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Healy DG, Goadsby PJ, Kitchen ND, Yousry T, Hanna MG. Spontaneous intracranial hypotension, hygromata and haematomata. BMJ Case Rep 2009; 2009:bcr2007132019. [PMID: 21687310 DOI: 10.1136/bcr.2007.132019] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022] Open
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102
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103
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Matthews E, Labrum R, Sweeney MG, Sud R, Haworth A, Chinnery PF, Meola G, Schorge S, Kullmann DM, Davis MB, Hanna MG. Voltage sensor charge loss accounts for most cases of hypokalemic periodic paralysis. Neurology 2008; 72:1544-7. [PMID: 19118277 DOI: 10.1212/01.wnl.0000342387.65477.46] [Citation(s) in RCA: 127] [Impact Index Per Article: 7.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Abstract
BACKGROUND Several missense mutations of CACNA1S and SCN4A genes occur in hypokalemic periodic paralysis. These mutations affect arginine residues in the S4 voltage sensors of the channel. Approximately 20% of cases remain genetically undefined. METHODS We undertook direct automated DNA sequencing of the S4 regions of CACNA1S and SCN4A in 83 cases of hypokalemic periodic paralysis. RESULTS We identified reported CACNA1S mutations in 64 cases. In the remaining 19 cases, mutations in SCN4A or other CACNA1S S4 segments were found in 10, including three novel changes and the first mutations in channel domains I (SCN4A) and III (CACNA1S). CONCLUSIONS All mutations affected arginine residues, consistent with the gating pore cation leak hypothesis of hypokalemic periodic paralysis. Arginine mutations in S4 segments underlie 90% of hypokalemic periodic paralysis cases.
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Matthews E, Guet A, Mayer M, Vicart S, Pemble S, Sternberg D, Fontaine B, Hanna MG. Neonatal hypotonia can be a sodium channelopathy: recognition of a new phenotype. Neurology 2008; 71:1740-2. [PMID: 19015492 DOI: 10.1212/01.wnl.0000335269.21550.0e] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
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Hall AM, Unwin RJ, Hanna MG, Duchen MR. Renal function and mitochondrial cytopathy (MC): more questions than answers? QJM 2008; 101:755-66. [PMID: 18487272 DOI: 10.1093/qjmed/hcn060] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/19/2022] Open
Abstract
Our knowledge of mitochondrial biology has advanced significantly in the last 10 years. The effects of mitochondrial dysfunction or cytopathy (MC) on the heart and neuromuscular system are well known, and its involvement in the pathophysiology of several common clinical disorders such as diabetes, hyperlipidaemia and hypertension, is just beginning to emerge; however, its contribution to renal disease has received much less attention, and the available literature raises some interesting questions: Why do children with MC commonly present with a renal phenotype that is often quite different from adults? How does a mutation in mitochondrial DNA (mtDNA) lead to disease at the cellular level, and how can a single mtDNA point mutation result in such a variety of renal- and non-renal phenotypes in isolation or combined? Why are some regions of the nephron seemingly more sensitive to mitochondrial dysfunction and damage by mitochondrial toxins? Perhaps most important of all, what can be done to diagnose and treat MC, now and in the future? In this review we summarize our current understanding of the relationship between mitochondrial biology, renal physiology and clinical nephrology, in an attempt to try to answer some of these questions. Although MC is usually considered a rare defect, it is almost certainly under-diagnosed. A greater awareness and understanding of kidney involvement in MC might lead to new treatment strategies for diseases in which mitochondrial dysfunction is secondary to toxic or ischaemic injury, rather than to an underlying genetic mutation.
