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Tan JL, Luo GX. [Pay attention to burn rehabilitation assessment]. Zhonghua Shao Shang Yu Chuang Mian Xiu Fu Za Zhi 2023; 39:1109-1114. [PMID: 38129296 DOI: 10.3760/cma.j.cn501225-20230831-00070] [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] [Grants] [Subscribe] [Scholar Register] [Indexed: 12/23/2023]
Abstract
With the vigorous development of burn rehabilitation, many burn units in China are paying more and more attention to the application of burn rehabilitation treatment methods in burn patients. However, the development of burn rehabilitation assessment cannot be ignored in the process of burn rehabilitation treatment. Burn rehabilitation assessment is characterized with a long assessment time span and a large and complex assessment contents, resulting in the inability to develop a standardized assessment form that is suitable for all burn patients. In addition, factors including the shortage of professionals in burn rehabilitation assessment in some domestic burn units, relatively small number of objective assessment instruments and various institutional limitations, have also led to insufficient motivation and low quality of burn rehabilitation assessment. Based on those, this article analyzes the characteristics and main contents of burn rehabilitation assessment in China, and puts forward some suggestions in view of the shortcomings of burn rehabilitation assessment, in order to provide a reference for burn rehabilitation practitioners.
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Affiliation(s)
- J L Tan
- Institute of Burn Research, State Key Laboratory of Trauma and Chemical Poisoning, the First Affiliated Hospital of Army Medical University (the Third Military Medical University), Chongqing 400038, China
| | - G X Luo
- Institute of Burn Research, State Key Laboratory of Trauma and Chemical Poisoning, the First Affiliated Hospital of Army Medical University (the Third Military Medical University), Chongqing 400038, China
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Tan JL, Sidhu-Brar S, Woodman R, Chinnaratha MA. Regular Aspirin Use Is Associated with a Reduced Risk of Hepatocellular Carcinoma (HCC) in Chronic Liver Disease: a Systematic Review and Meta-analysis. J Gastrointest Cancer 2023; 54:325-331. [PMID: 35717551 DOI: 10.1007/s12029-022-00842-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 06/08/2022] [Indexed: 10/18/2022]
Abstract
PURPOSE Aspirin reduces the incidence of various gastrointestinal (GI) malignancies. This meta-analysis assessed the efficacy and safety of regular aspirin use on the incidence of hepatocellular carcinoma (HCC) in patients with chronic liver disease. METHODS Electronic reference databases were searched for studies in patients with chronic liver disease exposed to aspirin. The primary outcome was the incidence of HCC in regular aspirin users compared to non-users. The secondary outcome was the incidence of major GI bleeding events in both groups. The propensity score (PS) and non-PS-adjusted pooled hazard ratio (HR) were calculated using random-effects models. RESULTS Six observational studies with 71,211 subjects were included. The median duration of follow-up ranged from 2.7 to 7.9 years. Four studies included patients with viral hepatitis; five studies used aspirin 100 mg/day. All six studies reported the non-PS-matched HR, and there was a 54% reduction in the incidence of HCC among regular aspirin users [HR (95% CI): 0.46(0.31-0.67), p < 0.001]. Four studies reported on the PS-matched HR; this showed a 46% reduced incidence of HCC in those using aspirin [HR (95% CI): 0.54(0.38-0.79), p < 0.001]. Subgroup analysis on studies restricted to viral hepatitis (n = 4) showed a 28% reduction in HCC incidence in aspirin users [HR (95% CI): 0.72(0.64-0.80), p < 0.001]. Four studies reported the incidence of major GI bleeds, there was no significant difference between the two groups [HR (95% CI: 1.00(0.69-1.45), p = 0.90]. All outcome analysis, except the subgroup analysis, had significant inter-study heterogeneity. CONCLUSION Regular aspirin use in chronic liver disease is associated with reduced incidence of HCC without increasing the risk of major GI bleeding.
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Affiliation(s)
- Jin Lin Tan
- Division of Medicine, Lyell McEwin Hospital, Haydown Road, Elizabeth Vale, SA, 5112, Australia.
| | - Sandeep Sidhu-Brar
- Division of Medicine, Lyell McEwin Hospital, Haydown Road, Elizabeth Vale, SA, 5112, Australia
| | - Richard Woodman
- Flinders Centre for Epidemiology and Biostatistics, Flinders University, Sturt Rd, Bedford Park, SA, 5042, Australia
| | - Mohamed Asif Chinnaratha
- Department of Gastroenterology/Hepatology, Lyell McEwin Hospital, Haydown Road, Elizabeth Vale, SA, 5112, Australia
- Faculty of Health and Medical Sciences, The University of Adelaide, Adelaide, SA, 5005, Australia
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Ling WY, Loo CH, Nurul Shafaril Niza MA, Tan JL, Norazlima MA, Tan WC. The effect of medical education and counselling on treatment adherence and disease severity in patients with acne vulgaris: a non-randomised interventional study. Med J Malaysia 2023; 78:263-269. [PMID: 37271834] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
INTRODUCTION Acne vulgaris (AV) is a common inflammatory skin disease affecting adolescents and young adults. It affects one's self-esteem and social relationship. In addition, poor adherence to treatment can cause poor treatment response and disease recurrence. This study aims to determine the effectiveness of medical education and counselling on treatment adherence and disease severity. METHODS This is a non-randomised interventional study with age- and treatment- matched control conducted in a tertiary dermatology clinic from July 2021 to June 2022. Patients in the intervention group received a 10 min video presentation on acne, followed by treatment counselling. The adherence rate was determined objectively (pill counting and tube weighing) and subjectively (ECOB questionnaire). The disease severity was assessed using the Comprehensive Acne Severity Scale (CASS) and Global Acne Grading System (GAGS). RESULTS A total of 100 patients completed the 12-week study. With intervention, patients have better adherence to topical medication (5% benzoyl peroxide gel: 71% vs 57.9%, p= 0.031; 0.05% tretinoin cream: 58.7% vs 45.4%, p= 0.044) at week 12. However, the intervention program did not improve adherence to oral medication. Overall, with intervention, a significantly higher percentage of improvement in disease severity was noted (47.3% vs. 39.1%, p=0.044). Nonadherence to treatment was attributed mostly to forgetfulness in 54% of the patients, followed by a busy lifestyle (41%) and little knowledge of acne (26%). CONCLUSION Patients have significantly better adherence to topical medication with education and counselling. Better adherence to treatment leads to more remarkable disease improvement.
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Affiliation(s)
- W Y Ling
- Hospital Pulau Pinang, Department of Dermatology, Penang, Malaysia.
| | - C H Loo
- Hospital Pulau Pinang, Department of Dermatology, Penang, Malaysia
| | | | - J L Tan
- Hospital Pulau Pinang, Department of Pharmacy, Penang, Malaysia
| | - M A Norazlima
- Hospital Pulau Pinang, Department of Dermatology, Penang, Malaysia
| | - W C Tan
- Hospital Pulau Pinang, Department of Dermatology, Penang, Malaysia
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Yuan SM, Tang YR, Peng YL, Tan JL. [Effects of three methods for correction of low-degree against-the-rule corneal astigmatism during cataract surgery]. Zhonghua Yan Ke Za Zhi 2023; 59:110-117. [PMID: 36740440 DOI: 10.3760/cma.j.cn112142-20220401-00152] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Objective: To compare the clinical effects of and visual quality after correction of low-degree against-the-rule (ATR) corneal astigmatism by implantation of an astigmatism-corrected intraocular lens (IOL), femtosecond laser release and manual release in cataract surgery. Methods: It was a prospective cohort study. A total of 120 patients (120 eyes) with cataract combined with low-degree ATR corneal astigmatism diagnosed in Chongqing Aier Mega Eye Hospital from December 2017 to October 2020 were included and divided into 3 groups, each with 40 patients, according to their own selections of astigmatism correction methods during cataract surgery. In the astigmatism-corrected IOL group, phacoemulsification for cataract extraction combined with toric IOL implantation was performed. In the femtosecond laser release group, astigmatic keratotomy using a femtosecond laser was combined. In the manual release group, a limbal relaxing incision was made. Uncorrected distance visual acuity (UDVA) and corneal astigmatism were measured before surgery. At 3 months and 1 year after surgery, UDVA and best-corrected distance visual acuity were examined, as well as whole eye residual astigmatism by ARK-1, corneal astigmatism by the IOLMaster 500, whole eye high order aberration (HOA) and modulation transfer function (MTF) by the iTrace visual function analyzer. Analysis of variance was used for the comparison of data in a normal distribution. Repeated measures were used for the comparison within groups. The rank sum test was used for the comparison of data that were not normally distributed. Results: Of the 120 patients, 100 patients (100 eyes), including 44 males and 56 females, with an age of (66.48±6.20) years, completed the follow-up. Among the three groups, the differences were not statistically significant in terms of gender distribution, age, preoperative corneal astigmatism, UDVA and spherical equivalent of the IOL (all P>0.05). At 3 months and 1 year after surgery, the UDVA was significantly better than that before surgery in each group (Z=5.18, 5.04, 4.98, 4.99, 4.90, 4.89; all P<0.001). At the two time points, the differences in the whole eye residual astigmatism among the three groups were statistically significant (H=30.69, 31.23; both P<0.001). At 3 months, the whole eye residual astigmatism in the astigmatism-corrected IOL group was lower than that in the other two groups. At 1 year, the residual astigmatism in the astigmatism-corrected IOL group [0.25(0.00, 0.50) D] was also lower compared to that in the femtosecond laser release group [0.50(0.50, 0.75) D] and the manual release group [0.75(0.50, 0.75) D] (Z=-3.71, -5.18, -3.94, -5.15; all P<0.001). The differences in the HOA at 3 months and 1 year among the three groups were statistically significant (H=36.30, 34.38; both P<0.001). The HOA in the astigmatism-corrected IOL group was significantly higher than that in the other two groups at the two time points (Z=5.01, 4.73, 5.31, 5.27; all P<0.001). At 3 months and 1 year, the differences in the MTF value among the three groups were also statistically significant (H=30.02, 29.92; both P<0.001), and the MTF value in the femtosecond laser release group was significantly higher than that in the other two groups (Z=4.61, 4.67, 4.66, 4.69; all P<0.001). Conclusions: All the three astigmatism correction methods used at the time of cataract surgery can effectively correct low-degree ATR corneal astigmatism. The residual astigmatism in the whole eye after astigmatism-corrected IOL implantation is small and stable, while the HOA after release using the femtosecond laser is low with good visual quality.
