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Krumhansl KA, Brooks CM, Lowen JB, O’Brien JM, Wong MC, DiBacco C. Loss, resilience and recovery of kelp forests in a region of rapid ocean warming. Ann Bot 2024; 133:73-92. [PMID: 37952103 PMCID: PMC10921841 DOI: 10.1093/aob/mcad170] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/27/2023] [Accepted: 11/08/2023] [Indexed: 11/14/2023]
Abstract
BACKGROUND AND AIMS Changes in kelp abundances on regional scales have been highly variable over the past half-century owing to strong effects of local and regional drivers. Here, we assess patterns and dominant environmental variables causing spatial and interspecific variability in kelp persistence and resilience to change in Nova Scotia over the past 40 years. METHODS We conducted a survey of macrophyte abundance at 251 sites spanning the Atlantic coast of Nova Scotia from 2019 to 2022. We use this dataset to describe spatial variability in kelp species abundances, compare species occurrences to surveys conducted in 1982 and assess changes in kelp abundance over the past 22 years. We then relate spatial and temporal patterns in abundance and resilience to environmental metrics. KEY RESULTS Our results show losses of sea urchins and the cold-tolerant kelp species Alaria esculenta, Saccorhiza dermatodea and Agarum clathratum in Nova Scotia since 1982 in favour of the more warm-tolerant kelps Saccharina latissima and Laminaria digitata. Kelp abundances have increased slightly since 2000, and Saccharina latissima and L. digitata are widely abundant in the region today. The highest kelp cover occurs on wave-exposed shores and at sites where temperatures have remained below thresholds for growth (21 °C) and mortality (23 °C). Moreover, kelp has recovered from turf dominance following losses at some sites during a warm period from 2010 to 2012. CONCLUSIONS Our results indicate that dramatic changes in kelp community composition and a loss of sea urchin herbivory as a dominant driver of change in the system have occurred in Nova Scotia over the past 40 years. However, a broad-scale shift to turf-dominance has not occurred, as predicted, and our results suggest that resilience and persistence are still a feature of kelp forests in the region despite rapid warming over the past several decades.
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Affiliation(s)
- K A Krumhansl
- Fisheries and Oceans Canada, Bedford Institute of Oceanography, Dartmouth, Nova Scotia, B2Y 4A2, Canada
| | - C M Brooks
- Fisheries and Oceans Canada, Bedford Institute of Oceanography, Dartmouth, Nova Scotia, B2Y 4A2, Canada
| | - J B Lowen
- Fisheries and Oceans Canada, Bedford Institute of Oceanography, Dartmouth, Nova Scotia, B2Y 4A2, Canada
| | - J M O’Brien
- Fisheries and Oceans Canada, Bedford Institute of Oceanography, Dartmouth, Nova Scotia, B2Y 4A2, Canada
| | - M C Wong
- Fisheries and Oceans Canada, Bedford Institute of Oceanography, Dartmouth, Nova Scotia, B2Y 4A2, Canada
| | - C DiBacco
- Fisheries and Oceans Canada, Bedford Institute of Oceanography, Dartmouth, Nova Scotia, B2Y 4A2, Canada
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Miller VE, Loring M, Morris SN, Isaacson KB, Wong MC. Intra-operative Factors Identified During Laparoscopy Hysterectomy are Correlated With Increased Post-operative Pain and Opioid Use. J Minim Invasive Gynecol 2019. [DOI: 10.1016/j.jmig.2019.09.714] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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3
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Lee AP, Yang F, Fan YT, Wong MC, Wong RH. P1822Pocket-size mobile echocardiographic device screening for thoracic aortic aneurysm in asymptomatic hypertensive patients. Eur Heart J 2019. [DOI: 10.1093/eurheartj/ehz748.0574] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Abstract
Background
Patients with hypertension may develop thoracic aortic aneurysm (TAA) that can be asymptomatic but potentially life-threatening. We sought to assess the prevalence of asymptomatic TAA among hypertensive patients and define the effectiveness of a TAA point-of-care screening program using pocket-size mobile echocardiographic (PME) devices.
Methods
We prospectively performed transthoracic echocardiography for TAA screening using a PME device on 1529 hypertensive patients (age, 62y [30y to 85y], 824 men) who attended our hypertension specialist clinic between June 2016 and July 2018. Measurement of the dimensions of the aortic sinus, sinotubular junction, ascending aorta, aortic arch, and descending thoracic aorta were obtained through multiple standard echo views.
Results
The prevalence of TAA (defined as maximum aortic diameter of ≥4.5cm and/or >50% diameter of the adjacent aorta) in our study population was 7.3% (111/1529), with distal ascending aorta as the most frequent location (Figure). Multiple logistic regression analysis identified male gender, older age, and presence of heart valve disease as independent factors associated with TAA (all p<0.05).
Figure 1
Conclusions
Asymptomatic TAA is common among asymptomatic hypertensive patients. Point-of-care use of PME device is effective in detecting TAA in a clinic setting. Such approach may be useful for early detection of TAA among at-risk patients allowing aggressive blood pressure control and early surgical intervention to prevent catastrophic complications such as aortic dissection or rupture.
Acknowledgement/Funding
Health and Medical Research Fund of the Hong Kong Government
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Affiliation(s)
- A P Lee
- The Chinese University of Hong Kong, Shatin, Hong Kong
| | - F Yang
- The Chinese University of Hong Kong, Shatin, Hong Kong
| | - Y T Fan
- The Chinese University of Hong Kong, Shatin, Hong Kong
| | - M C Wong
- The Chinese University of Hong Kong, Shatin, Hong Kong
| | - R H Wong
- The Chinese University of Hong Kong, Shatin, Hong Kong
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Terveer EM, Fallon M, Kraakman MEM, Ormond A, Fitzpatrick M, Caljouw MAA, Martin A, van Dorp SM, Wong MC, Kuijper EJ, Fitzpatrick F. Spread of ESBL-producing Escherichia coli in nursing home residents in Ireland and the Netherlands may reflect infrastructural differences. J Hosp Infect 2019; 103:160-164. [PMID: 31077778 DOI: 10.1016/j.jhin.2019.05.003] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/2019] [Accepted: 05/01/2019] [Indexed: 12/29/2022]
Abstract
A prevalence study in two nursing homes (one each in the Netherlands and Ireland) found four (11%) Dutch and six (9%) Irish residents colonized with 11 extended-spectrum beta-lactamase-producing Escherichia coli, 10 of which contained CTX-M-15. Four Dutch isolates, from three residents of the same ward, belonged to E. coli O25:H4, sequence type (ST) 131 and were part of the same cluster type by whole-genome sequencing. Four Irish residents on three different wards were colonized with an identical E. coli O89:H9, ST131, complex type 1478. Cross-transmission between three Irish wards may reflect differences in nursing home infrastructure, specifically communal areas and multi-bedded resident rooms.
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Affiliation(s)
- E M Terveer
- Department of Medical Microbiology, Leiden University Medical Centre, Leiden, the Netherlands.
| | - M Fallon
- Department of Clinical Microbiology, Royal College of Surgeons in Ireland, Dublin, Ireland
| | - M E M Kraakman
- Department of Medical Microbiology, Leiden University Medical Centre, Leiden, the Netherlands
| | - A Ormond
- Department of Clinical Microbiology, Beaumont Hospital, Dublin, Ireland
| | - M Fitzpatrick
- Department of Clinical Microbiology, Beaumont Hospital, Dublin, Ireland
| | - M A A Caljouw
- Department of Public Health and Primary Care, Leiden University Medical Centre, Leiden, the Netherlands
| | - A Martin
- Department of Geriatric and Stroke Medicine, Beaumont Hospital, Dublin, Ireland; Department of Geriatric and Stroke Medicine, Royal College of Surgeons in Ireland, Dublin, Ireland
| | - S M van Dorp
- Department of Medical Microbiology, Leiden University Medical Centre, Leiden, the Netherlands
| | - M C Wong
- Department of Medical Microbiology, Leiden University Medical Centre, Leiden, the Netherlands
| | - E J Kuijper
- Department of Medical Microbiology, Leiden University Medical Centre, Leiden, the Netherlands
| | - F Fitzpatrick
- Department of Clinical Microbiology, Royal College of Surgeons in Ireland, Dublin, Ireland; Department of Clinical Microbiology, Beaumont Hospital, Dublin, Ireland
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Chang WC, Lee HC, Chan SI, Chiu SY, Lee HM, Chan KW, Wong MC, Chan KL, Yeung WS, Choy LW, Chong SY, Siu MW, Lo TL, Yan WC, Ng MK, Poon LT, Pang PF, Lam WC, Wong YC, Chung WS, Mo YM, Lui SY, Hui LM, Chen EYH. Negative symptom dimensions differentially impact on functioning in individuals at-risk for psychosis. Schizophr Res 2018; 202:310-315. [PMID: 29935882 DOI: 10.1016/j.schres.2018.06.041] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/01/2017] [Revised: 04/20/2018] [Accepted: 06/14/2018] [Indexed: 12/24/2022]
Affiliation(s)
- W C Chang
- Department of Psychiatry, The University of Hong Kong, Queen Mary Hospital, Hong Kong; State Key Laboratory of Brain and Cognitive Sciences, The University of Hong Kong, Hong Kong.