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106
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Healy DG, Goadsby PJ, Kitchen ND, Yousry T, Hanna MG. Neurological picture. Spontaneous intracranial hypotension, hygromata and haematomata. J Neurol Neurosurg Psychiatry 2008; 79:442. [PMID: 18344394 DOI: 10.1136/jnnp.2007.132019] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
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107
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Stewart JD, Tennant S, Powell H, Pyle A, Blakely EL, He L, Hudson G, Roberts M, du Plessis D, Gow D, Mewasingh LD, Hanna MG, Omer S, Morris AA, Roxburgh R, Livingston JH, McFarland R, Turnbull DM, Chinnery PF, Taylor RW. Novel POLG1 mutations associated with neuromuscular and liver phenotypes in adults and children. J Med Genet 2008; 46:209-14. [DOI: 10.1136/jmg.2008.058180] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
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108
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Matthews E, Tan SV, Fialho D, Sweeney MG, Sud R, Haworth A, Stanley E, Cea G, Davis MB, Hanna MG. What causes paramyotonia in the United Kingdom? Common and new SCN4A mutations revealed. Neurology 2008; 70:50-3. [PMID: 18166706 DOI: 10.1212/01.wnl.0000287069.21162.94] [Citation(s) in RCA: 48] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Abstract
OBJECTIVE To study the clinical and genetic features in a large cohort of UK patients with sodium channel paramyotonia congenita. METHODS We conducted a UK-wide clinical and molecular genetic study of patients presenting with a phenotype suggestive of paramyotonia congenita. RESULTS We identified 42 affected individuals (28 kindreds). All cases met our core criteria for a clinical diagnosis of paramyotonia congenita. Seventy-five percent of patients (32 patients/20 kindreds) had SCN4A mutations. Twenty-nine subjects from 18 kindreds had exon 22 and 24 mutations, confirming these exons to be hot spots. Unexpectedly, 3 of these subjects harbored mutations previously described with potassium-aggravated myotonia (G1306A, G1306E). We identified two new mutations (R1448L and L1436P). Ten cases (8 kindreds) without mutations exhibited paramyotonia congenita with prominent pain and weakness. CONCLUSIONS This study identifies two new mutations, confirms SCN4A as a common cause of paramyotonia congenita in the UK, and suggests further allelic and possibly genetic heterogeneity.
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Craig K, Elliott HR, Keers SM, Lambert C, Pyle A, Graves TD, Woodward C, Sweeney MG, Davis MB, Hanna MG, Chinnery PF. Episodic ataxia and hemiplegia caused by the 8993T->C mitochondrial DNA mutation. J Med Genet 2008; 44:797-9. [PMID: 18055910 DOI: 10.1136/jmg.2007.052902] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Abstract
The m.8993T-->C MTATP6 mutation of mitochondrial DNA (mtDNA) usually causes mitochondrial disease in childhood, but was recently described in a family with adult onset ataxia and polyneuropathy. Cytochrome c oxidase muscle histochemistry, which is the standard clinical investigation for mitochondrial disease in adults, is usually normal in patients with MTATP6 mutations. This raises the possibility that these cases have been missed in the past. We therefore studied 308 patients with unexplained ataxia and 96 patients with suspected Charcot-Marie-Tooth disease to determine whether the m.8993T-->C MTATP6 mutation is common in unexplained inherited ataxia and/or polyneuropathy. We identified a three-generation family with the m.8993T-->C mutation of mtDNA. One subject had episodic ataxia (EA) and transient hemipareses, broadening the phenotype. However, no further cases were identified in an additional cohort of 191 patients with suspected EA. In conclusion, m.8993T-->C MTATP6 should be considered in patients with unexplained ataxia, CMT or EA, but cases are uncommon.
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110
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Everett CM, Graves TD, Lad S, Jäger HR, Thom M, Isenberg DA, Hanna MG. Aggressive CNS lupus vasculitis in the absence of systemic disease activity. Rheumatology (Oxford) 2007; 47:107-9. [PMID: 18037608 DOI: 10.1093/rheumatology/kem264] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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111
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Jen JC, Graves TD, Hess EJ, Hanna MG, Griggs RC, Baloh RW. Primary episodic ataxias: diagnosis, pathogenesis and treatment. Brain 2007; 130:2484-93. [PMID: 17575281 DOI: 10.1093/brain/awm126] [Citation(s) in RCA: 223] [Impact Index Per Article: 13.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Primary episodic ataxias are autosomal dominant channelopathies that manifest as attacks of imbalance and incoordination. Mutations in two genes, KCNA1 and CACNA1A, cause the best characterized and account for the majority of identified cases of episodic ataxia. We summarize current knowledge of clinical and genetic diagnosis, genotype-phenotype correlations, pathophysiology and treatment of episodic ataxia syndromes. We focus on unresolved issues including phenotypic and genetic heterogeneity, lessons from animal models and technological advancement, rationale and feasibility of various treatment strategies, and shared mechanisms underlying episodic ataxia and other far more prevalent paroxysmal conditions such as epilepsy and migraine.