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Affiliation(s)
- S M Yuan
- Chongqing Aier Mega Eye Hospital, Chongqing 400020, China
| | - Y R Tang
- Chongqing Aier Mega Eye Hospital, Chongqing 400020, China
| | - Y L Peng
- Chongqing Eye Hospital, Chongqing 400020, China
| | - J L Tan
- Chongqing Eye Hospital, Chongqing 400020, China
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Loo G, Yap J, Hon JS, Ismail A, Lim CL, Sumanthy P, Ruan W, Sewa DW, Phua GC, Ng SA, Hong C, Low A, Lim ST, Tan JL. Real-world outcomes of Selexipag for treatment of pulmonary hypertension in an Asian population. Eur Heart J 2023. [DOI: 10.1093/eurheartj/ehac779.081] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/26/2023] Open
Abstract
Abstract
Funding Acknowledgements
Type of funding sources: None.
Introduction
Selexipag is an oral selective prostacyclin IP receptor agonist indicated for treatment of pulmonary arterial hypertension (PAH). Data on its real-world safety and efficacy in Asians is lacking.
Purpose
We sought to evaluate the clinical characteristics, treatment regimens and outcomes of patients initiated on selexipag in a tertiary cardiac centre in Asia.
Methods
This was a retrospective study on all patients initiated on selexipag from January 2017 to December 2020. Baseline and follow up characteristics including demographics, functional status and clinical data were collected. Clinical outcomes evaluated included hospitalisation for PH related complications and all-cause mortality. Patients were risk stratified using the COMPERA 2.0 risk scores.
Results
A total of 36 PAH patients were treated with selexipag. At baseline, most patients were WHO functional class II or III (36.4% and 51.5% respectively), with a NT-proBNP of 1335 pg/ml (557 – 2918) and 6 minute walk test (6MWT) duration of 327.5 ±126.4 meters. Selexipag was initiated at 200mcg twice daily dosage for all except one patient (started at 200mcg once daily) and the maximum tolerated dose ranged from 200mcg twice daily to 1400mcg twice daily, with majority tolerating up to a dose of 600mcg twice daily (58.3%). Side effects were reported in 23 patients (63.9%), of which headache (27.8%), diarrhea (30.6%) or musculoskeletal symptoms (27.8%) were predominant. After a median follow up duration of 25.9 ± 23.1 months, selexipag was stopped in 20 patients (55.6%), of which eight patients were due to PAH progression requiring alternative therapy, and 12 patients due to side effects from selexipag. At baseline, patients were classified into low (8.3%), intermediate-low (30.6%), intermediate-high (33.3%) and high risk (27.8%) respectively. Patients who continued on selexipag at follow up showed no change (46.2%), improvement (15.4%) and deterioration (38.5%) in risk score. In the overall cohort of 36 patients, majority (75%) had at least one hospitalisation for PAH related complications and 15 patients (41.7%) demised.
Conclusion
In this real-world study, while selexipag was associated with a stable or improved PAH risk scores in majority of patients, there was a subset of patients with disease progression or intolerance to the medication. Further studies are warranted to identify patients who will benefit most from this therapy.
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Affiliation(s)
- G Loo
- National Heart Centre Singapore , Singapore , Singapore
| | - J Yap
- National Heart Centre Singapore , Singapore , Singapore
| | - J S Hon
- National Heart Centre Singapore , Singapore , Singapore
| | - A Ismail
- National Heart Centre Singapore , Singapore , Singapore
| | - C L Lim
- National Heart Centre Singapore , Singapore , Singapore
| | - P Sumanthy
- National Heart Centre Singapore , Singapore , Singapore
| | - W Ruan
- National Heart Centre Singapore , Singapore , Singapore
| | - D W Sewa
- Singapore General Hospital , Singapore , Singapore
| | - G C Phua
- Singapore General Hospital , Singapore , Singapore
| | - S A Ng
- Singapore General Hospital , Singapore , Singapore
| | - C Hong
- Singapore General Hospital , Singapore , Singapore
| | - A Low
- Singapore General Hospital , Singapore , Singapore
| | - S T Lim
- National Heart Centre Singapore , Singapore , Singapore
| | - J L Tan
- National Heart Centre Singapore , Singapore , Singapore
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Fu QQ, Li MJ, Huang L, Tan JL, Zhou YQ, Li N. [Clinical application effect of sequential nursing on the management of new skin on face and neck after deep burns]. Zhonghua Shao Shang Yu Chuang Mian Xiu Fu Za Zhi 2022; 38:952-958. [PMID: 36299207 DOI: 10.3760/cma.j.cn501120-20210323-00101] [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] [Grants] [Subscribe] [Scholar Register] [Indexed: 06/16/2023]
Abstract
Objective: To explore the clinical application effect of sequential nursing on the management of new skin on face and neck after deep burns. Methods: The retrospective case-control research approach was used. From January to December 2019, 109 patients who met the inclusion criteria were admitted to the First Affiliated Hospital of Army Medical University (the Third Military Medical University) within 1 week after deep burn wound healing on the face and neck. Fifty-five patients who were admitted to the hospital from January to June and received comprehensive treatment and conventional nursing were included in conventional nursing group (27 males and 28 females, aged 21-65 (40±17) years), and fifty-four patients who were admitted to the hospital from July to December and received comprehensive treatment and sequential nursing were included in sequential nursing group (29 males and 25 females, aged 18-57 (37±11) years). The scores of pigmentation, vascularity, pliability, and thickness in Vancouver scar scale (VSS), the total score of VSS, the score of itch's impact on sleep in the four-item itch questionnaire (FIIQ), and the total score of FIIQ of patients were counted in the two groups before the first treatment (hereinafter referred to as treatment) and 3 months, 6 months, and 1 year after treatment. The treatment effective rate and the score of patients' satisfaction with the treatment effect in one year after treatment and the occurrence of adverse reaction during the treatment were counted. Data were statistically analyzed with independent sample t test, Mann-Whitney U test, and chi-square test. Results: The scores of pigmentation, vascularity, pliability, and thickness in VSS and the total VSS score of patients between the two groups before treatment were close (P>0.05). The pliability score in VSS and total VSS score after 3 months of treatment, the score of vascularity in VSS and total VSS score after 6 months of treatment, and the scores of pigmentation, vascularity, pliability, and thickness in VSS and total VSS score of patients after 1 year of treatment in sequential nursing group were significantly lower than those in conventional nursing group (with Z values of -2.51, -3.37, -2.05, -3.28, -3.12, -5.86, -4.63, -5.56, -6.76, respectively, P<0.05 or P<0.01). The score of itch's impact on sleep in FIIQ after 3 months of treatment of patients in sequential nursing group was significantly lower than that in conventional nursing group (Z=-4.17, P<0.01), and the total scores of FIIQ after 3 months, 6 months, and 1 year of treatment of patients in sequential nursing group were significantly lower than those in conventional nursing group (with Z values of -6.56, -5.53, -5.84, respectively, P<0.01). After 1 year of treatment, the treatment effective rate of patients in sequential nursing group was 96.3% (52/54), which was significantly higher than 81.8% (45/55) in conventional nursing group (χ2=5.83, P<0.05), and the score of patients' satisfaction with the treatment effect in sequential nursing group was significantly higher than that in conventional nursing group (Z=-4.49, P<0.01). During the treatment period, there was no adverse reaction in patients in sequential nursing group, but there were 3 patients with pruritus and peripheral erythema on the wound in conventional nursing group, which were improved after dressing changes. Conclusions: Sequential nursing can effectively improve the prevention and management of new skin scars in patients after deep burns on the face and neck, improve the itching, the efficiency of treatment, and the satisfaction of patients with the treatment effect.
