1.Net charge, hydrophobicity and specific amino acids contribute to the activity of antimicrobial peptides.
Jindal MH ; Le CF ; Mohd Yusof MY ; Sekaran SD
Journal of University of Malaya Medical Centre 2014;17(1):1-7
Antimicrobial peptides (AMPs) have gained increasing attention as a potential candidate in the development
of novel antimicrobial agent. Designing AMPs with enhanced antimicrobial activity while reducing the cell
toxicity level is desired especially against the antibiotic-resistant microbes. Various approaches towards the
design of AMPs have been described and physicochemical properties of AMPs represent the primary factors
determining the antimicrobial potency of AMPs. The most common parameters include net charge and
hydrophobicity, which greatly influence the antimicrobial activity of AMPs. Moreover, certain amino acids
would have critical importance in affecting the antimicrobial activity as well as cell cytotoxicity of AMPS. In this
review, net charge, hydrophobicity, and specific amino acid residues were discussed as factors contributing
to the antimicrobial activity of AMPs.
Anti-Infective Agents
2.Autologous chondrocyte implantation for knee focal cartilage defects: 3 years' follow-up at the University Malaya Medical Centre.
Abbas Aa ; Mohamad Ja ; Lydia Al ; Selvaratnam L ; Razif A ; Ab-Rahim S ; kavitha G ; Shilpa Pn ; Kamarul T
Journal of University of Malaya Medical Centre 2014;17(1):8-13
Autologous chondrocyte implantation (ACI) is a widely accepted procedure for the treatment of large, fullthickness
chondral defects involving various joints, but its use in developing countries is limited because of high
cost and failure rates due to limited resources and support systems. Five patients (age <45 years) with focal
cartilage defects received ACI at University of Malaya from 2006 to 2007 and followed up for 36 months. The
average presubjective Knee Evaluation Forms (IKDC) improved from 38.44±6.29 to 25.6±8.04 postoperatively,
the Oxford Knee Score (OKS) went from 25.6±8.04 to 13.96±1.63 and the American Knee Society Score (AKSS)
improved from 80±14.33 to 92.96±5.82 post-operatively. Thus improvements were seen in the IKDC and
AKSS score but not in the OKS. Magnetic resonance images showed the presence of cartilage tissue filling in
the lateral and medial patellar facet and medial femoral condyle in three patients. Failures were seen in two
patients, both with patellar defects and over the age of 36 years. Treatment with autologous chondrocyte
implantation for focal cartilage defect in lateral and medial patellar facet and medial femoral condyle showed
early improvement which was maintained at 3 yrs follow-up. ACI provided satisfactory outcome in focal cartilage
defects involving the femoral condyle.
Chondrocytes
3.Dengue: an overview
Sekaran SD ; Rathakrishnan A ; Yeo ASL
Journal of University of Malaya Medical Centre 2014;17(2):23-32
Dengue is one of the highest occurring vector-borne diseases. It is caused by dengue viruses 1- 4. Currently,
the disease is classified into dengue with or without warning signs and severe dengue based on WHO 2009
dengue classification. As of today, neither specific drugs nor commercial vaccine exist for dengue. The best
treatment yet would be support, management and proper medical care. With no pathognomonic features
that could differentiate it from other febrile illnesses, clinical diagnosis alone is insufficient. Yet, despite the
current advances and existence of various laboratory diagnostic methods of dengue, a consensus singular
method has not been established. There are several hypotheses or theories regarding the vaguely understood
immunopathogenesis of dengue. Amongst these are the viral factors, host-immune factors and host-genetic
factors. In addition to these, the occurrence of asymptomatic dengue has further complicated the disease.
However, these individuals provide opportunities in the search for protective factors against dengue.