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112
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Abstract
Genetic association studies offer a powerful approach to identify the multiple variants of small effect that modulate susceptibility to common, complex disease. They, however, have a poor reputation, mainly because of the consistent lack of replication of all but a few. Thousands of genetic studies have been carried out on multifactorial diseases in the past 30 years, yielding only about 50 variants that can be considered to be true positives. Although the positive studies show proof of principle, the multitude of negative studies indicate fundamental problems in the design and execution of association studies. Here, we discuss some of the more pertinent study design and data analysis issues which can affect the outcome of genetic association studies.
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113
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Abstract
Granulysin expression or glucocorticoid receptor polymorphisms may be factors underlying the variable steroid response in patients with myopathies
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114
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Hudson G, Deschauer M, Taylor RW, Hanna MG, Fialho D, Schaefer AM, He LP, Blakely E, Turnbull DM, Chinnery PF. POLG1, C10ORF2, and ANT1 mutations are uncommon in sporadic progressive external ophthalmoplegia with multiple mitochondrial DNA deletions. Neurology 2006; 66:1439-41. [PMID: 16682683 DOI: 10.1212/01.wnl.0000210486.32196.24] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Abstract
The authors sequenced POLG1, C10ORF2, and ANT1 in 38 sporadic progressive external ophthalmoplegia patients with multiple mitochondrial DNA (mtDNA) deletions. Causative mutations were identified in approximately 10% of cases, with two unrelated individuals harboring a novel premature stop codon mutation (1356T>G). None had a mutation in C10ORF2 or ANT1. In the majority of patients, the primary nuclear genetic defect is likely to affect other unknown genes important for mtDNA maintenance.
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115
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Imbrici P, Eunson LH, Graves TD, Bhatia KP, Wadia NH, Kullmann DM, Hanna MG. Late-onset episodic ataxia type 2 due to an in-frame insertion in CACNA1A. Neurology 2006; 65:944-6. [PMID: 16186543 DOI: 10.1212/01.wnl.0000176069.64200.28] [Citation(s) in RCA: 46] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Abstract
Episodic ataxia type 2 (EA2) is caused by calcium channel (CACNA1A) mutations and typically begins before age 20 years. The molecular basis of late-onset EA2 is unclear. The authors describe a case of late-onset EA2 associated with the first multiple-base pair insertion in CACNA1A. Molecular expression revealed evidence of impaired calcium channel function, suggesting that genetically induced reduction in calcium channel function may associate with cases of late-onset EA2.
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116
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Hanna MG. Myology, third edition. J Neurol Psychiatry 2005. [DOI: 10.1136/jnnp.2004.059220] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
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117
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Gioltzoglou T, Cordivari C, Lee PJ, Hanna MG, Lees AJ. Problems with botulinum toxin treatment in mitochondrial cytopathy: case report and review of the literature. J Neurol Neurosurg Psychiatry 2005; 76:1594-6. [PMID: 16227561 PMCID: PMC1739393 DOI: 10.1136/jnnp.2004.057661] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
Abstract
Botulinum toxin type A (BTXA) is widely used in neurological therapeutics for a variety of indications such as dystonia, spasticity, hyperhidrosis, and hypersalivation. It is relatively contraindicated in disorders of neuromuscular transmission, in individuals with known hypersensitivity or bleeding disorders, and during pregnancy. Two patients are presented with initially undetermined multisystem neurological disorders and excessive sialorrhoea, later diagnosed as mitochondrial cytopathy, who had side effects after treatment with ultrasound guided BTXA injections. Published reports on the use of BTXA injections in hypersalivation of various causes are reviewed, along with the proposed mechanisms of hypersensitivity to BTXA in patients with mitochondrial cytopathies. Clinicians should be cautious when using BTXA injections in such patients because of the significant risk of side effects.
