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Hwong WY, Ng SW, Tong SF, Ab Rahman N, Law WC, Wong SK, Puvanarajah SD, Mohd Norzi A, Lian FS, Sivasampu S. Identifying factors in the provision of intravenous stroke thrombolysis in Malaysia: a multiple case study from the healthcare providers' perspective. BMC Health Serv Res 2024; 24:34. [PMID: 38183003 PMCID: PMC10768456 DOI: 10.1186/s12913-023-10397-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2023] [Accepted: 11/29/2023] [Indexed: 01/07/2024] Open
Abstract
BACKGROUND Translation into clinical practice for use of intravenous thrombolysis (IVT) for the management of ischemic stroke remains a challenge especially across low- and middle-income countries, with regional inconsistencies in its rate. This study aimed at identifying factors that influenced the provision of IVT and the variation in its rates in Malaysia. METHODS A multiple case study underpinning the Tailored Implementation for Chronic Diseases framework was carried out in three public hospitals with differing rates of IVT using a multiple method design. Twenty-five in-depth interviews and 12 focus groups discussions were conducted among 89 healthcare providers, along with a survey on hospital resources and a medical records review to identify reasons for not receiving IVT. Qualitative data were analysed using reflective thematic method, before triangulated with quantitative findings. RESULTS Of five factors identified, three factors that distinctively influenced the variation of IVT across the hospitals were: 1) leadership through quality stroke champions, 2) team cohesiveness which entailed team dynamics and its degree of alignment and, 3) facilitative work process which included workflow simplification and familiarity with IVT. Two other factors that were consistently identified as barriers in these hospitals included patient factors which largely encompassed delayed presentation, and resource constraints. About 50.0 - 67.6% of ischemic stroke patients missed the opportunity to receive IVT due to delayed presentation. CONCLUSIONS In addition to the global effort to explore sustainable measures to improve patients' emergency response for stroke, attempts to improve the provision of IVT for stroke care should also consider the inclusion of interventions targeting on health systems perspectives such as promoting quality leadership, team cohesiveness and workflow optimisation.
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Affiliation(s)
- Wen Yea Hwong
- Institute for Clinical Research, National Institutes of Health, Ministry of Health Malaysia, Shah Alam, Selangor, Malaysia.
- Julius Center for Health Sciences and Primary Care, University Medical Center Utrecht, Utrecht University, Utrecht, the Netherlands.
| | - Sock Wen Ng
- Institute for Clinical Research, National Institutes of Health, Ministry of Health Malaysia, Shah Alam, Selangor, Malaysia
| | - Seng Fah Tong
- Department of Family Medicine, Universiti Kebangsaan Malaysia, Kuala Lumpur, Malaysia
| | - Norazida Ab Rahman
- Institute for Clinical Research, National Institutes of Health, Ministry of Health Malaysia, Shah Alam, Selangor, Malaysia
| | - Wan Chung Law
- Neurology Unit, Department of Medicine, Sarawak General Hospital, Ministry of Health Malaysia, Kuching, Sarawak, Malaysia
| | - Sing Keat Wong
- Department of Neurology, Hospital Kuala Lumpur, Ministry of Health Malaysia, Kuala Lumpur, Malaysia
| | - Santhi Datuk Puvanarajah
- Department of Neurology, Hospital Kuala Lumpur, Ministry of Health Malaysia, Kuala Lumpur, Malaysia
| | - Aisyah Mohd Norzi
- Institute for Clinical Research, National Institutes of Health, Ministry of Health Malaysia, Shah Alam, Selangor, Malaysia
| | - Fiona Suling Lian
- Clinical Research Centre, Penang General Hospital, Ministry of Health Malaysia, Penang, Malaysia
| | - Sheamini Sivasampu
- Institute for Clinical Research, National Institutes of Health, Ministry of Health Malaysia, Shah Alam, Selangor, Malaysia
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Hwong WY, Ng SW, Tong SF, Ab Rahman N, Law WC, Kaman Z, Wong SK, Puvanarajah SD, Sivasampu S. Stroke thrombolysis in a middle-income country: A case study exploring the determinants of its implementation. Front Neurol 2022; 13:1048807. [PMID: 36504666 PMCID: PMC9729841 DOI: 10.3389/fneur.2022.1048807] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2022] [Accepted: 11/07/2022] [Indexed: 11/25/2022] Open
Abstract
Introduction Translation of evidence into clinical practice for use of intravenous thrombolysis in acute stroke care has been slow, especially across low- and middle-income countries. In Malaysia where the average national uptake was poor among the public hospitals in 2018, one hospital intriguingly showed comparable thrombolysis rates to high-income countries. This study aimed to explore and provide in-depth understanding of factors and explanations for the high rates of intravenous stroke thrombolysis in this hospital. Methods This single case study sourced data using a multimethod approach: (1) semi-structured in-depth interviews and focus group discussions, (2) surveys, and (3) review of medical records. The Tailored Implementation of Chronic Diseases (TICD) framework was used as a guide to understand the determinants of implementation. Twenty-nine participants comprising the Hospital Director, neurologists, emergency physicians, radiologists, pharmacists, nurses and medical assistants (MAs) were included. Thematic analyses were conducted inductively before triangulated with quantitative analyses and document reviews. Results Favorable factors contributing to the uptake included: (1) cohesiveness of team members which comprised of positive interprofessional team dynamics, shared personal beliefs and values, and passionate leadership, and (2) facilitative work process through simplification of workflow and understanding the rationale of the sense of urgency. Patient factors was a limiting factor. Almost two third of ischemic stroke patients arrived at the hospital outside the therapeutic window time, attributing patients' delayed presentation as a main barrier to the uptake of intravenous stroke thrombolysis. One other barrier was the availability of resources, although this was innovatively optimized to minimize its impact on the uptake of the therapy. As such, potential in-hospital delays accounted for only 3.8% of patients who missed the opportunity to receive thrombolysis. Conclusions Despite the ongoing challenges, the success in implementing intravenous stroke thrombolysis as standard of care was attributed to the cohesiveness of team members and having facilitative work processes. For countries of similar settings, plans to improve the uptake of intravenous stroke thrombolysis should consider the inclusion of interventions targeting on these modifiable factors.
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Affiliation(s)
- Wen Yea Hwong
- Institute for Clinical Research, National Institutes of Health, Ministry of Health Malaysia, Selangor, Malaysia,Julius Center for Health Sciences and Primary Care, University Medical Center Utrecht, Utrecht University, Utrecht, Netherlands,*Correspondence: Wen Yea Hwong ;
| | - Sock Wen Ng
- Institute for Clinical Research, National Institutes of Health, Ministry of Health Malaysia, Selangor, Malaysia
| | - Seng Fah Tong
- Department of Family Medicine, Universiti Kebangsaan Malaysia, Selangor, Malaysia
| | - Norazida Ab Rahman
- Institute for Clinical Research, National Institutes of Health, Ministry of Health Malaysia, Selangor, Malaysia
| | - Wan Chung Law
- Neurology Unit, Department of Medicine, Sarawak General Hospital, Ministry of Health Malaysia, Kuching, Malaysia
| | - Zurainah Kaman
- Neurology Unit, Department of Medicine, Sarawak General Hospital, Ministry of Health Malaysia, Kuching, Malaysia
| | - Sing Keat Wong
- Department of Neurology, Hospital Kuala Lumpur, Ministry of Health Malaysia, Kuala Lumpur, Malaysia
| | - Santhi Datuk Puvanarajah
- Department of Neurology, Hospital Kuala Lumpur, Ministry of Health Malaysia, Kuala Lumpur, Malaysia
| | - Sheamini Sivasampu
- Institute for Clinical Research, National Institutes of Health, Ministry of Health Malaysia, Selangor, Malaysia
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Hiew FL, Thit WM, Alexander M, Thirugnanam U, Siritho S, Tan K, Mya Aye SM, Ohnmar O, Estiasari R, Yassin N, Pasco PM, Keosodsay SS, Trong Nghia HT, Islam MDB, Wong SK, Lee S, Chhabra A, Viswanathan S. Consensus recommendation on the use of therapeutic plasma exchange for adult neurological diseases in Southeast Asia from the Southeast Asia therapeutic plasma exchange consortium. J Cent Nerv Syst Dis 2022; 13:11795735211057314. [PMID: 35173510 PMCID: PMC8842418 DOI: 10.1177/11795735211057314] [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] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2021] [Accepted: 10/12/2021] [Indexed: 11/30/2022] Open
Abstract
Therapeutic plasma exchange (TPE) is an effective and affordable treatment option in most parts of Southeast Asia (SEA). In 2018, the SEA TPE Consortium (SEATPEC) was established, consisting of regional neurologists working to improve outcome of various autoimmune neurological diseases. We proposed an immunotherapeutic guideline prioritizing TPE for this region. We reviewed disease burden, evidence-based treatment options, and major guidelines for common autoimmune neurological disorders seen in SEA. A modified treatment algorithm based on consensus agreement by key-opinion leaders was proposed. Autoimmune antibody diagnostic testing through collaboration with accredited laboratories was established. Choice of first-line immunotherapies (IVIg/corticosteroid/TPE) is based on available evidence, clinicians’ experience, contraindications, local availability, and affordability. TPE could be chosen as first-line therapy for GBS, CIDP, MG (acute/short term), IgG, A paraproteinemic neuropathy, and NMDAR encephalitis. Treatment is stopped for acute monophasic conditions such as GBS and ADEM following satisfactory outcome. For chronic immune disorders, a therapy taper or long-term maintenance therapy is recommended depending on the defined clinical state. TPE as second-line treatment is indicated for IVIg or corticosteroids refractory cases of ADEM, NMOSD (acute), MG, and NMDAR/LGI1/CASPR2/Hashimoto’s encephalitis. With better diagnosis, treatment initiation with TPE is a sustainable and effective immunotherapy for autoimmune neurological diseases in SEA.
