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Wulff H, Christophersen P, Colussi P, Chandy KG, Yarov-Yarovoy V. Antibodies and venom peptides: new modalities for ion channels. Nat Rev Drug Discov 2019; 18:339-357. [PMID: 30728472 PMCID: PMC6499689 DOI: 10.1038/s41573-019-0013-8] [Citation(s) in RCA: 105] [Impact Index Per Article: 21.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
Abstract
Ion channels play fundamental roles in both excitable and non-excitable tissues and therefore constitute attractive drug targets for myriad neurological, cardiovascular and metabolic diseases as well as for cancer and immunomodulation. However, achieving selectivity for specific ion channel subtypes with small-molecule drugs has been challenging, and there currently is a growing trend to target ion channels with biologics. One approach is to improve the pharmacokinetics of existing or novel venom-derived peptides. In parallel, after initial studies with polyclonal antibodies demonstrated the technical feasibility of inhibiting channel function with antibodies, multiple preclinical programmes are now using the full spectrum of available technologies to generate conventional monoclonal and engineered antibodies or nanobodies against extracellular loops of ion channels. After a summary of the current state of ion channel drug discovery, this Review discusses recent developments using the purinergic receptor channel P2X purinoceptor 7 (P2X7), the voltage-gated potassium channel KV1.3 and the voltage-gated sodium channel NaV1.7 as examples of targeting ion channels with biologics.
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Affiliation(s)
- Heike Wulff
- Department of Pharmacology, University of California Davis, Davis, CA, USA.
| | | | | | - K George Chandy
- Molecular Physiology Laboratory, Infection and Immunity Theme, Lee Kong Chian School of Medicine, Nanyang Technological University, Singapore, Singapore
| | - Vladimir Yarov-Yarovoy
- Department of Physiology & Membrane Biology, University of California Davis, Davis, CA, USA
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2
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Autoimmune autonomic ganglionopathy associated with monoclonal gammopathy of undetermined significance: a case report. Neurol Sci 2019; 40:1481-1483. [PMID: 30685800 DOI: 10.1007/s10072-019-3731-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2018] [Accepted: 01/17/2019] [Indexed: 10/27/2022]
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3
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Ueno T, Hasegawa Y, Hagiwara R, Kon T, Nunomura JI, Tomiyama M. Integrated treatment for autonomic paraneoplastic syndrome improves performance status in a patient with small lung cell carcinoma: a case report. BMC Neurol 2018; 18:189. [PMID: 30414621 PMCID: PMC6230283 DOI: 10.1186/s12883-018-1192-3] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/05/2018] [Accepted: 10/28/2018] [Indexed: 01/25/2023] Open
Abstract
BACKGROUND Paraneoplastic neurological syndromes (PNS) are rare disorders associated with cancer and are believed to be immune mediated. Patients with autonomic PNS suffer from variable combinations of parasympathetic and sympathetic failure. Autonomic PNS are usually associated with other PNS, such as encephalomyelitis and sensory neuropathy; however, autonomic symptoms may rarely manifest as PNS symptoms. Autonomic symptoms, therefore, may be overlooked in patients with cancer. CASE PRESENTATION We described a 65-year-old Japanese man who was diagnosed with autonomic PNS due to small-cell lung carcinoma (SCLC) with Eastern Cooperative Oncology Group (ECOG) performance status 3, who suffered from orthostatic hypotension, and urinary retention needing a urethral balloon. Laboratory studies showed decreased levels of noradrenaline, and were positive for anti-ganglionic acetylcholine receptor antibody, type 1 antineuronal nuclear antibody, and sry-like high mobility group box 1 antibody. Nerve conduction evaluations and 123I-metaiodobenzylguanidine myocardial scintigraphy showed no abnormalities. Abdominal contrast-enhanced computed tomography revealed marked colonic distention. The patient's autonomic symptoms resolved following integrated treatment (symptomatic treatment, immunotherapy, and additional chemotherapy) enabling the patient to walk, remove the urethral balloon, and endure further chemotherapy. ECOG performance status remained at 1, 10 months after admission. CONCLUSIONS Integrated treatment for autonomic PNS may improve autonomic symptoms and ECOG performance status of patients with cancer.
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Affiliation(s)
- Tatsuya Ueno
- Department of Neurology, Aomori Prefectural Central Hospital, 2-1-1 Higashi-Tsukurimichi, Aomori, 030-8551, Japan.