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118
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Davies NP, Imbrici P, Fialho D, Herd C, Bilsland LG, Weber A, Mueller R, Hilton-Jones D, Ealing J, Boothman BR, Giunti P, Parsons LM, Thomas M, Manzur AY, Jurkat-Rott K, Lehmann-Horn F, Chinnery PF, Rose M, Kullmann DM, Hanna MG. Andersen-Tawil syndrome: New potassium channel mutations and possible phenotypic variation. Neurology 2005; 65:1083-9. [PMID: 16217063 DOI: 10.1212/01.wnl.0000178888.03767.74] [Citation(s) in RCA: 64] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Abstract
OBJECTIVE To evaluate clinical, genetic, and electrophysiologic features of patients with Andersen-Tawil syndrome (ATS) in the United Kingdom. METHODS Clinical and neurophysiologic evaluation was conducted of 11 families suspected to have ATS. Molecular genetic analysis of each proband was performed by direct DNA sequencing of the entire coding region of KCNJ2. Control samples were screened by direct DNA sequencing. The electrophysiologic consequences of several new mutations were studied in an oocyte expression system. RESULTS All 11 ATS families harbored pathogenic mutations in KCNJ2 with six mutations not previously reported. Some unusual clinical features including renal tubular defect, CNS involvement, and dental and phonation abnormalities were observed. Five mutations (T75M, D78G, R82Q, L217P, and G300D) were expressed, all of which resulted in nonfunctional channels when expressed alone, and co-expression with wild-type (WT) KCNJ2 demonstrated a dominant negative effect. CONCLUSION Six new disease-causing mutations in KCNJ2 were identified, one of which was in a PIP2 binding site. Molecular expression studies indicated that five of the mutations exerted a dominant negative effect on the wild-type allele. KCNJ2 mutations are an important cause of ATS in the UK.
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119
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Venance SL, Cannon SC, Fialho D, Fontaine B, Hanna MG, Ptacek LJ, Tristani-Firouzi M, Tawil R, Griggs RC. The primary periodic paralyses: diagnosis, pathogenesis and treatment. ACTA ACUST UNITED AC 2005; 129:8-17. [PMID: 16195244 DOI: 10.1093/brain/awh639] [Citation(s) in RCA: 195] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
Periodic paralyses (PPs) are rare inherited channelopathies that manifest as abnormal, often potassium (K)-sensitive, muscle membrane excitability leading to episodic flaccid paralysis. Hypokalaemic (HypoPP) and hyperkalaemic PP and Andersen-Tawil syndrome are genetically heterogeneous. Over the past decade mutations in genes encoding three ion channels, CACN1AS, SCN4A and KCNJ2, have been identified and account for at least 70% of the identified cases of PP and several allelic disorders. No prospective clinical studies have followed sufficiently large cohorts with characterized molecular lesions to draw precise conclusions. We summarize current knowledge of the clinical diagnosis, molecular genetics, genotype-phenotype correlations, pathophysiology and treatment in the PPs. We focus on unresolved issues including (i) Are there additional ion channel defects in cases without defined mutations? (ii) What is the mechanism for depolarization-induced weakness in Hypo PP? and finally (iii) Will detailed electrophysiological studies be able to correctly identify specific channel mutations? Understanding the pathophysiology of the potassium-sensitive PPs ought to reduce genetic complexity, allow subjects to be stratified during future clinical trials and increase the likelihood of observing true clinical effects. Ideally, therapy for the PPs will prevent attacks, avoid permanent weakness and improve quality of life. Moreover, understanding the skeletal muscle channelopathies will hopefully lead to insights into the more common central nervous system channel diseases such as migraine and epilepsy.