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Affiliation(s)
- Fu Liong Hiew
- Department of Neurology, Kuala Lumpur Hospital, Kuala Lumpur, Malaysia
- Dr Fu Liong Hiew, Physician and Neurologist, Department of Neurology, Kuala Lumpur Hospital, Kuala Lumpur, Malaysia Jalan Pahang, Wilayah Persekutuan Kuala Lumpur 50586, Malaysia.
| | - Win Min Thit
- University of Medicine 1, Yangon, Myanmar
- Yangon General Hospital/University of Medicine 1, Yangon, Myanmar
| | - Mathew Alexander
- Brunei Neuroscience Stroke and Rehabilitation Centre, Pantai Jerudong Specialist Centre, Brunei Darussalam
| | | | - Sasitorn Siritho
- Division of Neurology, Faculty of Medicine, Siriraj Hospital, Bumrungrad International Hospital, Bangkok, Thailand
| | - Kevin Tan
- Department of Neurology, National Neuroscience Institute, Singapore, Singapore
| | | | - Ohnmar Ohnmar
- University of Medicine 1, Yangon, Myanmar
- Yangon General Hospital/University of Medicine 1, Yangon, Myanmar
| | - Riwanti Estiasari
- Department of Neurology, Cipto Mangunkusumo Hospital/Faculty of Medicine Universitas Indonesia, Jakarta, Indonesia
| | | | | | | | | | - MD Badrul Islam
- Laboratory Sciences and Services Division (LSSD), The International Centre for Diarrhoeal Disease, Dhaka, Bangladesh
| | - Sing Keat Wong
- Department of Neurology, Kuala Lumpur Hospital, Kuala Lumpur, Malaysia
| | - Shirley Lee
- Department of Neurology, Kuala Lumpur Hospital, Kuala Lumpur, Malaysia
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Bahar-Moni AS, Wong SK, Mohd-Shariff N, Sapuan J, Abdullah S. A Review of Surgically Treated Distal Radius Fractures in a University Hospital. Malays Orthop J 2021; 15:52-57. [PMID: 34966495 PMCID: PMC8667247 DOI: 10.5704/moj.2111.008] [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] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2020] [Accepted: 07/19/2021] [Indexed: 11/09/2022] Open
Abstract
Introduction: Distal radius fracture (DRF) is the most common orthopaedic injury with a reported incidence of 17.5%. It is commonly seen in young males and elderly females. Over the last two decades, there is an increasing tendency to treat DRF surgically by open reduction and internal fixation (ORIF) with plate and screws owing to improved device design, better fixation and operative technique. The purpose of this study was to evaluate the demographic characteristics, type and method of fixation, and outcome in all surgically treated DRF cases from 2014 to 2018 in a university hospital. Materials and methods: A retrospective review of all surgically treated DRF cases with one year follow-up in a tertiary hospital in Malaysia was done. Patients who left the follow-up clinic before one-year post-surgery or before fracture union were excluded. A total of 82 patients with 88 DRF were finally included into the study and outcome in terms of union time and need of multiple surgeries were analysed along with the predictors. Results: In this study, mean age of the patient was 46.2 years. Motor vehicle accident was the commonest cause of the fracture and AO Type C fracture was the commonest fracture type. Seventeen (19.3%) out of 88 fractures were compound fracture. Open reduction and internal fixation with volar plate was the most common surgical technique done in this series (93.2%). Three (3.5%) out of 88 fractures required multiple surgeries and eighty-three (94.3%) DRF cases were united before nine months of the surgery in this study. There was statistically significant association between clinical type of the fracture and the union time (p-value <0.05). Conclusion: There was a 1.7:1 male-female ratio with AO-C fracture being the most common type of fracture. The most common method of fixation was ORIF with volar locked plate. Patients with closed fractures have a higher rate of union compared to open fractures at nine months.
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Affiliation(s)
- A S Bahar-Moni
- Department of Orthopaedic Surgery, Universiti Sains Malaysia, Kepala Batas, Malaysia
| | - S K Wong
- Department of Orthopaedics and Traumatology, Universiti Kebangsaan Malaysia, Kuala Lumpur, Malaysia
| | - N Mohd-Shariff
- Life Style Cluster, Universiti Sains Malaysia, Kepala Batas, Malaysia
| | - J Sapuan
- Department of Orthopaedics and Traumatology, Universiti Kebangsaan Malaysia, Kuala Lumpur, Malaysia
| | - S Abdullah
- Department of Orthopaedics and Traumatology, Universiti Kebangsaan Malaysia, Kuala Lumpur, Malaysia
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Wong SK, Tse KH, Pan NY. Young Adult Hip Dysplasia: An Important and Under-recognised Clinical Cause of Hip Pain on Plain Radiographs. Hong Kong Journal of Radiology 2020. [DOI: 10.12809/hkjr2016979] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022] Open
Affiliation(s)
- SK Wong
- Department of Radiology, Princess Margaret Hospital, Laichikok, Hong Kong
| | - KH Tse
- Department of Radiology, Princess Margaret Hospital, Laichikok, Hong Kong
| | - NY Pan
- Department of Radiology, Princess Margaret Hospital, Laichikok, Hong Kong
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Pender A, Dunne EM, Wong SK, Ho C, Melosky B. Canadian Lung Cancer Conference 2019. Curr Oncol 2019; 26:e578-e580. [PMID: 31548828 DOI: 10.3747/co.26.5105] [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] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Abstract
The 19th Canadian Lung Cancer Conference took place 7-8 February 2019 in Vancouver, British Columbia. This annual interdisciplinary education event attracted participants from throughout Canada to review the latest advances in lung cancer care and to learn from world-renowned experts in the field. The highlights of this year's conference were perspectives about biomarkers for immunotherapy, approaches to oligoprogressive disease, and caregiver burnout.
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Affiliation(s)
- A Pender
- Medical Oncology, BC Cancer, Vancouver, BC
| | - E M Dunne
- Radiation Oncology, BC Cancer, Vancouver, BC
| | - S K Wong
- Medical Oncology, BC Cancer, Vancouver, BC
| | - C Ho
- Medical Oncology, BC Cancer, Vancouver, BC
| | - B Melosky
- Medical Oncology, BC Cancer, Vancouver, BC
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Mitchell I, Wong SK, Paes B, Ruff M, Bjornson C, Li A, Lanctôt KL. Respiratory syncytial virus prophylaxis in cystic fibrosis: the Canadian registry of palivizumab data (2005-2016). Eur J Clin Microbiol Infect Dis 2018; 37:1345-1352. [PMID: 29728782 DOI: 10.1007/s10096-018-3256-0] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2018] [Accepted: 04/09/2018] [Indexed: 02/06/2023]
Abstract
Respiratory syncytial virus (RSV) may cause severe illness in cystic fibrosis (CF) children, but recommendations vary on prophylaxis. CARESS is a prospective registry of children who received palivizumab in 32 Canadian sites from 2005 to 2016. Demographic data were collected at enrollment and respiratory illness-related events recorded monthly. We reviewed respiratory illness hospitalization (RIH) and RSV hospitalization (RSVH) in CF children aged < 24 months versus those prophylaxed for standard indications (SI; prematurity, chronic lung disease [CLD] and congenital heart disease [CHD]), and complex medical disorders (CM). Of 23,228 children analyzed, 19,452 (83.8%) were SI, 3349 (14.4%) were CM, and 427 (1.8%) were CF. CF children were more likely to be Caucasian, heavier at birth and enrollment, and less likely to have a sibling or live in crowded conditions. CF children were similar to the other groups in daycare attendance, history of atopy, and exposure to smoking. RIH incidences were 4.3% (premature), 13.8% CLD, 11.5% CHD, 11.7% CM, and 6.8% CF. RSVH incidence in CF children was similar to that in the SI and CM groups: 1.1, 1.5, and 2.0% groups respectively. Cox regression analyses showed that compared to CF children, the HRs for RSVH in SI (HR 2.0 95% CI 0.5-8.3, p = 0.3) and CM (HR 2.4, 95% CI 0.6-9.8, p = 0.2) did not differ. CF children are equally at risk for RSVH relative to those prophylaxed for other indications. Pending robust evidence from prospective trials, palivizumab could perhaps be considered in the interim, for young CF patients born early during the RSV season with evidence of serious lung disease.
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Affiliation(s)
- Ian Mitchell
- Department of Pediatrics, Alberta Children's Hospital, University of Calgary, 2888 Shaganappi Trail NW, Calgary, Alberta, T3B 6A8, Canada.
| | - S K Wong
- Medical Outcomes and Research in Economics (MORE®) Research Group, Sunnybrook Health Sciences Centre, University of Toronto, 2075 Bayview Avenue, Room FG-08, Toronto, Ontario, M4N3M5, Canada
| | - B Paes
- Department of Pediatrics, McMaster University, Room - HSC-3A, 1280 Main Street West, Hamilton, Ontario, L8S 4K1, Canada
| | - M Ruff
- Department of Pediatrics, Alberta Children's Hospital, University of Calgary, 2888 Shaganappi Trail NW, Calgary, Alberta, T3B 6A8, Canada
| | - C Bjornson
- Department of Pediatrics, Alberta Children's Hospital, University of Calgary, 2888 Shaganappi Trail NW, Calgary, Alberta, T3B 6A8, Canada
| | - A Li
- Medical Outcomes and Research in Economics (MORE®) Research Group, Sunnybrook Health Sciences Centre, University of Toronto, 2075 Bayview Avenue, Room FG-08, Toronto, Ontario, M4N3M5, Canada
| | - K L Lanctôt
- Medical Outcomes and Research in Economics (MORE®) Research Group, Sunnybrook Health Sciences Centre, University of Toronto, 2075 Bayview Avenue, Room FG-08, Toronto, Ontario, M4N3M5, Canada
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Abstract
This is a retrospective study to analyze the pattern of drug overdose in teenagers. Between 1/7/98 to 30/6/01, there were 100 patients between the age of 13 to 19 attending Alice Ho Miu Ling Nethersole Hospital emergency department for drug overdose. Eighty-three cases were included for analysis. The majority was female (71 cases, 86%). The most frequent drugs were panadol and drugs for treatment of flu (43%), sleeping pills (18%), diazepam (18%). Panadol, drugs for treatment of flu and sleeping pills were usually bought over the counter. Diazepam was obtained from friends or bought in China. The common reasons for drug overdose were “unhappy boyfriend/girlfriend relationship” (40%), “unhappy relationship with family” (25%), “unhappiness at school” (14%). Thirty-one percent of cases had suicidal ideas. Many of them had poor family relationships, poor school performance or were unemployed.
