MyMedR

Fulltext Novel anode catalyst for direct methanol fuel cells

Basri S, Kamarudin SK, Daud WR, Yaakob Z, Kadhum AA

ScientificWorldJournal, 2014;2014:547604.

PMID: 24883406 DOI: 10.1155/2014/547604

PtRu catalyst is a promising anodic catalyst for direct methanol fuel cells (DMFCs) but the slow reaction kinetics reduce the performance of DMFCs. Therefore, this study attempts to improve the performance of PtRu catalysts by adding nickel (Ni) and iron (Fe). Multiwalled carbon nanotubes (MWCNTs) are used to increase the active area of the catalyst and to improve the catalyst performance. Electrochemical analysis techniques, such as energy dispersive X-ray spectrometry (EDX), X-ray diffraction (XRD), field emission scanning electron microscopy (FESEM), and X-ray photoelectron spectroscopy (XPS), are used to characterize the kinetic parameters of the hybrid catalyst. Cyclic voltammetry (CV) is used to investigate the effects of adding Fe and Ni to the catalyst on the reaction kinetics. Additionally, chronoamperometry (CA) tests were conducted to study the long-term performance of the catalyst for catalyzing the methanol oxidation reaction (MOR). The binding energies of the reactants and products are compared to determine the kinetics and potential surface energy for methanol oxidation. The FESEM analysis results indicate that well-dispersed nanoscale (2-5 nm) PtRu particles are formed on the MWCNTs. Finally, PtRuFeNi/MWCNT improves the reaction kinetics of anode catalysts for DMFCs and obtains a mass current of 31 A g(-1) catalyst.

Fulltext Pachydermodactyly does not need rheumatologic work-up

Sinha NK, Ling SP, Nema SK, Pai DR

J Postgrad Med, 2013 Oct-Dec;59(4):335-6.

PMID: 24346401 DOI: 10.4103/0022-3859.123182

Fulltext A rare case of Dysphagia secondary to a large oesophageal lipoma

Koh KS, Chong VH, Yapp SK, Chong CF

Med J Malaysia, 2012 Oct;67(5):522-3.

PMID: 23770871

Dysphagia is considered a warning symptom that requires exclusion of significant pathology such as oesophageal cancer, especially in elderly patients. Benign neoplasms of the oesophagus are rare. We report the case of a 69-year-old lady who presented with a five years history of infrequent intermittent dysphagia that had rapidly progressed over one month. This was associated with globus sensation, weight loss, intermittent episodes of stridor and aspiration pneumonia. Investigations revealed a large oesophageal lipoma in the proximal oesophagus extending down to the lower oesophagus. This was successfully resected via a left cervical approach. She remained well two years after the surgery.

Human mesenchymal stromal cells could deliver erythropoietin and migrate to the basal layer of hair shaft when subcutaneously implanted in a murine model

Mok PL, Cheong SK, Leong CF, Chua KH, Ainoon O

Tissue Cell, 2012 Aug;44(4):249-56.

PMID: 22560724 DOI: 10.1016/j.tice.2012.04.002

Mesenchymal stromal cells (MSC) are an attractive cell-targeting vehicle for gene delivery. MIDGE (an acronym for Minimalistic, Immunologically Defined Gene Expression) construct is relatively safer than the viral or plasmid expression system as the detrimental eukaryotic and prokaryotic gene and sequences have been eliminated. The objective of this study was to test the ability of the human MSC (hMSC) to deliver the erythropoietin (EPO) gene in a nude mice model following nucleofection using a MIDGE construct. hMSC nucleofected with MIDGE encoding the EPO gene was injected subcutaneously in Matrigel at the dorsal flank of nude mice. Subcutaneous implantation of nucleofected hMSC resulted in increased hemoglobin level with presence of human EPO in the peripheral blood of the injected nude mice in the first two weeks post-implantation compared with the control groups. The basal layer of the hair shaft in the dermal layer was found to be significantly positive for immunohistochemical staining of a human EPO antibody. However, only a few basal layers of the hair shaft were found to be positively stained for CD105. In conclusion, hMSC harboring MIDGE-EPO could deliver and transiently express the EPO gene in the nude mice model. These cells could be localized to the hair follicle and secreted EPO protein might have possible role in hair regeneration.

