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Quantification of bioregeneration of activated carbon and activated rice husk loaded with phenolic compounds

Ng SL, Seng CE, Lim PE

Chemosphere, 2009 Jun;75(10):1392-400.
PMID: 19307013 DOI: 10.1016/j.chemosphere.2009.02.049

The bioregeneration efficiencies of powdered activated carbon (PAC) and pyrolyzed rice husk loaded with phenol and p-nitrophenol were quantified by oxygen uptake measurements using the respirometry technique in two approaches: (i) simultaneous adsorption and biodegradation and (ii) sequential adsorption and biodegradation. It was found that the applicability of the simultaneous adsorption and biodegradation approach was constrained by the requirement of adsorption preceding biodegradation in order to determine the initial adsorbent loading accurately. The sequential adsorption and biodegradation approach provides a good estimate of the upper limit of the bioregeneration efficiency for the loaded adsorbent in the simultaneous adsorption and biodegradation processes. The results showed that the mean bioregeneration efficiencies for PAC loaded with phenol and p-nitrophenol, respectively, obtained using the two approaches were in good agreement.
Bioregeneration of activated carbon and activated rice husk loaded with phenolic compounds: Kinetic modeling

Ng SL, Seng CE, Lim PE

Chemosphere, 2010 Jan;78(5):510-6.
PMID: 20035966 DOI: 10.1016/j.chemosphere.2009.11.041

A kinetic model consisting of first-order desorption and biodegradation processes was developed to describe the bioregeneration of phenol- and p-nitrophenol-loaded powdered activated carbon (PAC) and pyrolyzed rice husk (PRH), respectively. Different dosages of PAC and PRH were loaded with phenol or p-nitrophenol by contacting with the respective phenolic compound at various concentrations. The kinetic model was used to fit the phenol or p-nitrophenol concentration data in the bulk solution during the bioregeneration process to determine the rate constants of desorption, k(d), and biodegradation, k. The results showed that the kinetic model fitted relatively well (R(2)>0.9) to the experimental data for the phenol- and p-nitrophenol-loaded PAC as well as p-nitrophenol-loaded PRH. Comparison of the values of k(d) and k shows that k is much greater than k(d). This indicates clearly that the desorption process is the rate-determining step in bioregeneration and k(d) can be used to characterize the rate of bioregeneration. The trend of the variation of the k(d) values with the dosages of PAC or PRH used suggests that higher rate of bioregeneration can be achieved under non-excess adsorbent dosage condition.
Fulltext Audit of perioperative blood transfusion

Choy YC, Lim WL, Ng SH

Med J Malaysia, 2007 Oct;62(4):299-302.
PMID: 18551933 MyJurnal

The main goal of perioperative transfusion is to reduce the morbidity and mortality associated with inadequate delivery of oxygen to the tissues during surgery. In this audit, the primary trigger for transfusion was clinical anaemia assessed by examination of a patient's conjunctiva [40.7%] followed by estimation of blood loss of greater 20% of total blood volume [29.3%]. Haemoglobin estimation in the operation theater was not done in 45.9% of studied patients and only 7.8% patients had transfusion based on this criteria. A common practice is to transfuse blood for hypovolaemia. This was the indication for blood transfusion in 96 patients (7.8%). Inappropriate use of blood in this way has led to wastage of a valuable resource and exposed patients to potential risks of unwanted side effects. Analysis of haemoglobin estimation at recovery room showed 32% of patient with co-morbidities had Hb > 10 gm% while 65% and 29.5% of patients without co-morbidities had Hb > 8 gm% and 10 gm% respectively. This reflects the practice of anaesthetists in maintaining a target of Hb of 10 gm% for both groups of patients while a target of 8 gm% is still relatively safe for patients with good cardiovascular reserves. This has resulted in signifant use of homologous blood which will certainly burden the blood bank and increase the cost of healthcare.
Fulltext Quantitative and qualitative evaluation of sural nerve graft donor site