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Chuang XL, Ooi CC, Chin ST, Png MA, Wong SK, Tay SC, McGrouther DA. What triggers in trigger finger? The flexor tendons at the flexor digitorum superficialis bifurcation. J Plast Reconstr Aesthet Surg 2017; 70:1411-1419. [PMID: 28709917 DOI: 10.1016/j.bjps.2017.05.037] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2017] [Revised: 05/16/2017] [Accepted: 05/17/2017] [Indexed: 11/26/2022]
Abstract
To define the role of the flexor tendons in trigger finger, a high-resolution ultrasound examination was performed in 20 trigger fingers and 20 normal contralateral digits in three digital postures: full extension, mid-flexion and near-full flexion. Precise measurements of diameter and cross-sectional area of the combined tendon mass were recorded at five clearly defined locations: summit of the metacarpal head, proximal lip of the proximal phalanx (PP) and at 1/8, 1/4 and 1/2 length of the PP. In the normal tendons, there was an anatomical thickening, not previously appreciated at 1/4 length PP, in the region of the FDS bifurcation. This anatomical region moved proximally on finger flexion to the A1 pulley. In trigger fingers, the flexor tendons had greater diameter (sagittal view) and cross-sectional area than the normal side at all locations (p < 0.01, p < 0.001), with an even greater increase in diameter in the FDS bifurcation area (p < 0.001). Trigger fingers also had thicker A1 pulleys (p < 0.001). Triggering occurs on flexing the finger when the enlarged combined flexor tendon mass at the specific anatomical region of the FDS bifurcation impacts on the thickened A1 pulley, resisting its excursion.
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Affiliation(s)
| | - C C Ooi
- Department of Diagnostic Radiology, Singapore General Hospital, Singapore
| | - S T Chin
- Biomechanics Laboratory, Academia, Singapore
| | - M A Png
- Duke-NUS Medical School, Singapore; Department of Radiology, Singapore General Hospital, Singapore
| | - S K Wong
- Duke-NUS Medical School, Singapore; Department of Radiology, Singapore General Hospital, Singapore
| | - S C Tay
- Duke-NUS Medical School, Singapore; Biomechanics Laboratory, Academia, Singapore; Department of Hand Surgery, Singapore General Hospital, Singapore
| | - D A McGrouther
- Duke-NUS Medical School, Singapore; Department of Hand Surgery, Singapore General Hospital, Singapore.
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Wong HS, He SK, Chung HJ, Zhang MS, Cher K, Low M, Zhou TJ, Yang Y, Wong SK. Reduction of magnetic damping and isotropic coercivity and increase of saturation magnetization in Rh-incorporated CoIr system. Nanotechnology 2016; 27:455705. [PMID: 27713181 DOI: 10.1088/0957-4484/27/45/455705] [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] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
Replacing Ir with Rh in a CoIr system possessing negative uniaxial magnetocrystalline anisotropy (K u ) substantially reduces its magnetic damping and coercivity by more than half while retaining its high negative K u . Moreover, a higher saturation magnetization (M s ) and more isotropic coercivity are achieved. Such material development makes it particularly suitable for use as the soft underlayer (SUL) of magnetic recording media for reducing noise, and as the oscillation layer of a spin-torque oscillator (STO) for achieving higher oscillation frequency, larger AC magnetic field and lower driving current, which can be readily integrated with the current recording head for microwave-assisted magnetic recording. Finally, we recommend a composite free layer by coupling CoIr with a spin polarizer (Co or Co/Cu/Co) for the enhancement of the spin-polarization rate and, therefore, the improvement of STO efficiency. These could pave the way for CoIr-based materials to be implemented in devices requiring a negative Ku with low damping and high 'softness', such as oscillators.
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Affiliation(s)
- H S Wong
- Data Storage Institute, A*STAR (Agency for Science, Technology and Research), 2 Fusionopolis Way, #08-01 Innovis, Singapore 138634
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Liu SY, Chu CM, Kong AP, Wong SK, Chiu PW, Chow FC, Ng EK. Radiofrequency ablation compared with laparoscopic adrenalectomy for aldosterone-producing adenoma. Br J Surg 2016; 103:1476-86. [PMID: 27511444 DOI: 10.1002/bjs.10219] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2016] [Revised: 03/27/2016] [Accepted: 04/25/2016] [Indexed: 12/30/2022]
Abstract
BACKGROUND Radiofrequency ablation (RFA) is an emerging treatment for primary aldosteronism owing to aldosterone-producing adenoma. Whether RFA could be an alternative treatment to laparoscopic adrenalectomy is unknown. METHODS This was a retrospective comparative study in patients with aldosterone-producing adenoma undergoing either laparoscopic adrenalectomy or CT-guided percutaneous RFA between 2004 and 2012. Short-term outcomes and long-term resolution rates of primary aldosteronism (normalized aldosterone to renin ratio), hypokalaemia and hypertension (BP lower than 140/90 mmHg without antihypertensive medical therapy) were evaluated. RESULTS Some 63 patients were included, 27 in the laparoscopic adrenalectomy group and 36 in the RFA group. RFA was associated with shorter duration of operation (median 12 versus 124 min; P < 0·001), shorter hospital stay (2 versus 4 days; P < 0·001), lower analgesic requirements (13 of 36 versus 23 of 27 patients; P < 0·001) and earlier resumption of work (median 4 versus 14 days; P = 0·006). Morbidity rates were similar in the two groups. With median follow-up of 5·7 (range 1·9-10·6) years, resolution of primary aldosteronism was seen in 33 of 36 patients treated with RFA and all 27 patients who had laparoscopic adrenalectomy (P = 0·180). Hypertension was resolved less frequently after treatment with RFA compared with laparoscopic adrenalectomy (13 of 36 versus 19 of 27 patients; P = 0·007). Hypokalaemia was resolved in all patients. CONCLUSION For patients with aldosterone-producing adenoma the efficacy of resolution of primary aldosteronism and hypertension was inferior after treatment with RFA compared with laparoscopic adrenalectomy.
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Affiliation(s)
- S Y Liu
- Departments of Surgery, Prince of Wales Hospital, Faculty of Medicine, Chinese University of Hong Kong, Shatin, Hong Kong, China
| | - C M Chu
- Departments of Diagnostic Radiology and Organ Imaging, Prince of Wales Hospital, Faculty of Medicine, Chinese University of Hong Kong, Shatin, Hong Kong, China
| | - A P Kong
- Departments of Medicine and Therapeutics, Prince of Wales Hospital, Faculty of Medicine, Chinese University of Hong Kong, Shatin, Hong Kong, China
| | - S K Wong
- Departments of Surgery, Prince of Wales Hospital, Faculty of Medicine, Chinese University of Hong Kong, Shatin, Hong Kong, China
| | - P W Chiu
- Departments of Surgery, Prince of Wales Hospital, Faculty of Medicine, Chinese University of Hong Kong, Shatin, Hong Kong, China
| | - F C Chow
- Departments of Medicine and Therapeutics, Prince of Wales Hospital, Faculty of Medicine, Chinese University of Hong Kong, Shatin, Hong Kong, China
| | - E K Ng
- Departments of Surgery, Prince of Wales Hospital, Faculty of Medicine, Chinese University of Hong Kong, Shatin, Hong Kong, China.
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Bernitsky DA, Stark WJ, McCartney DL, Wong SK, Maumenee AE. Current concepts in intraocular lens implantation. Dev Ophthalmol 2015; 14:146-51. [PMID: 3498656 DOI: 10.1159/000414382] [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: 01/06/2023]
Abstract
PC IOLs appear to be safe and effective and there are few contraindications. Based on the available data we feel confident about implanting PC IOLs in healthy eyes of patients aged 40 or older. For younger patients, we do not recommended an IOL unless glasses or contact lens use is not feasible. Caution is urged however in the use of semiflexible, closed-loop AC IOLs as well as 'soft' PC IOLs. Other questions regarding material of choice, bag versus sulcus fixation, and UV absorbers remain controversial.
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Affiliation(s)
- D A Bernitsky
- Wilmer Ophthalmological Institute, Johns Hopkins Hospital, Baltimore, Md
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Ng CG, Wong SK, Loh HS, Yee A. Anhedonia among patients with Major Depressive Disorder: A comparison between patients on escitalopram and healthy controls. Clin Ter 2014; 165:e384-90. [PMID: 25524191 DOI: 10.7417/ct.2014.1778] [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] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
BACKGROUND AND AIMS Escitalopram has widely been recognized as one of the most frequently used antidepressants, with superior tolerability and great efficacy in preventing major depressive disorder (MDD) relapse and recurrence. However, anhedonia, which is a core symptom of MDD, remains difficult to treat. This study investigates the hedonic levels of MDD patients treated with Escitalopram. MATERIALS AND METHODS A total of 108 participants, 26 of whom with MDD on Escitalopram, were recruited in this cross sectional study. They were evaluated using the Snaith-Hamilton Pleasure Scale (SHAPS) and Beck Depression Inventory (BDI) questionnaires to assess their hedonic state, general mental health condition and level of depression. RESULTS Our study shows that most items in the SHAPS scores are significantly different between MDD patients on Escitalopram and the controls. CONCLUSIONS The hedonic capacity remains different between the two groups despite patients with MDD are put on Escitalopram treatment. Escitalopram fails to alleviate the hedonic state of MDD patients. Antidepressants that improve both depressive symptoms and hedonic states should be considered when treating MDD patients in clinical settings.
