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Ng YH, Chai YC, Mazli N, Jaafar NF, Ibrahim S. Outcome of Endoprosthesis used in Limb Salvage Surgery in a Malaysian Orthopaedic Oncology Centre. Malays Orthop J 2024; 18:60-65. [PMID: 38638655 PMCID: PMC11023336 DOI: 10.5704/moj.2403.008] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2023] [Accepted: 08/14/2023] [Indexed: 04/20/2024] Open
Abstract
Introduction To describe the duration of survival among bone tumour patients with endoprosthesis reconstruction and to determine frequency of implant failure, revision of surgery, and amputation after endoprosthesis reconstruction. Materials and methods A retrospective cross-sectional review of all patients with either primary bone tumour or secondary bone metastases treated with en bloc resection and endoprosthesis reconstruction from January 2008 to December 2020. Results A total of 35 failures were recorded among the 27 (48.2%) patients with endoprostheses. Some of the patients suffered from one to three types of modes of failure on different timelines during the course of the disease. Up to eight patients suffered from more than one type of failure throughout the course of the disease. Out of all modes of failure, local recurrence (type 5 failure) was the most common, accounting for 25.0% of all failure cases. Four patients (7.1%) eventually underwent amputation, which were either due to infection (2 patients) or disease progression causing local recurrence (2 patients). Conclusion The overall result of endoprosthesis reconstruction performed in our centre was compatible with other centres around the world. Moreover, limb salvage surgery should be performed carefully in a selected patient group to maximise the benefits of surgery.
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Affiliation(s)
- Y H Ng
- Department of Orthopaedic, Hospital Sultan Ismail, Johor Bahru, Malaysia
| | - Y C Chai
- General Psychiatry Division, Hospital Permai Johor Bahru, Johor Bahru, Malaysia
| | - N Mazli
- Department of Orthopaedics and Traumatology, Universiti Kebangsaan Malaysia, Kuala Lumpur, Malaysia
| | - N F Jaafar
- Department of Orthopaedic, Hospital Sultan Ismail, Johor Bahru, Malaysia
| | - S Ibrahim
- Department of Orthopaedic, Hospital Sultan Ismail, Johor Bahru, Malaysia
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Ng YH, Okolo CA, Erickson JR, Baldi JC, Jones PP. Protein O-GlcNAcylation in the heart. Acta Physiol (Oxf) 2021; 233:e13696. [PMID: 34057811 DOI: 10.1111/apha.13696] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2021] [Revised: 05/25/2021] [Accepted: 05/27/2021] [Indexed: 12/30/2022]
Abstract
O-GlcNAcylation is a ubiquitous post-translational modification that is extremely labile and plays a significant role in physiology, including the heart. Sustained activation of cardiac O-GlcNAcylation is frequently associated with alterations in cellular metabolism, leading to detrimental effects on cardiovascular function. This is particularly true during conditions such as diabetes, hypertension, cardiac remodelling, heart failure and arrhythmogenesis. Paradoxically, transient elevation of cardiac protein O-GlcNAcylation can also exert beneficial effects in the heart. There is compelling evidence to suggest that a complex interaction between O-GlcNAcylation and phosphorylation also exists in the heart. Beyond direct functional consequences on cardiomyocytes, O-GlcNAcylation also acts indirectly by altering the function of transcription factors that affect downstream signalling. This review focuses on the potential cardioprotective role of protein O-GlcNAcylation during ischaemia-reperfusion injury, the deleterious consequences of chronically elevated O-GlcNAc levels, the interplay between O-GlcNAcylation and phosphorylation in the cardiomyocytes and the effects of O-GlcNAcylation on other major non-myocyte cell types in the heart.