Ng SS, Kwan MK, Ahmad TS

Med J Malaysia, 2006 Dec;61 Suppl B:13-7.
PMID: 17600987

This study is designed to evaluate twenty patients after sural nerve harvest using the single longitudinal incision method. The area of sensory loss to pin prick was assessed by the authors at different intervals. Donor site factors, scar cosmesis, functional status and complications were assessed using a questionnaire. The mean area of anaesthesia at one month was 65 cm2 and it had reduced by 77% to 15 cm2 at one and a half years. The mean area of reduced sensation was 49 cm2 at one month and it increased by 18% to 58 cm2 over the same period. Therefore, the total area of sensory deficit was reduced by 36% from 114 cm2 at one month to 73 cm2 at one and a half years. Subjective patient evaluation indicated moderate level of pain during immediate post surgical period, which reduced significantly at one month. A low level of neuroma symptoms was recorded throughout the study period. At a mean follow-up period of two years, there was no area of anaesthesia in 50% of the patients. Mean area of anaesthesia for all patients was 12 cm2 and mean area of reduced sensation was 55 cm2. Subjective patient evaluation indicated a low level of pain, neuroma symptoms and numbness over the sural nerve sensory distribution. Twenty five percent of the patients were not satisfied with the scar appearance. Function and daily activities were not affected significantly. No surgical complications were observed.
Fulltext Temporal bone squamous cell carcinoma - Penang experience

Ng SY, Pua KC, Zahirrudin Z

Med J Malaysia, 2015 Dec;70(6):367-8.
PMID: 26988214 MyJurnal

Temporal bone squamous cell carcinoma (TBSCC) is rare and poses difficulties in diagnosing, staging and management. We describe a case series with six patients who were diagnosed TBSCC, from January 2009 to June 2014, with median age of 62 years old. All patients presented with blood-stain discharge and external auditory canal mass, showing that these findings should highly alert the diagnosis of TBSCC. Three patients staged T3 and another three with T4 disease. High-resolution CT (HRCT) temporal findings were noted to be different from intraoperative findings and therefore we conclude that MRI should be done to look for middle ear involvement or other soft tissue invasion for more accurate staging. Lateral temporal bone resection (LTBR) and parotidectomy was done for four patients with or without neck dissection. Patients with positive margin, perineural invasion or parotid and glenoid involvement carry poorer prognosis and postoperative radiotherapy may improve the survival rate. One patient had successful tumor resection via piecemeal removal approach in contrast with the recommended en bloc resection shows that with negative margin achieved, piecemeal removal approach can be a good option for patients with T2-3 disease. In general, T4 tumor has dismal outcome regardless of surgery or radiotherapy given.
Therapeutic and reproductive cloning--implications and recommendations

Ng SC, Ng Y, Liow SL, Chen N

Med J Malaysia, 2003 Mar;58 Suppl A:102-10.
PMID: 14556357

The announcement of Dolly's birth took the world by storm, mainly because what was thought impossible has become possible. Optimism that new approaches in agriculture and medicine abound, as much as fear and imagination leading to Frankenstein-like scenarios. Scientifically, cloning refers to replicating an animal with the same nuclear genetic material; whilst it may refer to embryos as the source material, the current storm refers to differentiated ("somatic") cells. Cloning technology is useful in the following areas: agriculture, to produce animals of superior or specific qualities; endangered animals, to increase genetic diversity through widening the gene pool; understanding fundamental questions in developmental embryology, through the use of laboratory animals; and in human therapy, to produce cells and possibly tissues for repair and regeneration. In the first 2 instances, it is reproductive cloning. In the last instance, it is therapeutic cloning, as no individuals are "produced". Human reproductive cloning is not allowed by all governments that have deliberated on it, and therapeutic cloning is allowed by some under certain circumstances. As therapeutic cloning has great potential in cures of many diseases, it should be allowed but with safeguards to prevent abuse and reproductive cloning in the human.
Fulltext Airway stenting for tracheal stenosis

Eng JB, Hooi LN, Ng SH

Med J Malaysia, 1999 Mar;54(1):125-7.
PMID: 10972017

Patients with upper airway obstruction from malignant disease are difficult to manage. A 62 year old patient presented with stridor and was found to have an upper tracheal tumour. Bronchoscopy, dilatation and stenting were performed successfully. The techniques and indications for the use of dynamic airway stent are discussed.
Proteus syndrome