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120
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Pulkes T, Liolitsa D, Eunson LH, Rose M, Nelson IP, Rahman S, Poulton J, Marchington DR, Landon DN, Debono AG, Morgan-Hughes JA, Hanna MG. New phenotypic diversity associated with the mitochondrial tRNA(SerUCN) gene mutation. Neuromuscul Disord 2005; 15:364-71. [PMID: 15833431 DOI: 10.1016/j.nmd.2005.01.006] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2004] [Revised: 01/15/2005] [Accepted: 01/21/2005] [Indexed: 01/29/2023]
Abstract
We performed detailed clinical, histopathological, biochemical, in vitro translation and molecular genetic analysis in patients from two unrelated families harbouring the tRNA(SerUCN) 7472C-insertion mutation. Proband 1 developed a progressive neurodegenerative phenotype characterised by myoclonus, epilepsy, cerebellar ataxia and progressive hearing loss. Proband 2 had a comparatively benign phenotype characterised by isolated myopathy with exercise intolerance. Both patients had the 7472C-insertion mutation in identical proportions and they exhibited a similar muscle biochemical and histopathological phenotype. However, proband 2 also had a previously unreported homoplasmic A to C transition at nucleotide position 7472 in the tRNA(SerUCN) gene. This change lengthens further the homopolymeric C run already expanded by the 7472C-insertion. These data extend the phenotypic range associated with the 7472C-insertion to include isolated skeletal myopathy, as well as a MERRF-like phenotype.
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MESH Headings
- Adolescent
- Adult
- DNA Mutational Analysis/methods
- DNA, Mitochondrial/genetics
- Electron Transport Complex IV/metabolism
- Electrophoresis/methods
- Female
- Humans
- Male
- Microscopy, Electron, Transmission/methods
- Mitochondria, Muscle/pathology
- Mitochondrial Encephalomyopathies/enzymology
- Mitochondrial Encephalomyopathies/genetics
- Mitochondrial Encephalomyopathies/pathology
- Mitochondrial Encephalomyopathies/physiopathology
- Mitochondrial Proteins/metabolism
- Muscle, Skeletal/enzymology
- Muscle, Skeletal/pathology
- Muscle, Skeletal/ultrastructure
- Mutation
- Nucleic Acid Conformation
- Phenotype
- RNA, Transfer, Ser/chemistry
- RNA, Transfer, Ser/genetics
- Serine/metabolism
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121
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Uyl-de Groot CA, Vermorken JB, Hanna MG, Verboom P, Groot MT, Bonsel GJ, Meijer CJLM, Pinedo HM. Immunotherapy with autologous tumor cell-BCG vaccine in patients with colon cancer: a prospective study of medical and economic benefits. Vaccine 2005; 23:2379-87. [PMID: 15755632 DOI: 10.1016/j.vaccine.2005.01.015] [Citation(s) in RCA: 84] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
We have completed a multicenter, randomized controlled phase III clinical trial in Stages II and III colon cancer patients with active specific immunotherapy (ASI) using autologous tumor cells with an immunomodulating adjuvant bacillus Callmette-Guerin (BCG) vaccine (OncoVAX) in an adjuvant setting. In this study, patients were randomized to receive either OncoVAX therapy or no therapy after surgical resection of the primary tumor and stratified by stage of disease. Since the biologic essence of the effective tumor immunotherapy is the presence in the vaccine of a minimum number of viable, metabolically active, autologous tumor cells, the processing of the vaccine product, occurred within 48 h after surgery. Analysis of prognostic benefit in the pivotal phase III trial, with a 5.8 year median follow-up, showed that a beneficial effect of OncoVAX is statistically significant for all endpoints including recurrence-free interval, overall survival, and recurrence-free survival in Stage II colon cancer patients. Surgery alone cures approximately 65% of Stage II (Dukes B2, B3) colon cancer patients. In the remaining patients, OncoVAX in an adjuvant setting, significantly prolongs recurrence-free interval (57.1% relative risk reduction) and significantly improves 5-year overall survival and recurrence-free survival. No statistically significant prognostic benefits were achieved in Stage III (Duke's C1-C3) patients. A health economics assessment was performed on these results in Stage II colon cancer patients using disease-free survival and overall survival (for the entire intent-to-treat population). Cost-effectiveness, cost-utility and sensitivity analysis were applied with, cost of life years, recurrence-free life years and quality adjusted life years (QALYs) as the primary endpoints to this analysis. The perspective of the economic analysis was the current direct medical cost established by the health care providers. The introduction of new technologies often leads to additional costs. This report verified that the use of OncoVAX for patients with Stage II colon cancer not only has significant prognostic benefit and positive clinical outcomes, but also showed that OncoVAX therapy yields impressive health economics benefits.
