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1.
Br J Sports Med ; 52(14): 894-902, 2018 Jul.
Article in English | MEDLINE | ID: mdl-29549147

ABSTRACT

One of the National Football League's (NFL) Head, Neck and Spine Committee's principal goals is to create a 'best practice' protocol for concussion diagnosis and management for its players. The science related to concussion diagnosis and management continues to evolve, thus the protocol has evolved contemporaneously. The Fifth International Conference on Concussion in Sport was held in Berlin in 2016, and guidelines for sports concussion diagnosis and management were revised and refined. The NFL Head, Neck and Spine Committee has synthesised the most recent empirical evidence for sports concussion diagnosis and management including the Berlin consensus statement and tailored it to the game played in the NFL. One of the goals of the Committee is to provide a standardised, reliable, efficient and evidence-based protocol for concussion diagnosis and management that can be applied in this professional sport during practice and game day. In this article, the end-of-season version of the 2017-18 NFL Concussion Diagnosis and Management Protocol is described along with its clinical rationale. Immediate actions for concussion programme enhancement and research are reviewed. It is the Committee's expectation that the protocol will undergo refinement and revision over time as the science and clinical practice related to concussion in sports crystallise.


Subject(s)
Athletic Injuries/diagnosis , Athletic Injuries/prevention & control , Brain Concussion/diagnosis , Brain Concussion/prevention & control , Soccer/injuries , Sports Medicine/standards , Congresses as Topic , Consensus , Humans
3.
Nat Commun ; 7: 11853, 2016 06 24.
Article in English | MEDLINE | ID: mdl-27340017

ABSTRACT

Endothelial to mesenchymal transition (EndMT) plays a major role during development, and also contributes to several adult cardiovascular diseases. Importantly, mesenchymal cells including fibroblasts are prominent in atherosclerosis, with key functions including regulation of: inflammation, matrix and collagen production, and plaque structural integrity. However, little is known about the origins of atherosclerosis-associated fibroblasts. Here we show using endothelial-specific lineage-tracking that EndMT-derived fibroblast-like cells are common in atherosclerotic lesions, with EndMT-derived cells expressing a range of fibroblast-specific markers. In vitro modelling confirms that EndMT is driven by TGF-ß signalling, oxidative stress and hypoxia; all hallmarks of atherosclerosis. 'Transitioning' cells are readily detected in human plaques co-expressing endothelial and fibroblast/mesenchymal proteins, indicative of EndMT. The extent of EndMT correlates with an unstable plaque phenotype, which appears driven by altered collagen-MMP production in EndMT-derived cells. We conclude that EndMT contributes to atherosclerotic patho-biology and is associated with complex plaques that may be related to clinical events.


Subject(s)
Atherosclerosis/pathology , Endothelial Cells/physiology , Epithelial-Mesenchymal Transition/physiology , Animals , Atherosclerosis/metabolism , Biomarkers , Cell Lineage , Cell Movement , Cell Proliferation , Humans , Mice , Oxidative Stress , Oxygen Consumption , Plaque, Atherosclerotic/metabolism , Signal Transduction , Transforming Growth Factor beta/metabolism
5.
J Clin Invest ; 124(12): 5159-74, 2014 Dec.
Article in English | MEDLINE | ID: mdl-25401476

ABSTRACT

Angioplasty and stenting is the primary treatment for flow-limiting atherosclerosis; however, this strategy is limited by pathological vascular remodeling. Using a systems approach, we identified a role for the network hub gene glutathione peroxidase-1 (GPX1) in pathological remodeling following human blood vessel stenting. Constitutive deletion of Gpx1 in atherosclerotic mice recapitulated this phenotype of increased vascular smooth muscle cell (VSMC) proliferation and plaque formation. In an independent patient cohort, gene variant pair analysis identified an interaction of GPX1 with the orphan protooncogene receptor tyrosine kinase ROS1. A meta-analysis of the only genome-wide association studies of human neointima-induced in-stent stenosis confirmed the association of the ROS1 variant with pathological remodeling. Decreased GPX1 expression in atherosclerotic mice led to reductive stress via a time-dependent increase in glutathione, corresponding to phosphorylation of the ROS1 kinase activation site Y2274. Loss of GPX1 function was associated with both oxidative and reductive stress, the latter driving ROS1 activity via s-glutathiolation of critical residues of the ROS1 tyrosine phosphatase SHP-2. ROS1 inhibition with crizotinib and deglutathiolation of SHP-2 abolished GPX1-mediated increases in VSMC proliferation while leaving endothelialization intact. Our results indicate that GPX1-dependent alterations in oxido-reductive stress promote ROS1 activation and mediate vascular remodeling.