| | - Yukihiro Hasegawa
- Department of Respiratory Medicine, Aomori Prefectural Central Hospital, 2-1-1 Higashi-Tsukurimichi, Aomori, 030-8551, Japan
| | - Rie Hagiwara
- Department of Neurology, Aomori Prefectural Central Hospital, 2-1-1 Higashi-Tsukurimichi, Aomori, 030-8551, Japan
| | - Tomoya Kon
- Department of Neurology, Aomori Prefectural Central Hospital, 2-1-1 Higashi-Tsukurimichi, Aomori, 030-8551, Japan
| | - Jin-Ichi Nunomura
- Department of Neurology, Aomori Prefectural Central Hospital, 2-1-1 Higashi-Tsukurimichi, Aomori, 030-8551, Japan
| | - Masahiko Tomiyama
- Department of Neurology, Aomori Prefectural Central Hospital, 2-1-1 Higashi-Tsukurimichi, Aomori, 030-8551, Japan
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Singh J, Santosh P. Key issues in Rett syndrome: emotional, behavioural and autonomic dysregulation (EBAD) - a target for clinical trials. Orphanet J Rare Dis 2018; 13:128. [PMID: 30064458 PMCID: PMC6069816 DOI: 10.1186/s13023-018-0873-8] [Citation(s) in RCA: 20] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2017] [Accepted: 07/10/2018] [Indexed: 02/02/2023] Open
Abstract
Complex neurodevelopmental disorders need multi-disciplinary treatment approaches for optimal care. The clinical effectiveness of treatments is limited in patients with rare genetic syndromes with multisystem morbidity. Emotional and behavioural dysregulation is common across many neurodevelopmental disorders. It can manifest in children across multiple diagnostic groups, including those on the autism spectrum and in rare genetic syndromes such as Rett Syndrome (RTT). There is, however a remarkable scarcity in the literature on the impact of the autonomic component on emotional and behavioural regulation in these disorders, and on the longer-term outcomes on disorder burden.RTT is a debilitating and often life-threatening disorder involving multiple overlapping physiological systems. Autonomic dysregulation otherwise known as dysautonomia is a cardinal feature of RTT characterised by an imbalance between the sympathetic and parasympathetic arms of the autonomic nervous system. Unlocking the autonomic component of emotional and behavioural dysregulation would be central in reducing the impairment seen in patients with RTT. In this vein, Emotional, Behavioural and Autonomic Dysregulation (EBAD) would be a useful construct to target for treatment which could mitigate burden and improve the quality of life of patients.RTT can be considered as a congenital dysautonomia and because EBAD can give rise to impairments occurring in multiple overlapping physiological systems, understanding these physiological responses arising out of EBAD would be a critical part to consider when planning treatment strategies and improving clinical outcomes in these patients. Biometric guided pharmacological and bio-feedback therapy for the behavioural and emotional aspects of the disorder offers an attracting perspective to manage EBAD in these patients. This can also allow for the stratification of patients into clinical trials and could ultimately help streamline the patient care pathway for optimal outcomes.The objectives of this review are to emphasise the key issues relating to the management of EBAD in patients with RTT, appraise clinical trials done in RTT from the perspective of autonomic physiology and to discuss the potential of EBAD as a target for clinical trials.
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Affiliation(s)
- Jatinder Singh
- Department of Child and Adolescent Psychiatry, Institute of Psychiatry, Psychology and Neuroscience, King's College London, London, UK
| | - Paramala Santosh
- Department of Child and Adolescent Psychiatry, Institute of Psychiatry, Psychology and Neuroscience, King's College London, London, UK. .,Centre for Interventional Paediatric Psychopharmacology and Rare Diseases, South London and Maudsley NHS Foundation Trust, London, UK.
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Vaeth M, Feske S. Ion channelopathies of the immune system. Curr Opin Immunol 2018; 52:39-50. [PMID: 29635109 PMCID: PMC6004246 DOI: 10.1016/j.coi.2018.03.021] [Citation(s) in RCA: 67] [Impact Index Per Article: 11.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2018] [Revised: 03/18/2018] [Accepted: 03/20/2018] [Indexed: 01/25/2023]
Abstract
Ion channels and transporters move ions across membrane barriers and are essential for a host of cell functions in many organs. They conduct K+, Na+ and Cl-, which are essential for regulating the membrane potential, H+ to control intracellular and extracellular pH and divalent cations such as Ca2+, Mg2+ and Zn2+, which function as second messengers and cofactors for many proteins. Inherited channelopathies due to mutations in ion channels or their accessory proteins cause a variety of diseases in the nervous, cardiovascular and other tissues, but channelopathies that affect immune function are not as well studied. Mutations in ORAI1 and STIM1 genes that encode the Ca2+ release-activated Ca2+ (CRAC) channel in immune cells, the Mg2+ transporter MAGT1 and the Cl- channel LRRC8A all cause immunodeficiency with increased susceptibility to infection. Mutations in the Zn2+ transporters SLC39A4 (ZIP4) and SLC30A2 (ZnT2) result in nutritional Zn2+ deficiency and immune dysfunction. These channels, however, only represent a fraction of ion channels that regulate immunity as demonstrated by immune dysregulation in channel knockout mice. The immune system itself can cause acquired channelopathies that are associated with a variety of diseases of nervous, cardiovascular and endocrine systems resulting from autoantibodies binding to ion channels. These autoantibodies highlight the therapeutic potential of functional anti-ion channel antibodies that are being developed for the treatment of autoimmune, inflammatory and other diseases.
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Affiliation(s)
- Martin Vaeth
- Department of Pathology, New York University School of Medicine, New York, NY 10016, USA
| | - Stefan Feske
- Department of Pathology, New York University School of Medicine, New York, NY 10016, USA.
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Schwartz J, Padmanabhan A, Aqui N, Balogun RA, Connelly-Smith L, Delaney M, Dunbar NM, Witt V, Wu Y, Shaz BH. Guidelines on the Use of Therapeutic Apheresis in Clinical Practice-Evidence-Based Approach from the Writing Committee of the American Society for Apheresis: The Seventh Special Issue. J Clin Apher 2017; 31:149-62. [PMID: 27322218 DOI: 10.1002/jca.21470] [Citation(s) in RCA: 276] [Impact Index Per Article: 39.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
The American Society for Apheresis (ASFA) Journal of Clinical Apheresis (JCA) Special Issue Writing Committee is charged with reviewing, updating, and categorizing indications for the evidence-based use of therapeutic apheresis in human disease. Since the 2007 JCA Special Issue (Fourth Edition), the Committee has incorporated systematic review and evidence-based approaches in the grading and categorization of apheresis indications. This Seventh Edition of the JCA Special Issue continues to maintain this methodology and rigor to make recommendations on the use of apheresis in a wide variety of diseases/conditions. The JCA Seventh Edition, like its predecessor, has consistently applied the category and grading system definitions in the fact sheets. The general layout and concept of a fact sheet that was used since the fourth edition has largely been maintained in this edition. Each fact sheet succinctly summarizes the evidence for the use of therapeutic apheresis in a specific disease entity. The Seventh Edition discusses 87 fact sheets (14 new fact sheets since the Sixth Edition) for therapeutic apheresis diseases and medical conditions, with 179 indications, which are separately graded and categorized within the listed fact sheets. Several diseases that are Category IV which have been described in detail in previous editions and do not have significant new evidence since the last publication are summarized in a separate table. The Seventh Edition of the JCA Special Issue serves as a key resource that guides the utilization of therapeutic apheresis in the treatment of human disease. J. Clin. Apheresis 31:149-162, 2016. © 2016 Wiley Periodicals, Inc.