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Affiliation(s)
- Q Q Fu
- State Key Laboratory of Trauma, Burns and Combined Injury, Institute of Burn Research, the First Affiliated Hospital of Army Medical University (the Third Military Medical University), Chongqing 400038, China
| | - M J Li
- State Key Laboratory of Trauma, Burns and Combined Injury, Institute of Burn Research, the First Affiliated Hospital of Army Medical University (the Third Military Medical University), Chongqing 400038, China
| | - L Huang
- State Key Laboratory of Trauma, Burns and Combined Injury, Institute of Burn Research, the First Affiliated Hospital of Army Medical University (the Third Military Medical University), Chongqing 400038, China
| | - J L Tan
- State Key Laboratory of Trauma, Burns and Combined Injury, Institute of Burn Research, the First Affiliated Hospital of Army Medical University (the Third Military Medical University), Chongqing 400038, China
| | - Y Q Zhou
- State Key Laboratory of Trauma, Burns and Combined Injury, Institute of Burn Research, the First Affiliated Hospital of Army Medical University (the Third Military Medical University), Chongqing 400038, China
| | - N Li
- State Key Laboratory of Trauma, Burns and Combined Injury, Institute of Burn Research, the First Affiliated Hospital of Army Medical University (the Third Military Medical University), Chongqing 400038, China
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Tan JL, Chinnaratha MA, Woodman R, Martin R, Chen HT, Carneiro G, Singh R. Diagnostic Accuracy of Artificial Intelligence (AI) to Detect Early Neoplasia in Barrett's Esophagus: A Non-comparative Systematic Review and Meta-Analysis. Front Med (Lausanne) 2022; 9:890720. [PMID: 35814747 PMCID: PMC9258946 DOI: 10.3389/fmed.2022.890720] [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] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2022] [Accepted: 05/27/2022] [Indexed: 11/18/2022] Open
Abstract
Background and Aims Artificial Intelligence (AI) is rapidly evolving in gastrointestinal (GI) endoscopy. We undertook a systematic review and meta-analysis to assess the performance of AI at detecting early Barrett's neoplasia. Methods We searched Medline, EMBASE and Cochrane Central Register of controlled trials database from inception to the 28th Jan 2022 to identify studies on the detection of early Barrett's neoplasia using AI. Study quality was assessed using Quality Assessment of Diagnostic Accuracy Studies – 2 (QUADAS-2). A random-effects model was used to calculate pooled sensitivity, specificity, and diagnostics odds ratio (DOR). Forest plots and a summary of the receiving operating characteristics (SROC) curves displayed the outcomes. Heterogeneity was determined by I2, Tau2 statistics and p-value. The funnel plots and Deek's test were used to assess publication bias. Results Twelve studies comprising of 1,361 patients (utilizing 532,328 images on which the various AI models were trained) were used. The SROC was 0.94 (95% CI: 0.92–0.96). Pooled sensitivity, specificity and diagnostic odds ratio were 90.3% (95% CI: 87.1–92.7%), 84.4% (95% CI: 80.2–87.9%) and 48.1 (95% CI: 28.4–81.5), respectively. Subgroup analysis of AI models trained only on white light endoscopy was similar with pooled sensitivity and specificity of 91.2% (95% CI: 85.7–94.7%) and 85.1% (95% CI: 81.6%−88.1%), respectively. Conclusions AI is highly accurate at detecting early Barrett's neoplasia and validated for patients with at least high-grade dysplasia and above. Further well-designed prospective randomized controlled studies of all histopathological subtypes of early Barrett's neoplasia are needed to confirm these findings further.
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Affiliation(s)
- Jin Lin Tan
- Department of Gastroenterology and Hepatology, Lyell McEwin Hospital, SA Health, Elizabeth Vale, SA, Australia
- Faculty of Health and Medical Sciences, The University of Adelaide, Adelaide, SA, Australia
| | - Mohamed Asif Chinnaratha
- Department of Gastroenterology and Hepatology, Lyell McEwin Hospital, SA Health, Elizabeth Vale, SA, Australia
- Faculty of Health and Medical Sciences, The University of Adelaide, Adelaide, SA, Australia
| | - Richard Woodman
- Flinders Centre for Epidemiology and Biostatistics, College of Medicine and Public Health, Flinders University, Bedford Park, SA, Australia
| | - Rory Martin
- Australian Institute for Machine Learning, The University of Adelaide, Adelaide, SA, Australia
| | - Hsiang-Ting Chen
- Australian Institute for Machine Learning, The University of Adelaide, Adelaide, SA, Australia
| | - Gustavo Carneiro
- Australian Institute for Machine Learning, The University of Adelaide, Adelaide, SA, Australia
| | - Rajvinder Singh
- Department of Gastroenterology and Hepatology, Lyell McEwin Hospital, SA Health, Elizabeth Vale, SA, Australia
- Faculty of Health and Medical Sciences, The University of Adelaide, Adelaide, SA, Australia
- *Correspondence: Rajvinder Singh
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Choo J, Yap J, Ismail AIDILA, Lim CL, Sumathy P, Ruan W, Sewa DW, Phua GC, Hong C, Low AHL, Lim ST, Tan JL. Intravenous epoprostenol therapy in the treatment of pulmonary arterial hypertension: the Singapore experience. Eur Heart J 2022. [DOI: 10.1093/eurheartj/ehab849.116] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Abstract
Funding Acknowledgements
Type of funding sources: None.
Background
Pulmonary arterial hypertension (PAH) is a progressive disease with significant morbidity and mortality. While intravenous (IV) Epoprostenol, a prostacyclin analogue, has been shown to improve exercise tolerance, symptoms, hemodynamics and survival, there are challenges with initiation and maintenance of this IV therapy.
Purpose
We aim to describe our local experience of the use of IV Epoprostenol in the treatment of PAH patients in Singapore, highlighting various issues and challenges.
Methods
From 2016, patients at a tertiary cardiac institution diagnosed with Group 1 PAH and remaining in intermediate to high risk class with progressive symptoms (despite being on maximum tolerable doses of PhosphoDiEsterase-5 inhibitors and Endothelin-1 receptor antagonists) were assessed and counselled for initiation of Epoprostenol therapy. With a fixed set of local protocols, comprehensive assessment and support of a multi-disciplinary team including physicians, specialist nurses and pharmacists, suitable patients were started on this treatment.
Results
A total of 12 patients (11 female, mean age 42.8 +/- 11.0 years) were included. The average New York Heart Association class of the patients initiated on Epoprostenol was II-III. The pulmonary artery pressures and pulmonary vascular resistance on right heart catheterization prior to initiation was 52.5 (IQR 47.0-54.0) mmHg and 12.6 (IQR 10.0-14.2) Woods respectively. The duration from diagnosis to time of initiating Epoprostenol was 89 (IQR 62-140) months. Epoprostenol was generally well tolerated. The most common side effect experienced was diarrhea (5/12 patients) followed by headache and musculoskeletal complains (3/12 patients each). Of the 12 patients, 6 passed away after 12 (IQR 10-16) months of Epoprostenol therapy. Of the remaining 6, PAH was diagnosed 110 (IQR 104-136) months ago and Epoprostenol therapy has been continued for 17 (IQR 14-27) months. Of those who survived, right ventricle size and PA pressures on echocardiography remained relatively stable as compared to those who passed on. 2 patients had line related infections requiring a line change 1 and 2 times respectively.
Conclusion
While not without its challenges, the establishment of concrete protocols with the support of a multidisciplinary team allows for the introduction of IV Epoprostenol as an additional potential line of effective therapy for PAH patients in Singapore.
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Affiliation(s)
- J Choo
- National Heart Centre Singapore, Singapore, Singapore
| | - J Yap
- National Heart Centre Singapore, Singapore, Singapore
| | - AIDILA Ismail
- National Heart Centre Singapore, Singapore, Singapore
| | - C L Lim
- National Heart Centre Singapore, Singapore, Singapore
| | - P Sumathy
- National Heart Centre Singapore, Singapore, Singapore
| | - W Ruan
- National Heart Centre Singapore, Singapore, Singapore
| | - D W Sewa
- Singapore General Hospital, Singapore, Singapore
| | - G C Phua
- Singapore General Hospital, Singapore, Singapore
| | - C Hong
- Singapore General Hospital, Singapore, Singapore
| | - A H L Low
- Singapore General Hospital, Singapore, Singapore
| | - S T Lim
- National Heart Centre Singapore, Singapore, Singapore
| | - J L Tan
- National Heart Centre Singapore, Singapore, Singapore
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Teoh J, Yap JLJ, Ong ZYP, Lee JDB, Wen R, Ismail AB, Sewa DW, Phua GC, Fong CHY, Low AHL, Lim ST, Tan JL. Risk stratification and prognosis in pulmonary arterial hypertension: the Singapore experience. Eur Heart J 2022. [DOI: 10.1093/eurheartj/ehab849.115] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
Abstract
Funding Acknowledgements
Type of funding sources: None.
