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Rajekar H, Wai CT, Majeed TA, Lee KH, Wong SY, Leong SO, Singh R, Tay KH, Soosaynathan C, Tan KC. Prognostic factors in patients with acute liver failure undergoing live donor liver transplantation. Transplant Proc 2008; 40:2492-3. [PMID: 18929776 DOI: 10.1016/j.transproceed.2008.07.009] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023]
Abstract
Mortality from acute liver failure (ALF) is high. Live donor liver transplantation (LDLT) is the treatment of choice for ALF in Asia, because cadaveric donors are rare. We sought to review our results in ALF patients with undergoing LDLT at our center. One hundred two LDLTs were performed at our center from April 2002 to November 2007, 15 (14%) because of ALF. Mean (SEM; median, range) follow-up was 1,065 (189; 1400; 3-2046) days. Nine patients (60%) had acute exacerbation of chronic hepatitis B; and 6 (40%) had drug-induced liver injury. Age was 47 (3; 50; 27-65) years. Ten patients (67%) were men. At transplantation, laboratory values were included bilirubin, 449 (35) micromol/L; creatinine concentration, 182 (32) mmol/L. The international normalized ratio was 2.4 (0.2). The Model for End-Stage Liver Disease (MELD) score was 34 (2). Both inpatient and long-term mortality was 20% 3 of 15 patients died. The 5-year survival was 80%. Compared with survivors, patients who died had a significantly higher creatinine concentration 289 vs 155 micromol/L, international normalized ratio (3.4 vs 2.1), MELD score (47 vs 32). We conclude that despite being sick with median and mean MELD scores of 32 and 34, 80% of patients with ALF can achieve good long-term survival after LDLT.
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Hsu LY, Kwa AL, Lye DC, Chlebicki MP, Tan TY, Ling ML, Wong SY, Goh LG. Reducing antimicrobial resistance through appropriate antibiotic usage in Singapore. Singapore Med J 2008; 49:749-755. [PMID: 18946605] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/27/2023]
Abstract
Two alarming trends threaten the future utility of antimicrobial agents: rise of antimicrobial resistance and decline in development of new antibiotics. The continuing emergence and spread of antimicrobial-resistant microbes--a global public health issue--exacerbates the problem of paucity of new antimicrobial agents. Singapore's public sector hospitals currently have some of the highest rates of antimicrobial resistance worldwide, evolving with surprising speed over the past two decades. Because there was no systematic surveillance until fairly recently, this healthcare problem has not been emphasised. In contrast, it is difficult to assess the scale of antimicrobial resistance in the community in view of the lack of recent research, although indirect evidence suggests that this is also a source of concern. A panel comprising representatives from multiple professional healthcare societies was convened to address the issue of antimicrobial resistance in Singapore, focusing on the conservation of antibiotics against resistance. From a review of the medical literature, potentially successful strategies involve facilitating prudent and appropriate use of antimicrobial agents in tandem with other interventions in infection control. Presently, there is a lack of data on the appropriate use of antibiotics in Singapore. The recommendations of the panel are: The professions should look into ways and means to support systematic data collection on antibiotic use and appropriateness of use; The Ministry of Health should take a more active and positive role in regulating antibiotic usage; Hospitals should actively support effective antimicrobial stewardship programmes; Educators should coordinate programmes to give greater emphasis on appropriate antimicrobial prescription, and support good clinical practice; and, Local and regional branches of pharmaceutical companies should adopt the Pharmaceutical Research and Manufacturers of America's updated code of conduct on interactions with physicians as a step towards re-aligning the industry-physician relationship in the direction of educational and informational support.