Fulltext Care of severe head injury patients in the Sarawak General Hospital: intensive care unit versus general ward

Sim SK, Lim SL, Lee HK, Liew D, Wong A

Med J Malaysia, 2011 Jun;66(2):138-41.

PMID: 22106695 MyJurnal

Intensive care for severe head injury patients is very important in the prevention and treatment of secondary brain injury. However, in a resources constraint environment and limited availability of Intensive Care Unit (ICU) beds in the hospitals, not all severe head injury patients will receive ICU care. This prospective study is aimed to evaluate the outcome of severe head injured patients who received ICU and general ward care in Sarawak General Hospital (SGH) over a 6-month period. A total of thirty five severe head injury patients were admitted. Twenty three patients (65.7%) were ventilated in general ward whereas twelve patients (34.3%) were ventilated in ICU. Overall one month mortality in this study was 25.7%. Patients who received ICU care had a lower one month mortality than those who received general ward care (16.7% vs 30.4%), although it was not statistically different. Multivariate analysis revealed only GCS on admission (OR 0.731; 95% CI 0.460 to 0.877; P=0.042) as the independent predictive factor for one month mortality in this study.

Fulltext Extended and stable gene expression via nucleofection of MIDGE construct into adult human marrow mesenchymal stromal cells

Mok PL, Cheong SK, Leong CF, Chua KH, Ainoon O

Cytotechnology, 2012 Mar;64(2):203-16.

PMID: 22160354 DOI: 10.1007/s10616-011-9413-2

Human mesenchymal stromal cell (hMSC) is a potential target for cell and gene therapy-based approaches against a variety of different diseases. Whilst cationic lipofection has been widely experimented, the Nucleofector technology is a relatively new non-viral transfection method designed for primary cells and hard-to-transfect cell lines. Herein, we compared the efficiency and viability of nucleofection with cationic lipofection, and used the more efficient transfection method, nucleofection, to deliver a construct of minimalistic, immunologically defined gene expression encoding the erythropoietin (MIDGE-EPO) into hMSC. MIDGE construct is relatively safer than the viral and plasmid expression systems as the detrimental eukaryotic and prokaryotic gene and sequences have been eliminated. Using a plasmid encoding the luciferase gene, we demonstrated a high transfection efficiency using the U-23 (21.79 ± 1.09%) and C-17 (5.62 ± 1.09%) pulsing program in nucleofection. The cell viabilities were (44.93 ± 10.10)% and (21.93 ± 5.72)%, respectively 24 h post-nucleofection. On the other hand, lipofection treatment only yielded less than 0.6% efficiencies despite showing higher viabilities. Nucleofection did not affect hMSC renewability, immunophenotype and differentiation potentials. Subsequently, we nucleofected MIDGE-EPO using the U-23 pulsing program into hMSC. The results showed that, despite a low nucleofection efficiency with this construct, the EPO protein was stably expressed in the nucleofected cells up to 55 days when determined by ELISA or immunocytochemical staining. In conclusion, nucleofection is an efficient non-viral transfection approach for hMSC, which when used in conjunction with a MIDGE construct, could result in extended and stable transgene expression in hMSC.

Fulltext Recurrent multiple myeloma presenting as a breast plasmacytoma

Kalyani A, Rohaizak M, Cheong SK, Nor Aini U, Balasundaram V, Norlia A

Med J Malaysia, 2010 Sep;65(3):227-8.