| | - H C Lee
- Department of Psychiatry, The University of Hong Kong, Queen Mary Hospital, Hong Kong
| | - S I Chan
- Department of Psychiatry, The University of Hong Kong, Queen Mary Hospital, Hong Kong
| | - S Y Chiu
- Department of Psychiatry, The University of Hong Kong, Queen Mary Hospital, Hong Kong
| | - H M Lee
- Department of Psychiatry, The University of Hong Kong, Queen Mary Hospital, Hong Kong
| | - K W Chan
- Department of Psychiatry, The University of Hong Kong, Queen Mary Hospital, Hong Kong; State Key Laboratory of Brain and Cognitive Sciences, The University of Hong Kong, Hong Kong
| | - M C Wong
- Department of Psychiatry, Queen Mary Hospital, Hong Kong
| | - K L Chan
- Department of Psychiatry, Queen Mary Hospital, Hong Kong
| | - W S Yeung
- Department of Psychiatry, Pamela Youde Nethersole Eastern Hospital, Hong Kong
| | - L W Choy
- Department of Psychiatry, Pamela Youde Nethersole Eastern Hospital, Hong Kong
| | - S Y Chong
- Department of Psychiatry, Kwai Chung Hospital, Hong Kong
| | - M W Siu
- Department of Psychiatry, Kwai Chung Hospital, Hong Kong
| | - T L Lo
- Department of Psychiatry, Kwai Chung Hospital, Hong Kong
| | - W C Yan
- Department of Psychiatry, Kowloon Hospital, Hong Kong
| | - M K Ng
- Department of Psychiatry, Kowloon Hospital, Hong Kong
| | - L T Poon
- Department of Psychiatry, United Christian Hospital, Hong Kong
| | - P F Pang
- Department of Psychiatry, United Christian Hospital, Hong Kong
| | - W C Lam
- Department of Psychiatry, United Christian Hospital, Hong Kong
| | - Y C Wong
- Department of Psychiatry, Tai Po Hospital, Hong Kong
| | - W S Chung
- Department of Psychiatry, Tai Po Hospital, Hong Kong
| | - Y M Mo
- Department of Psychiatry, Alice Ho Miu Ling Nethersole Hospital, Hong Kong
| | - S Y Lui
- Department of Psychiatry, Castle Peak Hospital, Hong Kong
| | - L M Hui
- Department of Psychiatry, The University of Hong Kong, Queen Mary Hospital, Hong Kong
| | - E Y H Chen
- Department of Psychiatry, The University of Hong Kong, Queen Mary Hospital, Hong Kong; State Key Laboratory of Brain and Cognitive Sciences, The University of Hong Kong, Hong Kong
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Abstract
Aims and MethodThe study was intended to rectify the lack of data on how Chinese people experience the stigma of mental illness. A questionnaire on perceived stigmatisation, experiences of rejection and ways of coping with stigma was completed by 193 persons attending a psychiatric out-patient clinic in Hong Kong.ResultsMost of the participants were aware of the stigma associated with mental illness, but experiences of rejection were relatively less frequent. Eleven per cent of the respondents indicated that they were neglected by health care professionals and 8% had been avoided by family members. The most frequently reported coping method was maintaining secrecy about the illness.Clinical ImplicationsIn China, people with mental health problems experience stigma in various degrees. However, some of the people surveyed expressed feelings of relief that others were supportive and sympathetic towards their illness. Mental health professionals should maintain optimism in helping their patients to cope with the stigma.
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Jiang ZD, Ajami NJ, Petrosino JF, Jun G, Hanis CL, Shah M, Hochman L, Ankoma-Sey V, DuPont AW, Wong MC, Alexander A, Ke S, DuPont HL. Randomised clinical trial: faecal microbiota transplantation for recurrent Clostridum difficile infection - fresh, or frozen, or lyophilised microbiota from a small pool of healthy donors delivered by colonoscopy. Aliment Pharmacol Ther 2017; 45:899-908. [PMID: 28220514 DOI: 10.1111/apt.13969] [Citation(s) in RCA: 126] [Impact Index Per Article: 18.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/07/2016] [Revised: 12/29/2016] [Accepted: 01/14/2017] [Indexed: 12/14/2022]
Abstract
BACKGROUND Faecal microbiota transplantation (FMT) has become routine in managing recurrent C. difficile infection (CDI) refractory to antibiotics. AIM To compare clinical response and improvements in colonic microbiota diversity in subjects with recurrent CDI using different donor product. METHODS Seventy-two subjects with ≥3 bouts of CDI were randomised in a double-blind study to receive fresh, frozen or lyophilised FMT product via colonoscopy from 50 g of stool per treatment from eight healthy donors. Recipients provided stools pre- and 7, 14 and 30 days post-FMT for C. difficile toxin and, in a subset, microbiome composition by 16S rRNA gene profiling. RESULTS Overall resolution of CDI was 87% during 2 months of follow-up after FMT. Stool samples before FMT had significantly decreased bacterial diversity with a high proportion of Proteobacteria compared to donors. Cure rates were highest for the group receiving fresh product seen in 25/25 (100%), lowest for the lyophilised product 16/23 (78%; P = 0.022 vs. fresh and 0.255 vs. frozen) and intermediate for frozen product 20/24 (P = 0.233 vs. fresh). Microbial diversity was reconstituted by day 7 in the subjects receiving fresh or frozen product. Improvement in diversity was seen by day 7 in those randomised to lyophilised material with reconstitution by 30 days. CONCLUSIONS Comparative efficacy in faecal microbiota transplantation was observed in subjects receiving fresh or frozen faecal product from the same donors. The lyophilised product had a slightly lowered efficacy compared with fresh product, but it resembled other treatments in microbial restoration 1 month after faecal microbiota transplantation.
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Affiliation(s)
- Z D Jiang
- University of Texas School of Public Health, Houston, TX, USA
| | - N J Ajami
- Baylor College of Medicine, Houston, TX, USA
| | | | - G Jun
- University of Texas School of Public Health, Houston, TX, USA
| | - C L Hanis
- University of Texas School of Public Health, Houston, TX, USA
| | - M Shah
- University of Texas School of Public Health, Houston, TX, USA
| | - L Hochman
- Baylor St Luke's Medical Center, Houston, TX, USA
| | - V Ankoma-Sey
- Baylor St Luke's Medical Center, Houston, TX, USA
| | - A W DuPont
- University of Texas Medical School, Houston, TX, USA
| | - M C Wong
- Baylor College of Medicine, Houston, TX, USA
| | - A Alexander
- Baylor St Luke's Medical Center, Houston, TX, USA
| | - S Ke
- University of Texas School of Public Health, Houston, TX, USA
| | - H L DuPont
- University of Texas School of Public Health, Houston, TX, USA.,Baylor College of Medicine, Houston, TX, USA.,Baylor St Luke's Medical Center, Houston, TX, USA.,Kelsey Research Foundation, Houston, TX, USA
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8
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Abstract
The overall goal of this project is the development of a new methodology for translating advances in molecular level understanding of toxicological responses into a predictive tool for dose response in whole animals and humans exposed to single compounds or mixtures of compounds. The methodology incorporates a mechanistic cellular level model into a PBPK (physiologically based pharmacokinetic) model which simultaneously guides the development of an in vitro cell culture analog (CCA) to the PBPK. Where the PBPK specifies an organ, (e.g., liver) the in vitro or CCA system contains a compartment with the appropriate cell or cell population (e.g., hepatocytes for the liver). The CCA has significant advantages over other in vitro systems and PBPK systems used independently for evaluating metabolic responses to drugs or potentially toxic chemicals where the exchange of metabolites between organs is likely to be important. The CCA system is superior to a PBPK because an a priori description of complete metabolism is not required and secondary, unexpected interactions can be detected. The CCA system, unlike other in vitro systems, gives a dynamic response that realistically simulates in vivo interactions between organs. Furthermore, the CCA allows dosing on the same basis as animal tests (e.g., milligrams per kilogram of body mass equivalent). Because the construction of a CCA is guided by a PBPK, this approach allows extrapolation to low doses and across species, including extrapolation to humans. We have constructed a prototype system and have conducted proof-of-concept experiments using naphthalene as a test chemical. These experiments clearly demonstrate the ability to generate a reactive metabolite in one compartment and detect its effects (on LDH release and glutathione depletion) in a second compartment. However, this prototype device would be expensive to replicate and requires nearly constant supervision from a trained investigator. For this concept to replace animals an inexpensive, self-regulating device is needed. An initial design to accomplish this goal is described as well as the corresponding model using naphthalene as a test compound. (c) 1996 John Wiley & Sons, Inc.