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Tan K, Lim SA, Thomas A, Lim CT, Wong SY, Tan CB. Idiopathic hypertrophic pachymeningitis causing seizures. Eur J Neurol 2007; 15:e12-3. [PMID: 18093150 DOI: 10.1111/j.1468-1331.2007.02023.x] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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Chiu TW, Lam CK, Wong SY, Lau YK, Ying SY, Burd A. A simple practical model for planning tissue-expanded flaps. J Plast Reconstr Aesthet Surg 2007; 60:686-7. [PMID: 17485060 DOI: 10.1016/j.bjps.2006.11.029] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2006] [Accepted: 11/30/2006] [Indexed: 11/16/2022]
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Abstract
Necrotizing fasciitis is an uncommon but life-threatening complication in immunocompromised hosts. We reported four patients with rheumatic diseases complicated by necrotizing fasciitis and reviewed 14 others from literature search. Most patients were on corticosteroid treatment. Septic shock, disseminated intravascular coagulopathy and acute renal deterioration were common giving rise to an overall mortality rate of 27.8%. Septic arthritis may also complicate the condition. Statistical analysis on the series showed the lack of major surgical debridement as the only risk factor associated with increased mortality (RR 7.5, 95% CI 2.1-27.3, P = 0.01). Timely debridement of necrotic tissue is important for reducing mortality.
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MESH Headings
- Adult
- Aeromonas/isolation & purification
- Animals
- Anti-Bacterial Agents/therapeutic use
- Arthritis, Infectious/etiology
- Arthritis, Rheumatoid/complications
- Arthritis, Rheumatoid/drug therapy
- Arthroplasty, Replacement, Hip
- Combined Modality Therapy
- Cyclophosphamide/adverse effects
- Cyclophosphamide/therapeutic use
- Debridement
- Disseminated Intravascular Coagulation/etiology
- Fasciitis, Necrotizing/drug therapy
- Fasciitis, Necrotizing/etiology
- Fasciitis, Necrotizing/surgery
- Fatal Outcome
- Female
- Femur Head Necrosis/chemically induced
- Femur Head Necrosis/surgery
- Fishes/microbiology
- Gram-Negative Bacterial Infections/drug therapy
- Gram-Negative Bacterial Infections/etiology
- Gram-Negative Bacterial Infections/surgery
- Humans
- Immunocompromised Host
- Immunosuppressive Agents/adverse effects
- Immunosuppressive Agents/therapeutic use
- Lupus Erythematosus, Systemic/complications
- Lupus Erythematosus, Systemic/drug therapy
- Middle Aged
- Prednisolone/adverse effects
- Prednisolone/therapeutic use
- Pseudomonas Infections/drug therapy
- Pseudomonas Infections/etiology
- Pseudomonas Infections/surgery
- Scleroderma, Diffuse/complications
- Scleroderma, Diffuse/drug therapy
- Shock, Septic/etiology
- Skin/injuries
- Skin Transplantation
- Streptococcal Infections/drug therapy
- Streptococcal Infections/etiology
- Streptococcal Infections/surgery
- Surgical Wound Infection/etiology
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Wong SY, Lai AC, Martinson I, Wong TKS. Effects of an education programme on family participation in the rehabilitation of children with developmental disability. JOURNAL OF INTELLECTUAL DISABILITIES : JOID 2006; 10:165-89. [PMID: 16682391 DOI: 10.1177/1744629506064012] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/09/2023]
Abstract
The growth and development of children with developmental disability depend very much on the parents. The present study was designed to examine whether family-focused education could enhance parental skills, knowledge and competency. The enhancement would in turn result in greater parental participation in the rehabilitation process of these children. The parental needs of Chinese parents were reviewed for the formulation of the Family-Focused Education Programme, which was then implemented, and evaluated using a pre-test/post-test control group design. Forty parents were invited to participate in the study using a convenience sampling technique. The mean scores of these variables were in the direction of increasing after the programme, though repeated measures ANOVA did not indicate any statistically significant changes in parenting knowledge, attitude and stress. It was apparent that the Family-Focused Education Programme enhanced parental competence. Undoubtedly, the family-focused approach is crucial for enhancing parenting competency, and education is fundamental to enabling parents.