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122
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Abstract
Ion channels are membrane-bound proteins that perform key functions in virtually all human cells. Such channels are critically important for the normal function of the excitable tissues of the nervous system, such as muscle and brain. Until relatively recently it was considered that dysfunction of ion channels in the nervous system would be incompatible with life. However, an increasing number of human diseases associated with dysfunctional ion channels are now recognised. Such neurological channelopathies are frequently genetically determined but may also arise through autoimmune mechanisms. In this article clinical, genetic, immunological, and electrophysiological aspects of this expanding group of neurological disorders are reviewed. Clinical situations in which a neurological channelopathy should enter into the differential diagnosis are highlighted. Some practical guidance on how to investigate and treat this complex group of disorders is also included.
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123
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Pulkes T, Liolitsa D, Wills AJ, Hargreaves I, Heales S, Hanna MG. Nonsense mutations in mitochondrial DNA associated with myalgia and exercise intolerance. Neurology 2005; 64:1091-2. [PMID: 15781840 DOI: 10.1212/01.wnl.0000154471.33156.55] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
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124
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Kinali M, Jungbluth H, Eunson LH, Sewry CA, Manzur AY, Mercuri E, Hanna MG, Muntoni F. Expanding the phenotype of potassium channelopathy: severe neuromyotonia and skeletal deformities without prominent Episodic Ataxia. Neuromuscul Disord 2004; 14:689-93. [PMID: 15351427 DOI: 10.1016/j.nmd.2004.06.007] [Citation(s) in RCA: 38] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2003] [Revised: 05/25/2004] [Accepted: 06/08/2004] [Indexed: 10/26/2022]
Abstract
We report an unusual family in which the same point mutation in the voltage-gated potassium channel gene KCNA1 resulted in markedly different clinical phenotypes. The propositus presented in infancy with marked muscle stiffness, motor developmental delay, short stature, skeletal deformities, muscle hypertrophy and muscle rippling on percussion. He did not experience episodic ataxia. His mother presented some years later with typical features of Episodic Ataxia type 1 (EA1), with episodes of ataxia lasting a few minutes provoked by exercise. On examination she had myokymia, joint contractures and mild skeletal deformities. A heterozygous point mutation in the voltage-gated K(+) channel (KCNA1) gene (ACG-AGG, Thr226Arg) was found in both. We conclude that mutations in the potassium channel gene (KCNA1) can cause severe neuromyotonia resulting in marked skeletal deformities even if episodic ataxia is not prominent.
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125
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Roedling S, Pearl D, Manji H, Hanna MG, Holton JL, Miller RF. Unusual muscle disease in HIV infected patients. Sex Transm Infect 2004; 80:315-7. [PMID: 15295133 PMCID: PMC1744880 DOI: 10.1136/sti.2003.008474] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022] Open
Abstract
Two patients presented with proximal muscle weakness, a normal or minor elevation of creatine phosphokinase (CPK) and normal findings on electromyography. Muscle biopsy in one patient revealed CD8+ polymyositis, and in the other showed ddI induced myopathy. These cases illustrate the importance of muscle biopsy in identifying the underlying pathology in HIV infected patients with muscle weakness and little or no abnormality in laboratory investigations.
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