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Affiliation(s)
- M L Shuler
- School of Chemical Engineering, Cornell University, Ithaca, New York 14853-5201
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Moe KT, Yin NO, Naylynn TM, Khairunnisa K, Wutyi MA, Gu Y, Atan MSM, Wong MC, Koh TH, Wong P. Nox2 and Nox4 mediate tumour necrosis factor-α-induced ventricular remodelling in mice. J Cell Mol Med 2012; 15:2601-13. [PMID: 21251215 PMCID: PMC4373429 DOI: 10.1111/j.1582-4934.2011.01261.x] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022] Open
Abstract
Reactive oxygen species (ROS) and pro-inflammatory cytokines are crucial in ventricular remodelling, such as inflammation-associated myocarditis. We previously reported that tumour necrosis factor-α (TNF-α)-induced ROS in human aortic smooth muscle cells is mediated by NADPH oxidase subunit Nox4. In this study, we investigated whether TNF-α-induced ventricular remodelling was mediated by Nox2 and/or Nox4. An intravenous injection of murine TNF-α was administered to a group of mice and saline injection was administered to controls. Echocardiography was performed on days 1, 7 and 28 post-injection. Ventricular tissue was used to determine gene and protein expression of Nox2, Nox4, ANP, interleukin (IL)-1β, IL-2, IL-6, TNF-α and to measure ROS. Nox2 and Nox4 siRNA were used to determine whether or not Nox2 and Nox4 mediated TNF-α-induced ROS and upregulation of IL-1β and IL-6 in adult human cardiomyocytes. Echocardiography showed a significant increase in left ventricular end-diastolic and left ventricular end-systolic diameters, and a significant decrease in the ejection fraction and fractional shortening in mice 7 and 28 days after TNF-α injection. These two groups of mice showed a significant increase in ventricular ROS, ANP, IL-1β, IL-2, IL-6 and TNF-α proteins. Nox2 and Nox4 mRNA and protein levels were also sequentially increased. ROS was significantly decreased by inhibitors of NADPH oxidase, but not by inhibitors of other ROS production systems. Nox2 and Nox4 siRNA significantly attenuated TNF-α-induced ROS and upregulation of IL-1β and IL-6 in cardiomyocytes. Our study highlights a novel TNF-α-induced chronic ventricular remodelling mechanism mediated by sequential regulation of Nox2 and Nox4 subunits.
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Affiliation(s)
- K T Moe
- Research and Development Unit, National Heart Centre Singapore, Singapore.
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De Silva DA, Manzano JJF, Chang HM, Wong MC. Reconsidering recent myocardial infarction as a contraindication for IV stroke thrombolysis. Neurology 2011; 76:1838-40. [DOI: 10.1212/wnl.0b013e31821ccc72] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
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Narasimhalu K, Effendy S, Sim CH, Lee JM, Chen I, Hia SB, Xue HL, Corrales MP, Chang HM, Wong MC, Chen CP, Tan EK. A randomized controlled trial of rivastigmine in patients with cognitive impairment no dementia because of cerebrovascular disease. Acta Neurol Scand 2010; 121:217-24. [PMID: 19951274 DOI: 10.1111/j.1600-0404.2009.01263.x] [Citation(s) in RCA: 45] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
OBJECTIVES The safety and efficacy of early acetylcholinesterase inhibitors therapy in patients with cognitive impairment no dementia (CIND) after a cerebrovascular accident have not been examined. In this study, we investigated the safety and efficacy of rivastigmine in cognition, particularly executive function in patients with CIND because of cerebrovascular disease. METHODS This study was a 24-week, double-blind, randomized, placebo-controlled trial of ischemic stroke patients seen at a tertiary hospital who had cognitive impairment no dementia because of cerebrovascular disease. The intervention was either rivastigmine or placebo up to 9 mg/day. The primary outcome of interest was mean change from baseline in the Ten-Point Clock Drawing and Color Trails 1 and 2. RESULTS Fifty patients were randomized into rivastigmine (n = 25) and placebo (n = 25) arms. Patients in the rivastigmine group showed statistically significant improvement (1.70 vs 0.13, P = 0.02) on the animal subtask of the verbal fluency measure compared with placebo. There was also a trend (non-significant) towards improvement in Color Trails II. CONCLUSIONS In this pilot study, we demonstrated that rivastigmine was well tolerated in patients with CIND because of cerebrovascular disease and may potentially improve executive functioning.
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Affiliation(s)
- K Narasimhalu
- Center for Molecular Epidemiology, National University of Singapore, Singapore
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12
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Soong YK, Wong MC, Hsueh S, Chen WJ. Placental site trophoblastic tumour of the uterus with a distinctive glomerular lesion and fatal outcome. J OBSTET GYNAECOL 2009. [DOI: 10.3109/01443618809151336] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
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13
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Tan EK, Lee J, Chen CP, Wong MC, Zhao Y. Case control analysis of LRRK2 Gly2385Arg in Alzheimer's disease. Neurobiol Aging 2009; 30:501-2. [PMID: 17720280 DOI: 10.1016/j.neurobiolaging.2007.07.010] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2007] [Revised: 07/10/2007] [Accepted: 07/18/2007] [Indexed: 10/22/2022]
Abstract
Alzheimer's disease (AD) pathology has been described in Parkinson's disease (PD) patients with leucine-rich repeat kinase-2 (LRRK2) mutations. A common LRRK2 Gly2385Arg variant has been widely shown to be associated with a twofold increased risk of PD in various Asian populations. In a case control study, the frequency of the heterozygous Gly2385Arg genotype was demonstrated in 4.3% of AD compared to 4.5% in controls (odds ratio=0.94, 95% CI 0.37-2.42, p=1.0). The Gly2385Arg variant does not appear to modulate the risk of AD in our population.
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Affiliation(s)
- E K Tan
- Department of Neurology, Singapore General Hospital, Singapore.