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Affiliation(s)
- Yann Huey Ng
- Department of Medicine and HeartOtago University of Otago Dunedin New Zealand
| | - Chidinma A. Okolo
- Department of Physiology and HeartOtago University of Otago Dunedin New Zealand
- Life Sciences Division Diamond Light Source LtdHarwell Science and Innovation Campus Didcot UK
| | - Jeffrey R. Erickson
- Department of Physiology and HeartOtago University of Otago Dunedin New Zealand
| | - James C. Baldi
- Department of Medicine and HeartOtago University of Otago Dunedin New Zealand
| | - Peter P. Jones
- Department of Physiology and HeartOtago University of Otago Dunedin New Zealand
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Cheok GJW, Gatot C, Sim CHS, Ng YH, Tay KXK, Howe TS, Koh JSB. Appropriate attitude promotes mask wearing in spite of a significant experience of varying discomfort. Infect Dis Health 2021; 26:145-151. [PMID: 33612451 PMCID: PMC7891075 DOI: 10.1016/j.idh.2021.01.002] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2020] [Revised: 12/31/2020] [Accepted: 01/10/2021] [Indexed: 01/23/2023]
Abstract
BACKGROUND Despite increasing evidence to support mask effectiveness in mitigating the spread of COVID-19, there is still raging controversy regarding the use of masks. Evaluation of public perceptions, attitudes and the individuals' experience towards mask-wearing is integral to ensuring reasonable compliance and allows authorities to address concerns held by the population. METHODS A cross-sectional survey of lay-people was conducted within a high volume tertiary level institution in Singapore, from 16 October to 16 November 2020. Surveys administered evaluated five questions: 1) duration of mask wear per day, 2) mask-type used, 3) perceived necessity, 4) discomfort level experienced and 5) causes for discomfort. RESULTS Out of 402 respondents, 67.2% primarily wore disposable surgical masks. 72% felt mask-wearing was necessary to control COVID-19 transmission. 78.4% reported discomfort while wearing masks, with mean discomfort levels of 4.21 out of 10. Impairment to breathing and communication difficulties were the most common discomforts faced. Younger respondents complained of higher incidence of dermatological issues and sweating (p < 0.05). Respondents who wore masks for longer duration reported higher incidence of dermatological issues (p = 0.001) and sweating (p = 0.032). CONCLUSION AND RELEVANCE Even with an available vaccine, adjunctive public health measures such as mask-wearing will likely continue in order to curb COVID-19 transmission. Experience from past pandemics is likely to propagate self-protective behavior within a community. Our study identified several common mask-wearing discomforts, allowing respective organizations valuable market feedback for research and development. With appropriate public attitudes, effective mask-wearing compliance can be attained in a concerted effort against the coronavirus.
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Affiliation(s)
- Gideon J W Cheok
- Department of Orthopaedic Surgery, Singapore General Hospital, Level 4, Academia, 20 College Road, Singapore 169856, Singapore.
| | - Cheryl Gatot
- Department of Orthopaedic Surgery, Singapore General Hospital, Level 4, Academia, 20 College Road, Singapore 169856, Singapore
| | - Craigven H S Sim
- Department of Orthopaedic Surgery, Singapore General Hospital, Level 4, Academia, 20 College Road, Singapore 169856, Singapore
| | - Y H Ng
- Department of Orthopaedic Surgery, Singapore General Hospital, Level 4, Academia, 20 College Road, Singapore 169856, Singapore
| | - Kenny X K Tay
- Department of Orthopaedic Surgery, Singapore General Hospital, Level 4, Academia, 20 College Road, Singapore 169856, Singapore
| | - T S Howe
- Department of Orthopaedic Surgery, Singapore General Hospital, Level 4, Academia, 20 College Road, Singapore 169856, Singapore
| | - Joyce S B Koh
- Department of Orthopaedic Surgery, Singapore General Hospital, Level 4, Academia, 20 College Road, Singapore 169856, Singapore
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Ng YH, Hong CC, Ng DZ, Kumar VP. Percutaneous distal clavicle excision for acromioclavicular joint arthritis: our experience and early results of a novel surgical technique. Musculoskelet Surg 2021; 106:247-255. [PMID: 33759141 DOI: 10.1007/s12306-021-00708-9] [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: 07/29/2020] [Accepted: 03/12/2021] [Indexed: 10/21/2022]
Abstract
PURPOSE Symptomatic acromioclavicular joint (ACJ) osteoarthritis causes pain and limitations in activities of daily living. Open and arthroscopic distal clavicle excision techniques have been described with good outcomes. However, both techniques have their own sets of advantages and disadvantages. This study describes a novel technique of percutaneous distal clavicle excision for symptomatic ACJ osteoarthritis and our two-year results. METHODS Fifteen consecutive patients underwent percutaneous distal clavicle excision for ACJ arthritis. These patients had failed a trial of conservative treatment. The ACJ was confirmed as the pain generator with an intraarticular steroid/lignocaine injection, and shoulder MRI was used to exclude alternative pain generators in the shoulder. They had a minimum of two years of follow-up. RESULTS At a mean of 26.8 months postoperatively, the mean VAS pain score was 0, and the mean Constant score for the shoulder was 87.3 points (range 50-94), which corresponded to 1 good, 1 very good and 13 excellent results. The mean SF-36 score was 94.9 points (range 65-100). There were statistically significant improvements in the VAS scores, Constant shoulder scores and SF-36 scores at one year and two years of follow-up (p < 0.05). Three unique complications, namely subcutaneous emphysema, "missing" of the distal clavicle and thermal skin injury, were encountered. Our surgical technique has since been modified to circumvent these complications. CONCLUSION Our novel technique of percutaneous distal clavicle excision yields a 93.3% good-to-excellent results based on the Constant shoulder score and durable pain relief based on VAS at two years.