Aims & Background: Guidelines recommend the risk stratification of patients with pulmonary arterial hypertension (PAH) at baseline and on follow-up, so as to guide the management and titration of therapy in these patients. This approach has been validated in various pulmonary hypertension registries in the West. We aim to study the value of risk stratification on the prognosis of PAH patients in Asia.
Methods
A retrospective review of all PAH patients from 2002 to 2018 from a single tertiary cardiac centre was performed. Inclusion criteria was the availability of both initial visit and follow-up data. Patients were classified into low-, medium-, and high-risk groups in both initial and follow-up visits based on the variables in the 2015 ESC/ERS PH risk stratification table according to the "score and average" method used by SPAHR and COMPERA registries (total score divided by number of variables assessed and rounded to nearest integer). An average score of 1, 2 and 3 was defined as low, medium and high risk respectively. The primary outcomes was all-cause mortality.
Results
A total of 102 patients (mean age 57 ± 18 years old, 82 females) were included. Survival was significantly affected by PAH subtype and risk profile. On multivariate analysis, baseline risk did not impact on mortality. Follow-up risk stage impacted on prognosis, with significantly poorer prognosis noted in both intermediate- (adj HR 3.12, 95% CI 1.03 – 9.48, p = 0.045) and high-risk (adj HR = 7.84, 95% CI 2.22 – 27.64, p = 0.001) groups. Patients who improved their risk groups to low risk on follow-up had similar survival to stable low-risk patients, but those patients whose risk group worsened on follow-up had significantly worse prognosis (adj HR = 5.44, 95% CI 1.26 – 13.75, p = 0.02).
Conclusion
Risk stratification is useful in prognosticating Asian PAH patients. There is potential survival benefit in optimising treatment to achieve a low-risk profile.
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Affiliation(s)
- J Teoh
- Singapore General Hospital, Singapore, Singapore
| | - J L J Yap
- National Heart Centre Singapore, Singapore, Singapore
| | - Z Y P Ong
- National Heart Centre Singapore, Singapore, Singapore
| | - J D B Lee
- National Heart Centre Singapore, Singapore, Singapore
| | - R Wen
- National Heart Centre Singapore, Singapore, Singapore
| | - A B Ismail
- National Heart Centre Singapore, Singapore, Singapore
| | - D W Sewa
- Singapore General Hospital, Singapore, Singapore
| | - G C Phua
- Singapore General Hospital, Singapore, Singapore
| | - C H Y Fong
- Singapore General Hospital, Singapore, Singapore
| | - A H L Low
- Singapore General Hospital, Singapore, Singapore
| | - S T Lim
- National Heart Centre Singapore, Singapore, Singapore
| | - J L Tan
- Singapore General Hospital, Singapore, Singapore
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Li HS, Yuan ZQ, Song HP, Luo QZ, Xiang F, Ma SY, Zhou JY, Tan JL, Zhou L, Peng YZ, Luo GX. [Clinical application of extracorporeal membrane oxygenation in the treatment of burn patients with acute respiratory distress syndrome: a retrospective analysis and systematic review]. Zhonghua Shao Shang Za Zhi 2021; 37:911-920. [PMID: 34689460 DOI: 10.3760/cma.j.cn501120-20210803-00266] [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] [Grants] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
Objective: To analyze the clinical effect of extracorporeal membrane oxygenation (ECMO) in the treatment of burn patients with acute respiratory distress syndrome (ARDS). Methods: The retrospective observational study and the systematic review were applied. From March 2014 to July 2020, five burn patients with ARDS received ECMO treatment in the First Affiliated Hospital of Army Medical University (the Third Military Medical University). All the five patients were male, aged from 40 to 62 years. The average total burn surface area was 58.8% total body surface area (TBSA) and four cases had severe inhalation injury. Patient's ECMO starting time, duration and mode, and whether successfully weaned or the cause of death, and others. were recorded. Furthermore, the changes of oxygenation and infection before, during, and after utilizing ECMO were analyzed. PubMed and Web of Science from the establishment of each database to August 2021 were searched using "Extracorporeal Membrane Oxygenation", "ECMO", "burn", "inhalation" as the search terms and "Title/Abstract" as the field to retrieve the clinical articles that meet the selection criteria . Basic information were extracted from the articles, including sample size, gender, age, total burn area, inhalation injury, the indication of ECMO, the start and lasting time of ECMO, ECMO mode, rate of successful weaning, complications of ECMO, mortality, the combined application of continuous renal replacement therapy (CRRT). Results: Five patients started venovenous ECMO on an average of 10.2 days after injury and lasted an average of 180.4 hours. Three out of 5 patients were weaned successfully with one patient survived. Four patients died of multiple organ dysfunction syndrome (MODS) and septic shock. Compared with those before ECMO treatment, the arterial oxygen partial pressure (PaO2) and oxygen saturation in arterial blood (SaO2) of three successfully weaned patients obviously increased during and after ECMO treatment. The fraction of inspired oxygen (FiO2) decreased below 50% and PaO2/FiO2 ratio increased above 200 mmHg (1 mmHg=0.133 kPa) during and after ECMO. Furthermore, lactic acid and respiratory rate decreased, basically. Compared with those before ECMO, PaO2 and SaO2 in the other two patients during ECMO, who failed to be weaned, continuously decreased while lactic acid increased. Before and during ECMO, the PaO2/FiO2 ratios of unsuccessfullg weaned cases were less than 200 mmHg, and partial pressure of carbon dioxide in arterial blood (PaCO2) were more than 40 mmHg. Compared with those before ECMO, there were no significant changes in body temperature during and after ECMO, which were less than 38 ℃. Compared with those before ECMO, the leucocyte number (the index without this in unsuccessfully weaned cases was omitted, the same as below) in four patients showed a significant decrease during ECMO, but rose after removal of ECMO. The proportion of neutrophils in three patients were slightly higher during ECMO than before ECMO, and did not change significantly after removal of ECMO. Compared with those before ECMO, platelet counts in three patients were significantly reduced during ECMO, and all five patients during ECMO were below normal levels. Compared with those before ECMO, the procalcitonin levels in four deaths were significantly increased during ECMO. Catheter culture of microorganism was performed in three successfully weaned patients, all of which were negative. A total of 13 literature were included, ranging from 1990 to 2019. The sample size in 6 studies was less than 10, and the sample size in 4 studies was between 10 and 20, and only 2 literatures had a sample size larger than 50. ECMO was applied in 295 burn patients with overall mortality of 48.8% (144/295), including 157 adults and 138 children. The most common indication of ECMO was severe ARDS. Among 157 adult burn patients (95 males and 65 females), 36 cases had inhalation injury. The average burn area was 27%-37%TBSA in 5 reported studies and was more than 50%TBSA in 2 reported studies. The most common mode was venovenous ECMO. ECMO treatment began 26.5 hours to 7.4 days after injury and lasted from 90 hours to 18 days, and the rate of successful weaning ranged from 50% to 100%. The most common complications were bleeding and infection. The mortality was 52.9% (83/157). MODS and sepsis were the leading causes of death. Among 138 pediatric burn patients (77 boys and 61 girls), 29 patients had inhalation injury. The average burn area was 17%-50.2%TBSA in 3 studies. ECMO treatment lasted from 165.2 hours to 324.4 hours. Bleeding was the most common complication. The mortality was 44.2% (61/138). Conclusions: ECMO is an effective strategy for the salvage treatment of burns complicated with ARDS. Furthermore, the prevention and treatment of bleeding, infection and organ dysfunction should be emphasized during the use of ECMO. More importantly, evidence-based guidelines for burns are urgently needed to further improve the clinical effect of ECMO.