Subject(s)
Atherosclerosis/enzymology , Muscle Proteins/metabolism , Muscle, Smooth, Vascular/enzymology , Myocytes, Smooth Muscle/enzymology , Protein-Tyrosine Kinases/metabolism , Proto-Oncogene Proteins/metabolism , Receptor Protein-Tyrosine Kinases/metabolism , Vascular Remodeling , Amino Acid Substitution , Animals , Atherosclerosis/genetics , Atherosclerosis/pathology , Cells, Cultured , Crizotinib , Female , Gene Expression Regulation, Enzymologic/drug effects , Gene Expression Regulation, Enzymologic/genetics , Glutathione Peroxidase/biosynthesis , Glutathione Peroxidase/genetics , Humans , Male , Mice , Mice, Knockout , Muscle Proteins/antagonists & inhibitors , Muscle Proteins/genetics , Muscle, Smooth, Vascular/pathology , Mutation, Missense , Myocytes, Smooth Muscle/pathology , Oxidation-Reduction , Oxidative Stress/drug effects , Oxidative Stress/genetics , Protein Kinase Inhibitors/pharmacology , Protein-Tyrosine Kinases/antagonists & inhibitors , Protein-Tyrosine Kinases/genetics , Proto-Oncogene Proteins/antagonists & inhibitors , Proto-Oncogene Proteins/genetics , Pyrazoles/pharmacology , Pyridines/pharmacology , Receptor Protein-Tyrosine Kinases/antagonists & inhibitors , Receptor Protein-Tyrosine Kinases/genetics , Glutathione Peroxidase GPX1
9.
Yale J Biol Med ; 86(3): 389-95, 2013 Sep.
Article in English | MEDLINE | ID: mdl-24058313

ABSTRACT

Dr. Elizabeth Nabel delivered the following presentation as the Lee E. Farr Lecturer on May 7, 2013, which served as the culmination of the annual Student Research Day at Yale School of Medicine. Dr. Nabel is President of the Brigham and Women's Hospital in Boston, Massachusetts, and Professor of Medicine at Harvard Medical School. Her lecture to Yale medical students portrayed her own personal and professional journey through medicine as a series of opportunities. Dr. Nabel focused on the roles and responsibilities of physicians to recognize need and to make change through focused advocacy.


Subject(s)
Schools, Medical , Humans , Students, Medical
10.
PLoS One ; 7(8): e43946, 2012.
Article in English | MEDLINE | ID: mdl-22937132

ABSTRACT

The brain-enriched protein kinase KIS (product of the gene UHMK1) has been shown to phosphorylate the human splicing factor SF1 in vitro. This phosphorylation in turn favors the formation of a U2AF(65)-SF1-RNA complex which occurs at the 3' end of introns at an early stage of spliceosome assembly. Here, we analyzed the effects of KIS knockout on mouse SF1 phosphorylation, physiology, adult behavior, and gene expression in the neonate brain. We found SF1 isoforms are differently expressed in KIS-ko mouse brains and fibroblasts. Re-expression of KIS in fibroblasts restores a wild type distribution of SF1 isoforms, confirming the link between KIS and SF1. Microarray analysis of transcripts in the neonate brain revealed a subtle down-regulation of brain specific genes including cys-loop ligand-gated ion channels and metabolic enzymes. Q-PCR analyses confirmed these defects and point to an increase of pre-mRNA over mRNA ratios, likely due to changes in splicing efficiency. While performing similarly in prepulse inhibition and most other behavioral tests, KIS-ko mice differ in spontaneous activity and contextual fear conditioning. This difference suggests that disregulation of gene expression due to KIS inactivation affects specific brain functions.