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Affiliation(s)
- Joseph Schwartz
- Department of Pathology and Cell Biology, Columbia University Medical Center, New York, New York
| | - Anand Padmanabhan
- Blood Center of Wisconsin, Department of Pathology, Medical College of Wisconsin, Milwaukee, Wisconsin
| | - Nicole Aqui
- Department of Pathology and Laboratory Medicine, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania
| | - Rasheed A Balogun
- Division of Nephrology, University of Virginia, Charlottesville, Virginia
| | - Laura Connelly-Smith
- Department of Medicine, Seattle Cancer Care Alliance and University of Washington, Seattle, Washington
| | - Meghan Delaney
- Bloodworks Northwest, Department of Laboratory Medicine, University of Washington, Seattle, Washington
| | - Nancy M Dunbar
- Department of Pathology and Laboratory Medicine, Dartmouth-Hitchcock Medical Center, Lebanon, New Hampshire
| | - Volker Witt
- Department for Pediatrics, St. Anna Kinderspital, Medical University of Vienna, Vienna, Austria
| | - Yanyun Wu
- Bloodworks Northwest, Department of Laboratory Medicine, Yale University School of Medicine, New Haven, Connecticut
| | - Beth H Shaz
- Department of Pathology and Cell Biology, Columbia University Medical Center, New York, New York.,New York Blood Center, Department of Pathology.,Department of Pathology and Laboratory Medicine, Emory University School of Medicine, Atlanta, Georgia
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7
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Acute Disseminated Encephalomyelitis. J Clin Apher 2016; 31:163-202. [PMID: 27322219 DOI: 10.1002/jca.21474] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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8
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Bargerstock E, Puvenna V, Iffland P, Falcone T, Hossain M, Vetter S, Man S, Dickstein L, Marchi N, Ghosh C, Carvalho-Tavares J, Janigro D. Is peripheral immunity regulated by blood-brain barrier permeability changes? PLoS One 2014; 9:e101477. [PMID: 24988410 PMCID: PMC4079719 DOI: 10.1371/journal.pone.0101477] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2013] [Accepted: 06/06/2014] [Indexed: 12/19/2022] Open
Abstract
S100B is a reporter of blood-brain barrier (BBB) integrity which appears in blood when the BBB is breached. Circulating S100B derives from either extracranial sources or release into circulation by normal fluctuations in BBB integrity or pathologic BBB disruption (BBBD). Elevated S100B matches the clinical presence of indices of BBBD (gadolinium enhancement or albumin coefficient). After repeated sub-concussive episodes, serum S100B triggers an antigen-driven production of anti-S100B autoantibodies. We tested the hypothesis that the presence of S100B in extracranial tissue is due to peripheral cellular uptake of serum S100B by antigen presenting cells, which may induce the production of auto antibodies against S100B. To test this hypothesis, we used animal models of seizures, enrolled patients undergoing repeated BBBD, and collected serum samples from epileptic patients. We employed a broad array of techniques, including immunohistochemistry, RNA analysis, tracer injection and serum analysis. mRNA for S100B was segregated to barrier organs (testis, kidney and brain) but S100B protein was detected in immunocompetent cells in spleen, thymus and lymph nodes, in resident immune cells (Langerhans, satellite cells in heart muscle, etc.) and BBB endothelium. Uptake of labeled S100B by rat spleen CD4+ or CD8+ and CD86+ dendritic cells was exacerbated by pilocarpine-induced status epilepticus which is accompanied by BBBD. Clinical seizures were preceded by a surge of serum S100B. In patients undergoing repeated therapeutic BBBD, an autoimmune response against S100B was measured. In addition to its role in the central nervous system and its diagnostic value as a BBBD reporter, S100B may integrate blood-brain barrier disruption to the control of systemic immunity by a mechanism involving the activation of immune cells. We propose a scenario where extravasated S100B may trigger a pathologic autoimmune reaction linking systemic and CNS immune responses.