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Chan KW, Siu CK, Wong SY, Liu ZF. The elimination of a hydrogen atom in Na(H2O)n. J Chem Phys 2005; 123:124313. [PMID: 16392488 DOI: 10.1063/1.2035076] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
By a systematic examination on Na(H2O)n, with n = 4-7, 9, 10, and 15, we demonstrate that a hydrogen loss reaction can be initiated by a single sodium atom with water molecules. This reaction is similar to the well-known size-dependent intracluster hydrogen loss in Mg+(H2O)n, which is isoelectronic to Na(H2O)n. However, with one less charge on Na(H2O)n than that on Mg+(H2O)n, the hydrogen loss for Na(H2O)n is characterized by a higher barrier and a more flexible solvation shell around the metal ion, although the reaction should be accessible, as the lowest barrier is around 8 kcal/mol. Interestingly, the hydroxide ion OH- produced in the process is stabilized by the solvation of H2O molecules and the formation of an ion pair Na+(H2O)4(H2O)n-l-4[OH-(H2O)l]. The activation barrier is reduced as the unpaired electron in Na(H2O)n moves to higher solvation shells with increasing cluster size, and the reaction is not switched off for larger clusters. This is in sharp contrast to the reaction for Mg+(H2O)n, in which the OH- ion is stabilized by direct coordination with Mg2+ and the reaction is switched off for n > 17, as the unpaired electron moved to higher solvation shells. Such a contrast illustrates the important link between microsolvation environment and chemical reactivity in solvation clusters.
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Wong SY, Lim WWC, Que TL, Au DMY. Reflection on SARS precautions in a severe intellectual disabilities hospital in Hong Kong. JOURNAL OF INTELLECTUAL DISABILITY RESEARCH : JIDR 2005; 49:379-384. [PMID: 15817055 PMCID: PMC7167173 DOI: 10.1111/j.1365-2788.2005.00687.x] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Accepted: 10/13/2004] [Indexed: 05/24/2023]
Abstract
BACKGROUND Hong Kong went through a battle with a new respiratory disease, severe acute respiratory syndrome (SARS), from March to June 2003. All clinical settings, including rehabilitative and infirmary setting, have actively involved in fighting against the infection. The intent of this paper was to reflect on the SARS precautionary measures that had been taken in a severe intellectual disabilities hospital in Hong Kong. METHODS A review on six SARS precautionary measures were conducted. They were assessment of risk, formulation of operational guidelines, implementation of infection control measures, education and training of staff, conducting audits and carrying out environmental improvement work. RESULTS Patients were at risk of getting infected from carers, visitors, volunteers, and staff and patients of general hospitals. A SARS Quarantine Unit, isolation ward, was opened to isolate patients who might have had close contact with SARS patients during a stay in a general hospital or when they returned from home leave. Undoubtedly, both staff and relatives participated in preventing the patients from being infected. No day leave and home leave was reported and the number of hospitalization in general hospital was decreased during the critical period. Three infection control audits were conducted and improvement work was carried out subsequently. CONCLUSION The practice of grouping within a standard isolation room is recommended to continue in the future. Moreover, intensive infection control training for all staff is of highest importance to safeguard the health of both staff and patient.
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Wong SY, Lau EM, Lau WW, Lynn HS. Is dietary counselling effective in increasing dietary calcium, protein and energy intake in patients with osteoporotic fractures? A randomized controlled clinical trial. J Hum Nutr Diet 2004; 17:359-64. [PMID: 15250845 DOI: 10.1111/j.1365-277x.2004.00536.x] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
To determine the feasibility of increasing the calcium, protein and calorie intake of osteoporotic fracture patients by repeated dietary counselling delivered by a dietitian, a randomized controlled trial was conducted. Among 189 patients presenting with osteoporotic fractures to an Orthopaedics and Traumatology Department of a large regional hospital, 98 patients were randomized to the intervention group and 91 were randomized to the control group (with usual care). Intervention group received three sessions of dietary counselling with tailored made recommendations over a period of 4 months, while the control group only received dietary assessment and pamphlets on the prevention of osteoporosis. Almost all subjects in both intervention and control groups had calcium intake below the recommended level of 1000 mg at baseline. Half and 60% of subjects in both groups had total energy and protein intake below recommended levels respectively. The mean weights of control and intervention groups at baseline were 51.5 and 50.9 kg respectively, while the body mass index (BMI) were 22.6 (kg m(-2)) and 22.6 (kg m(-2)) respectively. After dietary intervention, significant increase of intake was seen in calcium intake (P = 0.0095 by t-test) in the intervention group. No significant increase was seen in protein or calorie intake. No significant change was observed in the body weight or BMI although there was a positive trend in the intervention group for all these parameters. We concluded that there was general malnutrition in Chinese elderly who presented with osteoporotic fractures. Dietary calcium could be increased by repeated professional dietary counselling. Future studies with longer duration and more objective clinical outcomes will be helpful to further demonstrate the long-term effects of dietary intervention on osteoporosis and other chronic diseases.