Dengue
4.Phyllanthus sp a local plant with multiple medicinal properties
Tang YQ ; Lee SH ; Sekaran SD
Journal of University of Malaya Medical Centre 2014;17(2):1-8
The plants of the genus Phyllanthus (Euphorbiaceae) are distributed in most tropical and subtropical regions
of world. This plant has been long used as a traditional medicine to treat problems such as stomach, intestinal
infections, kidney and urinary bladder disturbances, diabetes, and hepatitis B. There has been considerable
interest in these plants in recent years. This review discusses the antiviral and anticancer aspects of Phyllanthus
species. Scientific studies have demonstrated that extracts and purified isolated compounds (flavonoids,
lignans, phenols, and terpenes) obtained from these plants possess antiviral effects against herpes simplex
(HSV) and dengue virus infections (DENV). These observations are associated with the disruption of essential
proteins needed during viral cycle, thus halting the viral replication. In addition, the Phyllanthus species have
also been shown to exert inhibitory effects against selected cancers types. In these studies anti-proliferative,
anti-metastatic, anti-angiogenic effects and induced apoptosis of human cancers cell lines were observed.
These may be explained by the disruption of multiple survival pathways and differential protein expression.
CONLCUSION:As a conclusion, tThe Phyllanthus plant possesses multiple medicinal properties, including
antiviral and anticancer activities which may potentially be used as a medicinal source for many disease locally.
Antineoplastic Agents
;
Dengue
5.Cell-based therapy for the treatment of focal articular cartilage lesions: a review of six years of studies in a Malaysian University Medical Centre
Journal of University of Malaya Medical Centre 2014;17(2):1-11
Autologous chondrocyte implantation (ACI) is a significant technique that has gained widespread use for the
treatment of focal articular cartilage damage. Since its inception in 2004, the Tissue Engineering Group (TEG)
of the Faculty of Medicine, University Malaya has been dedicated to carrying out extensive research on this
cell-based therapy. The objective of this report, comprising one clinical case report, six animal studies and
one laboratory study, is to summarise and discuss TEG’s key findings. On the whole, we observed that the
ACI technique was effective in regenerating hyaline-like cartilage in treated defects. Autologous chondrocytes
and mesenchymal stem cells (MSC) were found to produce comparable tissue repair irrespective of the state
of MSC differentiation, and the use of alginate-based scaffolding and oral pharmacotherapy (Glucosamine
and Chondroitin Sulphate) was shown to enhance ACI-led tissue repair. ACI is suggested to be an efficient
therapeutic option for the treatment of articular cartilage defects of the knee.
Cartilage, Articular
6.The relevance of micrornas in vascular aging
Journal of University of Malaya Medical Centre 2014;17(2):1-6
MicroRNAs (miRNAs) are short, single-stranded non-coding RNAs that control gene expression by annealing
to complementary sequences in mRNAs. They are estimated to regulate at least one third of human
transcripts and hence, manipulation of these miRNAs can profoundly affect the proteome and ultimately
cellular phenotypes. A substantial amount of work has shed light on the crucial roles of miRNAs in diseases.
miRNA expression profiles between normal and diseased tissues have identified miRNA signature patterns
that correlate to disease development and progression. This review discusses some of the important miRNAs
that are involved in endothelial cell senescence and dysfunction that contribute to the development and
progression of cardiovascular diseases.
MicroRNAs
7.Preliminary study on the occurrence of pten and PIK3CA gene mutations in endometrial cancer among Malaysian women
Subramaniam KS ; Wong MS ; Woo Yl ; Mat Adenan NA ; Mohamed Z ; Chung
Journal of University of Malaya Medical Centre 2013;16(1):1-5
Genetic mutations in endometrial cancer (EC) have been extensively studied in the Western population but
not much in Asian cohorts. This study has demonstrated that PTEN and PIK3CA mutations are commonly
found in EC among Malaysian women. Following RNA extraction from 20 cancerous and 18 non-cancerous
tissues, the presence of mutations in 9 exons of PTEN and 3 exons of PIK3CA genes were detected using realtime
PCR, accompanied by High Resolution Melt (HRM) analysis. Sequencing confirmed specificity of each
PCR product. The mutations for both genes were detected in the samples with varying frequencies. Notably,
all samples expressed mutation of PTEN at exon 7 but none in exon 4. Further analysis demonstrated that
strong concurrent mutations occurred between exons 7 of PTEN with exon 20 region 1 of PIK3CA gene (90%).
Our data showed mutations are present in EC and not the non-cancerous tissues. Larger samples are being
collected to validate this observation.