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Moe KT, Woon FP, De Silva DA, Wong P, Koh TH, Kingwell B, Chin-Dusting J, Wong MC. Association of acute ischemic stroke with the MTHFR C677T polymorphism but not with NOS3 gene polymorphisms in a Singapore population. Eur J Neurol 2008; 15:1309-14. [DOI: 10.1111/j.1468-1331.2008.02308.x] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
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15
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Hankey GJ, Algra A, Chen C, Wong MC, Cheung R, Wong L, Divjak I, Ferro J, de Freitas G, Gommans J, Groppa S, Hill M, Spence D, Lees K, Lisheng L, Navarro J, Ranawaka U, Ricci S, Schmidt R, Slivka A, Tan K, Tsiskaridze A, Uddin W, Vanhooren G, Xavier D, Armitage J, Hobbs M, Le M, Sudlow C, Wheatley K, Yi Q, Bulder M, Eikelboom JW, Hankey GJ, Ho WK, Jamrozik K, Klijn K, Koedam E, Langton P, Nijboer E, Tuch P, Pizzi J, Tang M, Antenucci M, Chew Y, Chinnery D, Cockayne C, Loh K, McMullin L, Smith F, Schmidt R, Chen C, Wong MC, de Freitas G, Hankey GJ, Loh K, Song S. VITATOPS, the VITAmins TO prevent stroke trial: rationale and design of a randomised trial of B-vitamin therapy in patients with recent transient ischaemic attack or stroke (NCT00097669) (ISRCTN74743444). Int J Stroke 2008; 2:144-50. [PMID: 18705976 DOI: 10.1111/j.1747-4949.2007.00111.x] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
BACKGROUND Epidemiological studies suggest that raised plasma concentrations of total homocysteine (tHcy) may be a common, causal and treatable risk factor for atherothromboembolic ischaemic stroke, dementia and depression. Although tHcy can be lowered effectively with small doses of folic acid, vitamin B(12) and vitamin B(6), it is not known whether lowering tHcy, by means of B vitamin therapy, can prevent stroke and other major atherothromboembolic vascular events. AIM To determine whether the addition of B-vitamin supplements (folic acid 2 mg, B(6) 25 mg, B(12) 500 microg) to best medical and surgical management will reduce the combined incidence of stroke, myocardial infarction (MI) and vascular death in patients with recent stroke or transient ischaemic attack (TIA) of the brain or eye. DESIGN A prospective, international, multicentre, randomised, double blind, placebo-controlled clinical trial. SETTING One hundred and four medical centres in 20 countries on five continents. SUBJECTS Eight thousand (6600 recruited as of 5 January, 2006) patients with recent (<7 months) stroke (ischaemic or haemorrhagic) or TIA (brain or eye). RANDOMISATION Randomisation and data collection are performed by means of a central telephone service or secure internet site. INTERVENTION One tablet daily of either placebo or B vitamins (folic acid 2 mg, B(6) 25 mg, B(12) 500 mug). PRIMARY OUTCOME The composite of stroke, MI or death from any vascular cause, whichever occurs first. Outcome and serious adverse events are adjudicated blinded to treatment allocation. SECONDARY OUTCOMES TIA, unstable angina, revascularisation procedures, dementia, depression. STATISTICAL POWER: With 8000 patients followed up for a median of 2 years and an annual incidence of the primary outcome of 8% among patients assigned placebo, the study will have at least 80% power to detect a relative reduction of 15% in the incidence of the primary outcome among patients assigned B vitamins (to 6.8%/year), applying a two-tailed level of significance of 5%. CONCLUSION VITATOPS aims to recruit and follow-up 8000 patients between 1998 and 2008, and provide a reliable estimate of the safety and effectiveness of folic acid, vitamin B(12), and vitamin B(6) supplementation in reducing recurrent serious vascular events among a wide range of patients with TIA and stroke throughout the world.
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16
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Affiliation(s)
- E-K Tan
- Department of Neurology, Singapore General Hospital, Outram Road, Singapore 169608.
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Moe KT, Lim ST, Wong P, Chua T, DeSilva DA, Koh TH, Wong MC, Chin-Dusting J. Association analysis of endothelial nitric oxide synthase gene polymorphism with primary hypertension in a Singapore population. J Hum Hypertens 2006; 20:956-63. [PMID: 17024134 DOI: 10.1038/sj.jhh.1002096] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Vascular endothelial cells produce nitric oxide (NO), which contributes to the regulation of blood pressure and regional blood flow. Endothelial nitric oxide synthase (eNOS) gene polymorphisms are associated with coronary artery disease, but their linkage with primary hypertension is controversial. A total of 103 individuals with primary hypertension and 104 normotensive control subjects were studied in Singapore. The specific genotypes for G894T missense variant in exon 7, variable number tandem repeats (VNTR) in intron 4 (eNOS 4A/B/C) and T-786C in the promoter were isolated using allele-specific gene amplification and restriction fragment length polymorphism to examine the association of genotype and allelic frequency in both groups. Logistic regression analysis was also used to detect the association between genotypes and hypertension. Five genotypes of intron 4 VNTR (AA, AB, BB, AC and BC) were observed. Intron 4 B/B genotype was significantly associated with the hypertension group (P = 0.035), but disequilibrium of G894T and T-786C was absent between the two groups (P = 0.419 and P = 0.227), respectively. The overall distribution of allelic frequency differed significantly between the two groups, with four-repeat allele (4A) of intron 4 more frequent in the normotensive group than the hypertensive group (P = 0.019). Logistic regression analysis showed that intron 4 B/B genotype was significantly associated with systolic blood pressure of individuals with body mass index greater than 25 kg/m2 (P = 0.04). In conclusion, the eNOS 4 B/B genotype is a genetic susceptibility factor for primary hypertension in a Singapore population.
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Affiliation(s)
- K T Moe
- Research and Development Unit, National Heart Centre, Singapore, Singapore
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Tan EK, Zhao Y, Skipper L, Tan MG, Di Fonzo A, Sun L, Fook-Chong S, Tang S, Chua E, Yuen Y, Tan L, Pavanni R, Wong MC, Kolatkar P, Lu CS, Bonifati V, Liu JJ. The LRRK2 Gly2385Arg variant is associated with Parkinson’s disease: genetic and functional evidence. Hum Genet 2006; 120:857-63. [PMID: 17019612 DOI: 10.1007/s00439-006-0268-0] [Citation(s) in RCA: 127] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2006] [Accepted: 09/11/2006] [Indexed: 10/24/2022]
Abstract
Evidence of LRRK2 haplotypes associated with Parkinson's disease (PD) risk was recently found in the Chinese population from Singapore, and a common LRRK2 missense variant, Gly2385Arg, was independently detected as a putative risk factor for PD in the Chinese population from Taiwan. To test the association between the Gly2385Arg variant in a large case-control sample of Chinese ethnicity from Singapore, and to perform functional studies of the wild type and Gly2385Arg LRRK2 protein in human cell lines. In a case-control study involving 989 Chinese subjects, the frequency of the heterozygous Gly2385Arg genotype was higher in PD compared to controls (7.3 vs. 3.6%, odds ratio = 2.1, 95% CI: 1.1-3.9, P = 0.014); these values yield an estimated population attributable risk (PAR) of approximately 4%. In a multivariate logistic regression analysis with the disease group (PD vs. controls) as the dependent variable and the genotype as an independent factor with adjustments made for the effect of age and gender, the heterozygous Gly2385Arg genotype remained associated with an increased risk of PD compared to wild type genotype (odds ratio = 2.67, 95% CI: 1.43-4.99, P = 0.002). The glycine at position 2385 is a candidate site for N-myristoylation, and the Gly2385Arg variant replaces the hydrophobic glycine with the hydrophilic arginine, and increases the net positive charge of the LRRK2 WD40 domain. In transfection studies, we demonstrated that both the wild type and Gly2385Arg variant LRRK2 protein localize to the cytoplasm and form aggregates. However, under condition of oxidative stress, the Gly2385Arg variant was more toxic and associated with a higher rate of apoptosis. Our study lends support to the contention that the Gly2385Arg is a common risk factor for PD in the Chinese population. Our bioinformatics and in-vitro studies also suggest that the Gly2385Arg variant is biologically relevant and it might act through pro-apoptotic mechanisms.
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Affiliation(s)
- E K Tan
- Department of Neurology, Singapore General Hospital, Outram Road, Singapore, Singapore
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Moe KT, Aulia S, Jiang F, Chua YL, Koh TH, Wong MC, Dusting GJ. Differential upregulation of Nox homologues of NADPH oxidase by tumor necrosis factor-alpha in human aortic smooth muscle and embryonic kidney cells. J Cell Mol Med 2006; 10:231-9. [PMID: 16563235 PMCID: PMC3933115 DOI: 10.1111/j.1582-4934.2006.tb00304.x] [Citation(s) in RCA: 80] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023] Open
Abstract
NADPH oxidases are important sources of vascular superoxide, which has been linked to the pathogenesis of atherosclerosis. Previously we demonstrated that the Nox4 subunit of NADPH oxidase is a critical catalytic component for superoxide production in quiescent vascular smooth muscle cells. In this study we sought to determine the role of Nox4 in superoxide production in human aortic smooth muscle cells (AoSMC) and embryonic kidney (HEK293) cells under proinflammatory conditions. Incubation with tumor necrosis factor-α (TNF-α, 10 ng/ml) for 12h increased superoxide production in both cell types, whereas angiotensin II, platelet-derived growth factor or interleukin-1β had little effects. Superoxide production was completely abolished by the NADPH oxidase inhibitors diphenyline iodonium and apocynin, but not by inhibitors of xanthine oxidase, nitric oxide synthase or mitochondrial electron transport. TNF-α upregulated the expression of Nox4 in AoSMC at both message and protein levels, while Nox1 and Nox2 were unchanged. In contrast, upregulation of Nox2 appeared to mediate the enhanced superoxide production by TNF-α in HEK293 cells. We suggest that Nox4 may be involved in increased superoxide generation in vascular smooth muscle cells under proinflammatory conditions.