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Affiliation(s)
- C G Ng
- Department of Psychological Medicine University Malaya, Kuala Lumpur, Malaysia
| | - S K Wong
- Department of Paediatric University Malaya, Kuala Lumpur, Malaysia
| | - H S Loh
- Clinical Academic Unit, Newcastle University Medicine Malaysia
| | - A Yee
- Department of Psychological Medicine University Malaya, Kuala Lumpur, Malaysia
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Affiliation(s)
- M F Ho
- Division of Upper Gastrointestinal Surgery, Department of Surgery, Prince of Wales Hospital, Chinese University of Hong Kong, Hong Kong SAR, China
| | - A Y Teoh
- Division of Upper Gastrointestinal Surgery, Department of Surgery, Prince of Wales Hospital, Chinese University of Hong Kong, Hong Kong SAR, China
| | - S Y Liu
- Division of Upper Gastrointestinal Surgery, Department of Surgery, Prince of Wales Hospital, Chinese University of Hong Kong, Hong Kong SAR, China
| | - P W Chiu
- Division of Upper Gastrointestinal Surgery, Department of Surgery, Prince of Wales Hospital, Chinese University of Hong Kong, Hong Kong SAR, China
| | - S K Wong
- Division of Upper Gastrointestinal Surgery, Department of Surgery, Prince of Wales Hospital, Chinese University of Hong Kong, Hong Kong SAR, China
| | - E K W Ng
- Division of Upper Gastrointestinal Surgery, Department of Surgery, Prince of Wales Hospital, Chinese University of Hong Kong, Hong Kong SAR, China
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Abstract
The Condition Index (CI) is a method to measure overall health of fish and that has been applied to estimate the effect that different environmental factors have on clam meat quality. The CI of local mangrove clam Polymesoda expansa in Kelulit, Miri Sarawak was determined from October 2010 to November 2011. Condition index that is generally used to characterize the physiological activity of organisms, varied from 1.8% in December 2010 to 3.4% in October 2011, with low values observed during the spawning period. The clam attained their best condition in quality of flesh weight during July-October. In present study, the CI showed a clear relationship with the reproductive cycle of P. expansa. However, no significant correlation (p > 0.05) was found between CI and the different physicochemical parameter of seawater. The data presented is necessary for developing sustainable management strategies and broodstock selection for the species which is crucial in aquaculture development.
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Affiliation(s)
- Azimah Abdul Rahim
- Department of Animal Science and Fishery, Faculty of Agriculture and Food Sciences, Universiti Putra Malaysia, Bintulu Sarawak Campus, Nyabau Road, P.O. Box 396, 97008 Bintulu, Sarawak, Malaysia
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Tan TJ, Wong SK, Foo LSS. A parasymphyseal pubic cartilaginous cyst masquerading as a chondrosarcoma. Clin Radiol 2012; 67:508-10. [PMID: 22305258 DOI: 10.1016/j.crad.2011.12.001] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2011] [Accepted: 12/12/2011] [Indexed: 11/18/2022]
Affiliation(s)
- T J Tan
- Department of Diagnostic Radiology, Singapore General Hospital, Singapore.
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Wong KM, Wong SK. Clinics in diagnostic imaging (136). Chronic Schistosoma japonica infection of the liver. Singapore Med J 2011; 52:694-697. [PMID: 21947150] [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] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
A 37-year-old man from China was initially seen at the urology clinic for symptoms of urinary colic. Plain computed tomography (CT) imaging of the kidneys, ureters and bladder was performed, which (in addition to demonstrating renal calculi) revealed incidental findings of 'turtleback' septal and capsular calcifications, features pathognomonic for schistosomiasis japonica. Other classical features were demonstrated on the triphasic hepatic CT imaging that was subsequently performed. The clinical course, radiological features and complications of schistosomiasis japonica are discussed.
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Affiliation(s)
- K M Wong
- Department of Diagnostic Radiology, Singapore General Hospital, Outram Road, Singapore 169698.
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Affiliation(s)
- A K Fong
- Division of Upper Gastrointestinal Surgery, Department of Surgery, Prince of Wales Hospital, Chinese University of Hong Kong, Hong Kong SAR, China
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19
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Wong SK, Tan WS, Omar AR, Tan CS, Yusoff K. Immunogenic properties of recombinant ectodomain of Newcastle disease virus hemagglutinin-neuraminidase protein expressed in Escherichia coli. Acta Virol 2009; 53:35-41. [PMID: 19301949 DOI: 10.4149/av_2009_01_35] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Hemagglutinin-neuraminidase (HN) protein of Newcastle disease virus (NDV) plays a vital role in the viral infectivity, host immunity, and disease diagnosis. A portion of the HN gene encoding the ectodomain (nt 142-1739) was cloned and expressed in Escherichia coli yielding an insoluble HN protein and a soluble NusA-HN protein containing N-utilization substance A (NusA) fusion component. Both recombinant proteins were purified and used for immunization of chickens. The recombinant HN protein induced higher antibody titers as compared to the recombinant NusA-HN protein. These antibodies were able to react in immunoblot analysis with the corresponding recombinant proteins as well as with the HN protein of NDV.
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Affiliation(s)
- S K Wong
- Department of Microbiology, Universiti Putra Malaysia, Selangor, Malaysia
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20
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Wong SK, Chiu PW, Wu JC, Sung JJ, Ng EK. Trans-cutaneous electrogastrographic study of gastric myoelectric activity in transposed intrathoracic stomach after esophagectomy. Dis Esophagus 2007; 20:69-74. [PMID: 17227314 DOI: 10.1111/j.1442-2050.2007.00641.x] [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] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
We examined the feasibility of trans-cutaneous electrogastrography (EGG) in recording myoelectric activity of the transposed thoracic stomach after esophagectomy. Nineteen patients who had Ivor-Lewis esophagectomy were studied. The EGG signal was recorded using cutaneous electrodes placed over the lower sternum. Eleven patients who underwent total gastrectomy served as controls. Normal rhythm pattern (2.4-3.6 cpm > or = 70%) and power ratio (PR > or = 2) was observed in five and 12 patients, respectively, after esophagectomy. The observation of normal gastric rhythm was more frequent in the postprandial period in the esophagectomy group (median 42.6%vs. 7.4%, P = 0.01), and the PR was significantly higher (median 2.27 vs. 1.38, P = 0.013) than the gastrectomy group. Feeding further increased the prevalence of normal gastric slow wave in the esophagectomy group (median 14.8% to 42.6%, P = 0.002) and improved the stability of dominant frequency (median 78% to 67%, P = 0.015). We conclude that gastric myoelectric activities of thoracic transposed stomach can be detected from cutaneous sternal electrodes. This represented a preservation of gastric motility even when the stomach is pulled up to the thorax as a substitute for the esophagus.
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Affiliation(s)
- S K Wong
- Department of Surgery, Institute of Digestive Diseases, The Chinese University of Hong Kong, Prince of Wales Hospital, Hong Kong, China
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Toh LM, Wong SK. A Case of Cystic Schwannoma of the Lesser Sac. Ann Acad Med Singap 2006. [DOI: 10.47102/annals-acadmedsg.v35n1p45] [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] [Subscribe] [Scholar Register] [Indexed: 03/06/2023]
Abstract
Introduction: Benign cystic schwannoma of the lesser sac is an extremely rare condition and only 3 reports were found in our review of the English literature.
Clinical Picture: We describe a 58-year-old man with a large (5.2 x 6.7 x 7.6 cm) epigastric mass with solid and cystic components detected on sonography and computed tomography. Close association with the pancreas, stomach and liver led to a mistaken diagnosis of pancreatic cystadenoma/cystadenocarcinoma.
Treatment and Outcome: The mass was surgically resected and our patient has been well since.
Conclusion: This case draws the reader’s attention to a rare condition that may mimic other sinister lesions, and highlights the pitfalls of diagnosis. Depending on the size and extent of the lesion, imaging may assist in characterisation of a schwannoma of the lesser sac. Surgical resection would still be the end point of management, especially when mass effect causes debilitating symptoms. Surgery is usually associated with good outcome, and tumour recurrence is unusual, provided adequate margins are resected.
Key words: Benign, Epigastric, Neurilemmoma, Retroperitoneum
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Affiliation(s)
- LM Toh
- Singapore General Hospital, Singapore
| | - SK Wong
- Singapore General Hospital, Singapore
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Toh LM, Wong SK. A case of cystic schwannoma of the lesser sac. Ann Acad Med Singap 2006; 35:45-8. [PMID: 16470274] [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: 05/06/2023]
Abstract
INTRODUCTION Benign cystic schwannoma of the lesser sac is an extremely rare condition and only 3 reports were found in our review of the English literature. CLINICAL PICTURE We describe a 58-year-old man with a large (5.2 x 6.7 x 7.6 cm) epigastric mass with solid and cystic components detected on sonography and computed tomography. Close association with the pancreas, stomach and liver led to a mistaken diagnosis of pancreatic cystadenoma/cystadenocarcinoma. TREATMENT AND OUTCOME The mass was surgically resected and our patient has been well since. CONCLUSION This case draws the reader's attention to a rare condition that may mimic other sinister lesions, and highlights the pitfalls of diagnosis. Depending on the size and extent of the lesion, imaging may assist in characterisation of a schwannoma of the lesser sac. Surgical resection would still be the end point of management, especially when mass effect causes debilitating symptoms. Surgery is usually associated with good outcome, and tumour recurrence is unusual, provided adequate margins are resected.
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Affiliation(s)
- L M Toh
- Department of Diagnostic Imaging, Singapore General Hospital, Singapore.