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Affiliation(s)
- Y H Ng
- Department of Orthopaedic Surgery, National University Hospital, 1E Kent Ridge Road, Singapore, 119228, Singapore
| | - C C Hong
- Department of Orthopaedic Surgery, National University Hospital, 1E Kent Ridge Road, Singapore, 119228, Singapore.
| | - D Z Ng
- Department of Orthopaedic Surgery, National University Hospital, 1E Kent Ridge Road, Singapore, 119228, Singapore
| | - V P Kumar
- Department of Orthopaedic Surgery, National University Hospital, 1E Kent Ridge Road, Singapore, 119228, Singapore
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Lee AYS, Beroukas D, Brown L, Lucchesi C, Kaur A, Gyedu L, Hughes N, Ng YH, Saran O, Gordon TP, Wang JJ. Identification of a unique anti-Ro60 subset with restricted serological and molecular profiles. Clin Exp Immunol 2020; 203:13-21. [PMID: 32852779 DOI: 10.1111/cei.13508] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [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: 07/07/2020] [Revised: 08/06/2020] [Accepted: 08/14/2020] [Indexed: 12/30/2022] Open
Abstract
Anti-Ro60 is one of the most common and clinically important serum autoantibodies that has a number of diagnostic and predictive capabilities. Most diagnostic laboratories report this simply as a qualitative positive/negative result. The objective of this study was to examine the clinical and serological relevance of a novel subset of anti-Ro60 in patients who display low levels of anti-Ro60 (anti-Ro60low ). We retrospectively identified anti-Ro60 sera during a 12-month period at a major immunopathology diagnostic laboratory in Australia. These all were anti-Ro60-precipitin-positive on the diagnostic gold standard counter-immuno-electrophoresis (CIEP). Lineblot immunoassay was used to stratify patients into either anti-Ro60low or anti-Ro60high subsets. We compared the medical and laboratory parameters associated with each group. Enzyme-linked immunosorbent assay (ELISA) and mass spectrometry techniques were used to analyse the serological and molecular basis behind the two subsets. Anti-Ro60low patients displayed less serological activity than anti-Ro60high patients with less intermolecular spreading, hypergammaglobulinaemia and less tendency to undergo anti-Ro60 isotype-switching than anti-Ro60high patients. Mass spectrometric typing of the anti-Ro60low subset showed restricted variable heavy chain subfamily usage and amino acid point mutations. This subset also displayed clinical relevance, being present in a number of patients with systemic autoimmune rheumatic diseases (SARD). We identify a novel anti-Ro60low patient subset that is distinct from anti-Ro60high patients serologically and molecularly. It is not clear whether they arise from common or separate origins; however, they probably have different developmental pathways to account for the stark difference in immunological maturity. We hence demonstrate significance to anti-Ro60low and justify accurate detection in the diagnostic laboratory.