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Affiliation(s)
- K T Moe
- Research and Development Unit, National Heart CentreSingapore
| | - S Aulia
- Research and Development Unit, National Heart CentreSingapore
| | - F Jiang
- Research and Development Unit, National Heart CentreSingapore
- Bernard O'Brien Institute of Microsurgery, St. Vincent's Hospital, The University of MelbourneVictoria, Australia
| | - Y L Chua
- Cardiothoracic Surgery Department, National Heart CentreSingapore
| | - T H Koh
- Cardiology Department, National Heart CenterSingapore
| | - M C Wong
- National Neuroscience Institute, Singapore General Hospital CampusSingapore
| | - G J Dusting
- Howard Florey Institute, University of Melbourne, VictoriaAustralia
- Bernard O'Brien Institute of Microsurgery, St. Vincent's Hospital, The University of MelbourneVictoria, Australia
- * Correspondence to: Professor Gregory J. DUSTING Bernard O'Brien Institute of Microsurgery, the University of Melbourne, 42 Fitzroy Street, Fitzroy, Victoria 3065, Australia Tel.: +61-3-9288 4062; Fax:+61-3-9416 0926 E-mail:
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Sharma V, Ong Benjamin KC, Wong MC, Wilder-Smith E. Headache characteristics in episodic ataxia. Eur J Neurol 2006; 13:e8. [PMID: 16879285 DOI: 10.1111/j.1468-1331.2006.01343.x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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21
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Lim SW, Zhao Y, Chua E, Law HY, Yuen Y, Pavanni R, Wong MC, Ng IS, Yoon CS, Puong KY, Lim SH, Tan EK. Genetic analysis of SCA2, 3 and 17 in idiopathic Parkinson's disease. Neurosci Lett 2006; 403:11-4. [PMID: 16687213 DOI: 10.1016/j.neulet.2006.04.019] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2006] [Revised: 03/31/2006] [Accepted: 04/14/2006] [Indexed: 10/24/2022]
Abstract
Recent reports of SCA2 and SCA3 patients who presented with levodopa responsive parkinsonism have generated considerable interest as they have implications for genetic testing. It is unclear whether ethnic race alone or founder effects within certain geographical region explain such an association. In this study, we conducted genetic analysis of SCA2, 3, 17 in an ethnic Chinese cohort with early onset and familial Parkinson's disease (PD) and healthy controls. A total of 191 subjects comprising of 91 PD and 100 healthy controls were examined. We identified one positive case of SCA2 in an early-onset sporadic PD patient who had CAG 36 repeats, yielding a prevalence of 2.2% in early-onset sporadic PD patients and less than 1.0% in our study PD population. The size of the repeats was lower than the expanded repeats (38-57) in SCA2 patients with ataxia in our population. All the children of the patient were physically normal even though some of them carried the repeat expansion of similar size. No cases and controls were positive for SCA3 and SCA17. We do not think routine screening of SCA2, SCA3 and SCA17 for all idiopathic PD patients is cost-effective in our ethnic Chinese population. However, SCA2 should be a differential diagnosis in young onset sporadic PD when genetic mutations of other known PD genes have been excluded.
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Affiliation(s)
- S W Lim
- Department of Neurology, Singapore General Hospital, Outram Road, Singapore 169608, Singapore
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Abstract
The authors propose "decreased-dose-intensity" PCV (procarbazine, lomustine [CCNU], and vincristine) chemotherapy for Asian patients with oligodendroglial tumors. In this study, all seven patients with oligodendroglioma (OD) and eight with anaplastic oligodendroglioma (AO) had objective responses or stable disease. Median progression-free survival was greater than 29 months (OD) and 36.5 months or greater (AO); 86% of patients with OD and 63% with AO remain progression-free. Twenty-four Common Toxicity Criteria Grade 3/4 adverse events were noted.
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Affiliation(s)
- A U Ty
- Department of Neurology, National Neuroscience Institute, Singapore General Hospital Campus, Singapore
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Tan EK, Yew K, Chua E, Shen H, Jamora RD, Lee E, Puong KY, Zhao Y, Pavanni R, Wong MC, Puvan K, Yih Y, Tan LCS. Analysis of PINK1 in Asian patients with familial parkinsonism. Clin Genet 2005; 68:468-70. [PMID: 16207217 DOI: 10.1111/j.1399-0004.2005.00500.x] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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Skipper L, Shen H, Chua E, Bonnard C, Kolatkar P, Tan LCS, Jamora RD, Puvan K, Puong KY, Zhao Y, Pavanni R, Wong MC, Yuen Y, Farrer M, Liu JJ, Tan EK. Analysis of LRRK2 functional domains in nondominant Parkinson disease. Neurology 2005; 65:1319-21. [PMID: 16247070 DOI: 10.1212/01.wnl.0000180517.70572.37] [Citation(s) in RCA: 55] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Abstract
A comprehensive sequence analysis of 29 exons that code for the functional domains of LRRK2 in 160 nondominant Parkinson disease (PD) patients was performed. Novel variant screening in a further 470 sporadic PD patients and 630 controls revealed two novel variants (R1067Q and IVS33 + 6 T>A), which are likely to be pathogenic in five patients. One patient presented initially with a typical essential tremor phenotype, expanding the phenotypic spectrum of LRRK2 mutations.
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Affiliation(s)
- L Skipper
- Department of Population Genetics, Genome Institute of Singapore, Singapore
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Tan EK, Puong KY, Chan DKY, Yew K, Fook-Chong S, Shen H, Ng PW, Woo J, Yuen Y, Pavanni R, Wong MC, Puvan K, Zhao Y. Impaired transcriptional upregulation of Parkin promoter variant under oxidative stress and proteasomal inhibition: clinical association. Hum Genet 2005; 118:484-8. [PMID: 16244875 DOI: 10.1007/s00439-005-0038-4] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2005] [Accepted: 07/12/2005] [Indexed: 12/01/2022]
Abstract
We provided data to show that the transcriptional activity of wildtype -258T in the parkin promoter region was significantly higher than the -258G variant in human cell lines. The transcriptional activity of wildtype -258T was significantly increased under oxidative stress by hydrogen peroxide, but this was not observed for the -258G variant. The transcriptional upregulation was significantly higher for wildtype -258T compared to -258G variant at 0.1, 0.2 and 0.4 mM of hydrogen peroxide. Similar results were obtained when the cells were treated with a proteasome inhibitor, MG132.Furthermore, in a case control study involving 753 subjects, we demonstrated that the parkin promoter -258G variant was associated with an increased risk of sporadic Parkinson's disease (PD) in the elderly ethnic Chinese population. Our clinical and laboratory data provide corroborative evidence that some older individuals who have the -258G variant may have a higher risk of developing PD.
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Affiliation(s)
- E K Tan
- Department of Neurology, Singapore General Hospital, Outram Road, 169608, Singapore, Singapore.
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Tan EK, Shen H, Tan LCS, Farrer M, Yew K, Chua E, Jamora RD, Puvan K, Puong KY, Zhao Y, Pavanni R, Wong MC, Yih Y, Skipper L, Liu JJ. The G2019S LRRK2 mutation is uncommon in an Asian cohort of Parkinson's disease patients. Neurosci Lett 2005; 384:327-9. [PMID: 15955629 DOI: 10.1016/j.neulet.2005.04.103] [Citation(s) in RCA: 118] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/17/2005] [Accepted: 04/30/2005] [Indexed: 11/18/2022]
Abstract
A common heterozygous leucine-rich repeat kinase 2 (LRRK2) mutation 6055G > A transition (G2019S) accounts for about 3-7% of familial Parkinson's disease (PD) and 1-1.6% sporadic PD in a number of European populations. To determine the prevalence of the G1019S mutation in our Asian population, we conducted genetic analysis of this mutation in 1000 PD and healthy controls. The G2019S mutation was not detected in any of our study subjects. The prevalence of G2019S mutation is rare (< 0.1%) in our population, suggesting that occurrence of this mutation may vary amongst different ethnic races. This has important clinical implication when implementing guidelines for genetic testing.
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Affiliation(s)
- E K Tan
- Department of Neurology, Clinical Research and Health Screening, Singapore General Hospital, Outram Road, Singapore.