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23
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Wong SK, Chan VS. Large-aspect-ratio limit of neoclassical transport theory. Phys Rev E Stat Nonlin Soft Matter Phys 2005; 67:066406. [PMID: 16241358 DOI: 10.1103/physreve.67.066406] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/15/2003] [Indexed: 11/07/2022]
Abstract
This paper presents a comprehensive description of neoclassical transport theory in the banana regime for large-aspect-ratio flux surfaces of arbitrary shapes. The method of matched-asymptotic expansions is used to obtain analytical solutions for plasma distribution functions and to compute transport coefficients. The method provides justification for retaining only the part of the Fokker-Planck operator that involves the second derivative with respect to the cosine of the pitch angle for the trapped and barely circulating particles. It leads to a simple equation for the freely circulating particles with boundary conditions that embody a discontinuity separating particles moving in opposite directions. Corrections to the transport coefficients are obtained by generalizing an existing boundary layer analysis. The system of moment and field equations is consistently taken in the cylinder limit, which facilitates the discussion of the treatment of dynamical constraints. It is shown that the nonlocal nature of Ohm's law in neoclassical theory renders the mathematical problem of plasma transport with changing flux surfaces nonstandard.
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Affiliation(s)
- S K Wong
- San Diego Mesa College, San Diego, California 92111, USA
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24
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Dubey JP, Zarnke R, Thomas NJ, Wong SK, Van Bonn W, Briggs M, Davis JW, Ewing R, Mense M, Kwok OCH, Romand S, Thulliez P. Toxoplasma gondii, Neospora caninum, Sarcocystis neurona, and Sarcocystis canis-like infections in marine mammals. Vet Parasitol 2003; 116:275-96. [PMID: 14580799 DOI: 10.1016/s0304-4017(03)00263-2] [Citation(s) in RCA: 172] [Impact Index Per Article: 8.2] [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: 11/19/2022]
Abstract
Toxoplasma gondii, Neospora caninum, Sarcocystis neurona, and S. canis are related protozoans that can cause mortality in many species of domestic and wild animals. Recently, T. gondii and S. neurona were recognized to cause encephalitis in marine mammals. As yet, there is no report of natural exposure of N. caninum in marine mammals. In the present study, antibodies to T. gondii and N. caninum were assayed in sera of several species of marine mammals. For T. gondii, sera were diluted 1:25, 1:50, and 1:500 and assayed in the T. gondii modified agglutination test (MAT). Antibodies (MAT > or =1:25) to T. gondii were found in 89 of 115 (77%) dead, and 18 of 30 (60%) apparently healthy sea otters (Enhydra lutris), 51 of 311 (16%) Pacific harbor seals (Phoca vitulina), 19 of 45 (42%) sea lions (Eumetopias jubatus) [corrected] 5 of 32 (16%) ringed seals (Phoca hispida), 4 of 8 (50%) bearded seals (Erignathus barbatus), 1 of 9 (11.1%) spotted seals (Phoca largha), 138 of 141 (98%) Atlantic bottlenose dolphins (Tursiops truncatus), and 3 of 53 (6%) walruses (Odobenus rosmarus). For N. caninum, sera were diluted 1:40, 1:80, 1:160, and 1:320 and examined with the Neospora agglutination test (NAT) using mouse-derived tachyzoites. NAT antibodies were found in 3 of 53 (6%) walruses, 28 of 145 (19%) sea otters, 11 of 311 (3.5%) harbor seals, 1 of 27 (3.7%) sea lions, 4 of 32 (12.5%) ringed seals, 1 of 8 (12.5%) bearded seals, and 43 of 47 (91%) bottlenose dolphins. To our knowledge, this is the first report of N. caninum antibodies in any marine mammal, and the first report of T. gondii antibodies in walruses and in ringed, bearded, spotted, and ribbon seals. Current information on T. gondii-like and Sarcocystis-like infections in marine mammals is reviewed. New cases of clinical S. canis and T. gondii infections are also reported in sea lions, and T. gondii infection in an Antillean manatee (Trichechus manatus manatus).
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Affiliation(s)
- J P Dubey
- United States Department of Agriculture, Agricultural Research Service, Animal and Natural Resources Institute, Animal Parasitic Diseases Laboratory, Beltsville, MD 20705-2350, USA.
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25
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Abstract
PURPOSE The diagnosis of appendicitis is traditionally made on the basis of clinical findings supported by laboratory results. The aim of our study was to determine the accuracy and feasibility of using a relatively new technique of computed tomography (CT) using only colonic contrast medium. MATERIALS AND METHODS A total of 50 patients clinically diagnosed as having appendicitis were prospectively examined before surgery with thin-collimation helical CT from the L3 level to the acetabular roof with only rectally administered colon contrast medium. The hard copy CT images were reviewed jointly by two radiologists and a consensus was reached for each patient. The results were then compared with the surgical and histological findings at appendicectomy. RESULTS There were 35 true-positives, one false-positive, 12 true-negatives and two false-negatives for CT. This yielded an accuracy of 94%, sensitivity of 95%, specificity of 92%, positive predictive value of 97% and negative predictive value of 86%. The appendix was identified in 45 patients (90%) and obscured by an inflammatory mass in the remaining five. An alternative diagnosis was found in 10 of 12 normal CT examinations (83%). CONCLUSION Helical CT with rectal contrast medium is a quick, well tolerated and accurate test to diagnose appendicitis. It can offer alternative, possibly non-surgical diagnosis in patients who would otherwise have undergone laparotomy.
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Affiliation(s)
- S K Wong
- Departments of Diagnostic Radiology and Surgery, Singapore General Hospital, Singapore
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26
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Lee KBL, Wong SK. Emergency laparoscopic surgery--the Changi General Hospital experience. Ann Acad Med Singap 2002; 31:155-7. [PMID: 11957550] [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: 02/24/2023]
Abstract
INTRODUCTION This paper analyses the emergency laparoscopic procedures undertaken by our unit over a 1-year period in an effort to evaluate the diagnostic-therapeutic use of laparoscopy in an emergency situation. MATERIALS AND METHODS This is a retrospective study that analysed 137 emergency laparoscopic procedures that were performed for patients who presented with acute abdominal pain over a 1-year period from 31 December 1999 to 31 December 2000. RESULTS A definitive diagnosis was made in 91.2% (125). Of the 78 cases that required surgical intervention, 71.8% (56) were performed laparoscopically. The conversion rate (to open surgery) was 16.8% (23) and the morbidity rate was 8% (11); with no mortalities. CONCLUSION We conclude that laparoscopic surgery is effective and safe in the non-elective setting and it offers a high potential for diagnosis and therapy in selected patients in whom the diagnoses are equivocal.
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Affiliation(s)
- K B L Lee
- Department of General Surgery, Changi General Hospital.
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Abstract
BACKGROUND Helicobacter pylori infection has been suggested to be protective against gastro-oesophageal reflux disease. However, a significant proportion of patients with gastro-oesophageal reflux disease are infected by H. pylori. AIM To study oesophageal motor function in H. pylori-infected patients with reflux oesophagitis. METHODS Patients with erosive reflux oesophagitis were recruited prospectively for stationary oesophageal manometry and 24-h ambulatory oesophageal pH monitoring. H. pylori status was determined by biopsy urease test. Non-reflux volunteers were recruited as controls. RESULTS Seventy-four patients with erosive oesophagitis (34 H. pylori-positive, 40 H. pylori-negative) and 48 non-reflux patient controls (22 H. pylori-positive, 26 H. pylori-negative) were recruited. There was no difference in severity of oesophagitis (median grade, 1; P=0.53) or oesophageal acid exposure (total percentage time oesophageal pH < 4, 7.6% vs. 6.8%; P=0.57) between H. pylori-positive and H. pylori-negative groups. Compared to H. pylori-negative patients, H. pylori-positive patients had significantly lower basal lower oesophageal sphincter pressure (12.2 mmHg vs. 15.3 mmHg; P=0.03) and amplitude of distal peristalsis (56.9 mmHg vs. 68.4 mmHg; P=0.03). Ineffective oesophageal motility (14% vs. 7%; P=0.02) and failed oesophageal peristalsis were also significantly more prevalent in H. pylori-positive patients. CONCLUSIONS Among patients with a similar degree of reflux oesophagitis, H. pylori-infected patients have more severe oesophageal dysmotility and lower oesophageal sphincter dysfunction. Oesophageal motor dysfunction probably plays a dominant role in the development of gastro-oesophageal reflux disease in patients with H. pylori infection.
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Affiliation(s)
- J C Wu
- Department of Medicine and Therapeutics, Prince of Wales Hospital, The Chinese University of Hong Kong, Hong Kong.
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Lee DW, Chan AC, Lam YH, Wong SK, Ng EK, Law BK, Chung SC. Subfascial endoscopic perforator vein surgery (SEPS) using the ultrasonic scalpel. Surg Endosc 2001; 15:1491-3. [PMID: 11965479 DOI: 10.1007/s004640000370] [Citation(s) in RCA: 7] [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: 05/15/1999] [Accepted: 09/01/2000] [Indexed: 11/29/2022]
Abstract
Subfascial endoscopic perforator vein surgery (SEPS) was recently introduced as a minimally invasive method to ligate incompetent perforating veins in patients with severe chronic venous insufficiency of the lower extremities. Herein we describe a technique in which we used a 5-mm ultrasonic scalpel for the transection of perforating veins in 16 SEPS performed in 14 patients. The use of the ultrasonic scalpel allowed for the precise coagulation and transection of the perforator vein with hemostasis, while avoiding the use of metal clips. Our initial results showed that the technique was feasible with minimal morbidity. We recommend the use of the ultrasonic scalpel as an alternative tool to transect perforating veins in SEPS.