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Affiliation(s)
- A Y S Lee
- Department of Immunology, SA Pathology and Flinders Medical Centre, Bedford Park, SA, Australia.,College of Medicine and Public Health, Flinders University, Bedford Park, SA, Australia
| | - D Beroukas
- Department of Immunology, SA Pathology and Flinders Medical Centre, Bedford Park, SA, Australia.,College of Medicine and Public Health, Flinders University, Bedford Park, SA, Australia
| | - L Brown
- Department of Immunology, SA Pathology and Flinders Medical Centre, Bedford Park, SA, Australia
| | - C Lucchesi
- Department of Immunology, SA Pathology and Flinders Medical Centre, Bedford Park, SA, Australia
| | - A Kaur
- Department of Immunology, SA Pathology and Flinders Medical Centre, Bedford Park, SA, Australia
| | - L Gyedu
- Department of Immunology, SA Pathology and Flinders Medical Centre, Bedford Park, SA, Australia
| | - N Hughes
- Department of Immunology, SA Pathology and Flinders Medical Centre, Bedford Park, SA, Australia
| | - Y H Ng
- Department of Immunology, SA Pathology and Flinders Medical Centre, Bedford Park, SA, Australia
| | - O Saran
- Department of Immunology, SA Pathology and Flinders Medical Centre, Bedford Park, SA, Australia
| | - T P Gordon
- Department of Immunology, SA Pathology and Flinders Medical Centre, Bedford Park, SA, Australia.,College of Medicine and Public Health, Flinders University, Bedford Park, SA, Australia
| | - J J Wang
- Department of Immunology, SA Pathology and Flinders Medical Centre, Bedford Park, SA, Australia.,College of Medicine and Public Health, Flinders University, Bedford Park, SA, Australia
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Ng YH, Pilcher DV, Bailey M, Bain CA, MacManus C, Bucknall TK. Predicting medical emergency team calls, cardiac arrest calls and re-admission after intensive care discharge: creation of a tool to identify at-risk patients. Anaesth Intensive Care 2018; 46:88-96. [PMID: 29361261 DOI: 10.1177/0310057x1804600113] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
Abstract
We aimed to develop a predictive model for intensive care unit (ICU)-discharged patients at risk of post-ICU deterioration. We performed a retrospective, single-centre cohort observational study by linking the hospital admission, patient pathology, ICU, and medical emergency team (MET) databases. All patients discharged from the Alfred Hospital ICU to wards between July 2012 and June 2014 were included. The primary outcome was a composite endpoint of any MET call, cardiac arrest call or ICU re-admission. Multivariable logistic regression analysis was used to identify predictors of outcome and develop a risk-stratification model. Four thousand, six hundred and thirty-two patients were included in the study. Of these, 878 (19%) patients had a MET call, 51 (1.1%) patients had cardiac arrest calls, 304 (6.5%) were re-admitted to ICU during the same hospital stay, and 964 (21%) had MET calls, cardiac arrest calls or ICU re-admission. A discriminatory predictive model was developed (area under the receiver operating characteristic curve 0.72 [95% confidence intervals {CI} 0.70 to 0.73]) which identified the following factors: increasing age (odds ratio [OR] 1.012 [95% CI 1.007 to 1.017] <i>P</i> <0.001), ICU admission with subarachnoid haemorrhage (OR 2.26 [95% CI 1.22 to 4.16] <i>P</i>=0.009), admission to ICU from a ward (OR 1.67 [95% CI 1.31 to 2.13] <i>P</i> <0.001), Acute Physiology and Chronic Health Evaluation (APACHE) III score without the age component (OR 1.005 [95% CI 1.001 to 1.010] <i>P</i>=0.025), tracheostomy on ICU discharge (OR 4.32 [95% CI 2.9 to 6.42] <i>P</i> <0.001) and discharge to cardiothoracic (OR 2.43 [95%CI 1.49 to 3.96] <i>P</i> <0.001) or oncology wards (OR 2.27 [95% CI 1.05 to 4.89] <i>P</i>=0.036). Over the two-year period, 361 patients were identified as having a greater than 50% chance of having post-ICU deterioration. Factors are identifiable to predict patients at risk of post-ICU deterioration. This knowledge could be used to guide patient follow-up after ICU discharge, optimise healthcare resources, and improve patient outcomes and service delivery.
