK
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Johnston AJ, Steiner LA, Chatfield DA, Coleman MR, Coles JP, Al-Rawi PG, Menon DK, Gupta AK. Effects of propofol on cerebral oxygenation and metabolism after head injury. Br J Anaesth 2004; 91:781-6. [PMID: 14633744 DOI: 10.1093/bja/aeg256] [Citation(s) in RCA: 46] [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: 11/14/2022] Open
Abstract
BACKGROUND Flow-metabolism coupling is thought to be deranged after traumatic brain injury, while the effects of propofol on flow-metabolism coupling are controversial. We have used a step increase in target plasma propofol concentration in head injured patients to explore flow-metabolism coupling in these patients. METHODS Ten patients with a moderate to severe head injury received a step increase in propofol target controlled infusion of 2 microg x ml(-1). Cerebral tissue gas measurements were recorded using a multimodal sensor, and regional chemistry was assessed using microdialysis. Arterial-jugular venous oxygen differences (AVDO(2)) were measured and all patients had cortical function monitoring (EEG). RESULTS The step increase in propofol led to a large increase in EEG burst-suppression ratio (0% (range 0-1.1) to 46.1% (range 0-61.7), P<0.05); however, this did not significantly change tissue gas levels, tissue chemistry, or AVDO(2). CONCLUSIONS Flow-metabolism coupling remains intact during a step increase in propofol after traumatic brain injury. The EEG burst-suppression induced by propofol after traumatic brain injury does not appear to be a useful therapeutic tool in reducing the level of regional ischaemic burden.
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Affiliation(s)
- A J Johnston
- University of Cambridge Department of Anaesthesia, Box 93, Cambridge CB2 2QQ, UK.
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Balestreri M, Czosnyka M, Chatfield DA, Steiner LA, Schmidt EA, Smielewski P, Matta B, Pickard JD. Predictive value of Glasgow Coma Scale after brain trauma: change in trend over the past ten years. J Neurol Neurosurg Psychiatry 2004; 75:161-2. [PMID: 14707332 PMCID: PMC1757441] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 03/16/2023]
Abstract
BACKGROUND Age and the Glasgow Coma Scale (GCS) score on admission are considered important predictors of outcome after traumatic brain injury. We investigated the predictive value of the GCS in a large group of patients whose computerised multimodal bedside monitoring data had been collected over the previous 10 years. METHODS Data from 358 subjects with head injury, collected between 1992 and 2001, were analysed retrospectively. Patients were grouped according to year of admission. Glasgow Outcome Scores (GOS) were determined at six months. Spearman's correlation coefficients between GCS and GOS scores were calculated for each year. RESULTS On average 34 (SD: 7) patients were monitored every year. We found a significant correlation between the GCS and GOS for the first five years (overall 1992-1996: r = 0.41; p<0.00001; n = 183) and consistent lack of correlations from 1997 onwards (overall 1997-2001: r = 0.091; p = 0.226; n = 175). In contrast, correlations between age and GOS were in both time periods significant and similar (r = -0.24 v r = -0.24; p<0.002). CONCLUSIONS The admission GCS lost its predictive value for outcome in this group of patients from 1997 onwards. The predictive value of the GCS should be carefully reconsidered when building prognostic models incorporating multimodality monitoring after head injury.
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Affiliation(s)
- M Balestreri
- Academic Neurosurgical Unit, Addenbrooke's Hospital, Cambridge, UK
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Steiner LA, Coles JP, Czosnyka M, Minhas PS, Fryer TD, Aigbirhio FI, Clark JC, Smielewski P, Chatfield DA, Donovan T, Pickard JD, Menon DK. Cerebrovascular pressure reactivity is related to global cerebral oxygen metabolism after head injury. J Neurol Neurosurg Psychiatry 2003; 74:765-70. [PMID: 12754348 PMCID: PMC1738479 DOI: 10.1136/jnnp.74.6.765] [Citation(s) in RCA: 59] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
Abstract
BACKGROUND After head injury, impaired cerebrovascular autoregulation has been associated with abnormally high or low cerebral blood flow. The physiological relevance of cerebral blood flow levels is difficult to assess in these patients, whose cerebral metabolic rate for oxygen (CMRO(2)) is known to be abnormal. Investigation of these relations requires quantitative measures of cerebral blood flow and CMRO(2), to allow assessment of oxygen supply and demand relations. OBJECTIVES To investigate the relation between dysautoregulation and global cerebral oxygen metabolism following head injury. METHODS Using positron emission tomography, global cerebral blood flow, CMRO(2), and oxygen extraction fraction were determined in 22 patients who were investigated in 26 examinations on days 1 to 11 (mean (SD), 3.5 (2.3)) after head injury. Cerebrovascular pressure reactivity was assessed using a pressure reactivity index, calculated as the moving linear correlation coefficient between mean arterial blood pressure and intracranial pressure. Outcome was assessed six months after injury using the Glasgow outcome scale. RESULTS Low CMRO(2) was associated with disturbed pressure reactivity (inverse function, R(2) = 0.21, p = 0.018) and there was a correlation between disturbed pressure reactivity and oxygen extraction fraction (quadratic function, R(2) = 0.55, p = 0.0001). There was no significant relation between pressure reactivity and cerebral blood flow. An unfavourable outcome was associated with disturbed pressure reactivity. There was no significant relation between outcome and CMRO(2) or oxygen extraction fraction. CONCLUSIONS There is a close relation between dysautoregulation and abnormal cerebral metabolism but not blood flow. Further studies are needed to determine whether metabolic dysfunction is a result of or a cause of disturbed pressure reactivity, and to establish if there is a relation between cerebral oxygen metabolism and outcome.