PMID: 21939175

We describe a patient with multiple myeloma, who initially responded to chemotherapy and went into remission. She presented 10 months later with a right breast lump which was confirmed by core biopsy to be a plasmacytoma. Further treatment with radiotherapy, thalidomide and later second line chemotherapy appeared unsuccessful and she showed rapid disease progression with rising paraproteins and new extramedullary plasmacytoma lesions in the forehead, supraclavicular region, nasopharynx, liver, spleen, pancreas and paraaortic lymph nodes.

Platelet-rich plasma (PRP) enhances bone healing in non-united critical-sized defects: a preliminary study involving rabbit models

Kanthan SR, Kavitha G, Addi S, Choon DS, Kamarul T

Injury, 2011 Aug;42(8):782-9.

PMID: 21329922 DOI: 10.1016/j.injury.2011.01.015

The use of bone grafts in treating non- or delayed unions as the result of large bone loss is well established. However, despite good outcomes, the time to achieve complete union is still considerably long. To overcome this problem, the use of platelet-rich plasma (PRP) has been advocated albeit with varying success. To determine the true effectiveness of PRP in treating non-/delayed unions, a study was conducted using (n=12) rabbit models.

Fulltext Childhood idiopathic myelofibrosis: a case report and review of literature

Noor-Fadzilah Z, Leong CF, Sabariah MN, Cheong SK

Malays J Pathol, 2009 Dec;31(2):129-32.

PMID: 20514856 MyJurnal

Idiopathic myelofibrosis occurs predominantly in older adults. It is very rarely seen in children. We describe a 3-year-old girl with Down's syndrome who presented with recurrent chest infections associated with anaemia and easy bruising. There was mild hepatosplenomegaly. Full blood picture revealed pancytopaenia with leucoerythroblastosis with absence of circulating blast cells. Repeated attempts at bone marrow aspiration and trephine biopsy were unsuccessful. A trephine biopsy from the tibia showed depressed myelopoiesis and erythropoiesis, megakaryocytes with atypical morphology and increased bone marrow reticulin fibres, findings compatible with idiopathic myelofibrosis. She was treated symptomatically as she was clinically stable. Review of the English literature online yielded 46 reported cases of childhood idiopathic myelofibrosis with variable outcome from spontaneous remission to an indolent course with shortened survival. 6 cases evolved to another malignancy. 5 cases were associated with Down's syndrome.

Cytochrome P450 3A4 genetic polymorphisms and post-operative fentanyl requirements

Tan PC, Hassan SK, Mohamad NA, Gan SH

J Clin Pharm Ther, 2012 Feb;37(1):100-4.

PMID: 21128989 DOI: 10.1111/j.1365-2710.2010.01232.x

WHAT IS KNOWN AND OBJECTIVE: Interindividual variability in drug responses may be attributable to genetically determined alteration in enzyme activity. In this study, we investigated the association between cytochrome P450 3A4 (CYP3A4) genetic polymorphisms and post-operative fentanyl requirements.

METHODS: Patients (n = 94) scheduled for gynaecological laparotomy received i.v. fentanyl infusion (3 μg/kg/h) after induction of general anaesthesia. Post-operative fentanyl requirements were quantified by using a patient-controlled analgesia and the number of i.v. fentanyl rescue analgesia required were recorded. Pain control was assessed using visual analogue scores (VAS) and fentanyl's adverse effects were documented. CYP3A4*4, CYP3A4*5 and CYP3A4*18 alleles of cytochrome P450 3A4 were identified by polymerase chain reaction-restriction fragment length polymorphism. Differences in fentanyl requirements, VAS scores and adverse effects among the various genotypes were compared.

RESULTS AND DISCUSSION: No CYP3A4*4 and CYP3A4*5 alleles were detected. Eighty-nine patients (94·7%) were wild-type, five (5·3%) were heterozygous and none was homozygous. No significant difference was demonstrated between the genotype groups in terms of fentanyl consumption, pain control and adverse effects.