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Affiliation(s)
- H S Li
- State Key Laboratory of Trauma, Burns and Combined Injury, Institute of Burn Research, the First Affiliated Hospital of Army Medical University (the Third Military Medical University), Chongqing Key Laboratory for Disease Proteomics, Chongqing 400038, China
| | - Z Q Yuan
- State Key Laboratory of Trauma, Burns and Combined Injury, Institute of Burn Research, the First Affiliated Hospital of Army Medical University (the Third Military Medical University), Chongqing Key Laboratory for Disease Proteomics, Chongqing 400038, China
| | - H P Song
- State Key Laboratory of Trauma, Burns and Combined Injury, Institute of Burn Research, the First Affiliated Hospital of Army Medical University (the Third Military Medical University), Chongqing Key Laboratory for Disease Proteomics, Chongqing 400038, China
| | - Q Z Luo
- State Key Laboratory of Trauma, Burns and Combined Injury, Institute of Burn Research, the First Affiliated Hospital of Army Medical University (the Third Military Medical University), Chongqing Key Laboratory for Disease Proteomics, Chongqing 400038, China
| | - F Xiang
- State Key Laboratory of Trauma, Burns and Combined Injury, Institute of Burn Research, the First Affiliated Hospital of Army Medical University (the Third Military Medical University), Chongqing Key Laboratory for Disease Proteomics, Chongqing 400038, China
| | - S Y Ma
- State Key Laboratory of Trauma, Burns and Combined Injury, Institute of Burn Research, the First Affiliated Hospital of Army Medical University (the Third Military Medical University), Chongqing Key Laboratory for Disease Proteomics, Chongqing 400038, China
| | - J Y Zhou
- State Key Laboratory of Trauma, Burns and Combined Injury, Institute of Burn Research, the First Affiliated Hospital of Army Medical University (the Third Military Medical University), Chongqing Key Laboratory for Disease Proteomics, Chongqing 400038, China
| | - J L Tan
- State Key Laboratory of Trauma, Burns and Combined Injury, Institute of Burn Research, the First Affiliated Hospital of Army Medical University (the Third Military Medical University), Chongqing Key Laboratory for Disease Proteomics, Chongqing 400038, China
| | - L Zhou
- State Key Laboratory of Trauma, Burns and Combined Injury, Institute of Burn Research, the First Affiliated Hospital of Army Medical University (the Third Military Medical University), Chongqing Key Laboratory for Disease Proteomics, Chongqing 400038, China
| | - Y Z Peng
- State Key Laboratory of Trauma, Burns and Combined Injury, Institute of Burn Research, the First Affiliated Hospital of Army Medical University (the Third Military Medical University), Chongqing Key Laboratory for Disease Proteomics, Chongqing 400038, China
| | - G X Luo
- State Key Laboratory of Trauma, Burns and Combined Injury, Institute of Burn Research, the First Affiliated Hospital of Army Medical University (the Third Military Medical University), Chongqing Key Laboratory for Disease Proteomics, Chongqing 400038, China
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Tan BEX, Tan JL, Abu Sheika M, Thakkar S, von Doenhoff L. A ticking time bomb: thrombus straddling a patent foramen ovale. QJM 2020; 113:483-484. [PMID: 31995203 DOI: 10.1093/qjmed/hcaa016] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/11/2020] [Indexed: 11/14/2022] Open
Affiliation(s)
- B E-X Tan
- Department of Internal Medicine, Rochester General Hospital, 1425 Portland Avenue, Rochester, NY 14621, USA
| | - J L Tan
- Department of Internal Medicine, Crozer-Chester Medical Center, 1 Medical Center Blvd, Upland, PA 19013, USA
| | - M Abu Sheika
- Department of Internal Medicine, Rochester General Hospital, 1425 Portland Avenue, Rochester, NY 14621, USA
| | - S Thakkar
- Department of Internal Medicine, Rochester General Hospital, 1425 Portland Avenue, Rochester, NY 14621, USA
| | - L von Doenhoff
- Department of Internal Medicine, Division of Cardiology, Rochester General Hospital, 1425 Portland Avenue, Rochester, NY 14621, USA
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Ma SY, Yuan ZQ, Peng YZ, Luo QZ, Song HP, Xiang F, Tan JL, Zhou JY, Li N, Hu GZ, Luo GX. [Recommendations for normalizing the medical practices of burn treatment during the outbreak of coronavirus disease 2019]. Zhonghua Shao Shang Za Zhi 2020; 36:465-469. [PMID: 32111114 DOI: 10.3760/cma.j.cn501120-20200224-00083] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
2019 novel coronavirus (2019-nCoV) is one of the beta coronaviruses and is identified as the pathogen of the severe " coronavirus disease 2019 (COVID-19)" in 2019. China manages COVID-19 according to the reguirement of the highest level infectious diseases in China. Currently, the prevention and control of COVID-19 in China is at a critical period. Burn Department as an emergency discipline is confronted with risk of 2019-nCoV infection. Based on the guidelines for the diagnosis and treatment of COVID-19 (6th trial edition), in combination with the latest literature at home and abroad, the features of the COVID-19, the recommendations for the COVID-19 prevention and control issued by the National Health Commission of China, and the management experience of COVID-19 diagnosis and treatment of other related disciplines, we put forward some recommendations for the medical practices of burn treatment during the outbreak of the COVID-19 in outpatient and emergency, inpatient treatment, and the management of operation theatres and wards, etc. We hope these recommendations could benefit the medical professionals in the field of burn treatment and relevant hospital management during the outbreak of COVID-19, improve burn treatment, and avoid or reduce the risk of infection of medical staff.
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Affiliation(s)
- S Y Ma
- State Key Laboratory of Trauma, Burns and Combined Injury, Institute of Burn Research, the First Affiliated Hospital of Army Medical University (the Third Military Medical University), Chongqing 400038, China
| | - Z Q Yuan
- State Key Laboratory of Trauma, Burns and Combined Injury, Institute of Burn Research, the First Affiliated Hospital of Army Medical University (the Third Military Medical University), Chongqing 400038, China
| | - Y Z Peng
- State Key Laboratory of Trauma, Burns and Combined Injury, Institute of Burn Research, the First Affiliated Hospital of Army Medical University (the Third Military Medical University), Chongqing 400038, China
| | - Q Z Luo
- State Key Laboratory of Trauma, Burns and Combined Injury, Institute of Burn Research, the First Affiliated Hospital of Army Medical University (the Third Military Medical University), Chongqing 400038, China
| | - H P Song
- State Key Laboratory of Trauma, Burns and Combined Injury, Institute of Burn Research, the First Affiliated Hospital of Army Medical University (the Third Military Medical University), Chongqing 400038, China
| | - F Xiang
- State Key Laboratory of Trauma, Burns and Combined Injury, Institute of Burn Research, the First Affiliated Hospital of Army Medical University (the Third Military Medical University), Chongqing 400038, China
| | - J L Tan
- State Key Laboratory of Trauma, Burns and Combined Injury, Institute of Burn Research, the First Affiliated Hospital of Army Medical University (the Third Military Medical University), Chongqing 400038, China
| | - J Y Zhou
- State Key Laboratory of Trauma, Burns and Combined Injury, Institute of Burn Research, the First Affiliated Hospital of Army Medical University (the Third Military Medical University), Chongqing 400038, China
| | - N Li
- State Key Laboratory of Trauma, Burns and Combined Injury, Institute of Burn Research, the First Affiliated Hospital of Army Medical University (the Third Military Medical University), Chongqing 400038, China
| | - G Z Hu
- State Key Laboratory of Trauma, Burns and Combined Injury, Institute of Burn Research, the First Affiliated Hospital of Army Medical University (the Third Military Medical University), Chongqing 400038, China
| | - G X Luo
- State Key Laboratory of Trauma, Burns and Combined Injury, Institute of Burn Research, the First Affiliated Hospital of Army Medical University (the Third Military Medical University), Chongqing 400038, China
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13
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Tan JL, Mugwagwa AN, Cieslik L, Joshi R. Nivolumab-induced myocarditis complicated by complete atrioventricular block in a patient with metastatic non-small cell lung cancer. BMJ Case Rep 2019; 12:12/7/e229963. [PMID: 31300602 DOI: 10.1136/bcr-2019-229963] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [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: 01/05/2023] Open
Abstract
We report a case of a 74-year-old man who developed myocarditis complicated by atrioventricular (AV) block following two doses of nivolumab for the treatment of non-small cell lung cancer. A diagnosis of drug-induced acute myocarditis with complete AV block was considered on the basis of elevated troponin, new onset left ventricular (LV) systolic dysfunction, absence of acute myocardial infarction and some findings suggestive of myocarditis on cardiac magnetic resonance. The patient was commenced on glucocorticoids, perindopril and carvedilol. AV block and LV dysfunction persisted despite 2 weeks of treatment. He ultimately became hypotensive which prompted an implantation of a cardiac resynchronisation therapy pacemaker. Follow-up echocardiogram at 6 weeks showed resolution of LV systolic dysfunction. However, he continued to have AV block.