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Affiliation(s)
- L A Steiner
- Wolfson Brain Imaging Centre, University of Cambridge, Addenbrooke's Hospital, Cambridge, UK.
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Abstract
There has long been an appreciation that cerebral blood flow is modulated to ensure adequate cerebral oxygen delivery in the face of systemic hypoxaemia. There is increasing appreciation of the modulatory role of hyperoxia in the cerebral circulation and a consideration of the effects of such modulation on the maintenance of cerebral tissue oxygen concentration. These newer findings are particularly important in view of the fact that cerebrovascular and tissue oxygen responses to hyperoxia may change in disease. Such alterations provide important insights into pathophysiological mechanisms and may provide novel targets for therapy. However, before the modulatory effects of hyperoxia can be used for diagnosis, to predict prognosis or to direct therapy, a more detailed analysis and understanding of the physiological concepts behind this modulation are required, as are the limitations of the measurement tools used to define the modulation. This overview summarizes the available information in this area and suggests some avenues for further research.
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Affiliation(s)
- A J Johnston
- University of Cambridge Department of Anaesthetics, Box 93 and Academic Neurosurgery, Addenbrooke's Hospital, Cambridge CB2 2QQ, UK.
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Steiner LA, Johnston AJ, Salvador R, Czosnyka M, Menon DK. Validation of a tonometric noninvasive arterial blood pressure monitor in the intensive care setting. Anaesthesia 2003; 58:448-54. [PMID: 12694001 DOI: 10.1046/j.1365-2044.2003.03122.x] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.8] [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
Intra-arterial measurement is considered the gold standard for continuous, beat-to-beat arterial blood pressure monitoring. However, arterial cannulation can be difficult and may cause complications such as thrombosis and ischaemia. Recently, a tonometric system, the Colin CBM-7000 has been developed for noninvasive beat-to-beat measurement of arterial blood pressure from the radial artery. We assessed the level of agreement between the CBM-7000 and invasive radial artery measurements in 15 patients on a neuro-intensive care unit. Agreement of systolic, diastolic and mean arterial pressure values was limited, with approximately 34% of mean arterial pressures differing by over 10 mmHg. In many cases, this was due to a downward drift of the noninvasive measurements over time. Furthermore, there was a tendency to underestimate low pressures and overestimate high pressures. In our opinion, the Colin CBM-7000 cannot be recommended for continuous blood pressure monitoring in the intensive care setting.
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Affiliation(s)
- L A Steiner
- University Department of Anaesthesia and Academic Neurosurgery, Box 167, Addenbrooke's Hospital, Cambridge CB2 2QQ, UK.