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Ng FH, Wong SY, Chang CM, Chen WH, Kng C, Lanas AI, Wong BCY. High incidence of clopidogrel-associated gastrointestinal bleeding in patients with previous peptic ulcer disease. Aliment Pharmacol Ther 2003; 18:443-9. [PMID: 12940930 DOI: 10.1046/j.1365-2036.2003.01693.x] [Citation(s) in RCA: 80] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
BACKGROUND In average-risk patients, the new anti-platelet agent, clopidogrel, causes less upper gastrointestinal adverse events than aspirin. However, there are no safety data on the use of clopidogrel in high-risk patients. AIM To evaluate the safety of clopidogrel in patients with peptic ulcer disease in a retrospective cohort longitudinal study. METHODS During the period from January 2000 to May 2002, 70 patients who were prescribed clopidogrel (75 mg/day) for a previous history of non-aspirin-related peptic ulcer disease or a history of aspirin-related gastrointestinal complications (dyspepsia or peptic ulcer) were recruited. The occurrence of ulcer complications (bleeding/perforation/obstruction) was the primary end-point. RESULTS After a median follow-up of 1 year, nine patients (12%) developed gastrointestinal bleeding and one had a perforated peptic ulcer. Clopidogrel-associated gastrointestinal bleeding was significantly more common in patients with a history of gastrointestinal bleeding than in those without (22% vs. 0%; P = 0.007; odds ratio, 1.3; 95% confidence interval, 1.1-1.5). CONCLUSIONS Clopidogrel is associated with a high incidence of upper gastrointestinal bleeding in high-risk patients. A previous history of gastrointestinal bleeding appears to be a predictor of adverse gastrointestinal events.
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Ng FH, Wong WM, Wong BCY, Kng C, Wong SY, Lai KC, Cheng CS, Yuen WC, Lam SK, Lai CL. Sequential intravenous/oral antibiotic vs. continuous intravenous antibiotic in the treatment of pyogenic liver abscess. Aliment Pharmacol Ther 2002; 16:1083-90. [PMID: 12030949 DOI: 10.1046/j.1365-2036.2002.01266.x] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
AIM Pyogenic liver abscesses result in substantial morbidity and mortality. Antimicrobial regimens using sequential intravenous/oral therapy may reduce the length of hospital stay. In this retrospective analysis, the efficacy of continuous intravenous antibiotic therapy (group I) vs. sequential intravenous/oral antibiotic therapy (group II) was studied in patients with pyogenic liver abscess. METHODS One hundred and twelve consecutive patients (55 in group I and 57 in group II) with pyogenic liver abscess were analysed. Clinical response, length of hospital stay and relapse rates were examined. RESULTS Group II had a significantly shorter duration of intravenous antibiotic treatment (3.2 weeks vs. 5.9 weeks, P < 0.01) and a shorter length of hospital stay (28 days vs. 42 days, P < 0.01) when compared to group I. Oral antibiotics were prescribed for a median duration of 2.9 weeks in group II after discharge. No relapse occurred within 6 weeks after the completion of treatment in both groups. The cost of therapy was significantly lower in group II than in group I by 33%. CONCLUSIONS A sequential intravenous/oral antibiotic regime is a safe and effective treatment for pyogenic liver abscess. This reduces the cost of therapy and the length of hospital stay.