WHAT IS NEW AND CONCLUSION: CYP3A4*4 and CYP3A4*5 are rare in the Malaysian Malay population. Genetic polymorphism of CYP3A4*18 may not play an important role in influencing postoperative fentanyl requirements.

Fulltext Endoscopic nasopharyngectomy: the Sarawak experience

Rohaizam J, Subramaniam SK, Vikneswaran T, Tan VE, Tan TY

Med J Malaysia, 2009 Sep;64(3):213-5.

PMID: 20527270 MyJurnal

Shifting the paradigm of treatment of a locally recurrent nasopharyngeal carcinoma (NPC) from the non-surgical management to a surgical modality has always been a challenge. However, many studies on endoscopic nasopharyngectomy have proven it to be a reliable form of treatment with an excellent outcome. Since 2007, in Sarawak General Hospital, six cases of endoscopic nasopharyngectomy for locally recurrent NPC have been performed with encouraging results.

Physicochemical and sensory properties of ice-cream formulated with virgin coconut oil

Choo SY, Leong SK, Henna Lu FS

Food Sci Technol Int, 2010 Dec;16(6):531-41.

PMID: 21339169 DOI: 10.1177/1082013210367546

The substitution of milk fat with virgin coconut oil (VCO) was used to produce nutritious ice cream with pleasant coconut flavor and aroma. Three formulations were developed whereby formulation VCO4, VCO8 and VCO12 was substituted with 4%, 8% and 12% of VCO, respectively. The physicochemical properties of ice creams analyzed include overrun, meltdown, pH, titratable acidity, total solid, protein and fat content. The fatty acids profile of VCO formulated ice creams and their stabilities over 3 and 6 weeks storage were studied respectively using gas chromatography (GC). Qualitative descriptive analysis (QDA) and consumer affective test were performed among the trained and untrained panelists. Significant differences (p < 0.05) of overrun, pH, total solid, protein and fat content between ice cream formulations were observed except titratable acidity. Increased VCO content in ice cream formulations lowered the melting resistance of ice cream. For GC analysis, the major fatty acid identified was lauric acid. Upon storage time, the concentration of unsaturated fatty acid decreased but the concentration of saturated fatty acid increased. The result of QDA showed that formulation VCO4, VCO8 and VCO12 were significantly (p < 0.05) different in attributes of color, firmness and smoothness as compared to the control ice cream. Formulation VCO12 was highly accepted by panelists in terms of the acceptance level of appearance, aroma, texture, flavor and overall acceptability. Hence, it has a potential marketable value.

Mini open carpal tunnel release using Knifelight: evaluation of the safety and effectiveness of using a single wrist incision (cadaveric study)

Teh KK, Ng ES, Choon DS

J Hand Surg Eur Vol, 2009 Aug;34(4):506-10.

PMID: 19675032 DOI: 10.1177/1753193409100962

This cadaveric study evaluates the margin of safety and technical efficacy of mini open carpal tunnel release performed using Knifelight (Stryker Instruments) through a transverse 1 cm wrist incision. A single investigator released 32 wrists in 17 cadavers. The wrists were then explored to assess the completeness of release and damage to vital structures including the superficial palmar arch, palmar cutaneous branch and recurrent branch of the median nerve. All the releases were complete and no injury to the median nerve and other structures were observed. The mean distance of the recurrent motor branch to the ligamentous divisions was 5.7 +/- 2.4 mm, superficial palmar arch was 8.7 +/- 3.1 mm and palmar cutaneous branch to the ligamentous division was 7.2 +/- 2.4 mm. The mean length of the transverse carpal ligament was 29.3 +/- 3.7 mm. Guyon's canal was preserved in all cases.

Fulltext Stem cell transplantation in Malaysia and future directions

Fadilah SA, Leong CF, Cheong SK

Med J Malaysia, 2008 Oct;63(4):279-80.