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Affiliation(s)
- D W Lee
- Department of Surgery, Prince of Wales Hospital, The Chinese University of HongKong, Shatin, N. T., Hong Kong
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Abstract
The present study aimed to evaluate the effectiveness of an interactive multimedia training programme and a conventional therapist-instructed training in improving the learning behaviours of children with autism. A multiple-subject, single case-study time-series research design was adopted in the study. Six children with autism, aged 2 years 4 months to 2 years 10 months, were recruited by convenience sampling. They attended a 12-session training programme on basic concepts (e.g. colours, shapes) that was presented as an interactive multimedia training programme and also as a conventional, therapist-led training programme. The attending behaviours and appropriate responses of the subjects were videotaped for further analysis. Participants who attended the conventional therapist-instructed training programme generally showed improvement in attending behaviours and response rates; participants attending the multimedia programme also showed improvement in their attending behaviours and response rates. The results support the hypothesis that both training programmes are effective in improving the attending behaviours and appropriate responses of children with autism. The authors suggest that, because children with autism respond differently to different training approaches, customized training programmes should be considered for individual children. The implications of the methodology and the potential impact of the present study on the training of children with autism are discussed.
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Affiliation(s)
- S K Wong
- Department of Rehabilitation Sciences, The Hong Kong Polytechnic University, Hung Hom, Kowloon
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30
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Wong SK, Ng LG, Tan BS, Cheng CW, Chee CT, Chan LP, Lo HG. Acute renal colic: value of unenhanced spiral computed tomography compared with intravenous urography. Ann Acad Med Singap 2001; 30:568-72. [PMID: 11817281] [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: 02/23/2023]
Abstract
OBJECTIVE The objective of this study was to compare the efficacy of plain spiral computed tomographic (CT) scan with intravenous urography (IVU) in the evaluation of patients with suspected urinary calculi/obstruction. MATERIALS AND METHODS Twenty consecutive patients with acute signs of renal colic were prospectively examined with unenhanced spiral CT followed by an IVU within the same day. The CT scans were reviewed jointly by 2 radiologists blinded to the IVU and a consensus was reached for each finding. The IVU was similarly reviewed by another 2 separate radiologists. RESULTS Eleven of the 20 patients had signs of urinary obstruction on CT and IVU. Of these 11 patients, 7 had a ureteric calculus that was demonstrated on CT and IVU and 4 had a calculus that was demonstrated on CT only. Two patients had a urinary calculus seen on CT and IVU with no signs of urinary obstruction. One patient had a calculus seen on CT alone with no urinary obstruction. Two patients only had signs of urinary obstruction on CT. The remaining 4 cases had normal findings on CT and IVU. CONCLUSION Unenhanced CT is more effective than IVU in identifying ureteric calculi and is equally effective in detecting urinary obstruction. CT is also useful in detecting secondary signs of obstruction even in the absence of any calculus.
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Affiliation(s)
- S K Wong
- Department of Diagnostic Radiology, Singapore General Hospital, Outram Road, Singapore 169608
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31
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Abstract
PURPOSE An aggressive surgical approach with en bloc resection of involved structures is often possible with anterior rectal cancers that invade adjacent visceral organs, but is rarely possible in tumors that invade the pelvic wall. However, most staging systems include both situations in the same group of T4 rectal cancers. We performed a retrospective study of patients with stage T4 rectal cancer undergoing surgery to assess the influence of different organ involvement on resectability and survival. METHODS A retrospective review was conducted of 84 patients with T4 rectal cancer treated at the University of Minnesota and affiliated hospitals over a ten-year period. Forty-seven patients (56 percent) were staged for local invasion on the basis of final pathology, 19 (23 percent) on the basis of operative findings, and 18 (21 percent) on the basis of ultrasound images. Patients were divided into two groups, those with or without pelvic wall involvement. Resectability, local control, and overall survival were compared between groups. Survival curves were estimated by the Kaplan-Meier method and compared by log-rank test. Multivariate analysis was performed with Cox proportional and logistic regression. RESULTS Thirty-one patients (37 percent) had involvement of the pelvic wall, whereas 53 patients (63 percent) had visceral involvement only. All 29 patients with distant metastasis died of their disease. Forty-seven of the 55 patients without distant metastasis underwent tumor resection. Age and pelvic wall involvement were the only two factors independently associated with the probability of resection in logistic regression analysis (P = 0.0067 and P = 0.037, respectively). The only factor that affected median survival in patients without distant metastasis was tumor resection (49.1 months for resection vs. 6.1 months for no resection, P = 0.017). Patients with visceral involvement had a longer median survival (49.2 months) than those with pelvic wall involvement (13.2 months), but the difference did not reach statistical significance (P = 0.058). CONCLUSION Rectal cancers with pelvic and visceral involvement have different rates of resectability and median survival. These differences should be reflected in the TNM classification system.
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Affiliation(s)
- R Yiu
- Division of Colon and Rectal Surgery, University of Minnesota Cancer Center, Minneapolis, Minnesota, USA
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Abstract
INTRODUCTION There are no previous comparative studies of total abdominal colectomy by laparoscopic methods in ulcerative colitis and Crohn's disease patients requiring urgent colectomy. This study aimed to determine the safety and efficacy of laparoscopic colectomy in these patients compared with those undergoing conventional urgent colectomy. METHODS Patients undergoing laparoscopic total colectomy for acute colitis were identified in a prospective registry. All patients underwent a total colectomy with creation of an end ileostomy and buried mucous fistula. No patient had fulminant disease (tachycardia, fever, marked leukocytosis, peritonitis), but all were failing to respond to medical treatment. Patients undergoing conventional total colectomy were matched for age, gender, body mass index, diagnosis, disease severity, and operative period. Median values (range) are listed. RESULTS From 1997 to 1999, there were 19 laparoscopic and 29 matched conventional patients. There were no inadvertent colotomies or conversions in the laparoscopic group. Although there was no difference in operative blood loss in the laparoscopic group (100 (range, 50-700) ml) when compared with the conventional group (150 (range, 50-500) ml), the operative times were significantly longer in the laparoscopic group (210 (range, 150-270) vs. 120 (range, 60-180) minutes, P < 0.001). Bowel function returned more quickly in the laparoscopic group (1 (range, 1-3) vs. 2 (range, 1-4) days; P = 0.003) and the length of stay was shorter (4 (range, 3-13) vs. 6 (range, 4-24) days; P = 0.04). Complications occurred in three (16 percent) laparoscopic patients (2 wound infection and 1 ileus) and in seven (24 percent) conventional patients (3 wound infection, 3 deep venous thrombosis, 1 upper gastrointestinal bleed). CONCLUSIONS Laparoscopic total colectomy is feasible and safe in patients with acute nonfulminant colitis and may lead to a faster recovery than conventional resection.
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Affiliation(s)
- P W Marcello
- Department of Colon & Rectal Surgery, Labey Clinic, Burlington, Massachusetts, USA
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Abstract
A host-mediated RNA-editing event allows hepatitis delta virus (HDV) to express two essential proteins, the small delta antigen (HDAg-S) and the large delta antigen (HDAg-L), from a single open reading frame. One or several members of the ADAR (adenosine deaminases that act on RNA) family are thought to convert the adenosine to an inosine (I) within the HDAg-S amber codon in antigenomic RNA. As a consequence of replication, the UIG codon is converted to a UGG (tryptophan [W]) codon in the resulting HDAg-L message. Here, we used a novel reporter system to monitor the editing of the HDV amber/W site in the absence of replication. In cultured cells, we observed that both human ADAR1 (hADAR1) and hADAR2 were capable of editing the amber/W site with comparable efficiencies. We also defined the minimal HDV substrate required for hADAR1- and hADAR2-mediated editing. Only 24 nucleotides from the amber/W site were sufficient to enable efficient editing by hADAR1. Hence, the HDV amber/W site represents the smallest ADAR substrate yet identified. In contrast, the minimal substrate competent for hADAR2-mediated editing contained 66 nucleotides.
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Affiliation(s)
- S Sato
- Department of Molecular Biology and Microbiology, Sackler School of Graduate Biomedical Sciences, Tufts University School of Medicine, Boston, Massachusetts 02111, USA
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35
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Wang WX, Hinton FL, Wong SK. Neoclassical radial electric field and transport with finite orbits. Phys Rev Lett 2001; 87:055002. [PMID: 11497780 DOI: 10.1103/physrevlett.87.055002] [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] [Subscribe] [Scholar Register] [Received: 03/01/2001] [Indexed: 05/23/2023]
Abstract
Neoclassical transport in a toroidal plasma with finite ion orbits is studied, including for the first time the self-consistent radial electric field. Using a low-noise deltaf particle simulation, we demonstrate that a deep electric-field well develops in a region with a steep density gradient, because of the self-collision-driven ion flux. We find that the electric field agrees with the standard neoclassical expression, when the toroidal rotation is zero, even for a steep density gradient. Ion thermal transport is modified by the electric-field well in a way which is consistent with the orbit squeezing effect, but smoothed by the finite orbits.
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Affiliation(s)
- W X Wang
- General Atomics, P.O. Box 85608, San Diego, California 92186, USA
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Lee DW, Chan AC, Lam YH, Wong SK, Fung TM, Mui LM, Ng EK, Chung SC. Early clinical outcomes after subfascial endoscopic perforator surgery (SEPS) and saphenous vein surgery in chronic venous insufficiency. Surg Endosc 2001; 15:737-40. [PMID: 11591980 DOI: 10.1007/s004640090050] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.4] [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: 08/28/2000] [Accepted: 09/11/2000] [Indexed: 11/30/2022]
Abstract
BACKGROUND Subfascial endoscopic perforator surgery (SEPS) has recently become popular as a minimally invasive way to treat chronic venous insufficiency (CVI) of the lower extremities. We report the early clinical outcomes of SEPS and saphenous vein surgery in a prospective series of Chinese patients who presented with severe CVI. METHODS All patients referred to our hospital for the management of severe CVI (class IV disease or above) after January 1998 underwent SEPS using an ultrasonic scalpel in conjunction with saphenous vein surgery. All patients were followed up prospectively to assess ulcer healing, ulcer recurrence, and symptoms after SEPS. Clinical outcome was evaluated by the scoring system suggested by the Consensus Committee of the American Venous Forum on Chronic Venous Disease. RESULTS Over a 24-month period, we performed 36 SEPS on 31 patients. Nineteen lower extremities (53%) had active or healing ulcers. Sapheno-femoral ligation was also performed in 33 limbs (92%). Four limbs (11%) developed superficial wound infection, and two (6%) had saphenous nerve dysesthesia. The mean clinical score and disability score decreased from 8.42 to 3.42 and 1.45 to 0.31 respectively, after a median follow-up of 14 months (range, 6-22) (p < 0.005). Eleven ulcers (58%) healed within 6 weeks after surgery. At 1-year follow-up, ulcer recurrence was found in two legs (11%). CONCLUSION SEPS is safe and feasible. Early clinical results have shown a promising outcome in patients with severe chronic venous insufficiency.