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Wong SY, Lam MS. Rickettsioses: the new and old diseases. Singapore Med J 2001; 42:546-8. [PMID: 11989573] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/24/2023]
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Xia HH, Wong BC, Wong KW, Wong SY, Wong WM, Lai KC, Hu WH, Chan CK, Lam SK. Clinical and endoscopic characteristics of non-Helicobacter pylori, non-NSAID duodenal ulcers: a long-term prospective study. Aliment Pharmacol Ther 2001; 15:1875-82. [PMID: 11736717 DOI: 10.1046/j.1365-2036.2001.01115.x] [Citation(s) in RCA: 36] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
BACKGROUND The proportion of duodenal ulcers not associated with Helicobacter pylori infection or the use of non-steroidal anti-inflammatory drugs (NSAIDs) is increasing. AIM To identify the clinical and endoscopic characteristics of non-H. pylori, non-NSAID duodenal ulcers. METHODS Clinical and endoscopic data and H. pylori status were prospectively collected from consecutive patients who underwent upper endoscopy from 1997 to 1999. Patients with duodenal ulcers were identified, and those with non-H. pylori, non-NSAID duodenal ulcers were analysed further. RESULTS A total of 11 717 upper endoscopies were performed in 8344 patients. Of these, 1153 (14%) had duodenal ulcers. Of 599 patients with active ulcers and known H. pylori status, 104 (17%) had ulcers not associated with H. pylori or the use of NSAIDs, 393 (66%) had ulcers associated with H. pylori alone, 51 (8.5%) had ulcers associated with the use of NSAIDs alone and 51 (8.5%) had ulcers associated with both. Multivariate logistic regression analysis revealed that the presence of concomitant diseases (odds ratio=15.0; 95% confidence interval, 8.64-25.9; P < 0.001) and the absence of epigastric pain/discomfort (odds ratio=0.52; 95% confidence interval, 0.29-0.91; P=0.022) were independent predictors for non-H. pylori, non-NSAID duodenal ulcers. CONCLUSIONS Non-H. pylori, non-NSAID duodenal ulcers exhibit certain distinct clinical and endoscopic characteristics. The presence of concomitant diseases is an important predictive factor.
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Ng FH, Cheung TC, Chow KC, Wong SY, Ng WF, Chan HC, Chau WK, Chang CM. Repeated intestinal perforation caused by an incomplete form of Behçet's syndrome. J Gastroenterol Hepatol 2001; 16:935-9. [PMID: 11555112 DOI: 10.1046/j.1440-1746.2001.02423.x] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/09/2022]
Abstract
Behçet's disease, as initially described, is a triad of recurrent oral and genital ulcers and relapsing uveitis. The incomplete form, in which there is no ocular involvement, has been described in Japan and Korea, but this is not commonly recognized in the southern Chinese. We reported herein a rare case of repeated intestinal perforations caused by an incomplete form of Behçet's syndrome in a southern Chinese man.
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Lee AS, Teo AS, Wong SY. Novel mutations in ndh in isoniazid-resistant Mycobacterium tuberculosis isolates. Antimicrob Agents Chemother 2001; 45:2157-9. [PMID: 11408244 PMCID: PMC90621 DOI: 10.1128/aac.45.7.2157-2159.2001] [Citation(s) in RCA: 107] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Novel mutations in NADH dehydrogenase (ndh) were detected in 8 of 84 (9.5%) isoniazid (INH)-resistant isolates (T110A [n = 1], R268H [n = 7]), but not in 22 INH-susceptible isolates of Mycobacterium tuberculosis. Significantly, all eight isolates with mutations at ndh did not have mutations at katG, kasA, or the promoter regions of inhA or ahpC, except for one isolate. Mutations in ndh appear to be an additional molecular mechanism for isoniazid resistance in M. tuberculosis.