Uterine Neoplasms
8.Method comparison studies in medicine
Rafdzah Z ; Bulgiba A ; Ismail NA
Journal of University of Malaya Medical Centre 2013;16(1):1-7
Most of important variables measured in medicine are in numerical forms or continuous in nature. New
instruments and tests are constantly being developed for the purpose of measuring various variables, with the aim
of providing cheaper, non-invasive, more convenient and safe methods. When a new method of measurement
or instrument is invented, the quality of the instrument has to be assessed. Agreement and reliability are both
important parameters in determining the quality of an instrument. This article will discuss some issues related
to methods comparison study in medicine for the benefit of medical professional and researcher.
METHOD:
This is a narrative review and this article review the most common statistical methods used to assess agreement
and reliability of medical instruments that measure the same continuous outcome. The two methods discussed
in detail were the Bland-Altman Limits of Agreement, and Intra-class Correlation Coefficient (ICC). This article
also discussed some issues related to method comparison studies including the application of inappropriate
statistical methods, multiple statistical methods, and the strengths and weaknesses of each method. The
importance of appropriate statistical method in the analysis of agreement and reliability in medicine is also
highlighted in this article.
CONCLUSION:
There is no single perfect method to assess agreement and reliability; however researchers should be aware
of the inappropriate methods that they should avoid when analysing data in method comparison studies.
Inappropriate analysis will lead to invalid conclusions and thus validated instrument might not be accurate
or reliable. Consequently this will affect the quality of care given to a patient.
Costs and Cost Analysis
9.Superior somatic pain relief and improved visceral pain control is achieved using pre-emptive analgesia for laparoscopic cholecystectomy: a randomized controlled trial
Koh PS ; Cha KH ; Lucy C ; Rampal S ; Yoong BK
Journal of University of Malaya Medical Centre 2012;15(2):1-7
BACKGROUND:
Laparoscopic cholecystectomy, although is less invasive than open surgery, is not completely pain free. The
use of local anaesthesia to relieve pain following this procedure is a common practice. However, it remains
debatable whether a pre- or post-operative drug administration is more effective. Here, we investigated
the role of preemptive local anaesthetic infiltration given pre- or post-incisional, in relieving the pain during
laparoscopic surgery.
METHODOLOGY:
A randomized controlled trial was conducted with 96 patients receiving 0.5% Bupivacaine 100mg. Group
A (n=48) received post-incisional skin infiltration whilst Group B (n=48) received pre-incisional infiltration.
Incisional (somatic) and intra-abdominal (visceral) pain was assessed using Visual Analog Scale (VAS) at day
0, day 1 and day 7 post-operative days.
RESULT:
Baseline characteristics between the two groups were similar. Incisional pain was lower in Group B as compared
to Group A at day 0 (P=0.03) and day 1 (P<0.01). Intra-abdominal pain was also lower in Group B at day 0 and
day 1 (P= 0.04). VAS score was similar at day 7 although analgesia requirement is higher in Group A (P>0.05).
CONCLUSION:
Administration of pre-incisional local anaesthesia offers better pre-emptive pain relief measure than postincisional
administration by reducing somatic and visceral pain in laparoscopic gall bladder surgery.
Cholecystectomy, Laparoscopic
10.Proteomics of chondrogenesis: a review
Journal of University of Malaya Medical Centre 2015;18(1):1-8
Osteoarthritis (OA) affects millions of people worldwide with its irreversible destruction of articular cartilage.
Recently, the potential of using chondrogenic differentiated multipotent mesenchymal stromal cells (cMSCs)
for OA treatment is being assessed. Preliminary clinical studies have been encouraging. However current
studies have also demonstrated that cMSCs are not biochemically and biomechanically identical to native
articular chondrocytes (ACs). Thus, there is an urgent need for the implementation of proteomic applications
as proteomics involve protein identification, relative quantification of proteins and studies of post-translational
modification which reveal novel regulating processes of complex mechanisms such as in chondrogenesis. A
comprehensive understanding of chondrogenesis is essential for the establishment of an effective cMSC model
to regenerate cartilage. In this article, we will review current proteomic studies on chondrogenesis, focusing
on recent findings and the proteomic approaches utilised.
Chondrocytes