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Affiliation(s)
- Erin Bargerstock
- Cerebrovascular Research, Cleveland Clinic Lerner College of Medicine, Cleveland, Ohio, United States of America
| | - Vikram Puvenna
- Cerebrovascular Research, Cleveland Clinic Lerner College of Medicine, Cleveland, Ohio, United States of America
- Department of Neurosurgery, Cleveland Clinic Lerner College of Medicine, Cleveland, Ohio, United States of America
- Department of Biomedical Engineering, Cleveland Clinic Lerner College of Medicine, Cleveland, Ohio, United States of America
| | - Philip Iffland
- Cerebrovascular Research, Cleveland Clinic Lerner College of Medicine, Cleveland, Ohio, United States of America
- Kent State University, Kent, Ohio, United States of America
| | - Tatiana Falcone
- Cerebrovascular Research, Cleveland Clinic Lerner College of Medicine, Cleveland, Ohio, United States of America
- Department of Psychiatry, Cleveland Clinic Lerner College of Medicine, Cleveland, Ohio, United States of America
| | - Mohammad Hossain
- Cerebrovascular Research, Cleveland Clinic Lerner College of Medicine, Cleveland, Ohio, United States of America
- Department of Neurosurgery, Cleveland Clinic Lerner College of Medicine, Cleveland, Ohio, United States of America
- Department of Biomedical Engineering, Cleveland Clinic Lerner College of Medicine, Cleveland, Ohio, United States of America
| | - Stephen Vetter
- Cerebrovascular Research, Cleveland Clinic Lerner College of Medicine, Cleveland, Ohio, United States of America
| | - Shumei Man
- Cerebrovascular Research, Cleveland Clinic Lerner College of Medicine, Cleveland, Ohio, United States of America
| | - Leah Dickstein
- Cerebrovascular Research, Cleveland Clinic Lerner College of Medicine, Cleveland, Ohio, United States of America
| | - Nicola Marchi
- Cerebrovascular Research, Cleveland Clinic Lerner College of Medicine, Cleveland, Ohio, United States of America
| | - Chaitali Ghosh
- Cerebrovascular Research, Cleveland Clinic Lerner College of Medicine, Cleveland, Ohio, United States of America
- Department of Neurosurgery, Cleveland Clinic Lerner College of Medicine, Cleveland, Ohio, United States of America
- Department of Biomedical Engineering, Cleveland Clinic Lerner College of Medicine, Cleveland, Ohio, United States of America
| | - Juliana Carvalho-Tavares
- Cerebrovascular Research, Cleveland Clinic Lerner College of Medicine, Cleveland, Ohio, United States of America
| | - Damir Janigro
- Cerebrovascular Research, Cleveland Clinic Lerner College of Medicine, Cleveland, Ohio, United States of America
- Department of Neurosurgery, Cleveland Clinic Lerner College of Medicine, Cleveland, Ohio, United States of America
- Department of Biomedical Engineering, Cleveland Clinic Lerner College of Medicine, Cleveland, Ohio, United States of America
- Flocel, Inc. Cleveland, Ohio, United States of America
- * E-mail:
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9
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Abstract
Na x, which is preferentially expressed in the glial cells of sensory circumventricular organs in the brain, is a sodium channel that is poorly homologous to voltage-gated sodium channels. We previously reported that Na x is a sodium concentration ([Na+])-sensitive, but not a voltage-sensitive channel that is critically involved in body-fluid homeostasis. Nax-knockout mice do not stop ingesting salt even when dehydrated and transiently develop hypernatremia. [Na+] in body fluids is strictly controlled at 135 to 145 mM in mammals. Although the set point must be within this range, Na x was shown to have a threshold value of ~150 mM for extracellular [Na+] ([Na+]o) for activation in vitro. Therefore, the [Na+]o dependency of Na x in vivo is presumably modified by an as yet unidentified mechanism. We recently demonstrated that the [Na+]o dependency of Na x in the subfornical organ was adjusted to the physiological range by endothelin-3. Pharmacological experiments revealed that endothelin receptor B signaling was involved in this modulation of Na x gating through protein kinase C and ERK1/2 activation. In addition, we identified a case of essential hypernatremia caused by autoimmunity to Na x. Occurrence of a ganglioneuroma composed of Schwann-like cells that robustly expressed Na x was likely to induce the autoimmune response in this patient. An intravenous injection of the immunoglobulin fraction of the patient’s serum, which contained anti-Na x antibodies, into mice reproduced the patient’s symptoms. This review provides an overview of the physiological functions of Na x by summarizing our recent studies.
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Affiliation(s)
- Masaharu Noda
- Division of Molecular Neurobiology, National Institute for Basic Biology, Okazaki, Japan
- School of Life Science, The Graduate University for Advanced Studies, Okazaki, Japan
| | - Takeshi Y. Hiyama
- Division of Molecular Neurobiology, National Institute for Basic Biology, Okazaki, Japan
- School of Life Science, The Graduate University for Advanced Studies, Okazaki, Japan
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Benarroch EE. The clinical approach to autonomic failure in neurological disorders. Nat Rev Neurol 2014; 10:396-407. [DOI: 10.1038/nrneurol.2014.88] [Citation(s) in RCA: 40] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
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Schroeder C, Jordan J, Kaufmann H. Management of neurogenic orthostatic hypotension in patients with autonomic failure. Drugs 2014; 73:1267-79. [PMID: 23857549 DOI: 10.1007/s40265-013-0097-0] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
The maintenance of blood pressure in the upright position requires intact autonomic cardiovascular reflexes. Diseases that affect the sympathetic innervation of the cardiovascular system result in a sustained fall in blood pressure upon standing (i.e., neurogenic orthostatic hypotension) that can impair the blood supply to the brain and other organs and cause considerable morbidity and mortality. Here we review treatment options for neurogenic orthostatic hypotension and include an algorithm for its management that emphasizes the importance of non-pharmacologic measures and provides guidance on pharmacologic treatment options.
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Affiliation(s)
- Christoph Schroeder
- Institute of Clinical Pharmacology, OE 5350, Hannover Medical School, Carl-Neuberg-Strasse 1, 30625, Germany.