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Abstract
BACKGROUND A reduction in the arterial partial pressure of CO2 (PaCO2) leads to a rapid reduction in cerebral blood flow (CBF). However, despite continuing hypocapnia there is secondary recovery of CBF over time as a result of increases in lactic acid production. Hyperoxia is thought to modulate the production of lactic acid. This study examined the kinetics of middle cerebral artery flow velocity (MCA FV) reduction during hyperventilation, and its modulation by hyperoxia. METHODS Cerebral blood flow was assessed using transcranial Doppler ultrasound in nine healthy, awake human volunteers. Subjects were ventilated, via a mouthpiece, to achieve a stable end-tidal CO2 (PETCO2). After a 20-min baseline period the minute volume on the ventilator was passively increased by approximately 20% to reduce PETCO2 by 0.75-1 kPa. After a 10-min stabilization period the new PETCO2 level was maintained at a constant level for 20 min, and MCA FV recovery was measured during this 20-min period. Subjects undertook the protocol breathing air and breathing 100% oxygen. RESULTS The PETCO2 level was (mean +/- SD) 4.9 +/- 0.4 kPa (normoxia baseline), 4.0 +/- 0.3 kPa (normoxia hyperventilation), 4.6 +/- 0.4 kPa (hyperoxia baseline) and 3.9 +/- 0.4 kPa (hyperoxia hyperventilation). CO2 reactivity was significantly lower with normoxia than hyperoxia (16.5 +/- 3.8 vs. 21.2 +/- 4.6 % kPa-1; P< 0.05). Middle cerebral artery FV recovery was significantly more rapid with normoxia than hyperoxia (0.23 +/- 0.17 vs. 0.08 +/- 0.1 % baseline min-1; P< 0.01). CONCLUSIONS Our results suggest that cerebral hemodynamic responses to moderate hyperventilation are different in normoxic and hyperoxic conditions. Clinical assessment of CO2 reactivity and CBF recovery during hyperventilation should take the degree of arterial oxygenation into account.
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Affiliation(s)
- A J Johnston
- Department of Anaesthetics, Addenbrooke's Hospital, University of Cambridge, Academic Neurosurgery, Addenbrooke's Hospital, Cambridge, UK.
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48
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Steiner LA, Czosnyka M. Estimation of critical closing pressure and cerebral perfusion pressure using transcranial Doppler. Br J Anaesth 2003; 90:396-7; author reply 396-7. [PMID: 12594160 DOI: 10.1093/bja/aeg532] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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Coles JP, Steiner LA, Martin J, Donovan T, Hutchinson PJ, Carpenter TA, Menon DK. Assessment of the Ventrix parenchymal intracranial pressure monitoring probe (NL950-P) and Monitor (NL950-100) in a 3 Tesla magnetic resonance scanner. Anaesthesia 2003; 58:143-8. [PMID: 12562410 DOI: 10.1046/j.1365-2044.2003.02966.x] [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: 01/07/2023]
Abstract
Magnetic resonance (MR) imaging and spectroscopy provide important information in patients with acute head injury. However, optimal patient management requires intracranial pressure (ICP) monitoring. There are few reports on the use of ICP sensors in an MR environment. We tested the Ventrix parenchymal intracranial pressure monitoring probe and monitor (Integra Neurosciences, USA), modified by the use of a fibre-optic extension cable, within a 3 Tesla MR system. The device performed well in the MR environment, but one element within the fibre-optic extension was significantly ferromagnetic. The ICP probe produced a small susceptibility artefact on spin echo images, and a larger artefact on gradient echo images. The MR safety of the integrated system is probably acceptable, but could be easily improved with minor modifications. Although the system is MR compatible and produces generally acceptable imaging even at 3 Tesla, there is significant degradation of image quality during gradient echo sequences.
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Affiliation(s)
- J P Coles
- Department of Anaesthesia and Wolfson Brain Imaging Centre, Box 93, Addenbrookes Hospital, University of Cambridge, CB2 2QQ, UK
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Steiner LA, Balestreri M, Johnston AJ, Czosnyka M, Coles JP, Pickard JD, Menon DK. Hyperventilation-induced reductions in cerebral blood flow velocity outlive the reduction in intracranial pressure in head-injured patients. Crit Care 2003; 7. [PMCID: PMC3301519 DOI: 10.1186/cc1963] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
Affiliation(s)
- LA Steiner
- Academic Neurosurgery, Addenbrooke's Hospital, Cambridge, UK,Department of Anaesthesia, Addenbrooke's Hospital, Cambridge, UK
| | - M Balestreri
- Academic Neurosurgery, Addenbrooke's Hospital, Cambridge, UK
| | - AJ Johnston
- Department of Anaesthesia, Addenbrooke's Hospital, Cambridge, UK
| | - M Czosnyka
- Academic Neurosurgery, Addenbrooke's Hospital, Cambridge, UK
| | - JP Coles
- Department of Anaesthesia, Addenbrooke's Hospital, Cambridge, UK
| | - JD Pickard
- Academic Neurosurgery, Addenbrooke's Hospital, Cambridge, UK
| | - DK Menon
- Department of Anaesthesia, Addenbrooke's Hospital, Cambridge, UK
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