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Skelton V, Greenway GM, Haswell SJ, Styring P, Morgan DO, Warrington BH, Wong SY. The generation of concentration gradients using electroosmotic flow in micro reactors allowing stereoselective chemical synthesis. Analyst 2001; 126:11-3. [PMID: 11205499 DOI: 10.1039/b006727j] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The stereoselective control of chemical reactions has been achieved by applying electrical fields in a micro reactor generating controlled concentration gradients of the reagent streams. The chemistry based upon well-established Wittig synthesis was carried out in a micro reactor device fabricated in borosilicate glass using photolithographic and wet etching techniques. The selectivity of the cis (Z) to trans (E) isomeric ratio in the product synthesised was controlled by varying the applied voltages to the reagent reservoirs within the micro reactor. This subsequently altered the relative reagent concentrations within the device resulting in Z/E ratios in the range 0.57-5.21. By comparison, a traditional batch method based on the same reaction length, concentration, solvent and stoichiometry (i.e., 1.0:1.5:1.0 reagent ratios) gave a Z/E in the range 2.8-3.0. However, when the stoichiometric ratios were varied up to ten times as much, the Z/E ratios varied in accordance to the micro reactor i.e., when the aldehyde is in excess, the Z isomer predominates whereas when the aldehyde is in low concentrations, the E isomer is the more favourable form. Thus indicating that localised concentration gradients generated by careful flow control due to the diffusion limited non-turbulent mixing regime within a micro reactor, leads to the observed stereo selectivity for the cis and trans isomers.
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Skelton V, Greenway GM, Haswell SJ, Styring P, Morgan DO, Warrington B, Wong SY. The preparation of a series of nitrostilbene ester compounds using micro reactor technology. Analyst 2001; 126:7-10. [PMID: 11205516 DOI: 10.1039/b006728h] [Citation(s) in RCA: 46] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The synthesis of stilbene esters using Wittig chemistry has been used to illustrate the generic diversity micro reactors offer in terms of chemical control and rapid method development. The micro reactor consisted of a 'T' design based on channel geometries 200 microns wide and 100 microns deep, etched into borosilicate glass and sealed with a borosilicate top plate using a thermal bonding technique. The movement of the reagent and products was achieved using electroosmotic flow (EOF), assisted by the incorporation of micro porous silica frits within the micro-channels to allow accurate solution control. To optimise the operating conditions methyl 4-formylbenzoate, premixed with sodium methoxide, was reacted with 2-nitrobenzyl-triphenylphosphonium bromide in dry degassed MeOH using flow conditions for both reagents of 0.40 microL min-1 for 20 min. A product yield of 70% (2:1 reaction stoichiometry with the aldehyde in excess) was obtained representing a 10% increase compared with the traditional batch synthesis. To demonstrate the capability of micro reactors to perform atom efficient synthesis a series of experiments based on an injection methodology (optimised to 30 s) were performed in the micro reactor at 1:1 stoichiometry resulting in a yield of 59%. Finally, the capability of micro reactors to perform a series of analogue reactions was investigated. The yields for a further three aldehydes indicated that the technology will be suitable for the development of automated device to support the generation of combinatorial libraries and rapid high throughput synthetic methods.
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Ng FH, Kng C, Wong SY, Yuen WC, Mau TY. Positioning the rubber band at the tip of the housing cylinder can prevent damage to the gastroscope during endoscopic variceal ligation. Endoscopy 2000; 32:S61. [PMID: 11068845] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/10/2022]
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Sawyer MA, Lim RB, Wong SY, Cirangle PT, Birkmire-Peters D. Telementored laparoscopic cholecystectomy: a pilot study. Stud Health Technol Inform 2000; 70:302-8. [PMID: 10977561] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/17/2023]
Abstract
Few laparoscopic surgical experts exist relative to the number of surgeons needing training in laparoscopic surgical techniques. This study tested application of telemedicine technology in the mentoring of surgeons during laparoscopic cholecystectomy. Our Surgical Telementoring Suite provided real-time audio and video telecommunication to the operating room. Data points for telementored laparoscopic cholecystectomy (TLC, n = 6) were compared to age and sex-matched controls having standard laparoscopic cholecystectomy (SLC, n = 6) with mentors physically present in the operating room. TLC data were also compared between cases performed with a staff surgeon and resident as mentorees (SRM, n = 3), versus two residents as mentorees (RRM, n = 3). Data were analyzed with chi-square testing. The level of statistical significance was set at p < 0.05. No major operative complications occurred in either group (p > 0.05). Total operative times were similar (92.2 +/- 18.4 minutes SLC vs. 94.7 +/- 25.3 minutes TLC, p > 0.05). Additional data compared between SRM and RRM groups included time to establishment of a pneumoperitoneum of 12-15 mm Hg (7.0 +/- 6.1 minutes SRM vs. 6.7 +/- 2.9 minutes RRM), time to placement of all four trocars (13.0 +/- 3.6 minutes SRM vs. 10.3 +/- 3.1 minutes RRM, time to isolation and proximal clipping of the cystic duct (38.0 +/- 12.1 minutes SRM vs. 55.7 +/- 29.0 minutes RRM), and time to removal of the gallbladder (77.3 +/- 25.4 minutes vs. 77.7 +/- 27.5 minutes RRM). For all data points, p > 0.05. We conclude that telementoring is a safe, effective method for teaching the techniques of LC. This is true for operating teams composed of surgical residents, with or without staff surgeons present.