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Affiliation(s)
- Y H Ng
- School of Nursing and Midwifery, Deakin University, Melbourne, Victoria
| | - D V Pilcher
- The Australian and New Zealand Intensive Care Research Centre, School of Public Health and Preventive Medicine, Monash University, Melbourne, Victoria
| | - M Bailey
- Statistician, The Australian and New Zealand Intensive Care Research Centre, School of Public Health and Preventive Medicine, Monash University, Melbourne, Victoria
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Loi E, Ng RWC, Chang MMF, Fong JFY, Ng YH, Ng SM. One-pot synthesis of carbon dots using two different acids and their respective unique photoluminescence property. LUMINESCENCE 2016; 32:114-118. [DOI: 10.1002/bio.3157] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/22/2015] [Revised: 04/07/2016] [Accepted: 04/11/2016] [Indexed: 11/08/2022]
Affiliation(s)
- Elaine Loi
- Faculty of Engineering, Computing, and Science; Swinburne University of Technology Sarawak Campus; Jalan Simpang Tiga 93350 Kuching Sarawak Malaysia
| | - Roy Wei Chao Ng
- Faculty of Engineering, Computing, and Science; Swinburne University of Technology Sarawak Campus; Jalan Simpang Tiga 93350 Kuching Sarawak Malaysia
| | - Melissa May Fung Chang
- Faculty of Engineering, Computing, and Science; Swinburne University of Technology Sarawak Campus; Jalan Simpang Tiga 93350 Kuching Sarawak Malaysia
- Swinburne Sarawak Research Centre for Sustainable Technologies; Swinburne University of Technology Sarawak Campus; Jalan Simpang Tiga 93350 Kuching Sarawak Malaysia
| | - Jessica Fung Yee Fong
- Faculty of Engineering, Computing, and Science; Swinburne University of Technology Sarawak Campus; Jalan Simpang Tiga 93350 Kuching Sarawak Malaysia
- Swinburne Sarawak Research Centre for Sustainable Technologies; Swinburne University of Technology Sarawak Campus; Jalan Simpang Tiga 93350 Kuching Sarawak Malaysia
| | - Yann Huey Ng
- Faculty of Engineering, Computing, and Science; Swinburne University of Technology Sarawak Campus; Jalan Simpang Tiga 93350 Kuching Sarawak Malaysia
- Swinburne Sarawak Research Centre for Sustainable Technologies; Swinburne University of Technology Sarawak Campus; Jalan Simpang Tiga 93350 Kuching Sarawak Malaysia
| | - Sing Muk Ng
- Faculty of Engineering, Computing, and Science; Swinburne University of Technology Sarawak Campus; Jalan Simpang Tiga 93350 Kuching Sarawak Malaysia
- Swinburne Sarawak Research Centre for Sustainable Technologies; Swinburne University of Technology Sarawak Campus; Jalan Simpang Tiga 93350 Kuching Sarawak Malaysia
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Foo CY, Lim HN, Pandikumar A, Huang NM, Ng YH. Utilization of reduced graphene oxide/cadmium sulfide-modified carbon cloth for visible-light-prompt photoelectrochemical sensor for copper (II) ions. J Hazard Mater 2016; 304:400-408. [PMID: 26595899 DOI: 10.1016/j.jhazmat.2015.11.004] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/22/2015] [Revised: 10/27/2015] [Accepted: 11/04/2015] [Indexed: 06/05/2023]
Abstract
A newly developed CdS/rGO/CC electrode was prepared based on a flexible carbon cloth (CC) substrate with cadmium sulfide (CdS) nanoparticles and reduced graphene oxide (rGO). The CdS was synthesized using an aerosol-assisted chemical vapor deposition (AACVD) method, and the graphene oxide was thermally reduced on the modified electrode surface. The existence of rGO in the CdS-modified electrode increased the photocurrent intensity of the CdS/rGO/CC-modified electrode by three orders of magnitude, compared to that of the CdS/ITO electrode and two orders of magnitude higher than the CdS/CC electrode. A new visible-light-prompt photoelectrochemical sensor was developed based on the competitive binding reaction of Cu(2+) and CdS on the electrode surface. The results showed that the effect of the Cu(2+) on the photocurrent response was concentration-dependent over the linear ranges of 0.1-1.0 μM and 1.0-40.0 μM with a detection limit of 0.05 μM. The results of a selectivity test showed that this modified electrode has a high response toward Cu(2+) compared to other heavy metal ions. The proposed CdS/rGO/CC electrode provided a significantly high potential current compared to other reported values, and could be a practical tool for the fast, sensitive, and selective determination of Cu(2+).