Ng SC, Khoo BS, Ho NK

J Paediatr Child Health, 1997 Jun;33(3):264-6.
PMID: 9259308

This female Asian (Malay) baby had clinical features of Proteus syndrome. She had a large right facial lipolymphangioma with hyperpigmentation of the overlying skin. There was a smaller lymphangioma over the left side of her neck with excess nuchal folds, macrodactyly and bilateral talipes equinovarus. Despite the extensive hemifacial swelling, there was no evidence of upper respiratory tract obstruction. Generalized seizures developed on the sixth day of life which were controlled with phenobarbital. The lymphangiomas were excised without recurrence.
Effect of the oral contraceptive pill on protein S and antithrombin-III levels in Malaysian women

Wong KK, Ng SC, Koong PL

Med Sci Res, 1992 Jun;20(12):439-40.
PMID: 12288974
Acquired platelet dysfunction with eosinophilia in white children

Poon MC, Ng SC, Coppes MJ

J Pediatr, 1995 Jun;126(6):959-61.
PMID: 7776107

Acquired platelet dysfunction associated with eosinophilia has been described mainly in indigenous Southeast Asian and East Indian children. We describe two white boys in whom this disorder developed after they had lived in Malaysia for 12 to 18 months. Acquired platelet dysfunction associated with eosinophilia should therefore be considered in children who, after a visit to this region, have easy bruising and esoinophilia.
Autoimmune haemolytic anaemia in pregnancy: a case report

Ng SC, Wong KK, Raman S, Bosco J

Eur J Obstet Gynecol Reprod Biol, 1990 Oct;37(1):83-5.
PMID: 2376282

A young primigravida had idiopathic warm antibody (IgG) autoimmune haemolytic anaemia (AIHA) occurring in the third trimester of pregnancy. Her haemolytic process was responsive to steroid therapy and no transfusion was needed. She delivered a healthy baby with no evidence to haemolysis, though his red cells were coated with IgG which was probably of maternal origin.
Acute organic brain syndrome due to drug-induced eosinophilia

Ng SC, Lee MK, Teh A

Postgrad Med J, 1989 Nov;65(769):843-4.
PMID: 2616421

A 72 year old man developed acute organic brain syndrome associated with marked eosinophilia following self medication with a variety of drugs. Investigations revealed no other known causes of eosinophilia. Withdrawal of drugs resulted in dramatic drop in eosinophil count paralleled by clinical resolution of neurological problems. To our knowledge drug-induced eosinophilia has not previously been associated with acute organic brain syndrome.
Hybrid acute leukaemia--a report of 3 cases

Ng SC, Wong TK, Lin HP

Ann Acad Med Singap, 1989 Nov;18(6):721-3.
PMID: 2624424

The simultaneous expression of both lymphoid and myeloid phenotypic features in acute leukaemia is rare. We report 3 cases of biphenotypic hybrid acute leukaemia seen in our institution. All 3 patients achieved remission with treatment for acute lymphoblastic leukaemia but two subsequently relapsed while on treatment. The hybrid acute leukaemias are important areas for further research both for delineation of basic biology and choice of optimal treatment.
Fulltext What is the Quality of Life of Transtibial Amputees in Brunei Darussalam?

Ng SS, Naing L, Idris FI, Pande K

Malays Orthop J, 2020 Jul;14(2):39-46.
PMID: 32983376 DOI: 10.5704/MOJ.2007.009

Introduction: Lower limb amputations have a profound impact on the quality of life (QoL) of the patients. This study was done to assess the QoL of patients with transtibial (below-the-knee) amputations (TTA) and transtibial amputees fitted with prosthesis.
Material and Methods: A case-control study of patients who had undergone TTA from 2015 to 2018 was conducted in Raja Isteri Pengiran Anak Saleha Hospital (RIPAS). Complete data was available for 30 subjects and it was compared with 30 diabetic, non-amputee patients matched for age and gender. QoL was assessed using the RAND 36-Item Health Survey (SF-36) and the functional outcome of prosthesis-fitted transtibial amputees was assessed using the Houghton Scale.
Results: Almost all cases of TTA were a result of vascular problems related to diabetes and chronic renal disease (n=29; 97%). Eighteen (60%) participants were fitted with prosthesis and 15 (50%) reported having phantom pain. QoL of participants was found to be significantly lower than that of age and sex-matched diabetic non-amputees with regards to physical functioning, role limitation due to physical health, emotional well-being, social functioning, and bodily pain. The mean Houghton Score for participants fitted with prosthesis was 4.89 (SD= 2.83) suggesting low functional outcome.
Conclusion: TTA has a negative impact on the QoL of patients, especially in terms of functionality. The availability of prosthesis does not significantly improve the quality of life except in the physical functioning domain. Emotional well-being should be emphasised more in the rehabilitation process as this study found poor emotional well-being among participants.
Fulltext The spectrum of elderly myopathies in an Asian population