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Abstract
Unbuffered rapid urease test (RUT) is an accurate, rapid, and inexpensive method of detecting Helicobacter pylori. However, it is generally recommended to prepare the reagent daily. This prospective study was undertaken to evaluate the shelf-life of our unbuffered RUT at -20 degrees C. Two sets of antral biopsies (X2) and body biopsies (X1) were taken from all patients. They were subjected to histologic examination and RUT stored at -20 degrees C. We studied 303 patients. One hundred seventy-nine (59%) were infected as defined by histologic examination. The reagent was classified according to the storage time (group I, 0-30 days [n = 109]; group II, 31-60 days [n = 63]; group III, 61-90 days [n = 80]; and group IV, tau91 days [n = 51]). There was an excellent agreement between the histologic examination and the RUT of the four groups (kappa coefficient: group I, 0.88; group III, 0.80; group III, 0.87; group IV, 0.88). The sensitivity of our RUT in groups I, II, III, and IV were 92%, 92%, 91%, and 89%, respectively. The corresponding specificity were 97%, 88%, 97%, and 100%. Our RUT remains highly sensitive and specific when it is stored at -20 degrees C for 4 months.
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Teong HH, Leo YS, Wong SY, Sng LH, Ding ZP. Case report of Staphylococcus lugdunensis native valve endocarditis and review of the literature. ANNALS OF THE ACADEMY OF MEDICINE, SINGAPORE 2000; 29:673-7. [PMID: 11126708] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/18/2023]
Abstract
INTRODUCTION Coagulase-negative staphylococci, commonly Staphylococcus epidermidis, cause 5% of native valve endocarditis. We describe a case due to Staphylococcus lugdunensis, a coagulase-negative staphylococcus identified in 1988, as a first report in Southeast Asia. It was previously misidentified as S. aureus because it is sometimes slide coagulase positive, but always tube coagulase negative, resulting in its delayed recognition as a pathogen. We also reviewed 36 other cases reported in the English literature from 1988 to 1999. CLINICAL PICTURE Our patient was admitted 3 times over 4 months for unresolved weight loss and fever before the coagulase-negative staphylococcus bacteraemia was eventually considered significant. TREATMENT AND OUTCOME He was treated with 4 weeks of high-dose intravenous penicillin and 2 weeks of gentamicin and did not require urgent valve replacement. CONCLUSION A positive blood culture of coagulase-negative staphylococcus is not always a contaminant. S. lugdunensis can cause aggressive native valve endocarditis resulting in high mortality, especially without surgical intervention.