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Affiliation(s)
- C Y Foo
- Department of Chemistry, Faculty of Science, Universiti Putra Malaysia, 43400 Serdang, Selangor, Malaysia
| | - H N Lim
- Department of Chemistry, Faculty of Science, Universiti Putra Malaysia, 43400 Serdang, Selangor, Malaysia; Functional Device Laboratory, Institute of Advance Technology, Universiti Putra Malaysia, 43400 Serdang, Selangor, Malaysia.
| | - A Pandikumar
- Low Dimensional Materials Research Centre, Department of Physics, Faculty of Science, University of Malaya, 50603 Kuala Lumpur, Malaysia
| | - N M Huang
- Low Dimensional Materials Research Centre, Department of Physics, Faculty of Science, University of Malaya, 50603 Kuala Lumpur, Malaysia
| | - Y H Ng
- Particles and Catalysis Research Group, School of Chemical Engineering, The University of New South Wales, NSW 2052, Australia
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Wee SS, Ng YH, Ng SM. Synthesis of fluorescent carbon dots via simple acid hydrolysis of bovine serum albumin and its potential as sensitive sensing probe for lead (II) ions. Talanta 2013; 116:71-6. [PMID: 24148375 DOI: 10.1016/j.talanta.2013.04.081] [Citation(s) in RCA: 156] [Impact Index Per Article: 14.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/05/2013] [Revised: 04/26/2013] [Accepted: 04/30/2013] [Indexed: 11/24/2022]
Abstract
Carbon dots have great potential to be utilised as an optical sensing probe due to its unique photoluminescence and less toxic properties. This work reports a simple and novel synthesis method of carbon dots via direct acid hydrolysis of bovine serum albumin protein in a one-pot approach. Optimisation of the important synthetic parameters has been performed which consists of temperature effect, acid to protein ratio and kinetics of reaction. Higher temperature has promoted better yield with shorter reaction time. The carbon dots obtained shows a strong emission at the wavelength of 400 nm with an optimum excitation of 305 nm. The potential of the carbon dots as optical sensing probe has been investigated on with different cations that are of environmental and health concern. The fluorescence of the carbon dots was significantly quenched particularly by lead (II) ions in a selective manner. Further analytical study has been performed to leverage the performance of the carbon dots for lead (II) ions sensing using the standard Stern-Volmer relationship. The sensing probe has a dynamic linear range up to 6.0 mM with a Stern-Volmer constant of 605.99 M(-1) and a limit of detection (LOD) of 5.05 μM. The probe performance was highly repeatable with a standard deviation below 3.0%. The probe suggested in this study demonstrates the potential of a more economical and greener approach that uses protein based carbon dots for sensing of heavy metal ions.
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Affiliation(s)
- Shui Shui Wee
- Faculty of Engineering, Computing, and Science, Swinburne University of Technology Sarawak Campus, Jalan Simpang Tiga, 93350 Kuching, Sarawak, Malaysia
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Leung YH, Chan CMN, Ng AMC, Chan HT, Chiang MWL, Djurišić AB, Ng YH, Jim WY, Guo MY, Leung FCC, Chan WK, Au DTW. Antibacterial activity of ZnO nanoparticles with a modified surface under ambient illumination. Nanotechnology 2012; 23:475703. [PMID: 23103840 DOI: 10.1088/0957-4484/23/47/475703] [Citation(s) in RCA: 62] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/18/2023]
Abstract
In various practical applications, nanomaterials typically have functionalized surfaces. Yet, the studies of toxicity and antibacterial activity of functionalized nanoparticles are scarce. We investigated the effect of surface modifications on antibacterial activity of ZnO under ambient illumination, and we found that nanoparticles coated with different surface modifying reagents could exhibit higher or lower toxicity compared to bare ZnO, depending on the surface modifying reagent used. Different surface modifying reagent molecules resulted in differences in the release of Zn(2+) ions and the production of reactive oxygen species (ROS). However, the antibacterial activity did not correlate with the ROS levels or the Zn(2+) ion release. One of the surface-modified ZnO samples exhibited significantly lower Zn(2+) ion release while at the same time exhibiting improved antibacterial activity. In all cases, damage of the cell wall membranes and/or changes in the membrane permeability have been observed, together with the changes in ATR-FTIR spectra indicating differences in protein conformation. Mechanisms of antibacterial activity are discussed.