Subject(s)
Brain/metabolism , Conditioning, Psychological/physiology , Fear/physiology , Intracellular Signaling Peptides and Proteins/genetics , Protein Serine-Threonine Kinases/genetics , Animals , Behavior, Animal/physiology , Fibroblasts/metabolism , Gene Expression Regulation, Developmental , Hyperkinesis/genetics , Hyperkinesis/metabolism , Intracellular Signaling Peptides and Proteins/metabolism , Mice , Mice, Knockout , Molecular Sequence Data , Motor Activity/genetics , Phosphorylation , Protein Serine-Threonine Kinases/metabolism
12.
Trans Am Clin Climatol Assoc ; 123: 221-5; discussion 225-6, 2012.
Article in English | MEDLINE | ID: mdl-23303987

ABSTRACT

Good morning. I am delighted to join you this morning. Today I'd like to tell you an interesting translational research story whereby a rare disease can be an example for how scientific advances can lead to acceleration of new therapies. This story will include some genetic sleuthing, a creative interdisciplinary team, a foundation of protein biochemistry, cutting-edge cell biology, creation of a mouse model, designer drug development, some good luck along the way, kids enrolling in a clinical trial from around the world, and finally, unexpected consequences for a condition that affects all of us.


Subject(s)
Aging, Premature/physiopathology , Cardiovascular System/physiopathology , Progeria/physiopathology , Translational Research, Biomedical , Aging, Premature/genetics , Animals , Disease Models, Animal , Farnesyltranstransferase/antagonists & inhibitors , Humans , Lamin Type A , Mice , Mice, Transgenic , Mutation/genetics , Nuclear Proteins/genetics , Phenotype , Progeria/genetics , Protein Precursors/genetics
14.
Hum Mol Genet ; 20(23): 4748-57, 2011 Dec 01.
Article in English | MEDLINE | ID: mdl-21878436

ABSTRACT

Percutaneous coronary intervention (PCI) has become an effective therapy to treat obstructive coronary artery diseases (CAD). However, one of the major drawbacks of PCI is the occurrence of restenosis in 5-25% of all initially treated patients. Restenosis is defined as the re-narrowing of the lumen of the blood vessel, resulting in renewed symptoms and the need for repeated intervention. To identify genetic variants that are associated with restenosis, a genome-wide association study (GWAS) was conducted in 295 patients who developed restenosis (cases) and 571 who did not (controls) from the GENetic Determinants of Restenosis (GENDER) study. Analysis of ~550 000 single nucleotide polymorphisms (SNPs) in GENDER was followed by a replication phase in three independent case-control populations (533 cases and 3067 controls). A potential susceptibility locus for restenosis at chromosome 12, including rs10861032 (P(combined) = 1.11 × 10(-7)) and rs9804922 (P(combined) = 1.45 × 10(-6)), was identified in the GWAS and replication phase. In addition, both SNPs were also associated with coronary events (rs10861032, P(additive) = 0.005; rs9804922, P(additive) = 0.023) in a trial based cohort set of elderly patients with (enhanced risk of) CAD (PROSPER) and all-cause mortality in PROSPER (rs10861032, P(additive) = 0.007; rs9804922, P(additive) = 0.013) and GENDER (rs10861032, P(additive) = 0.005; rs9804922, P(additive) = 0.023). Further analysis suggests that this locus could be involved in regulatory functions.