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27
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Tan EK, Shen H, Tan JMM, Lim KL, Fook-Chong S, Hu WP, Paterson MC, Chandran VR, Yew K, Tan C, Yuen Y, Pavanni R, Wong MC, Puvan K, Zhao Y. Differential expression of splice variant and wild-type parkin in sporadic Parkinson's disease. Neurogenetics 2005; 6:179-84. [PMID: 16086186 DOI: 10.1007/s10048-005-0001-5] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2005] [Accepted: 06/01/2005] [Indexed: 10/25/2022]
Abstract
BACKGROUND Altered splicing of parkin under cellular stress could lead to changes in gene expression and altered protein activity. The causative role of parkin in sporadic Parkinson's disease (PD) is unknown. OBJECTIVES We described a parkin splice variant (SV) in the substantia nigra and leukocytes of sporadic PD patients. Using a case control methodology, we investigated the exon 4 SV (E4SV) and wild-type parkin expression in the leukocytes of sporadic PD patients and healthy individuals. METHODS/RESULTS We identified a parkin E4SV in the substantia nigra and leukocytes of sporadic PD patients and controls by reverse transcriptase-polymerase chain reaction (PCR). The exon 4 (122 bp) deletion resulted in a reading frame shift over the junction of exons 3-5 and a stop codon (tga) 17 bp downstream from exon 3. The translated truncated protein was associated with a total loss of the two-RING finger functional domain. Utilizing TaqMan real-time PCR with probes located across the junction of exons 3-4 or 3-5, we demonstrated an over-expression of E4SV/wild-type parkin ratio in the leukocytes of sporadic PD patients compared to age-, gender-, and race-matched controls (p<0.0005). A multivariate regression analysis demonstrated that the ratio of E4SV/wild-type parkin expression increased with age in PD patients, but this was not observed in the controls (p<0.0005). CONCLUSION The relative expression of E4SV/wild type parkin was increased in sporadic PD compared to healthy controls. Based on our observations, further functional studies to determine the pathophysiologic role of E4SV in sporadic PD patients will be of importance.
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Affiliation(s)
- E K Tan
- Department of Neurology, Singapore General Hospital, Outram Road, Singapore, 169608, Singapore.
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Tow BPB, Chang PCC, Mitra AK, Tay BK, Wong MC. Comparing 2-year outcomes of anterior cruciate ligament reconstruction using either patella-tendon or semitendinosus-tendon autografts: a non-randomised prospective study. J Orthop Surg (Hong Kong) 2005; 13:139-46. [PMID: 16131675 DOI: 10.1177/230949900501300206] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/03/2023] Open
Abstract
PURPOSE To compare the results of anterior cruciate ligament (ACL) reconstructions using either a patella-tendon autograft or a semitendinosus-tendon autograft. METHODS Based on surgeon experience and preference, 68 patients underwent ACL reconstruction using either a quadruple-strand semitendinosus autograft (n = 34) or a central one-third bone-patella tendon-bone autograft (n = 34). Each patient was assessed preoperatively and postoperatively at 3, 6, and 24 months using the International Knee Documentation Committee (IKDC) knee score, Biodex muscle strength and endurance testing, and the KT1000 instrumented arthrometer test of knee laxity to anterior translation. All assessments at the 2-year follow-up were performed by the same physician and physiotherapist. RESULTS While ACL reconstruction improved knee stability and IKDC knee scores significantly, there was no statistically significant difference between semitendinosus- and patella-tendon autograft reconstructions in terms of long-term knee score or laxity to anterior translation. Semitendinosus graft reconstruction was associated with less donor-site morbidity and hamstring weakness. Meniscectomy was associated with poorer long-term knee scores. CONCLUSION ACL reconstruction is associated with a significantly better IKDC knee score and laxity measurement at 2-year follow-up. However, we were unable to demonstrate a significantly better long-term outcome in knee score or laxity to anterior translation with either a patella-tendon autograft or a semitendinosus-tendon autograft.
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Affiliation(s)
- B P B Tow
- Department of Orthopaedic Surgery, Singapore General Hospital, Singapore
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Abstract
Information on prescribing pattern of antiparkinsonian medications and factors influencing neurologists' choice of such drugs are important considerations in evaluating healthcare cost of Parkinson's disease (PD). We surveyed neurologists' perceived factors influencing their choice of drugs and actual prescribing pattern in PD. Three hundred and six patients at a tertiary hospital, diagnosed with idiopathic PD and who were dispensed antiparkinsonian drugs during a 6-month period were randomly selected. Patient demographics, type and dose of medications were analysed. A questionnaire survey evaluating the factors influencing choice of medications was administered to neurologists who practiced at the institution. The study population had a mean age of 64.4 years (SD +/- 9.9 years), and more than 80% were at Hoehn & Yahr stage 2-3. 92.3% of the study population were receiving levodopa and monotherapy, with levodopa being the most common treatment regimen. Patients who were prescribed levodopa were significantly older and at a later stage of disease compared to those without levodopa (p < 0.05). Only 26.8% of patients were prescribed dopamine agonists. In the survey, the neurologists cited severity of symptoms, and patients' intolerance of side effects, and efficacy as the most important factors influencing their choice of drugs. However, the actual prescribing pattern revealed a strong positive correlation of drug usage with cost subsidy by the institution. While factors affecting drug usage in PD are well recognised, cost and efficacy of a drug appear to be overriding practical factors in influencing usage pattern in clinical practice.
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Affiliation(s)
- E K Tan
- Department of Neurology, Singapore General Hospital, National Neuroscience Institute, SingHealth, National University of Singapore, Singapore.
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Tan EK, Zhao Y, Puong KY, Law HY, Chan LL, Yew K, Shen H, Chandran VR, Yuen Y, Pavanni R, Wong MC, Ng IS. Expanded FMR1 alleles are rare in idiopathic Parkinson?s disease. Neurogenetics 2004; 6:51-2. [PMID: 15742217 DOI: 10.1007/s10048-004-0200-5] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
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Tan HW, Ty A, Goh SGN, Wong MC, Hong A, Chuah KL. Pineal yolk sac tumour with a solid pattern: a case report in a Chinese adult man with Down's syndrome. J Clin Pathol 2004; 57:882-4. [PMID: 15280413 PMCID: PMC1770394 DOI: 10.1136/jcp.2004.016659] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Abstract
Intracranial germ cell tumours are rare. The incidence of primary intracranial yolk sac tumour is even more uncommon, with only two reported cases being associated with Down's syndrome in the English literature. This report details the findings of yolk sac tumour in the pineal region affecting a 22 year old Chinese man with Down's syndrome. Histology revealed yolk sac tumour with only a solid pattern, potentially mimicking the more common germinoma in the pineal region. No other germ cell components were identified. This is the third report of intracranial yolk sac tumour manifesting in a patient with trisomy 21. The pathology of this tumour and its differential diagnoses are discussed.
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Affiliation(s)
- H W Tan
- Department of Pathology, Singapore General Hospital, Outram Road, Singapore 169608, Singapore
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Kang KB, Wang TT, Woon CT, Cheah ST, Lim YK, Moore XL, Wong MC. Celecoxib enhances brain tumour cell radiosensitivity leading to massive tumour necrosis. Ann Acad Med Singap 2004; 33:S19-20. [PMID: 15651189] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/01/2023]
Affiliation(s)
- K B Kang
- Division of Medical Science, National Cancer Centre, Singapore
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See SJ, Pan A, Seah A, Teo J, Chan LL, Wong MC. Case reports of two biopsy-proven patients with Creutzfeldt-Jakob disease in Singapore. Ann Acad Med Singap 2004; 33:651-5. [PMID: 15531964] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/01/2023]
Abstract
INTRODUCTION Creutzfeldt-Jakob disease (CJD) is the most common transmissible human subacute spongiform encephalopathy. There is limited literature on CJD in Southeast Asia. We describe the clinical course and diagnostic evaluation of 2 Singapore patients with biopsy-proven CJD. CLINICAL PICTURE Two patients presented with non-specific symptoms such as withdrawal, forgetfulness, asthenia, giddiness and insomnia. Both patients had spontaneous myoclonic jerks and impairment of multiple neurologic systems (visual, pyramidal, cerebellar and neurocognitive systems). Magnetic resonance imaging and electroencephalography provided helpful supportive evidence. Diagnosis of CJD was established on brain biopsy. Histological features included spongioform degeneration, neuronal cell loss and astrocytosis. TREATMENT/OUTCOME Treatment remains palliative. Deterioration in their clinical condition was relentless, progressing to a totally dependent state within 10 to 12 months. CONCLUSION The early features of CJD can be varied and non-specific. It is important for physicians from different specialties to be cognisant of the clinical manifestations of CJD and the appearance of supportive and definitive investigations.