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Affiliation(s)
- Y H Leung
- Department of Physics, The University of Hong Kong, Hong Kong
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Abstract
INTRODUCTION There is a recent surge in interest on bisphosphonate related femoral fractures. Most studies have examined subtrochanteric fractures in patients on long-term bisphosphonates. This study evaluates the characteristics of low-impact femoral shaft fractures in elderly patients on long-term alendronate. MATERIALS AND METHODS All patients above 60 years old admitted to the National University Hospital for femoral shaft fracture from January 2003 to January 2007 were retrospectively analysed. Of the 55 patients included, 7 had prior alendronate therapy and were examined in detail. RESULTS All 7 patients on prior alendronate therapy sustained their fractures by low-impact or atraumatic mechanisms of injury. 5 of these 7 patients exhibited a characteristic fracture pattern of thickened lateral cortices at the proximal fracture fragment (p<0.05) and all 7 patients had either transverse or short oblique fractures. Notably, none of the 7 patients had bone mineral density scans prior to their fractures. One patient was started on alendronate after a vertebral compression fracture, whilst the other 6 patients were started on alendronate without any clear clinical indication. All 7 patients reported prodromal thigh pain 3 weeks to 2 years prior to the fracture. CONCLUSIONS Low-impact femoral shaft fractures in elderly patients on long-term alendronate therapy represent a new entity of insufficiency fractures, with characteristic low-impact modes of injury and fracture patterns on radiograph. Prodromal thigh pain is a warning sign for impending fracture in this group of patients and should be evaluated closely. Teriparatide is a possible alternative to alendronate following such a fracture though more long-term clinical studies are required.
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Affiliation(s)
- Y H Ng
- Department of Orthopaedic Surgery, National University Hospital, 5 Lower Kent Ridge Road, Singapore 119074, Singapore.
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Ng YH, Chong KW, Tan GM, Rao M. Distally pedicled peroneus brevis muscle flap: a versatile lower leg and foot flap. Singapore Med J 2010; 51:339-342. [PMID: 20505914] [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: 05/29/2023]
Abstract
INTRODUCTION The purpose of this study was to evaluate the outcome of our early experience with the distally pedicled peroneus brevis flap in the management of soft tissue defects of the lower leg, ankle and foot. METHODS This was a non-randomised, retrospective study involving five patients who were treated with the peroneus brevis muscle flap for soft tissue defects over the lower leg. RESULTS In all five patients, the flaps were viable and successful in providing satisfactory soft tissue coverage for the defects. In one diabetic patient, distal flap necrosis was observed, which was treated successfully with a local rotational skin flap. CONCLUSION The distally pedicled peroneus brevis muscle flap is an economical, reliable and relatively easy procedure for treating defects of the distal third of the leg, ankle and foot.
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Affiliation(s)
- Y H Ng
- Department of Orthopaedic Surgery, Singapore General Hospital, Outram Road, Singapore 169608.
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Abstract
Disseminated tuberculous lesions post intravesical BCG therapy are rare but need to be identified and treated quickly. We report the first case of a tuberculous cutaneous lesion in a patient receiving the above treatment.