PMID: 19385484 MyJurnal

Validation of the drinking refusal self-efficacy questionnaire in Arab and Asian samples

AlMarri TS, Oei TP, AbRahman RM

Addict Behav, 2009 Sep;34(9):776-8.

PMID: 19481874 DOI: 10.1016/j.addbeh.2009.05.009

The influence of an individuals' belief in their ability to resist drinking alcohol has recognised importance in understanding the pattern of drinking behaviours among Caucasian samples. Measures used to investigate this construct, such as the drinking refusal self-efficacy questionnaire-revised (DRSEQ-R; [Oei, T. P. S., Hasking, P. A., & Young, R. M. (2005). Drinking refusal self-efficacy questionnaire-revised (DRSEQ-R): A new factor structure with confirmatory factor analysis. Drug and Alcohol Dependence, 78, 297-307.]) have been widely used and have established psychometric properties. However, the exploration of the utility of this questionnaire with samples of different ethnicity, religion and living in different countries remains scarce. In the current study, Arab Muslim samples living in the United Arab Emirates and Oman (n=356) and Asian predominately Muslim samples living in Malaysia and Indonesia (n=256) were used. Exploratory and confirmatory factor analysis demonstrated that the DRSEQ-R has a three factor structure. Internal consistency ranged from alpha .96 to alpha .86 and validity was good. This study offers evidence of the utility of this measure with Arab and Asian samples.

Immunogenic properties of recombinant ectodomain of Newcastle disease virus hemagglutinin-neuraminidase protein expressed in Escherichia coli

Wong SK, Tan WS, Omar AR, Tan CS, Yusoff K

Acta Virol., 2009;53(1):35-41.

PMID: 19301949

Hemagglutinin-neuraminidase (HN) protein of Newcastle disease virus (NDV) plays a vital role in the viral infectivity, host immunity, and disease diagnosis. A portion of the HN gene encoding the ectodomain (nt 142-1739) was cloned and expressed in Escherichia coli yielding an insoluble HN protein and a soluble NusA-HN protein containing N-utilization substance A (NusA) fusion component. Both recombinant proteins were purified and used for immunization of chickens. The recombinant HN protein induced higher antibody titers as compared to the recombinant NusA-HN protein. These antibodies were able to react in immunoblot analysis with the corresponding recombinant proteins as well as with the HN protein of NDV.

Fulltext Candida sake--a rare cause of fungal endocarditis

Anuradha S, Agarwal SK, Prakash A, Singh NP, Kaur R

Med J Malaysia, 2008 Mar;63(1):75-6.

PMID: 18935744

Midterm outcome of the Duracon total knee arthroplasty

Yong CK, Choon DS, Soon HC

J Orthop Surg (Hong Kong), 2008 Aug;16(2):197-200.

PMID: 18725672

To present midterm results of Duracon total knee arthroplasty (TKA) performed between 1991 and 2001.

Fulltext Cerebellopontine angle medulloblastoma

Nyanaveelan M, Azmi A, Saffari M, Banu SK, Suryati MY, Jeyaledchumy M

Med J Malaysia, 2007 Jun;62(2):173-4.

PMID: 18705459 MyJurnal

An extremely rare case of a right cerebellopontine angle medulloblastoma in a five year old Malay girl which had eroded into the petrous bone and extended into the temporal fossa is reported. Combined subtemporal and retromastoid approach to achieve gross total surgical resection was achieved followed by radiotherapy and chemotherapy.

In vitro expression of erythropoietin by transfected human mesenchymal stromal cells

Mok PL, Cheong SK, Leong CF, Othman A

Cytotherapy, 2008;10(2):116-24.

PMID: 18368590 DOI: 10.1080/14653240701816996

Mesenchymal stromal cells (MSC) are pluripotent progenitor cells that can be found in human bone marrow (BM). These cells have low immunogenicity and could suppress alloreactive T-cell responses. In the current study, MSC were tested for their capacity to carry and deliver the erythropoietin (EPO) gene in vitro.

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