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Ost DE, Jim Yeung SC, Tanoue LT, Gould MK. Clinical and organizational factors in the initial evaluation of patients with lung cancer: Diagnosis and management of lung cancer, 3rd ed: American College of Chest Physicians evidence-based clinical practice guidelines. Chest 2013; 143:e121S-e141S. [PMID: 23649435 PMCID: PMC4694609 DOI: 10.1378/chest.12-2352] [Citation(s) in RCA: 110] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2012] [Accepted: 11/30/2012] [Indexed: 12/17/2022] Open
Abstract
BACKGROUND This guideline is intended to provide an evidence-based approach to the initial evaluation of patients with known or suspected lung cancer. It also includes an assessment of the impact of timeliness of care and multidisciplinary teams on outcome. METHODS The applicable current medical literature was identified by a computerized search and evaluated using standardized methods. Recommendations were framed using the approach described by the Guidelines Oversight Committee of the American College of Chest Physicians. Data sources included MEDLINE and the Cochrane Database of Systematic Reviews. RESULTS Initial evaluation should include a thorough history and physical examination; CT imaging; pulmonary function tests; and hemoglobin, electrolyte, liver function, and calcium levels. Additional testing for distant metastases and paraneoplastic syndromes should be determined on the basis of these results. Paraneoplastic syndromes may have an adverse impact on cancer treatment, so they should be controlled rapidly with the goal of proceeding with definitive cancer treatment in a timely manner. Although the relationship between timeliness of care and survival is difficult to quantify, efforts to deliver timely care are reasonable and should be balanced with the need to attend to other dimensions of health-care quality (eg, safety, effectiveness, efficiency, equality, consistency with patient values and preferences). Quality care will require multiple disciplines. Although it is difficult to assess the impact, we suggest that a multidisciplinary team approach to care be used, particularly for patients requiring multimodality therapy. CONCLUSIONS The initial evaluation of patients with lung cancer should include a thorough history and physical examination, pulmonary function tests, CT imaging, basic laboratory tests, and selective testing for distant metastases and paraneoplastic syndromes.
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Affiliation(s)
- David E Ost
- Department of Pulmonary Medicine, MD Anderson Cancer Center, The University of Texas, Houston, TX.
| | - Sai-Ching Jim Yeung
- Department of Emergency Medicine, MD Anderson Cancer Center, The University of Texas, Houston, TX; Department of Endocrine, Neoplasia & Hormonal Disorders, MD Anderson Cancer Center, The University of Texas, Houston, TX
| | - Lynn T Tanoue
- Department of Medicine, Section of Pulmonary and Critical Care Medicine, Yale University, New Haven, CT
| | - Michael K Gould
- Department of Research and Evaluation, Kaiser Permanente Southern California, Pasadena, CA
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13
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Sun H, Li M. Antibody therapeutics targeting ion channels: are we there yet? Acta Pharmacol Sin 2013; 34:199-204. [PMID: 23381110 DOI: 10.1038/aps.2012.202] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023] Open
Abstract
The combination of technological advances, genomic sequences and market success is catalyzing rapid development of antibody-based therapeutics. Cell surface receptors and ion channel proteins are well known drug targets, but the latter has seen less success. The availability of crystal structures, better understanding of gating biophysics and validation of physiological roles now form an excellent foundation to pursue antibody-based therapeutics targeting ion channels to treat a variety of diseases.
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14
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Benseler S, Pohl D. Childhood central nervous system vasculitis. HANDBOOK OF CLINICAL NEUROLOGY 2013; 112:1065-78. [DOI: 10.1016/b978-0-444-52910-7.00024-6] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/04/2022]
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Gressner AM, Arndt T. A. LEXIKON DER MEDIZINISCHEN LABORATORIUMSDIAGNOSTIK 2013. [PMCID: PMC7123472 DOI: 10.1007/978-3-642-12921-6_1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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16
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Sharp L, Vernino S. Paraneoplastic neuromuscular disorders. Muscle Nerve 2012; 46:841-50. [DOI: 10.1002/mus.23502] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 06/14/2012] [Indexed: 12/19/2022]
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Abstract
Potassium (K(+)) channels are essential to neuronal signaling and survival. Here we show that these proteins are targets of reactive oxygen species in mammalian brain and that their oxidation contributes to neuropathy. Thus, the KCNB1 (Kv2.1) channel, which is abundantly expressed in cortex and hippocampus, formed oligomers upon exposure to oxidizing agents. These oligomers were ∼10-fold more abundant in the brain of old than young mice. Oxidant-induced oligomerization of wild-type KCNB1 enhanced apoptosis in neuronal cells subject to oxidative insults. Consequently, a KCNB1 variant resistant to oxidation, obtained by mutating a conserved cysteine to alanine, (C73A), was neuroprotective. The fact that oxidation of KCNB1 is toxic, argues that this mechanism may contribute to neuropathy in conditions characterized by high levels of oxidative stress, such as Alzheimer's disease (AD). Accordingly, oxidation of KCNB1 channels was exacerbated in the brain of a triple transgenic mouse model of AD (3xTg-AD). The C73A variant protected neuronal cells from apoptosis induced by incubation with β-amyloid peptide (Aβ(1-42)). In an invertebrate model (Caenorhabditis elegans) that mimics aspects of AD, a C73A-KCNB1 homolog (C113S-KVS-1) protected specific neurons from apoptotic death induced by ectopic expression of human Aβ(1-42). Together, these data underscore a novel mechanism of toxicity in neurodegenerative disease.
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Abstract
Therapy for autoimmune demyelinating disorders has evolved rapidly over the past 10 years to include traditional immunosuppressants as well as novel biologicals. Antibody-mediated neuromuscular disorders are treated with therapies that acutely modulate pathogenic antibodies or chronically inhibit the humoral immune response. In other inflammatory autoimmune disorders of the peripheral and central nervous system, corticosteroids, often combined with conventional immunosuppression, and immunomodulatory treatments are used. Because autoimmune neurologic disorders are so diverse, evidence from randomized controlled trials is limited for most of the immunotherapies used in neurology. This review provides an overview of the immunotherapies currently used for neurologic disorders.