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Affiliation(s)
- Y H Ng
- Department of Urology, Raigmore Hospital, Inverness, UK
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Wen HL, Ho WK, Ling N, Mehal ZD, Ng YH. Immunoassayable beta-endorphin level in the plasma and CSF of heroin addicted and normal subjects before and after electroacupuncture. Am J Chin Med 1980; 8:154-9. [PMID: 6967253 DOI: 10.1142/s0192415x80000104] [Citation(s) in RCA: 25] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
Abstract
The present study was undertaken to evaluate if plasma or CSF beta-endorphin level can be induced to rise during the treatment of heroin addiction by electroacupuncture. Based on the examination of 30 addicts, we obtained no evidence indicating an increase of beta-endorphin level in either the plasma or the CSF after 30 min of acupuncture. In spite of this, the majority of the addicts experienced a reduction of withdrawal symptoms during treatment. Since electroacupuncture may only induce a highly localized secretion of beta-endorphin in the brain, our results cannot unequivocally exclude the possibility that this peptide is involved in mediating the action of acupuncture.
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Wen HL, Lo CW, Ho WK, Mehal ZD, Ng YH, Lam S, Ma L. Naloxone in the treatment of schizophrenia. Mod Med Asia 1978; 14:51-5. [PMID: 750907] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
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16
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Wen HL, Ng YH, Ho WK, Fung KP, Wong HK, Ma L, Wong HC. Acupuncture in narcotic withdrawal: a preliminary report on biochemical changes in the blood and urine of heroin addicts. Bull Narc 1978; 30:31-9. [PMID: 216444] [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: 12/13/2022]
Abstract
Eight female heroin-addicted subjects were treated over a 10-day period by acupuncture and electrical stimulation (AES). Their plasma ACTH, cortisol and c-AMP levels were reduced after initial AES treatment. The reduction of c-AMP was significant the most of the three. The suppression of these compounds may be associated with the temporary relief of withdrawl symptoms on and after each AES treatment in the first three days. On the third day, ACTH, cortisol and c-AMP levels did not show significant changes after AES. This was presumably due to the disappearance of withdrawal symptoms and possibly to the stabilizing effect of the treatment. Both the ACTH and c-AMP levels were generally lower at the end of the treatment period. Results of the present investigation suggest that plasma c-AMP may be the best parameter by which to gauge the response of heroin addicts to AES.
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Wen HL, Ho WK, Wong HK, Mehal ZD, Ng YH, Ma L. Reduction of adrenocorticotropic hormone (ACTH) and cortisol in drug addicts treated by acupuncture and electrical stimulation (AES). Comp Med East West 1978; 6:61-6. [PMID: 213234 DOI: 10.1142/s0147291778000095] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Forty-two heroin addicts and 31 normal persons were examined for the effect of acupuncture and electrical stimulation (AES) on plasma ACTH, cortisol and cyclic-AMP levels. Both ACTH and cortisol levels were reduced significantly in the addicts after treatment whereas no such significant reduction was observed in the normals. Plasma cyclic-AMP level was not affected in either group. Taken together, results from the present study suggest that the mechanism of AES in the treatment of addiction may have a neuroendocrinological basis. This hypothesis is particularly attractive in view of the isolation of opiate-like peptides from the brain.
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Wen HL, Ho WK, Wong HK, Mehal ZD, Ng YH, Ma L. Changes in adrenocorticotropic hormone (ACTH) and cortisol levels in drug addicts treated by a new and rapid detoxification procedure using acupuncture and naloxone. Comp Med East West 1978; 6:241-5. [PMID: 225122 DOI: 10.1142/s0147291778000319] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Plasma ACTH, cortisol, and cyclic-AMP levels of eleven heroin addicts were dertermined before and after treatment with a fast detoxification procedure using acupuncture and electrical stimulation (AES) together with the administration of limited doses of naloxone. At the end of the treatment period, the average plasma ACTH, cortisol, and cyclic-AMP level rose 130,83, and 24 percent, respectively. In view of the appearance of mild withdrawal signs during this method of treatment, the observed increases in ACTH and cortisol levels probably reflect the inability of AES to suppress withdrawal symptoms induced by naloxone completely. The mechanism underlying this new method of treatment is discussed in relation to AES's ability to stimulate the secretion of endorphins.
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Abstract
The serum concentrations of ACTH, cortisol, aldosterone, thyroxine, cyclic AMP and cholesterol were compared between normal and heroin-addicted subjects. Significantly lower ACTH, cyclic AMP and cholesterol levels were observed to be associated with the heroin addicts, but their plasma thyroxine level was significantly elevated. The possible physiopsychological effect resulting from these changes is discussed.
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