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Affiliation(s)
- Jin Lin Tan
- Division of Medicine, Lyell McEwin Hospital, Elizabeth Vale, South Australia, Australia
| | - Augustine Nyasha Mugwagwa
- Division of Medicine, Lyell McEwin Hospital, Elizabeth Vale, South Australia, Australia.,University of Adelaide School of Medicine, Adelaide, South Australia, Australia
| | - Luke Cieslik
- Division of Medicine, Lyell McEwin Hospital, Elizabeth Vale, South Australia, Australia
| | - Rohit Joshi
- University of Adelaide School of Medicine, Adelaide, South Australia, Australia.,Department of Oncology, Lyell McEwin Hospital, Elizabeth Vale, South Australia, Australia
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Lee PT, Uy FMR, Le TT, Foo JS, Tan JL, Chin CWL. P367TGA with interarterial coronary artery course and Athlete"s heart. Eur Heart J Cardiovasc Imaging 2019. [DOI: 10.1093/ehjci/jez109.008] [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] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Affiliation(s)
- P T Lee
- National Heart Centre Singapore, Singapore, Singapore
| | - F M R Uy
- National Heart Centre Singapore, Singapore, Singapore
| | - T T Le
- National Heart Centre Singapore, Singapore, Singapore
| | - J S Foo
- National Heart Centre Singapore, Singapore, Singapore
| | - J L Tan
- National Heart Centre Singapore, Singapore, Singapore
| | - C W L Chin
- National Heart Centre Singapore, Singapore, Singapore
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15
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Tan JL, Saks M, DelCollo JM, Paryavi M, Visvanathan S, Geller C. Accidental hypothermia cardiac arrest treated successfully with invasive body cavity lavage. QJM 2018; 111:563-564. [PMID: 29660066 DOI: 10.1093/qjmed/hcy075] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/26/2018] [Revised: 03/30/2018] [Indexed: 11/12/2022] Open
Affiliation(s)
- J L Tan
- Department of Internal Medicine, Crozer-Chester Medical Center, 1 Medical Center Boulevard, Upland, PA, USA
| | - M Saks
- Department of Emergency Medicine, Crozer-Chester Medical Center, 1 Medical Center Boulevard, Upland, PA, USA
| | - J M DelCollo
- Department of Emergency Medicine, Crozer-Chester Medical Center, 1 Medical Center Boulevard, Upland, PA, USA
| | - M Paryavi
- Department of Emergency Medicine, Crozer-Chester Medical Center, 1 Medical Center Boulevard, Upland, PA, USA
| | - S Visvanathan
- Department of Internal Medicine, Crozer-Chester Medical Center, 1 Medical Center Boulevard, Upland, PA, USA
| | - C Geller
- Department of Cardiothoracic Surgery, Crozer-Chester Medical Center, 1 Medical Center Boulevard, Upland, PA, USA
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16
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Liu JY, Tan WK, Tan EL, Tan JL, Tan LK. A case of successfully managed pregnancy in a patient with complex cyanotic congenital heart disease. Obstet Med 2017; 10:88-92. [PMID: 28680470 PMCID: PMC5480644 DOI: 10.1177/1753495x16678487] [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] [Received: 05/24/2016] [Accepted: 10/17/2016] [Indexed: 03/27/2024] Open
Abstract
Medical advances have increased survival of patients with congenital heart disease. However, cardiac disease in pregnancy carries significant maternal and fetal risks, posing enormous challenges to obstetricians. Cyanotic congenital heart disease is associated with maternal complications such as arrhythmias, thromboembolic events and death. Fetal complications include small for gestational age, miscarriage and prematurity. Cyanotic congenital heart disease patients who continue their pregnancies require holistic multidisciplinary team care with early and coordinated planning for delivery. Management of such patients include early counseling regarding pregnancy-associated risks, close monitoring of their cardiac function and regular scanning for fetal assessment. Choice of anesthesia for these patients requires meticulous planning to achieve a favorable balance between systemic and pulmonary vascular resistance, ensuring minimal change in right-to-left shunting. We report a case of a successfully managed pregnancy in a patient with complex congenital heart disease and a single ventricle of left ventricle morphology.
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Affiliation(s)
- JY Liu
- Singapore General Hospital, Singapore, Singapore
| | - WK Tan
- Singapore General Hospital, Singapore, Singapore
| | - EL Tan
- Singapore General Hospital, Singapore, Singapore
| | - JL Tan
- Singapore General Hospital, Singapore, Singapore
| | - LK Tan
- Singapore General Hospital, Singapore, Singapore
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Abstract
PURPOSE To evaluate outcomes of arthroscopic subacromial decompression for stage-II impingement. METHODS Records of 42 consecutive patients with stage-II impingement treated by arthroscopic subacromial decompression from January 2000 to February 2002 were reviewed. Clinical outcomes were measured using the UCLA shoulder rating scale, and radiological outcomes using anteroposterior and supraspinatus outlet shoulder radiographs. RESULTS The mean follow-up period was 14.6 (range, 12-30) months. Using the UCLA scale, 14 (33%) patients had an excellent result, 21 (50%) had a good result, 4 (10%) had a fair result, and 3 (7%) had a poor result. Mean component scores for the UCLA scale were: 8.0 for pain, 8.8 for function, 4.5 for forward flexion, and 4.5 for strength. The mean extent of resection was 2.9 mm in the anteroposterior and 2.0 mm in the supraspinatus outlet radiographs. There was no correlation between the extent of acromial resection and the UCLA shoulder rating scores. CONCLUSION Short-term results of arthroscopic subacromial decompression for stage-II impingement are favourable.
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Affiliation(s)
- K K Lim
- Department of Orthopaedic Surgery, Changi General Hospital, Singapore
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18
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Yang K, Tan JL, Wu TX. Alkylating agents for Waldenstrom's macroglobulinemia. Hippokratia 2007. [DOI: 10.1002/14651858.cd006719] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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Tsou IYY, Yegappan M, Ong WS, Goh POL, Tan JL, Chee TSG. Cartilage injury and repair: assessment with magnetic resonance imaging. Singapore Med J 2006; 47:80-7; quiz 88. [PMID: 16397729] [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: 05/06/2023]
Abstract
Articular cartilage damage plays a major role in joint degeneration and dysfunction. Accurate assessment of the morphology and degree of cartilage wear is important in diagnosis, prognosis and management, particularly as many of these patients are young or participate in high-performance sports. Magnetic resonance imaging is able to directly evaluate such injuries, due to its high spatial resolution and excellent soft-tissue contrast resolution. This pictoral essay aims to demonstrate normal and damaged articular cartilage on MR imaging, as well as surgically-repaired cartilage.
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Affiliation(s)
- I Y Y Tsou
- Department of Diagnostic Radiology, Tan Tock Seng Hospital, 11 Jalan Tan Tock Seng, Singapore 308433.
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Tan JL, Davlouros PA, McCarthy KP, Gatzoulis MA, Ho SY. Intrinsic histological abnormalities of aortic root and ascending aorta in tetralogy of Fallot: evidence of causative mechanism for aortic dilatation and aortopathy. Circulation 2005; 112:961-8. [PMID: 16087793 DOI: 10.1161/circulationaha.105.537928] [Citation(s) in RCA: 127] [Impact Index Per Article: 6.7] [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: 11/16/2022]
Abstract
BACKGROUND Dilatation of the aortic root is a known feature in tetralogy of Fallot (TOF) patients with pulmonary stenosis (PS) or pulmonary atresia (PA). We hypothesized that intrinsic histological abnormalities of the aortic wall present since infancy are an important causative factor leading to aortic root dilatation. METHODS AND RESULTS We examined the aortic histology of 17 cases with TOF and PS/PA from our cardiac morphology archive and compared them with a control group of normal aortas. Measured circumference of the aortic root at the sinotubular junction and at the ascending aorta was indexed to the left ventricle. Aortic walls were studied by light microscopy with the use of various stains. Seventeen TOF cases (7 with PS, 10 with PA) including 7 infants, 2 children, and 8 adults were compared with 11 hearts with normal aorta. Aortic root circumference to left ventricular index and ascending aortic circumference to left ventricular index were 1.24+/-0.25 and 1.37+/-0.24, respectively, in the TOF group versus 0.89+/-0.10 and 0.88+/-0.11, respectively, in the control group (P<0.001). Histological changes of grade 2 or 3 were present in 29% (medionecrosis), 82% (fibrosis), 35% (cystic medial necrosis), and 59% (elastic fragmentation) in the ascending aorta of the TOF group. Histology grading scores were significantly higher in the TOF group (median score, 7; range, 1 to 12) compared with normal controls (median score, 2; range, 0 to 6) and correlated with the ascending aortic circumference to left ventricular index (r=0.525, P=0.03). CONCLUSIONS There are marked histological abnormalities in the aortic root and ascending aortic wall of patients with TOF present from infancy, suggesting a causative mechanism for subsequent aortic root dilatation.
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Affiliation(s)
- J L Tan
- Adult Congenital Heart Disease Unit, Royal Brompton Hospital, National Heart and Lung Institute, Imperial College, London, UK
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Chong RWW, Tan JL. Rising trend of anterior cruciate ligament injuries in females in a regional hospital. Ann Acad Med Singap 2004; 33:298-301. [PMID: 15175767] [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: 04/29/2023]
Abstract
INTRODUCTION We see a rising trend in the number of anterior cruciate ligament (ACL) injuries in females over the past 4 years (1999 to 2002). This article seeks to identify and examine the rising trend in the number of ACL injuries in females in our institution over this period. MATERIALS AND METHODS Two hundred and fifty-nine patients with ACL reconstructions were identified and their casenotes were retrieved from the medical records office. Of these, 13 were females. RESULTS The number of ACL reconstructions has increased from 9 cases to 144 cases a year from 1999 to 2002. Over this period, 13 female cases (3 in 2001 and 10 in 2002) with an age range of 13 to 38 years were performed in our institution. Their injuries were mainly sustained from a bad landing or during pivoting on 1 leg. There were 8 patients (61.5 %) with prior conditioning and experience and 5 without (38.5 %). The mean number of years of prior training was 4.4 years. Of these 8, 4 were netball players. All were competitive players either at the school or club level and they were all playing as goal attackers. CONCLUSION Linear regression analysis shows a significant increase in the number of ACL reconstructions performed for females in our institution over this time period. Netball was a common sport in our series. This suggests a likely relationship between netball and ACL injuries. All the patients were playing as goal attackers. The area of court covered and frequency of jump-stop and sudden deceleration activities could be a cause.