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Affiliation(s)
- Donna Graves
- Department of Neurology and Neurotherapeutics, UT Southwestern Medical Center, 5323 Harry Hines Boulevard, Dallas, TX 75390-9036, USA
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19
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Ulusoy C, Tüzün E, Kürtüncü M, Türkoğlu R, Akman-Demir G, Eraksoy M. Comparison of the Cytokine Profiles of Patients With Neuronal-Antibody-Associated Central Nervous System Disorders. Int J Neurosci 2012; 122:284-9. [DOI: 10.3109/00207454.2011.648762] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
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20
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Thaisetthawatkul P. Paraneoplastic Neuropathies. Neuromuscul Disord 2011. [DOI: 10.1002/9781119973331.ch27] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
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21
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Abstract
PURPOSE OF REVIEW Paraneoplastic syndromes occur commonly in patients with lung cancer, especially cancers of neuroendocrine origin. The syndromes can be the first clinical manifestation of malignant disease or a harbinger of cancer recurrence. To update the knowledge that would facilitate the care of lung cancer patients with paraneoplastic syndromes, this review focuses on the epidemiology, pathogenesis, clinical features, and current management of the more common and clinically relevant syndromes. RECENT FINDINGS Certain combinations of clinical signs and symptoms (endocrine, neurologic, immunologic, dermatologic, metabolic, constitutional, and hematologic) are associated with lung carcinoma as a manifestation of the secretion of cytokines and hormones by these cells or as an associated immunologic response. These syndromes can be categorized by common causative mechanisms: hormonal syndromes, autoimmune syndromes, and other syndromes of less clear cause. Recent advances in medical technology have allowed better understanding of these syndromes and the development of novel diagnostic and therapeutic tools. SUMMARY Increased awareness of paraneoplastic syndromes associated with lung cancer should lead to the earlier recognition and diagnosis of malignancies, thereby improving the overall prognosis of patients and alleviating associated comorbidities. Despite the recent advances in recognizing and treating paraneoplastic syndromes, many questions remain to be answered.
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Titulaer MJ, Soffietti R, Dalmau J, Gilhus NE, Giometto B, Graus F, Grisold W, Honnorat J, Sillevis Smitt PAE, Tanasescu R, Vedeler CA, Voltz R, Verschuuren JJGM. Screening for tumours in paraneoplastic syndromes: report of an EFNS task force. Eur J Neurol 2010; 18:19-e3. [PMID: 20880069 DOI: 10.1111/j.1468-1331.2010.03220.x] [Citation(s) in RCA: 319] [Impact Index Per Article: 22.8] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023]
Abstract
BACKGROUND paraneoplastic neurological syndromes (PNS) almost invariably predate detection of the malignancy. Screening for tumours is important in PNS as the tumour directly affects prognosis and treatment and should be performed as soon as possible. OBJECTIVES an overview of the screening of tumours related to classical PNS is given. Small cell lung cancer, thymoma, breast cancer, ovarian carcinoma and teratoma and testicular tumours are described in relation to paraneoplastic limbic encephalitis, subacute sensory neuronopathy, subacute autonomic neuropathy, paraneoplastic cerebellar degeneration, paraneoplastic opsoclonus-myoclonus, Lambert-Eaton myasthenic syndrome (LEMS), myasthenia gravis and paraneoplastic peripheral nerve hyperexcitability. METHODS many studies with class IV evidence were available; one study reached level III evidence. No evidence-based recommendations grade A-C were possible, but good practice points were agreed by consensus. RECOMMENDATIONS the nature of antibody, and to a lesser extent the clinical syndrome, determines the risk and type of an underlying malignancy. For screening of the thoracic region, a CT-thorax is recommended, which if negative is followed by fluorodeoxyglucose-positron emission tomography (FDG-PET). Breast cancer is screened for by mammography, followed by MRI. For the pelvic region, ultrasound (US) is the investigation of first choice followed by CT. Dermatomyositis patients should have CT-thorax/abdomen, US of the pelvic region and mammography in women, US of testes in men under 50 years and colonoscopy in men and women over 50. If primary screening is negative, repeat screening after 3-6 months and screen every 6 months up till 4 years. In LEMS, screening for 2 years is sufficient. In syndromes where only a subgroup of patients have a malignancy, tumour markers have additional value to predict a probable malignancy.
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Affiliation(s)
- M J Titulaer
- Department of Neurology, Leiden University Medical Center, Leiden, Netherlands.
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Hiyama TY, Matsuda S, Fujikawa A, Matsumoto M, Watanabe E, Kajiwara H, Niimura F, Noda M. Autoimmunity to the sodium-level sensor in the brain causes essential hypernatremia. Neuron 2010; 66:508-22. [PMID: 20510856 DOI: 10.1016/j.neuron.2010.04.017] [Citation(s) in RCA: 49] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 04/01/2010] [Indexed: 01/20/2023]
Abstract
Na(x) is the sodium-level sensor of body fluids in the brain involved in sodium homeostasis. Na(x)-knockout mice do not stop ingesting salt even when dehydrated. Here we report a case with clinical features of essential hypernatremia without demonstrable hypothalamic structural lesions, who was diagnosed as a paraneoplastic neurologic disorder. The patient had autoantibodies directed against Na(x), along with a ganglioneuroma composed of Schwann-like cells robustly expressing Na(x). The removal of the tumor did not reduce the autoantibody levels or relieve the symptoms. Intravenous injection of the immunoglobulin fraction of the patient's serum into mice induced abnormalities in water/salt intake and diuresis, which led to hypernatremia. In the brains of these mice, cell death was observed along with focal deposits of complement C3 and inflammatory infiltrates in circumventricular organs where Na(x) is specifically expressed. Our findings thus provide new insights into the pathogenesis of hypernatremia relevant to the sodium-level-sensing mechanism in humans.