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Affiliation(s)
- D W Lee
- Department of Surgery, Prince of Wales Hospital, The Chinese University of Hong Kong, Shatin, N.T., Hong Kong, China
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37
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Abstract
RNA editing catalyzed by ADAR1 and ADAR2 involves the site-specific conversion of adenosine to inosine within imperfectly duplexed RNA. ADAR1- and ADAR2-mediated editing occurs within transcripts of glutamate receptors (GluR) in the brain and in hepatitis delta virus (HDV) RNA in the liver. Although the Q/R site within the GluR-B premessage is edited more efficiently by ADAR2 than it is by ADAR1, the converse is true for the +60 site within this same transcript. ADAR1 and ADAR2 are homologs having two common functional regions, an N-terminal double-stranded RNA-binding domain and a C-terminal deaminase domain. It is neither understood why only certain adenosines within a substrate molecule serve as targets for ADARs, nor is it known which domain of an ADAR confers its specificity for particular editing sites. To assess the importance of several aspects of RNA sequence and structure on editing, we evaluated 20 different mutated substrates, derived from four editing sites, for their ability to be edited by either ADAR1 or ADAR2. We found that when these derivatives contained an A:C mismatch at the editing site, editing by both ADARs was enhanced compared to when A:A or A:G mismatches or A:U base pairs occurred at the same site. Hence substrate recognition and/or catalysis by ADARs could involve the base that opposes the edited adenosine. In addition, by using protein chimeras in which the deaminase domains were exchanged between ADAR1 and ADAR2, we found that this domain played a dominant role in defining the substrate specificity of the resulting enzyme.
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Affiliation(s)
- S K Wong
- Department of Molecular Biology and Microbiology, Tufts University School of Medicine, Boston, Massachusetts 02111, USA
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Hinton FL, Rosenbluth MN, Wong SK, Lin-Liu YR, Miller RL. Modified lattice Boltzmann method for compressible fluid simulations. Phys Rev E Stat Nonlin Soft Matter Phys 2001; 63:061212. [PMID: 11415085 DOI: 10.1103/physreve.63.061212] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/22/2000] [Indexed: 05/23/2023]
Abstract
A modified lattice Boltzmann algorithm is shown to have much better stability to growing temperature perturbations, when compared with the standard lattice Boltzmann algorithm. The damping rates of long-wavelength waves, which determine stability, are derived using a collisional equilibrium distribution function which has the property that the Euler equations are obtained exactly in the limit of zero time step. Using this equilibrium distribution function, we show that our algorithm has inherent positive hyperviscosity and hyperdiffusivity, for very small values of viscosity and thermal diffusivity, which are lacking in the standard algorithm. Short-wavelength modes are shown to be stable for temperatures greater than a lower limit. Results from a computer code are used to compare these algorithms, and to confirm the damping rate predictions made analytically. Finite amplitude sound waves in the simulated fluid steepen, as expected from gas dynamic theory.
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Affiliation(s)
- F L Hinton
- General Atomics, San Diego, California 92186-9784, USA
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Abstract
Integration of retrovirus DNA is a specific process catalyzed by the integrase protein acting to join the viral substrate DNA (att) sequences of about 10 bases at the ends of the long terminal repeat (LTR) to various sites in the host target cell DNA. Although the interaction is sequence specific, the att sequences of different retroviruses are largely unrelated to one another and usually differ between the two ends of the viral DNA. To define substrate sequence specificity, we designed an "in vitro evolution" scheme to select an optimal substrate sequence by competitive integration in vitro from a large pool of partially randomized substrates. Integrated substrates are enriched by PCR amplification and then regenerated and subjected to subsequent cycles of selection and enrichment. Using this approach, we obtained the optimal substrate sequence of 5'-ACGACAACA-3' for avian sarcoma-leukosis virus (ASLV) and 5'-AACA(A/C)AGCA-3' for human immunodeficiency virus type 1, which differed from those found at both ends of the viral DNA. Clonal analysis of the integration products showed that ASLV integrase can use a wide variety of substrate sequences in vitro, although the consensus sequence was identical to the selected sequence. By a competition assay, the selected nucleotide at position 4 improved the in vitro integration efficiency over that of the wild-type sequence. Viral mutants bearing the optimal sequence replicated at wild-type levels, with the exception of some mutations disrupting the U5 RNA secondary structure important for reverse transcription, which were significantly impaired. Thus, maximizing the efficiency of integration may not be of major importance for efficient retrovirus replication.
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Affiliation(s)
- H Zhou
- Departments of Molecular Biology and Microbiology, Tufts University School of Medicine, Boston, Massachusetts 02111, USA
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40
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Abstract
An API-LC/MS/MS method was developed for the identification of the medicinal herb Podophyllum emodi based on the profile of its aryltetrahydronapthalene and related lignan marker compounds. This was done by matching the structural information from the tandem mass spectrometric data with those lignan marker compounds already reported for the herb. The method could be employed in the absence of reference standards for the markers and was particularly useful in view of the scarcity of supply of these chemical standards. It has been used successfully to differentiate Podophyllum emodi from two commonly used medicinal herbs of a different genus but having similar appearance, Radix clematidis and Radix gentiana, as well as a closely related herb, Podophyllum peltatum.
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Affiliation(s)
- S K Wong
- Government Laboratory, 88 Chung Hau Street, Homantin, Hong Kong SAR, People's Republic of China
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Lau JY, Sung JJ, Lee KK, Yung MY, Wong SK, Wu JC, Chan FK, Ng EK, You JH, Lee CW, Chan AC, Chung SC. Effect of intravenous omeprazole on recurrent bleeding after endoscopic treatment of bleeding peptic ulcers. N Engl J Med 2000; 343:310-6. [PMID: 10922420 DOI: 10.1056/nejm200008033430501] [Citation(s) in RCA: 414] [Impact Index Per Article: 17.3] [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: 12/30/2022]
Abstract
BACKGROUND After endoscopic treatment of bleeding peptic ulcers, bleeding recurs in 15 to 20 percent of patients. METHODS We assessed whether the use of a high dose of a proton-pump inhibitor would reduce the frequency of recurrent bleeding after endoscopic treatment of bleeding peptic ulcers. Patients with actively bleeding ulcers or ulcers with nonbleeding visible vessels were treated with an epinephrine injection followed by thermocoagulation. After hemostasis had been achieved, they were randomly assigned in a double-blind fashion to receive omeprazole (given as a bolus intravenous injection of 80 mg followed by an infusion of 8 mg per hour for 72 hours) or placebo. After the infusion, all patients were given 20 mg of omeprazole orally per day for eight weeks. The primary end point was recurrent bleeding within 30 days after endoscopy. RESULTS We enrolled 240 patients, 120 in each group. Bleeding recurred within 30 days in 8 patients (6.7 percent) in the omeprazole group, as compared with 27 (22.5 percent) in the placebo group (hazard ratio, 3.9; 95 percent confidence interval, 1.7 to 9.0). Most episodes of recurrent bleeding occurred during the first three days, which made up the infusion period (5 in the omeprazole group and 24 in the placebo group, P<0.001). Three patients in the omeprazole group and nine in the placebo group underwent surgery (P=0.14). Five patients (4.2 percent) in the omeprazole group and 12 (10 percent) in the placebo group died within 30 days after endoscopy (P=0.13). CONCLUSIONS After endoscopic treatment of bleeding peptic ulcers, a high-dose infusion of omeprazole substantially reduces the risk of recurrent bleeding.
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Affiliation(s)
- J Y Lau
- Department of Surgery, Chinese University of Hong Kong, Shatin
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Abstract
Packaging has become an indispensible element in the food manufacturing process, and different types of additives, such as antioxidants, stabilizers, lubricants, anti-static and anti-blocking agents, have also been developed to improve the performance of polymeric packaging materials. Recently the packaging has been found to represent a source of contamination itself through the migration of substances from the packaging into food. Various analytical methods have been developed to analyze the migrants in the foodstuff, and migration evaluation procedures based on theoretical prediction of migration from plastic food contact material were also introduced recently. In this paper, the regulatory control, analytical methodology, factors affecting the migration and migration evaluation are reviewed.
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Affiliation(s)
- O W Lau
- Department of Chemistry, The Chinese University of Hong Kong, Shatin, N.T.