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Affiliation(s)
- S J See
- Department of Neurology (NNI-SGH), Singapore General Hospital, Singapore
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Tan EK, Zhao Y, Puong KY, Law HY, Chan LL, Yew K, Tan C, Shen H, Chandran VR, Teoh ML, Yih Y, Pavanni R, Wong MC, Ng IS. Fragile X premutation alleles in SCA, ET, and parkinsonism in an Asian cohort. Neurology 2004; 63:362-3. [PMID: 15277639 DOI: 10.1212/01.wnl.0000130199.57181.7b] [Citation(s) in RCA: 53] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Abstract
Among 367 subjects, the authors analyzed 167 patients with essential tremor, sporadic progressive cerebellar ataxia, multiple-system atrophy, and atypical parkinsonism and 200 healthy control subjects for FMR1 premutation alleles. None of the subjects carried alleles within the premutation range. These findings suggest that in the absence of other supportive clinical or imaging features, the cost-effectiveness of routine fragile X tremor/ataxia syndrome screening in this Asian cohort with movement disorders was low.
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Affiliation(s)
- E K Tan
- Department of Neurology, Singapore General Hospital, Outram Road, Singapore 169608.
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Wilder-Smith E, Shen Y, Ng YK, Yu GX, Chew NK, Tan CT, Wong MC. Cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy (CADASIL) in a Chinese family: clinical, radiological and skin biopsy features. J Clin Neurosci 2004; 11:304-7. [PMID: 14975424 DOI: 10.1016/j.jocn.2003.05.007] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2003] [Accepted: 05/23/2003] [Indexed: 10/26/2022]
Abstract
We describe the clinical, radiological, genetic and skin biopsy findings of the first Chinese family with cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy (CADASIL). Of the 43-member family tree extending over three generations, eight had typical clinical features of CADASIL with recurrent ischemic stroke. In the three surviving affected family members, brain MRI showed extensive leukoaraiosis. Genotyping revealed heterozygous C to T mutation at nucleotide 406 in exon 3. Unusual clinical features were cerebellar infarction as a presenting complaint and a late age of onset with mild symptoms at age 69. A novel finding is the suggestion of a direct correlation between clinical disease severity and the quantity of ultrastructural pathognomonic granular osmophilic material (GOM) seen on skin biopsy.
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Affiliation(s)
- E Wilder-Smith
- Division of Neurology, National University of Singapore, Singapore.
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Lim WL, Xing H, Wong KH, Wong MC, Shao YM, Ng MH, Lee SS. The lack of epidemiological link between the HIV type 1 infections in Hong Kong and Mainland China. AIDS Res Hum Retroviruses 2004; 20:259-62. [PMID: 15117447 DOI: 10.1089/088922204322996473] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Blood samples were collected from 139 newly reported HIV-1 infections in Hong Kong over a 3-year period between 1999 and 2001, representing 22.8% of all reported cases. A majority of the patients were male (85.6%), Chinese (74%), and adult (97.1%) and acquired HIV-1 through sexual transmission (88.2%). The B and CRF01_AE were the major subtypes detected--49.6% and 44.6%, respectively. Over time, the frequency of CRF01_AE subtype increased, the B subtype decreased, and new subtypes of C (4) 2.8%, B' (1) 0.7%, and CRF07_BC (3) 2.2% emerged. The CRF01_AE subtype was commoner in female, Chinese, heterosexuals, and injection drug users whereas B subtype was commoner in male, white, and people with homosexual/bisexual contacts. There was no common source of infection from the analysis except a discernible cluster of Vietnamese injection drug users with the CRF01_AE subtype. The molecular findings did not suggest an epidemiological link between HIV infection in Hong Kong and Mainland China. Hong Kong's longstanding and extensive methadone treatment network may have contributed to the phenomenon.
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Affiliation(s)
- W L Lim
- Department of Health, Hong Kong Special Administrative Region Government, Hong Kong
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Tan EK, Chai A, Teo YY, Zhao Y, Tan C, Shen H, Chandran VR, Teoh ML, Yih Y, Pavanni R, Wong MC, Puvan K, Lo YL, Yap E. Alpha-synuclein haplotypes implicated in risk of Parkinson's disease. Neurology 2004; 62:128-31. [PMID: 14718715 DOI: 10.1212/01.wnl.0000101721.25345.dc] [Citation(s) in RCA: 66] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Abstract
The authors examined four- and six-loci haplotype constructs (from five single nucleotide polymorphisms and three microsatellite regions) of the alpha-synuclein gene in patients with Parkinson's disease (PD) and controls in an ethnic Chinese population. Logistic regression analysis demonstrated an association of NACP-Rep1 (p = 0.002) and L478 (p < 0.0001) with risk of PD after correction for the effects of age, sex, and the other polymorphic loci. Specific four-loci and six-loci haplotypes were significantly associated with an increased or decreased risk of PD.
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Affiliation(s)
- E K Tan
- Department of Neurology, Singapore General Hospital, Singapore.
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Tan EK, Tan C, Fook-Chong SMC, Lum SY, Chai A, Chung H, Shen H, Zhao Y, Teoh ML, Yih Y, Pavanni R, Chandran VR, Wong MC. Dose-dependent protective effect of coffee, tea, and smoking in Parkinson's disease: a study in ethnic Chinese. J Neurol Sci 2003; 216:163-7. [PMID: 14607318 DOI: 10.1016/j.jns.2003.07.006] [Citation(s) in RCA: 138] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
INTRODUCTION Few studies have examined the relationship of coffee and tea in Parkinson's disease (PD). The potential protective effect of coffee intake and risk of PD has not been studied in a Chinese population. There is a high prevalence of caffeine takers among Chinese in our population. OBJECTIVE We undertook a case control study to examine the relationship between coffee and tea drinking, cigarette smoking, and other enviromental factors and risk of PD among ethnic Chinese in our population. METHODS AND RESULTS 300 PD and 500 population controls were initially screened. Two hundred case control pairs matched for age, gender, and race were finally included in the analysis. Univariate analysis revealed significant association of PD with coffee drinking (p<0.0005), tea drinking (p=0.019), alcohol drinking (p=0.001), cigarette smoking (p<0.0005), and exposure to heavy metals (p=0.006). Conditional logistic regression analysis demonstrated that amount of coffee drunk (OR 0.787, 95%CI 0.664-0.932, p=0.006), amount of tea drunk (OR 0.724, 95%CI 0.559-0.937, p=0.014), number of cigarettes smoked (OR 0.384, 95%CI 0.204-0.722, p=0.003), history of heavy metal and toxin exposure (OR 11.837, 95%CI 1.075-130.366, p=0.044), and heart disease (OR 5.518, 95%CI 1.377-22.116, p=0.016) to be significant factors associated with PD. One unit of coffee and tea (3 cups/day for 10 years) would lead to a 22% and 28% risk reduction of PD. One unit of cigarette smoke (3 packs/day for 10 years) reduced the risk of PD by 62%. CONCLUSIONS We demonstrated a dose-dependent protective effect of PD in coffee and tea drinkers and smokers in an ethnic Chinese population. A history of exposure to heavy metals increased the risk of PD, supporting the multifactorial etiologies of the disease.
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Affiliation(s)
- E-K Tan
- Department of Neurology, Singapore General Hospital, Singapore.
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Wong MC, Nandhra H, Gowrie BJ, Shah EF. A rare presentation of caecal adenocarcinoma. Hospital Medicine 2003; 64:748-9. [PMID: 14702791 DOI: 10.12968/hosp.2003.64.12.2371] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
This paper describes an unusual case of caecal adenocarcinoma which had perforated through to the anterior abdominal wall. Colocutaneous fistula is an uncommon complication of colonic cancer which is more typically associated with sepsis and ischaemia of the bowel, inflammatory bowel disease and trauma. On rare occasions, as in this case, the colocutaneous fistula may be the initial presenting complaint.
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Affiliation(s)
- M C Wong
- Department of General Surgery, Norfolk & Norwich University Hospital, Norwich NR4 7DZ
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Wilder-Smith E, Tan EK, Law HY, Zhao Y, Ng I, Wong MC. Spinocerebellar ataxia type 3 presenting as an L-DOPA responsive dystonia phenotype in a Chinese family. J Neurol Sci 2003; 213:25-8. [PMID: 12873751 DOI: 10.1016/s0022-510x(03)00129-1] [Citation(s) in RCA: 50] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
The clinical spectrum of spinocerebellar ataxia 3 (SCA 3) disease is wide and varied. We describe a Chinese patient with a mutation at the SCA 3 locus with clinical features of levodopa-responsive dystonia. The family history was suggestive of being autosomally dominant. Levodopa responsiveness though rare has been described in families with features of parkinsonism. Noteworthy is the relatively late onset of disease (>40 years) possibly explained by the low number of affected alleles at 59, the usual range being from 62 to 86, with the lowest recorded number at 56. This expands the wide and varied phenotypic manifestations of SCA 3, and highlights the observation that features suggestive of levodopa-responsive dystonia (DRD) such as focal dystonia, gait difficulty with diurnal fluctuation of symptoms, and a marked response to low doses of levodopa can be presenting features of SCA 3. SCA 3 should be considered a differential diagnosis in adult patients who present with DRD phenotype and with a positive family history.