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Affiliation(s)
- Takeshi Y Hiyama
- Division of Molecular Neurobiology, The Graduate University for Advanced Studies, Okazaki, Aichi 444-8787, Japan
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Sakakibara R, Uchiyama T, Kuwabara S, Mori M, Ito T, Yamamoto T, Awa Y, Yamaguchi C, Yuki N, Vernino S, Kishi M, Shirai K. Prevalence and mechanism of bladder dysfunction in Guillain-Barré Syndrome. Neurourol Urodyn 2009; 28:432-7. [DOI: 10.1002/nau.20663] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
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25
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Neuromyotonia as paraneoplastic manifestation of bladder carcinoma. J Neurol Sci 2009; 280:111-2. [DOI: 10.1016/j.jns.2009.01.022] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2008] [Revised: 01/13/2009] [Accepted: 01/29/2009] [Indexed: 11/23/2022]
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Marchi N, Betto G, Fazio V, Fan Q, Ghosh C, Machado A, Janigro D. Blood-brain barrier damage and brain penetration of antiepileptic drugs: role of serum proteins and brain edema. Epilepsia 2009; 50:664-77. [PMID: 19175391 PMCID: PMC2824251 DOI: 10.1111/j.1528-1167.2008.01989.x] [Citation(s) in RCA: 64] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
PURPOSE Increased blood-brain barrier (BBB) permeability is radiologically detectable in regions affected by drug-resistant epileptogenic lesions. Brain penetration of antiepileptic drugs (AEDs) may be affected by BBB damage. We studied the effects of BBB damage on brain distribution of hydrophilic [deoxy-glucose (DOG) and sucrose] and lipophilic (phenytoin and diazepam) molecules. We tested the hypothesis that lipophilic and hydrophilic drug distribution is differentially affected by BBB damage. METHODS In vivo BBB disruption (BBBD) was performed in rats by intracarotid injection of hyperosmotic mannitol. Drugs (H3-sucrose, 3H-deoxy-glucose, 14C-phenytoin, and C14-diazepam) or unlabeled phenytoin was measured and correlated to brain water content and protein extravasation. In vitro hippocampal slices were exposed to different osmolarities; drug penetration and water content were assessed by analytic and densitometric methods, respectively. RESULTS BBBD resulted in extravasation of serum protein and radiolabeled drugs, but was associated with no significant change in brain water. Large shifts in water content in brain slices in vitro caused a small effect on drug penetration. In both cases, total drug permeability increase was greater for lipophilic than hydrophilic compounds. BBBD reduced the amount of free phenytoin in the brain. DISCUSSION After BBBD, drug binding to protein is the main controller of total brain drug accumulation. Osmotic BBBD increased serum protein extravasation and reduced free phenytoin brain levels. These results underlie the importance of brain environment and BBB integrity in determining drug distribution to the brain. If confirmed in drug-resistant models, these mechanisms could contribute to drug brain distribution in refractory epilepsies.
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Affiliation(s)
- Nicola Marchi
- Department of Neurological Surgery, Cleveland Clinic Foundation, Cleveland, Ohio, U.S.A
- Department of Cell Biology, Cleveland Clinic Foundation, Cleveland, Ohio, U.S.A
- Department of Cerebrovascular Research, Cleveland Clinic Foundation, Cleveland, Ohio, U.S.A
| | - Giulia Betto
- Department of Neurological Surgery, Cleveland Clinic Foundation, Cleveland, Ohio, U.S.A
- Department of Cell Biology, Cleveland Clinic Foundation, Cleveland, Ohio, U.S.A
- Department of Cerebrovascular Research, Cleveland Clinic Foundation, Cleveland, Ohio, U.S.A
| | - Vincent Fazio
- Department of Neurological Surgery, Cleveland Clinic Foundation, Cleveland, Ohio, U.S.A
- Department of Cell Biology, Cleveland Clinic Foundation, Cleveland, Ohio, U.S.A
- Department of Cerebrovascular Research, Cleveland Clinic Foundation, Cleveland, Ohio, U.S.A
| | - Quinyuan Fan
- Department of Neurological Surgery, Cleveland Clinic Foundation, Cleveland, Ohio, U.S.A
- Department of Cell Biology, Cleveland Clinic Foundation, Cleveland, Ohio, U.S.A
- Department of Cerebrovascular Research, Cleveland Clinic Foundation, Cleveland, Ohio, U.S.A
| | - Chaitali Ghosh
- Department of Neurological Surgery, Cleveland Clinic Foundation, Cleveland, Ohio, U.S.A
- Department of Cell Biology, Cleveland Clinic Foundation, Cleveland, Ohio, U.S.A
- Department of Cerebrovascular Research, Cleveland Clinic Foundation, Cleveland, Ohio, U.S.A
| | - Andre Machado
- Center for Restorative Neuroscience, Cleveland Clinic Foundation, Cleveland, Ohio, U.S.A
| | - Damir Janigro
- Department of Neurological Surgery, Cleveland Clinic Foundation, Cleveland, Ohio, U.S.A
- Department of Cell Biology, Cleveland Clinic Foundation, Cleveland, Ohio, U.S.A
- Department of Cerebrovascular Research, Cleveland Clinic Foundation, Cleveland, Ohio, U.S.A
- Department of Molecular Medicine, Cleveland Clinic Foundation, Cleveland, Ohio, U.S.A
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Abstract
With people having the luxury of living longer there is an increasing epidemic of dementia throughout the world. It is important to distinguish true dementia from the not-unexpected loss of mental acuity as people age. This latter process has been termed "benign forgetfulness of senescence." We are all probably susceptible to memory loss if we live long enough. Progressive cognitive impairment to a clinically significant degree, with no obvious identifiable factor, such as a metabolic disturbance, drug intoxication, or medication effect, probably indicates a dementing illness, however.