Subject(s)
Angioplasty, Balloon, Coronary , Chromosomes, Human, Pair 12/genetics , Coronary Restenosis/genetics , Coronary Restenosis/therapy , Genetic Loci/genetics , Genetic Predisposition to Disease , Genome-Wide Association Study , Aged , Coronary Restenosis/mortality , Female , Humans , Male , Middle Aged , Polymorphism, Single Nucleotide/genetics
15.
PLoS One ; 6(9): e23975, 2011.
Article in English | MEDLINE | ID: mdl-21915271

ABSTRACT

Closure of the ductus arteriosus (DA) at birth is essential for the transition from fetal to postnatal life. Before birth the DA bypasses the uninflated lungs by shunting blood from the pulmonary trunk into the systemic circulation. The molecular mechanism underlying DA closure and degeneration has not been fully elucidated, but is associated with apoptosis and cytolytic necrosis in the inner media and intima. We detected features of histology during DA degeneration that are comparable to Hutchinson Gilford Progeria syndrome and ageing. Immunohistochemistry on human fetal and neonatal DA, and aorta showed that lamin A/C was expressed in all layers of the vessel wall. As a novel finding we report that progerin, a splicing variant of lamin A/C was expressed almost selectively in the normal closing neonatal DA, from which we hypothesized that progerin is involved in DA closure. Progerin was detected in 16.2%±7.2 cells of the DA. Progerin-expressing cells were predominantly located in intima and inner media where cytolytic necrosis accompanied by apoptosis will develop. Concomitantly we found loss of α-smooth muscle actin as well as reduced lamin A/C expression compared to the fetal and non-closing DA. In cells of the adjacent aorta, that remains patent, progerin expression was only sporadically detected in 2.5%±1.5 of the cells. Data were substantiated by the detection of mRNA of progerin in the neonatal DA but not in the aorta, by PCR and sequencing analysis. The fetal DA and the non-closing persistent DA did not present with progerin expressing cells. Our analysis revealed that the spatiotemporal expression of lamin A/C and progerin in the neonatal DA was mutually exclusive. We suggest that activation of LMNA alternative splicing is involved in vascular remodeling in the circulatory system during normal neonatal DA closure.


Subject(s)
Ductus Arteriosus/metabolism , Nuclear Proteins/metabolism , Protein Precursors/metabolism , Female , Humans , Immunohistochemistry , In Vitro Techniques , Infant, Newborn , Lamin Type A/genetics , Lamin Type A/metabolism , Nuclear Proteins/genetics , Pregnancy , Progeria/metabolism , Protein Precursors/genetics , Reverse Transcriptase Polymerase Chain Reaction , Tunica Intima/metabolism
16.
J Immunol ; 187(9): 4826-34, 2011 Nov 01.
Article in English | MEDLINE | ID: mdl-21957146

ABSTRACT

Precise control of the LPS stimulation in the lung modulates inflammation and airway hyperresponsiveness involving the well-known TLR4/NF-κB pathway. As a consequence, the expression and secretion of proinflammatory cytokines is tightly regulated with the recruitment of neutrophils. Changes in the LPS-induced responses have been observed in the Prmt2-Col6a1 monosomic model, suggesting the presence of dosage-sensitive genes controlling LPS pathway in the mouse. In this article, we report that the Prmt2 regulates the LPS-induced lung responses in lungs and macrophages. We demonstrate that Prmt2 gene dosage influences the lung airway hyperresponsiveness, the recruitment of neutrophils, and the expression of proinflammatory cytokines, such as IL-6 and TNF-α. In addition, Prmt2 loss of function also altered the nuclear accumulation of NF-κB in stimulated macrophages. Prmt2 should be considered as a new member of the NF-κB pathway controlling LPS-induced inflammatory and lung responses in a dosage-dependent manner, certainly through regulating nuclear accumulation of NF-κB as shown already in fibroblasts.