Ng S, Wong, KT, Goh KJ

Neurology Asia, 2013;18(2):177-181.
MyJurnal

Myopathies, although presenting more commonly in the younger age group, can occur and contribute significantly to disability in the elderly. To describe the spectrum of elderly myopathies, we reviewed 52 elderly patients (> 65 years) from the University of Malaya Medical Centre muscle biopsy databank, constituting 6.8% of 759 adult patients (> 18 years) who underwent muscle biopsy between 1992 and 2012. Commonest were the inflammatory myopathies (41/52, 78.8%), of which 43.9% had dermatomyositis; 23.9% polymyositis; 14.6% sporadic inclusion body myositis; 9.8% undifferentiated myositis and 2.4% overlap myositis. Seven patients (13.4%) had genetic myopathy; 2 muscular dystrophy and 5 chronic progressive external ophthalmoplegia, while 4 patients (7.7%) had drug-associated myopathy, 3 with statins. Malignancies were seen in 9.8% of inflammatory myopathies at diagnosis. Both acquired and genetic myopathies are seen in elderly Malaysians of all ethnicities and should not be misdiagnosed as some are potentially treatable and/or associated with malignancy.
Comparison between FEV1/FEV6 and FEV1/FVC as screening of chronic obstructive pulmonary disease

Ng SC, Abu Samah F, Helmy K, Sia KK

Med J Malaysia, 2017 10;72(5):286-290.
PMID: 29197884 MyJurnal

OBJECTIVE: To compare FEV1/FEV6 to the standard spirometry (FEV1/FVC) as a screening tool for COPD.
METHODS: This cross-sectional study was conducted at Hospital Tuanku Fauziah, Perlis, Malaysia from August 2015 to April 2016. FEV1/FEV6 and FEV1/FVC results of 117 subjects were analysed. Demographic data and spirometric variables were tabulated. A scatter plot graph with Spearman's correlation was constructed for the correlation between FEV1/FEV6 and FEV1/FVC. The sensitivity, specificity, positive and negative predictive values of FEV1/FEV6 were determined with reference to the gold standard of FEV1/FVC ratio <0.70. Receiver-operator characteristic (ROC) curve analysis and Kappa statistics were used to determine the FEV1/FEV6 ratio in predicting an FEV1/FVC ratio <0.70.
RESULTS: Spearman's correlation with r = 0.636 (P<0.001) was demonstrated. The area under the ROC curve was 0.862 (95% confidence interval [CI]: 0.779 - 0.944, P<0.001). The FEV1/FEV6 cut-off with the greatest sum of sensitivity and specificity was 0.75. FEV1/FEV6 sensitivity, specificity, positive and negative predictive values were 93.02%, 67.74%, 88.89% and 77.78% respectively. There was substantial agreement between the two diagnostic cut-offs (κ = 0.634; 95% CI: 0.471 - 0.797, P<0.001) CONCLUSIONS: The FEV1/FEV6 ratio can be considered to be a good alternative to the FEV1/FVC ratio for screening of COPD. Larger multicentre study and better education on spirometric techniques can validate similar study outcome and establish reference values appropriate to the population being studied.
Fulltext Myelodysplastic syndrome: a review from University Hospital, Kuala Lumpur

Ng SC, Kuperan P, Bosco J, Menaka N

Singapore Med J, 1990 Apr;31(2):153-8.
PMID: 2196685

Twenty patients with Myelodysplastic Syndrome (MDS) were diagnosed in University Hospital, Kuala Lumpur over a 5 year period. They were subclassified using the French American British (FAB) criteria. 90% of the patients were above 40 years old and the sex ratio was about equal. The predominant presenting symptom was anaemia and there was paucity of physical signs at presentation. Patients with 'aggressive' subtypes of MDS i.e. refractory anaemia with excess blasts (RAEB), refractory anaemia with excess blasts in transformation (RAEB(-)+) and chronic myelomonocytic leukaemia (CMML) had more frequent thrombocytopenia and neutropenia and their marrow pictures frequently had dysmegakaryopoiesis and dysgranulopoiesis as compared to more the "benign" subtypes i.e. refractory anaemia (RA) and refractory leukaemic anaemia with ringed sideroblasts (RARS). Four patients had leukaemic transformation and all of them came from the 'aggressive' subtypes. The current views on treatment of MDS are discussed.
Fulltext Splenic lymphoma with hypersplenism--a case report