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Affiliation(s)
- R W W Chong
- Medical Officer, Department of Orthopaedic Surgery, Changi General Hospital, Singapore
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Fong SY, Tan JL. Septic arthritis after arthroscopic anterior cruciate ligament reconstruction. Ann Acad Med Singap 2004; 33:228-34. [PMID: 15098639] [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: 04/29/2023]
Abstract
INTRODUCTION A retrospective review of postoperative infected anterior cruciate ligament (ACL) reconstruction was done on 472 consecutive cases in one institution. The purpose was to assess the incidence, diagnosis, treatment and outcome factors. MATERIALS AND METHODS Out of 472 arthroscopic-assisted ACL reconstructions performed between 1999 and 2002, 7 (1%) postoperative deep intra-articular infections were detected. Seven males with a mean age of 23 years (range, 19 to 30 years) formed the study group; 3 had undergone prior knee surgery. RESULTS Four patients had acute infection (<2 weeks), 3 had subacute infection (2 weeks to 2 months) and none had late infection (>2 months). All were admitted within 24 hours of onset of symptoms and underwent immediate arthroscopic lavage, incision and drainage of abscess, debridement with graft retention and intravenous (8 to 31 days) followed by oral (4 to 6 weeks) antibiotics. Staphylococcus aureus was present in 4 patients, Peptostreptococcus in 3, Klebsiella in 1, and Enterobacter in 1. The patients underwent an average of 1.4 arthroscopic procedures (range, 1 to 3 procedures), with an average hospital stay of 17.3 days per patient. All were evaluated at an average of 11.7 months (range, 5 to 26 months). In all cases, the infection resolved with stable knees and with all grafts and implants retained. Although rare, early diagnosis and prompt treatment of infection can result in successful eradication without sacrificing the graft.
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Affiliation(s)
- S Y Fong
- Department of Orthopaedic Surgery, Tan Tock Seng Hospital, Singapore.
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Tan JL, Hsu LF, Kam RML, Teo WS. Immediate and mid-term safety and efficacy of single lead VDD pacemakers for patients with atrioventricular block and normal sinus node function--a single centre experience. Ann Acad Med Singap 2003; 32:101-5. [PMID: 12625106] [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: 03/01/2023]
Abstract
INTRODUCTION Single lead atrial synchronous ventricular pacing (VDD) is increasingly being used in place of conventional dual chamber pacing (DDD) for patients with atrioventricular block and preserved sinus node function. Compared to the latter, VDD pacemakers provide similar haemodynamic benefits derived from atrial synchronous pacing, with the added benefit of an easier implant procedure. OBJECTIVE To review the use, safety and efficacy of VDD pacing in a single tertiary referral centre. MATERIALS AND METHODS A review of all patients with atrioventricular block and normal sinus node function implanted with a VDD pacemaker over a 2-year period at a local tertiary cardiac referral centre. Data on complications, atrial sensing performance and maintenance of atrioventricular synchrony during implant and at subsequent follow-up visits were obtained from a prospectively maintained registry and analysed. RESULTS Forty-one patients (17 males, 24 females) with a mean age of 72 +/- 9 years received VDD pacing for various forms of high-grade atrioventricular block. The average implantation time was 46.8 +/- 17.1 minutes, and a pneumothorax in 1 patient was the only complication. Electrical measurements at implantation and subsequent follow-up visits revealed an initial rapid decrease in atrial signal amplitude (mean atrial P wave at implant 3.1 +/- 1.1 mV, predischarge 1.9 +/- 1.3 mV) which began to stabilise after 3 months, reaching a mean atrial P wave value of 1.3 +/- 0.3 mV at 24 months. The atrial sensing performance (percentage of atrial synchronous ventricular complexes) was 97% over a mean follow-up period of 9.9 months. Four patients (10%) developed paroxysmal atrial tachyarrhythmias. Sinus node dysfunction was not observed in any of our patients during the follow-up period. CONCLUSION In patients with atrioventricular block and preserved sinus node function, single lead VDD pacing is safe and effective in maintaining a physiological atrial synchronous pacing mode.
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Affiliation(s)
- J L Tan
- Department of Cardiology, National Heart Centre, Mistri Wing, 17 Third Hospital Avenue, Singapore 168752
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Brown GA, Tan JL, Kirkley A. The lax shoulder in females. Issues, answers, but many more questions. Clin Orthop Relat Res 2000:110-22. [PMID: 10738420] [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] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
A review of the existing data on shoulder laxity in females reveals there are insufficient data to confirm the commonly held belief that shoulders in females are more lax than shoulders in males. Laxity is not synonymous with instability. Although females may have increased generalized joint laxity relative to males, generalized joint laxity does not correlate with shoulder laxity. There is conflicting data regarding shoulder laxity and gender. A review of patients with multidirectional instability who were treated operatively showed that 55% of the patients were female (N = 94) and 45% were male (N = 77), but the number or gender of patients who were treated nonoperatively was not reported. Multidirectional instability is reviewed in the context of the lax shoulder in the female. Initial treatment should be nonoperative, emphasizing physical therapy and dynamic stabilization of the shoulder. If nonoperative treatment fails, open or arthroscopic inferior capsular shift stabilization is recommended. Additional basic science and clinical trials are needed to determine whether thermal capsulorrhaphy should be considered in the treatment of patients with multidirectional instability of the shoulder.
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Tan JL, Chang PC, Mitra AK, Tay BK. Anthropometry of anterior cruciate ligament in Singaporean Chinese. Ann Acad Med Singap 1998; 27:776-9. [PMID: 10101548] [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: 02/11/2023]
Abstract
Accurate reproduction of the anatomy of the anterior cruciate ligament during reconstructive surgery is paramount for obtaining good functional results. Graft size and length are important components of the reconstruction and the references we have used are Western figures. We feel that these Western figures do not apply to our local population. We performed an anthropometric study to test the hypothesis that the anterior cruciate ligament in the Singaporean Chinese is smaller than that quoted in Western literature. The study revealed that the anterior cruciate ligament in Singaporean Chinese is shorter and narrower. More importantly, the anterior cruciate ligament orientation in our study population is more vertical. This suggests that placement of the femoral tunnel in anterior cruciate ligament reconstruction has to be in a more vertical position to reproduce the physiometry of the anterior cruciate ligament.
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Affiliation(s)
- J L Tan
- Department of Orthopaedic Surgery, Singapore General Hospital, Singapore
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Silveira LA, Smith JL, Tan JL, Spudich JA. MLCK-A, an unconventional myosin light chain kinase from Dictyostelium, is activated by a cGMP-dependent pathway. Proc Natl Acad Sci U S A 1998; 95:13000-5. [PMID: 9789030 PMCID: PMC23685 DOI: 10.1073/pnas.95.22.13000] [Citation(s) in RCA: 20] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Dictyostelium myosin II is activated by phosphorylation of its regulatory light chain by myosin light chain kinase A (MLCK-A), an unconventional MLCK that is not regulated by Ca2+/calmodulin. MLCK-A is activated by autophosphorylation of threonine-289 outside of the catalytic domain and by phosphorylation of threonine-166 in the activation loop by an unidentified kinase, but the signals controlling these phosphorylations are unknown. Treatment of cells with Con A results in quantitative phosphorylation of the regulatory light chain by MLCK-A, providing an opportunity to study MLCK-A's activation mechanism. MLCK-A does not alter its cellular location upon treatment of cells with Con A, nor does it localize to the myosin-rich caps that form after treatment. However, MLCK-A activity rapidly increases 2- to 13-fold when Dictyostelium cells are exposed to Con A. This activation can occur in the absence of MLCK-A autophosphorylation. cGMP is a promising candidate for an intracellular messenger mediating Con A-triggered MLCK-A activation, as addition of cGMP to fresh Dictyostelium lysates increases MLCK-A activity 3- to 12-fold. The specific activity of MLCK-A in cGMP-treated lysates is 210-fold higher than that of recombinant MLCK-A, which is fully autophosphorylated, but lacks threonine-166 phosphorylation. Purified MLCK-A is not directly activated by cGMP, indicating that additional cellular factors, perhaps a kinase that phosphorylates threonine-166, are involved.