Subject(s)
Inflammation Mediators/physiology , Lipopolysaccharides/administration & dosage , Lung/immunology , Lung/metabolism , Macrophages, Alveolar/immunology , Macrophages, Alveolar/metabolism , Methyltransferases/physiology , Animals , Collagen Type VI/deficiency , Collagen Type VI/genetics , Collagen Type VI/physiology , Dose-Response Relationship, Immunologic , Genetic Carrier Screening/methods , Lipopolysaccharides/pharmacology , Lung/pathology , Macrophages, Alveolar/pathology , Methyltransferases/deficiency , Methyltransferases/genetics , Mice , Mice, Inbred C57BL , Mice, Knockout , Mice, Mutant Strains , Mice, Transgenic , NF-kappa B/genetics , NF-kappa B/physiology , Protein-Arginine N-Methyltransferases , Signal Transduction/genetics , Signal Transduction/immunology
17.
J Clin Invest ; 121(7): 2833-44, 2011 Jul.
Article in English | MEDLINE | ID: mdl-21670498

ABSTRACT

Hutchinson-Gilford progeria syndrome (HGPS), a devastating premature aging disease, is caused by a point mutation in the lamin A gene (LMNA). This mutation constitutively activates a cryptic splice donor site, resulting in a mutant lamin A protein known as progerin. Recent studies have demonstrated that progerin is also produced at low levels in normal human cells and tissues. However, the cause-and-effect relationship between normal aging and progerin production in normal individuals has not yet been determined. In this study, we have shown in normal human fibroblasts that progressive telomere damage during cellular senescence plays a causative role in activating progerin production. Progressive telomere damage was also found to lead to extensive changes in alternative splicing in multiple other genes. Interestingly, elevated progerin production was not seen during cellular senescence that does not entail telomere shortening. Taken together, our results suggest a synergistic relationship between telomere dysfunction and progerin production during the induction of cell senescence, providing mechanistic insight into how progerin may participate in the normal aging process.


Subject(s)
Cellular Senescence/physiology , Fibroblasts/physiology , Nuclear Proteins/metabolism , Protein Precursors/metabolism , Telomere/metabolism , Aging/physiology , Animals , Cells, Cultured , Fibroblasts/cytology , Humans , Lamin Type A/genetics , Lamin Type A/metabolism , Nuclear Proteins/genetics , Progeria/genetics , Progeria/physiopathology , Protein Precursors/genetics , Telomerase/genetics , Telomeric Repeat Binding Protein 2/genetics
20.
BMC Med Genomics ; 4: 20, 2011 Feb 28.
Article in English | MEDLINE | ID: mdl-21356094

ABSTRACT

BACKGROUND: The vascular disease in-stent restenosis (ISR) is characterized by formation of neointima and adverse inward remodeling of the artery after injury by coronary stent implantation. We hypothesized that the analysis of gene expression in peripheral blood mononuclear cells (PBMCs) would demonstrate differences in transcript expression between individuals who develop ISR and those who do not. METHODS AND RESULTS: We determined and investigated PBMC gene expression of 358 patients undergoing an index procedure to treat in de novo coronary artery lesions with bare metallic stents, using a novel time-varying intercept model to optimally assess the time course of gene expression across a time course of blood samples. Validation analyses were conducted in an independent sample of 97 patients with similar time-course blood sampling and gene expression data. We identified 47 probesets with differential expression, of which 36 were validated upon independent replication testing. The genes identified have varied functions, including some related to cellular growth and metabolism, such as the NAB2 and LAMP genes. CONCLUSIONS: In a study of patients undergoing bare metallic stent implantation, we have identified and replicated differential gene expression in peripheral blood mononuclear cells, studied across a time series of blood samples. The genes identified suggest alterations in cellular growth and metabolism pathways, and these results provide the basis for further specific functional hypothesis generation and testing of the mechanisms of ISR.


Subject(s)
Coronary Restenosis/genetics , Stents , Aged , Blood Cells/metabolism , Cell Adhesion Molecules, Neuronal/genetics , Cell Adhesion Molecules, Neuronal/metabolism , Coronary Restenosis/metabolism , Female , GPI-Linked Proteins/genetics , GPI-Linked Proteins/metabolism , Gene Expression Regulation , Humans , Male , Middle Aged , Repressor Proteins/genetics , Repressor Proteins/metabolism , Software , Time Factors
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