Ng SC, Kuperan P, Jayalakshmi P, Chua CT

Singapore Med J, 1990 Feb;31(1):80-2.
PMID: 2185555

A 47-year old man had hypersplenism from massive splenomegaly, the cause of which was undetermined for 2 years. He was initially asymptomatic though there was mild pancytopenia. However, 18 months after presentation he manifested both clinical and haematological deterioration, almost succumbing to sepsis. Splenectomy finally provided a definite diagnosis of follicular lymphoma and also restored his blood counts to within normal range.
Hydrogen bonding in 2,2,2-trifluoroethanol

Ng S, Xie Y, Schaefer HF

J Mol Model, 2024 Sep 14;30(10):333.
PMID: 39276285 DOI: 10.1007/s00894-024-06135-4

CONTEXT: 2,2,2-Trifluoroethanol (TFE) is known as a membrane mimetic solvent. The IR spectrum, 1H NMR spectrum, 13C NMR spin‒lattice relaxation times (T1), and nuclear Overhauser effect (NOE) data are consistent with extensive hydrogen bonding in TFE, but do not lead to structural features of the hydrogen bonding. Hence, DFT computations were carried out. The results predict the existence of a set of H-bonded dimers and trimers. The bond lengths and dihedral angles in these complexes are obtained, together with their dissociation energies. Computations were also performed for the geometry of the two conformers of the isolated monomer. The structure of one of the dimers consists of a 7-member cyclic fragment with a free CF3CH2 side chain. One set of the trimer structures involves the OH of a third monomer H-bonding to one of the F atoms in the CF3 group of the side chain of this dimer, thereby creating three trimer isomers. A fourth trimer cluster is formed from three monomers in which three OH∙∙∙O bonds create a cyclic fragment with three CF3CH2 side chains. The high dissociation energy (with respect to three monomers) indicates the high stability of the trimer complexes. The structural features of the trimer complexes resemble the structure of a conventional liquid crystal molecule and are postulated to resemble the latter in properties and function in solution, but at a much shorter timescale because of the noncovalent bonding. This hydrogen bonding phenomenon of TFE may be related to its function as a membrane memetic solvent.
METHODS: Initially, IR and NMR spectroscopic methods were used. Standard procedures were followed. For the computations, a hybrid DFT method with empirical dispersion, ωB97X-D, was used. The basis set, 6-311++G**, is of triple-ζ quality, in which polarization functions and diffuse functions were added for all atoms.
Type 3 diabetes (Alzheimer's disease): new insight for promising therapeutic avenues

Candasamy M, Mohamed Elhassan SA, Kumar Bhattamisra S, Hua WY, Sern LM, Binti Busthamin NA, et al.

Panminerva Med, 2020 Sep;62(3):155-163.
PMID: 32208408 DOI: 10.23736/S0031-0808.20.03879-3

Alzheimer's disease (AD) and type 2 diabetes mellitus (T2D) are two of the most commonly occurring diseases worldwide, especially among the elderly population. In particular, the increased prevalence of AD has imposed tremendous psychological and financial burdens on society. Growing evidence suggests both AD and T2D share many similar pathological traits. AD is characterized as a metabolic disorder whereby the glucose metabolism in the brain is impaired. This closely resembles the state of insulin resistance in T2D. Insulin resistance of the brain has been heavily implicated two prominent pathological features of AD, Aβ plaques and neurofibrillary tangles. Brain insulin resistance is known to elicit a positive feed-forward loop towards the formation of AD pathology in which they affect each other in a synergistic manner. Other physiological traits shared between the two diseases include inflammation, oxidative stress and autophagic dysfunction, which are also closely associated with brain insulin resistance. In this review and depending on these underlying pathways that link these two diseases, we have discussed the potential therapeutic implications of AD. By expanding our knowledge of the overlapping pathophysiology involved, we hope to provide scientific basis to the discovery of novel therapeutic strategies to improve the clinical outcomes of AD in terms of diagnosis and treatment.

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