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Marcello PW, Milsom JW, Wong SK, Hammerhofer KA, Goormastic M, Church JM, Fazio VW. Laparoscopic restorative proctocolectomy: case-matched comparative study with open restorative proctocolectomy. Dis Colon Rectum 2000; 43:604-8. [PMID: 10826418 DOI: 10.1007/bf02235570] [Citation(s) in RCA: 191] [Impact Index Per Article: 8.0] [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: 02/08/2023]
Abstract
PURPOSE A laparoscopic approach to restorative proctocolectomy is new and has not been compared recently with the traditional open procedure. By using prospectively gathered data, laparoscopic and open restorative proctocolectomy procedures in mucosal ulcerative colitis and familial adenomatous polyposis patients were compared by using a case-matched design. METHODS Forty patients, composing 20 consecutive laparoscopic cases (13 mucosal ulcerative colitis, 7 familial adenomatous polyposis), were matched for age, gender, and body mass index with 20 open cases (13 mucosal ulcerative colitis, 7 familial adenomatous polyposis) performed during the same time period. Mucosal ulcerative colitis patients were also matched for severity of disease by using hemoglobin and albumin levels, whole blood count, and steroid dependency. A loop ileostomy was made in 12 of 13 laparoscopic mucosal ulcerative colitis patients, all open mucosal ulcerative colitis patients, and no familial adenomatous polyposis patients. RESULTS The median age was 25 (range, 9-61) years. There were no intraoperative complications in either group and no conversions in the laparoscopic group. The operative times (median, range) were significantly longer in laparoscopic cases (330, 180-480 minutes) vs. open cases (230, 180-300 minutes), P < 0.001. Bowel function returned more quickly in laparoscopic cases (2, 1-8 days) vs. open cases (4, 1-13 days), P = 0.03; and the length of stay was shorter in laparoscopic cases (7, 4-14 days) vs. open cases (8, 6-17 days), P = 0.02. For diverted patients, the median length of stay was reduced by two days in laparoscopic cases (6, 4-14 days) vs. open cases (8, 6-17 days), P = 0.01. Complications occurred in 4 of 20 laparoscopic patients (3 obstruction/ileus and 1 pelvic abscess) and 5 of 20 open patients (2 obstruction and ileus, 1 each anastomotic leak and abscess, peptic ulceration, and episode of dehydration). CONCLUSIONS Return of intestinal function and length of stay are reduced in the laparoscopic group compared with open group. A laparoscopic approach to restorative proctocolectomy has the potential of becoming an appealing alternative to conventional restorative proctocolectomy surgery.
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Affiliation(s)
- P W Marcello
- Department of Colorectal Surgery, Cleveland Clinic Foundation, Ohio, USA
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Wu JC, Sung JJ, Chan FK, Ching JY, Ng AC, Go MY, Wong SK, Ng EK, Chung SC. Helicobacter pylori infection is associated with milder gastro-oesophageal reflux disease. Aliment Pharmacol Ther 2000; 14:427-32. [PMID: 10759622 DOI: 10.1046/j.1365-2036.2000.00714.x] [Citation(s) in RCA: 65] [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] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
BACKGROUND We have previously demonstrated a negative relationship between the prevalence of Helicobacter pylori and gastro-oesophageal reflux disease (GERD). AIM To study the effects of H. pylori infection on the severity of GERD. METHODS Ethnic Chinese patients with frequent heartburn and/or endoscopic oesophagitis were studied. Endoscopic examination was performed to assess the severity of oesophagitis (modified Savary-Miller grading) and the presence of hiatus hernia. Biopsies were taken for rapid urease testing and confirmation of Barrett's oesophagus. Risk factors which may affect the severity of oesophagitis (age, sex, smoking, drinking, diabetes mellitus, hiatus hernia, H. pylori status and body mass index) were evaluated by a multiple regression model. The cagA status of H. pylori infected GERD and age-and-sex matched controls were determined by Western blot. Age-and-sex matched non-reflux patients were recruited as controls for comparison. RESULTS Two hundred and twenty-five patients with GERD were studied, of whom 77 (34%) were infected with H. pylori. Oesophagitis and Barrett's oesophagus were found in 140 patients (62%) and six patients (3%), respectively. H. pylori infected patients had significantly less severe oesophagitis compared to the uninfected group (P=0.022). All patients with Barrett's oesophagus were uninfected. Factors that predicted severe oesophagitis included age over 60 years (P < 0.001) and hiatus hernia (P < 0.001). H. pylori infection was the only factor that showed a negative correlation with severe oesophagitis (P=0.011). The prevalence of the cagA positive strain in endoscopy-negative GERD, erosive oesophagitis and control subjects was 70, 76 and 78%, respectively (P=0.75). CONCLUSIONS H. pylori infection is associated with milder GERD.
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Affiliation(s)
- J C Wu
- Department of Medicine & Therapeutics, The Chinese University of Hong Kong, Shatin, Hong Kong; Department of Surgery, The Chinese University of Hong Kong, Shatin, Hong Kong
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Wong SK, Lam YH, Lau JY, Lee DW, Chan AC, Chung SC. Diagnostic and therapeutic fistuloscopy: an adjuvant management in postoperative fistulas and abscesses after upper gastrointestinal surgery. Endoscopy 2000; 32:311-3. [PMID: 10774971 DOI: 10.1055/s-2000-7378] [Citation(s) in RCA: 26] [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] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
BACKGROUND AND STUDY AIMS Postoperative fistulas and abscesses pose difficult management problems. We report our experience in the use of fistuloscopy in postoperative fistulas and abscesses after upper gastrointestinal surgery. PATIENTS AND METHODS From June 1993 to January 1997, nine patients (seven men, two women; mean age 65) with postoperative fistulas and abscesses were treated with therapeutic fistuloscopy. Diagnostic fistuloscopy was carried out using a 5-mm choledochoscope under fluoroscopic guidance. Therapeutic procedures included mechanical debridement, irrigation, and sealing of fistula with fibrin sealant and gelatin sponge. RESULTS The patients were suffering from duodenal stump fistula (three cases), gastrojejunostomy dehiscence after gastrectomy (three cases), gastropleurocutaneous fistula (two cases), and subphrenic abscesses (two cases). Fistuloscopy was performed 4-19 days (mean 12 days) after the diagnosis of the fistula. The median number of sessions required was 2 (range 1-4). The average daily fistula output prior to fistuloscopy was 154 ml (range 30-560 ml), and all fistulas healed in an average of 18.7 days (range 2-46 days) after index fistuloscopy. No procedure-related complications occurred. The mean hospital stay was 61 days. During a mean follow-up period of 12 months, no recurrent abscesses or fistulas developed. CONCLUSIONS Fistuloscopy provides a new means of managing patients with postoperative fistula and abscess formation.
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Affiliation(s)
- S K Wong
- Dept. of Surgery, The Chinese University of Hong Kong, Prince of Wales Hospital, Shatin, SAR, China
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Affiliation(s)
- S K Wong
- Departments of Surgery, The Chinese University of Hong Kong, Prince of Wales Hospital, Shatin, NT, Hong Kong, China
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Abstract
BACKGROUND Liver abscess is commonly biliary in origin. We assessed the role of endoscopic retrograde cholangiopancreatography (ERCP) in patients with pyogenic liver abscesses. METHODS Between January 1986 and December 1997, 63 patients with pyogenic liver abscesses were referred for ERCP. Twenty-one patients had a history of previous biliary procedures including cholecystectomy (21), biliary-enteric bypass (9), surgical sphincteroplasty (5), and endoscopic sphincterotomy (2). Demographic data, clinical features, biochemical parameters, treatment, clinical progress, and follow-up were recorded and analyzed. RESULTS Two patients required laparotomy and 61 patients underwent guided aspiration and/or drainage at a median interval of 3 days after presentation. ERCP was performed at a median of 8 days (range 1 to 69 days) after initial treatment and succeeded in 90% of cases with no associated complication or death. Abnormalities were shown in 29 (46%) patients: biliary obstruction due to stones or strictures (15), ductal dilatation alone (7), spontaneous choledochoduodenal fistula (3), communication between abscesses and biliary tree (3), and splaying of biliary ducts by space-occupying effect (2). No abnormality was found in 34 patients. Eight patients underwent endoscopic therapy including sphincterotomy (5), stone extraction (6), and nasobiliary drainage (2). Overall mortality rate from liver abscesses was 6%. CONCLUSIONS ERCP is useful in the treatment of patients with pyogenic liver abscesses.
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Affiliation(s)
- Y H Lam
- Department of Surgery, Chinese University of Hong Kong, Prince of Wales Hospital, Shatin, Hong Kong SAR
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Wong SK. Leiomyoma of the epididymis. Singapore Med J 1999; 40:537-8. [PMID: 10572496] [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] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/14/2023]
Abstract
Epididymal leiomyomas are rare intrascrotal neoplasms. It is a slow growing tumour and usually present as an enlarged, painless scrotal mass. A case with an unusual presentation is reported with a review of the possible sonographic findings of this entity and the differential diagnosis of a mass in the epididymis.
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Affiliation(s)
- S K Wong
- Department of Diagnostic Radiology, Singapore General Hospital, Singapore
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Wong SK, Feinstein LH, Heidmann P. Healthy pets, healthy people. J Am Vet Med Assoc 1999; 215:335-8. [PMID: 10434969] [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] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/13/2023]
Abstract
Zoonoses, diseases that can be transmitted from animals to humans, can pose serious health risks to immunocompromised people. Although pets can carry zoonoses, owning and caring for animals can benefit human health. Information exists about preventing transmission of zoonoses, but not all physicians and veterinarians provide adequate and accurate information to immunocompromised pet owners. This disease prevention/health promotion project provides physicians and veterinarians with information, created specifically to share with patients and clients, about the health risks and benefits of pet ownership. Further, "Healthy Pets, Healthy People" encourages communication between veterinarians, physicians, clients, and patients and can serve as a model program for a nation-wide effort to aid health professionals in making recommendations about pet ownership for immunocompromised people.
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Affiliation(s)
- S K Wong
- School of Veterinary Medicine, Tufts University, North Grafton, Mass. 01536, USA
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Wong SK. Acculturation, peer relations, and delinquent behavior of Chinese-Canadian youth. Adolescence 1999; 34:107-19. [PMID: 10234371] [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: 02/12/2023]
Abstract
Studies have reported that youth of Chinese descent in North America tend to have lower rates of delinquency. Some investigators have attributed this phenomenon to the restraining effects of Chinese culture. In this study, acculturation, peer relations, and delinquency were examined in a sample of Chinese-Canadian youth. The results revealed that adherence to Chinese culture was related to lower delinquency, whereas the opposite was true for North American acculturation. It was found that association with delinquent peers was positively related and attachment to peers negatively related to delinquency, as predicted by differential association and control theories, respectively. Moreover, acculturation was positively related to association with delinquent peers and attachment to peers. However, there was the unexpected finding that association with Chinese peers was positively related to delinquency. These seemingly contradictory findings demonstrate the dilemma experienced by Chinese youth in North America.
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Affiliation(s)
- S K Wong
- Department of Sociology, Brandon University, Manitoba, Canada
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