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Ling AE, Robbins KE, Brown TM, Dunmire V, Thoe SY, Wong SY, Leo YS, Teo D, Gallarda J, Phelps B, Chamberland ME, Busch MP, Folks TM, Kalish ML. Failure of routine HIV-1 tests in a case involving transmission with preseroconversion blood components during the infectious window period. JAMA 2000; 284:210-4. [PMID: 10889595 DOI: 10.1001/jama.284.2.210] [Citation(s) in RCA: 83] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/14/2022]
Abstract
CONTEXT Current screening practices for blood donations have been successful in reducing human immunodeficiency virus (HIV) transmission through receipt of contaminated blood products. However, HIV-infected blood donations made prior to seroconversion and before high levels of viral replication occur could test negative using both serologic antigen and antibody tests. Testing based on nucleic acid amplification (NAT) is being implemented to screen for HIV-infected blood donated during this period, yet the issue of single vs minipool donation screening remains unresolved. OBJECTIVES To determine HIV-1 genetic linkage between virus in 2 HIV-1-infected recipients of blood components and virus in the donor, who was HIV antigen and antibody negative at the time of donation; to screen the blood donor's plasma with HIV NAT assays, including those currently proposed for use in US blood donation screening. DESIGN AND SETTING Case study conducted in October 1997 involving the Communicable Disease Centre, Singapore General Hospital, and the Singapore Blood Transfusion Service, Singapore. SUBJECTS The blood donor and the 2 recipients of donor platelets and red blood cells. MAIN OUTCOME MEASURES Genetic analysis of the HIV-1 p17 coding region of gag and the C2V5 region of env to determine the genetic relatedness of virus from the donor and recipients; reactivity in quantitative and qualitative assays, and reactivity in donor screening HIV NAT assays in single donation and minipool screening contexts. RESULTS Direct DNA sequencing demonstrated identical HIV-1 subtype E viral sequences in the donor and recipients. Based on comparisons of a qualitative and quantitative assay for HIV-1 RNA levels, a low level of viremia (range, 5-39 copies/mL in plasma) was estimated to be in the donor's undiluted blood at the time of donation. Additional testing using donor-screening NAT assays showed consistent detection of HIV RNA in the undiluted donor plasma whereas detection was inconsistent at the 1:16 and 1:24 dilution levels currently used in minipool screening of blood donations in the United States. CONCLUSIONS Transmission of HIV from a blood donor to a platelet recipient and a red blood cell recipient occurred in the preseroconversion infectious window period. The viral load in the implicated donation was estimated to be less than 40 copies/mL of plasma. Current US minipool HIV NAT screening protocols may not be sufficiently sensitive to detect all infectious window-period donations. JAMA. 2000;284:210-214
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Yeo KK, Yeo TT, Chan CY, Sitoh YY, Teo J, Wong SY. Stereotactic brain biopsies in AIDS patients--early local experience. Singapore Med J 2000; 41:161-6. [PMID: 11063180] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/18/2023]
Abstract
AIM To assess the usefulness of stereotactic brain biopsies in AIDS patients with cerebral lesions in Singapore. METHODS A total of 10 patients with AIDS and cerebral lesions underwent stereotactic brain biopsies in the Department of Neurosurgery, Tan Tock Seng Hospital (TTSH) between September 1997 and September 1998. The patients were referred from the Communicable Diseases Centre (CDC), TTSH. These patients either failed a trial of therapy for toxoplasmosis encephalitis (TE) or had CT/MRI scans which did not suggest TE. Four were CT-guided and six were MRI-guided stereotactic biopsies. The Radionics Cosman-Robert-Wells (CRW) stereotactic apparatus was used for all cases. RESULTS The male to female ratio was 9:1. Histological diagnosis from biopsy was lymphoma (5), metastatic adenocarcinoma (1), TE (1), abscess (1), encephalitis (1) and granulomatous tissue (1-presumed tuberculosis). CONCLUSION The early experience is that stereotactic brain biopsy is useful in patients with AIDS and cerebral lesions. The etiology is confirmed in the majority of cases and impacts on management decisions and prognostication.
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Park JY, Danko GP, Wong SY, Weatherspoon AJ, Johnson RC. Religious affiliation, religious involvement, and alcohol use in Korea. CULTURAL DIVERSITY AND MENTAL HEALTH 2000; 4:291-6. [PMID: 9818517] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Subscribe] [Scholar Register] [Indexed: 02/09/2023]
Abstract
This article is the first study of religious commitment and involvement of homeland Koreans as related to alcohol use. Religious affiliation and involvement are predictive of abstemiousness, but chiefly for women, who are at low risk for alcohol abuse and dependency, and not for men, who are at high risk. The frequent abstemiousness of Buddhist women results chiefly from data having to do with mothers and probably is a consequence of the women's traditional lifestyles, being both Buddhist and abstemious. Among the probably more Westernized Christians, religious involvement is most clearly associated with abstemiousness among daughters, a group at a relatively low but increasing risk for alcohol use.
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