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Affiliation(s)
- Roger E Kelley
- Department of Neurology, LSU Health Sciences Center, Shreveport, LA 71103, USA.
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28
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Affiliation(s)
- David S Goldstein
- Clinical Neurocardiology Section, Clinical Neurosciences Program, Division of Intramural Research, National Institute of Neurological Disorders and Stroke, NIH, Bethesda, MD 20892-1620, USA.
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Ichikawa K, Kikuchi M, Takeshita S, Nezu A. A case of chronic recurrent cerebellar ataxia responding to steroid therapy. Brain Dev 2009; 31:83-5. [PMID: 18554833 DOI: 10.1016/j.braindev.2008.04.010] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/22/2008] [Revised: 04/18/2008] [Accepted: 04/29/2008] [Indexed: 11/24/2022]
Abstract
We present a 25-month-old female having unusual cerebellar ataxia responsive to steroid therapy. She had suddenly suffered from action tremor and trunkal ataxia, following antecedent mild respiratory infection. These symptoms lasted for a month, and therefore she was referred to our hospital. No abnormal findings were disclosed for cerebrospinal fluid or MR images, but anti-glutamate receptor delta2 antibodies were detected in serum. MR spectroscopy of the cerebellum revealed a decrease in the N-acethylasparate/creatine ratio, suggesting micro-neuronal damage. She had quickly responded to high-dose methylpredonisolone therapy and the effectiveness of this steroid was reproducible in the subsequent relapses of ataxia. This clinical course seemed to be unique and was characterized as chronic recurrent cerebellar ataxia responding to steroid therapy.
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Affiliation(s)
- Kazushi Ichikawa
- Department of Pediatrics, Yokohama City University Medical Center, 4-57 Urafune-cho, Minami-ku, Yokohama 232-0024, Japan.
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Ramos A, Ballenilla F, Martin P. Uncommon epiloptogenic lesions affecting the temporal lobe. Semin Ultrasound CT MR 2008; 29:47-59. [PMID: 18383907 DOI: 10.1053/j.sult.2007.11.003] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
There are several processes implicated as uncommon causes of temporal lobe epilepsy. Trauma is the leading cause of epilepsy in young adults, intracerebral blood collection being the most consistent risk factor of seizures, especially subdural hematomas and brain contusions. Infarction is the entity most commonly related to epilepsy in the elderly population. Seizures usually present as complex seizures with high recurrence between 6 months and 2 years after stroke. There are some radiological characteristics of the affectation associated with high risk of early and late seizures. Noninfectious limbic encephalitis is a syndrome characterized by seizures, memory loss, and confusion. It includes paraneoplasic and non-paraneoplasic limbic encephalitis, both presenting as hyperintense lesion affecting temporobasal regions more evident with fluid-attenuated inversion recovery sequences. Paraneoplasic limbic encephalitis is associated with several types of tumor-induced autoimmunity against the nervous system. The tumors most frequently implicated are the lungs, testis, and breast, including Hodgkin's lymphoma, teratoma, and thymoma in young patients. Once a tumor is excluded, non-paraneoplasic limbic encephalitis has to be considered by investigating the presence of antibodies against voltage-gated potassium channels. It is associated with hyponatremia and responds to regimens of steroids, plasma exchange, and intravenous immunoglobulins. Finally, herpetic limbic encephalitis is also associated with seizures, accompanied by fever and neurologic symptoms. It presents characteristic findings and distribution on magnetic resonance imaging, which shows abnormalities in more than 90% of patients with proven Herpes simplex virus type 1.
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Affiliation(s)
- Ana Ramos
- Neuroradiology Section, Radiology Department, Hospital Doce de Octubre, Madrid, Spain.
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Camerino DC, Desaphy JF, Tricarico D, Pierno S, Liantonio A. Therapeutic Approaches to Ion Channel Diseases. ADVANCES IN GENETICS 2008; 64:81-145. [DOI: 10.1016/s0065-2660(08)00804-3] [Citation(s) in RCA: 43] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
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32
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Venance SL, Herr BE, Griggs RC. Challenges in the design and conduct of therapeutic trials in channel disorders. Neurotherapeutics 2007; 4:199-204. [PMID: 17395129 DOI: 10.1016/j.nurt.2007.01.004] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023] Open
Abstract
Neurologic channelopathies are rare, inherited paroxysmal disorders of muscle (e.g., the periodic paralyses and nondystrophic myotonias) and brain (e.g., episodic ataxias, idiopathic epilepsies, and familial hemiplegic migraine). Mutation is necessary but not sufficient for phenotypic expression and there are no simple phenotype-genotype relationships. Attacks may be spontaneous or triggered, with affected individuals often asymptomatic and neurologically normal between attacks. Performance of daily activities may be affected by the unpredictable nature; often late-onset degenerative changes cause permanent disability; for example, muscle atrophy and fixed weakness in periodic paralysis and cerebellar atrophy and progressive ataxia in the episodic ataxias. Currently, the natural history of these disorders is being defined. Clearly, the established methodologies for randomized controlled clinical trials are not feasible for rare diseases and innovative trial design is essential. There is a requirement for clinically relevant outcome measures for episodic disorders. Increasing our knowledge of the pathophysiology will help in targeting and designing rational therapeutic approaches. We will use the current understanding of the neurological channelopathies to illustrate some of the opportunities, challenges, and strategies in bringing safe and effective treatments to patients. There are reasons for optimism that new partnerships between clinical investigators, government, patient advocacy groups, and industry will prevent symptoms and progression of the neurological channelopathies.
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