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Affiliation(s)
- L A Silveira
- Department of Biochemistry, Beckman Center, Stanford University Medical School, Stanford, CA 94305-5307, USA
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Tan JL, Marshall SD, Kallal RH, Monahan R, Jacobson RS. The relationship between presurgical hyoid bone position and 1-year postsurgical change in mandibular position following mandibular advancement surgery. Int J Adult Orthodon Orthognath Surg 1995; 10:263-8. [PMID: 9082015] [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: 02/04/2023]
Abstract
The presurgical hyoid bone position and its relationship to changes in the position of the mandible 1 year following mandibular advancement surgery was studied. Thirty-eight adult patients with mandibular deficiency underwent surgical correction with a bilateral sagittal split ramus osteotomy procedure and rigid fixation. Lateral cephalometric radiographs taken presurgically, 1 week postsurgically, and approximately 1 year postsurgically were hand traced and digitized. Horizontal and vertical measurements, made from the landmarks hyoidale and pogonion to a vertical reference line perpendicular to sellanasion line + 7 degrees and passing through basion point, were used to determine the position of the hyoid bone and the mandible, respectively. The presurgical hyoid bone position and the amount of postsurgical change in position of the mandible were compared using the Pearson's correlation coefficient (r). Results of this study indicate that no statistically significant correlation exists between the presurgical hyoid bone position and the degree of mandibular change 1 year following mandibular advancement surgery (P < .05).
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Affiliation(s)
- J L Tan
- Division of Clinical Orthodontics, Northwestern University School of Dentistry, Chicago, Illinois, USA
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Tan JL, Sgro MA. Dens evaginatus: three clinical presentations of dens evaginatus in children. ASDC J Dent Child 1994; 61:330-3. [PMID: 7897000] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Affiliation(s)
- J L Tan
- Department of Dentistry, Montreal Children's Hospital, Quebec, Canada
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Tan JL, Lo NN, Tan SK. Surgical treatment of metastatic long bone disease. Singapore Med J 1992; 33:355-8. [PMID: 1411663] [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: 12/26/2022]
Abstract
A retrospective study of the results of operative treatment of 60 long bones secondaries in 46 patients was carried out. The mean period of follow-up was 10 months. The most common primary in this study was carcinoma of the breast (28.2%), followed by carcinoma of the lung (21.7%) and unknown primary (10.9%). Three groups of patients were studied--pathological fracture group, prophylactic fixation group and a mixed group. In the pathological fracture group, 70% of patients achieved good to excellent pain relief and 60.9% was able to walk with or without walking aids. In the prophylactic group, all the patients achieved good to excellent pain relief and 60% were able to ambulate with or without walking aids. In the mixed group, all the patients achieved good to excellent pain relief and 66.6% of the patients were able to walk with aids. The operative mortality in both the pathological fracture group and prophylactic fixation group was 10% and 33.3% in the mixed group. Multiple internal fixation performed at one operative session was associated with high operative mortality (50%).
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Affiliation(s)
- J L Tan
- Department of Orthopaedic Surgery O, Singapore General Hospital
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Affiliation(s)
- J L Tan
- Department of Cell Biology, Stanford University School of Medicine, California 94305
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Tan JL, Spudich JA. Characterization and bacterial expression of the Dictyostelium myosin light chain kinase cDNA. Identification of an autoinhibitory domain. J Biol Chem 1991; 266:16044-9. [PMID: 1651931] [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] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022] Open
Abstract
A full-length cDNA corresponding to the Dictyostelium myosin light chain kinase gene has been isolated and characterized. Sequence analysis of the cDNA confirms conserved protein kinase subdomains and reveals that the Dictyostelium sequence is highly homologous to those of calcium/calmodulin-dependent protein kinases, including myosin light chain kinases from higher eukaryotes. Despite the high homologies to calcium/calmodulin-dependent protein kinases, there is no recognizable calmodulin-binding domain within the Dictyostelium sequence. However, the Dictyostelium myosin light chain kinase possesses a putative auto-inhibitory domain near its carboxyl terminus. To further characterize this domain, the full-length enzyme as well as a truncated form lacking this domain were expressed in bacterial cells and purified. The full-length enzyme expressed in bacteria exhibits essentially the same biochemical characteristics as the enzyme isolated from Dictyostelium. The truncated form however exhibits a Vmax that is approximately ten times greater than that of the native enzyme. In addition, unlike the native kinase and the full-length kinase expressed in bacteria, the truncated enzyme does not undergo autophosphorylation. These results suggest that the Dictyostelium enzyme, like myosin light chain kinases from higher eukaryotes, is regulated by an autoinhibitory domain but that the specific molecular signals necessary for activation of the Dictyostelium enzyme are entirely distinct.
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Affiliation(s)
- J L Tan
- Department of Cell Biology, Stanford University School of Medicine, California 94305
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Tan JL, Spudich JA. Dictyostelium myosin light chain kinase. Purification and characterization. J Biol Chem 1990; 265:13818-24. [PMID: 2380188] [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] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022] Open
Abstract
A Dictyostelium myosin light chain kinase has been purified approximately 15,000-fold to near homogeneity. The purified kinase is a single polypeptide of approximately 34 kDa that phosphorylates only the 18-kDa Dictyostelium myosin regulatory light chain and itself among substrates tested. The enzyme was purified largely by ammonium sulfate fractionation and hydrophobic (butyl) interaction chromatography. Analysis using polyclonal antibodies raised against the purified 34-kDa protein confirms that this protein is responsible for myosin light chain kinase activity. Protein microsequence of the 34-kDa protein reveals conserved protein kinase sequences. The purified Dictyostelium myosin light chain kinase exhibits a Km for Dictyostelium myosin of 4 microM and a Vmax of 8 nmol/min/mg. Unlike other characterized myosin light chain kinases, this enzyme is not regulated by calcium/calmodulin. Western blot analysis demonstrates that the purified kinase is not a proteolytic fragment that has lost calcium/calmodulin regulation. The Dictyostelium myosin light chain kinase activity is not directly regulated by cyclic nucleotides. However, this kinase undergoes an intramolecular autophosphorylation that activates the enzyme.
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Affiliation(s)
- J L Tan
- Department of Cell Biology, Stanford University School of Medicine, California 94305
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Abstract
Dictyostelium discoideum, an organism that undergoes development and that is amenable to biochemical and molecular genetic approaches, is an attractive model organism with which to study the role of tyrosine phosphorylation in cell-cell communication. We report the presence of protein-tyrosine kinase genes in D. discoideum. Screening of a Dictyostelium cDNA expression library with an anti-phosphotyrosine antibody identifies fusion proteins that exhibit protein-tyrosine kinase activity. Two distinct cDNAs were identified and isolated. Though highly homologous to protein kinases in general, these kinases do not exhibit many of the hallmarks of protein-tyrosine kinases of higher eucaryotes. In addition, these genes are developmentally regulated, which suggests a role for tyrosine phosphorylation in controlling Dictyostelium development.
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Affiliation(s)
- J L Tan
- Department of Cell Biology, Stanford University School of Medicine, California 94305
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Goh KT, Lun KC, Chong YM, Ong TC, Tan JL, Chay SO. Prevalence of respiratory illnesses of school children in the industrial, urban and rural areas of Singapore. Trop Geogr Med 1986; 38:344-50. [PMID: 3810838] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Abstract
An epidemiological survey of 3216 primary school children living in the industrial, urban and rural areas of Singapore revealed a high prevalence of various respiratory symptoms and illnesses, with 13.1% cough, 8.2% wheezy chest, 25.9% blocked/running nose, 4.3% sinusitis, 7.8% asthmatic attacks and 4.1% bronchitis/pneumonia. Differences in the prevalence of respiratory illnesses and lung function tests were observed among children in the three areas, but this could not be accounted for by the varying air pollution levels which have been maintained below the long-term standards set up by WHO. It was probably responsible for the differences noted.
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Abstract
An epidemiological investigation of an outbreak of Vibrio cholerae 01, biotype El Tor, serotype Ogawa, phage type 1, confined to a group of foreign construction workers in Singapore is described. A total of 22 workers were confirmed to have cholera and another 15 had asymptomatic Vibrio cholerae 01 infection between 3 November and 11 November 1982. The source of infection was traced to contaminated seafood prepared at the construction site canteen where two food handlers were found to be infected with V. cholerae 01 (one symptomatic and the other asymptomatic). The incubation period of cholera in this outbreak ranged from 4 to 203 hours with a median of 38 hours. Only two workers had moderate to severe dehydration and required intravenous therapy. Early recognition of the outbreak and prompt implementation of control measures prevented the outbreak from spreading to other parts of Singapore.
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Goh KT, Doraisingham S, Tan JL, Lim GN, Chew SE. An outbreak of hand, foot, and mouth disease in Singapore. Bull World Health Organ 1982; 60:965-9. [PMID: 6297819 PMCID: PMC2535982] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023] Open
Abstract
Epidemiological studies were carried out during an extensive outbreak of hand, foot and mouth disease caused by coxsackievirus A 16 in Singapore in 1981. Most of the cases were concentrated in densely populated public housing estates, and the morbidity rate was highest in children under 5 years of age. The mean secondary attack rate for children under 12 years of age was 76.7% compared with an overall rate of 31.3%. The incubation period ranged from 1 to 7 days. Factors favouring the transmission of infection within a household included sharing of household and personal articles with the index case. The disease was mild and self-limiting.
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