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Affiliation(s)
- E Wilder-Smith
- Division of Neurology, National University Hospital, 5 Lower Kent Ridge Road, Singapore 119074, Republic of Singapore.
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Affiliation(s)
- E K Tan
- Department of Neurology, Singapore General Hospital, Singapore, Singapore.
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Tan EK, Chai A, Lum SY, Shen H, Tan C, Teoh ML, Yih Y, Wong MC, Zhao Y. Monoamine oxidase B polymorphism, cigarette smoking and risk of Parkinson's disease: a study in an Asian population. Am J Med Genet B Neuropsychiatr Genet 2003; 120B:58-62. [PMID: 12815741 DOI: 10.1002/ajmg.b.20035] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Cigarette smoking is associated with reduced monoamine oxidase B (MAO B) activity. Polymorphisms of the MAO B gene may modify the relationship between smoking and Parkinson's Disease (PD). We examined the association of MAO B intron 13 G/A polymorphism and risk of PD, and the modulation of the polymorphism on smoking and PD in an Asian study population in Singapore. Two hundred and thirty PD patients (mean age 66.0 +/- 9.4 years, 63% men) and 241 age, gender, and race matched controls (mean age 64 +/- 9.2 years, 58.9% males) were studied. The frequency of G and A alleles in PD and controls was; 66/315 (21.0%) vs. 73/340 (21.5%) and 249/315 (79.0%) vs. 267/340 (78.5%). For women, the genotype frequency in PD and controls was; GG: 7/85 (8.2%) vs. 8/99 (8.1%); GA: 25/85 (29.4%) vs. 27/99 (27.3%); AA: 53/85 (62.4%) vs. 64/99 (64.6%). For men, allele frequency in PD and controls was; A: 118/145 (81.4%) vs. 112/142 (78.9%) and G: 27/145 (18.6%) vs. 30/142 (21.1%). The allele and genotype frequencies were not significantly different between young and late onset PD. The frequency of "ever" smokers in PD and controls was 31/230 (13.5%) vs. 52/241 (21.6%), P = 0.02. A stepwise logistic regression analysis did not reveal any interaction of smoking and the G allele and risk of PD. The MAO B G/A genotype frequency in our Asian population was quite different from Caucasians suggesting that ethnicity specific effects need to be considered in evaluating gene-environmental interaction.
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Affiliation(s)
- E K Tan
- Department of Neurology, Singapore General Hospital, Singapore.
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Abstract
Levodopa-induced dyskinesias have been reported in Parkinson's disease and multiple system atrophy. Cranial dystonias are rare in patients with progressive supranuclear palsy (PSP). In this report we describe an unusual case of reversible levodopa-induced Oromandibular dystonia (OMD) in a PSP patient to highlight the importance of recognizing this drug related complication in the management of PSP, and discuss the possible underlying pathophysiology.
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Affiliation(s)
- E K Tan
- Department of Neurology, Singapore General Hospital, Outram Road, Singapore 169608, Singapore.
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Abstract
INTRODUCTION Clinicians switch from one dopamine agonist to another for various reasons. However, each change may inadvertently result in certain potential risks such as decreased medication efficacy or new side-effects. OBJECTIVE We evaluated the tolerability of a switch of bromocriptine to piribedil using two conversion ratios as a primary outcome measure, with motor function as a secondary outcome measure, in patients with mild to moderate Parkinson's disease (PD). METHODS Twenty consecutive patients with mild to moderate PD (Hoehn and Yahr, stage II-III) on treatment with stable doses of bromocriptine and levodopa were randomized to two groups of 10 patients each, to receive piribedil based on 1:5 or 1:10 conversion ratios. Blinded evaluations were performed: 1) United Parkinson's Diseased Rating Scale (UPDRS) scores both in 'on' and 'off', 2) Open-ended interviews for adverse events, 3) Epworth Sleepiness Scale, 4) Purdue Pegboard assessment during 'on' and 'off', 5) Hand-arm movement test during 'on' and 'off', and 6) Walking test during 'on' and 'off'. RESULTS Major adverse events included 'sleep attacks' in one patient and minor side-effects included giddiness, nausea, hallucinations, sleepiness and lethargy. However, these were mild and 19 (95%) of the 20 patients completed the study. There was a significant improvement in both the UPDRS 'off' total and motor scores at 1 month compared with baseline for the group on 1:10 ratio. The walking times during the 'off' state at 1 and 2 months were significantly better compared with baseline in the 1:5 group. There were otherwise no significant differences in the rating tests during both 'off' and 'on' states before and after the bromocriptine switch. CONCLUSIONS We demonstrated that patients with mild to moderate PD who were on relatively low doses of bromocriptine can be safely switched to piribedil based on a conversion ratio of either 1:5 or 1:10. However, the higher conversion ratio has to be carried out with caution in patients with daytime somnolence.
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Affiliation(s)
- E K Tan
- Department of Neurology, Singapore General Hospital, National Neuroscience Institute Sing Health, Singapore
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Affiliation(s)
- E K Tan
- Department of Neurology, Diagnostic Radiology, Singapore General Hospital, Singapore 169608, Republic of Singapore.
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Abstract
We report the prevalence and ethnic differences of autosomal-dominant cerebellar ataxia (ADCA) in Singapore. Amongst 204 patients with ataxia who underwent genetic testing for dentatorubral-pallidoluysian atrophy (DRPLA) and for spinocerebellar ataxias (SCA) 1, 2, 3, 6, 7, 8, 10 and 12, 58 (28.4%) patients from 36 families tested positive. SCA 3 was identified in 31 (53.4%) patients from 15 families, SCA 2 in 17 (29.3%) patients from 12 families and SCA 1 in four (6.9%) patients from four families. Other SCA subtypes were rare. SCA 2 was the only subtype identified amongst ethnic Malay and ethnic Indian families. The estimated prevalence of ADCA in Singaporean families was at least 1 : 27,000. Based on the history and ancestry of Singaporeans, our study supported a founder effect for specific SCA subtypes and the association of ethnicity-specific SCA subtypes. Our findings suggest that SCA 2 is relatively common amongst the Malay race and that priority testing for SCA 3 and SCA 2 for ethnic Chinese, and SCA 2 for ethnic Malay, may be cost effective and relevant for the region.
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Affiliation(s)
- Y Zhao
- Department of Clinical Research, Singapore General Hospital, Singapore.
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Abstract
Extrapontine (EPM) and central pontine myelinolysis (CPM) are rare and frequently related to rapid correction of hyponatremia. We describe a 60-year-old woman who developed an unusual evolving spectrum of movement disorders secondary to EPM and CPM following intravenous sodium replacement therapy for severe hyponatremia. She presented initially with confusion, generalized coarse postural limb tremor, myoclonic jerks and quadriparesis. Subsequently her mental state improved and her tremor and weakness resolved. Over the following months, she developed progressive painful dystonia of her facial musculature and lower limbs. This gradually became generalized and associated with choreoathethosis in her limbs. In addition, she had increasing bradykinesia and rigidity, which responded poorly to levodopa treatment. Our case illustrates that while the myelin destruction occurs during the initial insult of the osmotic demyelinating process, its delayed clinical effects resulting from ineffective reorganization of neuronal structures may be progressive, evolve with time, and difficult to treat.
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Affiliation(s)
- A B H Seah
- Department of Neurology, Singapore General Hospital, Outram Road, Singapore
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Abstract
A 29-year-old man with cutis laxa presented requesting surgery to improve his appearance. The patient had an unaffected identical twin brother which allowed us to compare how he had changed over the years in relation to his sibling and this also provided us with a gold standard for any surgery performed. The patient underwent staged surgery including upper lid blepharoplasties and two facelifts.
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Tan EK, Chai A, Zhao Y, Lum SY, Fook-Chong SMC, Teoh ML, Yih Y, Pavanni R, Wong MC. Mitochondrial complex I polymorphism and cigarette smoking in Parkinson's disease. Neurology 2002; 59:1288-9. [PMID: 12391372 DOI: 10.1212/01.wnl.0000031809.71668.a1] [Citation(s) in RCA: 20] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Affiliation(s)
- E K Tan
- Department of Neurology, Singapore General Hospital, Singapore.
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