Rahman Jamal

Dengue epidemic in Malaysia: Not a predominantly urban disease anymore

BackgroundDengue infection has been an important and serious public health concern in Malaysia ever since its first reported case here in 1902. Nevertheless, to our knowledge, no nationwide investigation has been carried out to determine the actual magnitude of dengue endemicity in the Malaysian population. In this study, we describe a cross sectional seroepidemiology study of dengue IgG seroprevalence in the Malaysian adult population.FindingsFrom 1000 subjects (35-74 years old), 91.6% subjects were found to be dengue seropositive. Age is found to be a significant risk factor associated with dengue seroposivity, where the seroprevalence increased with every 10 year increase in age. Nevertheless, gender and ethnicity did not have an effect. Interestingly, there were similar seroprevalence rates between urban and rural samples, showing that dengue is presently not confined to urban areas in Malaysia.ConclusionsHigh dengue IgG seropositivity found in the population is an indication that dengue might be endemic in Malaysia for a long time into the future. Public awareness, proper vector control and vigilant surveillance are critical to keep the infection rates low and to prevent outbreaks.

Antibacterial performance of Ag nanoparticles and AgGO nanocomposites prepared via rapid microwave-assisted synthesis method

Silver nanoparticles and silver-graphene oxide nanocomposites were fabricated using a rapid and green microwave irradiation synthesis method. Silver nanoparticles with narrow size distribution were formed under microwave irradiation for both samples. The silver nanoparticles were distributed randomly on the surface of graphene oxide. The Fourier transform infrared and thermogravimetry analysis results showed that the graphene oxide for the AgNP-graphene oxide (AgGO) sample was partially reduced during the in situ synthesis of silver nanoparticles. Both silver nanoparticles and AgGO nanocomposites exhibited stronger antibacterial properties against Gram-negative bacteria (Salmonella typhi and Escherichia coli) than against Gram-positive bacteria (Staphyloccocus aureus and Staphyloccocus epidermidis). The AgGO nanocomposites consisting of approximately 40 wt.% silver can achieve antibacterial performance comparable to that of neat silver nanoparticles.

Prevalence and parental perceptions of complementary and alternative medicine use by children with cancer in a multi-ethnic Southeast Asian population

The purpose of the current study was to determine the prevalence of use of complementary and alternative medicine (CAM) by children with cancer and to compare the characteristics of CAM users and CAM nonusers.

An unusual mutation in RECQ4 gene leading to Rothmund–Thomson syndrome

Rothmund-Thomson syndrome (OMIM #268400) is a severe autosomal recessive genodermatosis: characterised by growth retardation, hyperpigmentation and frequently accompanied by congenital bone defects, brittle hair and hypogonadism. Mutations in helicase RECQ4 gene are responsible for a subset of cases of RTS. Only six mutations have been reported, thus, far and each affecting the coding sequence or the splice junctions. We report the first homozygous mutation in RECQ4 helicase: 2746-2756-delTGGGCTGAGGC in IVS8 responsible for the severe phenotype associated with RTS in a Malaysian pedigree. We report also a 5321 G-->A transition in exon 17 and the updated list of the RECQ4 gene mutations.

Salvage of patients with acute promyelocytic leukaemia with residual disease following ABMT performed in second CR using all-trans retinoic acid

Detection of residual disease after completion of therapy or following bone marrow transplantation (BMT) in patients with acute promyelocytic leukaemia (APL) predicts relapse and is associated with a poor prognosis. Here we describe the successful treatment of residual disease post‐transplant in APL using prolonged all‐trans retinoic acid (ATRA) therapy in two children in whom autologous BMT (ABMT) had been performed in second complete remission (CR). ATRA treatment was well tolerated and found to be beneficial despite its prior use as a component of the initial induction protocol. ATRA therapy post‐transplant led to molecular remission as determined by fluorescence in situ hybridization (FISH) as well as reverse transcriptase‐polymerase chain reaction (RT‐PCR) analyses and remission now exceeds 3.5 years in both patients. Overall, this study not only demonstrates that ATRA may successfully salvage APL patients with residual disease post‐transplant, but also suggests a potential role for retinoids post‐consolidation as a means of eliminating residual disease which could be beneficial even in patients previously exposed to ATRA as a component of the induction protocol.

The role of long chain omega-3 polyunsaturated fatty acids in reducing lipid peroxidation among elderly patients with mild cognitive impairment: a case-control study

The present work explores the effect of dietary omega-3 polyunsaturated fatty acids (PUFAs) intake on lipid peroxidation among mild cognitive impairment (MCI) patients. The plasma lipid hydroperoxide (LPO) levels in 67 MCI patients were compared to those of 134 healthy elderly controls. Omega-3 PUFA intake was assessed using an interviewer-administered food frequency questionnaire. Apolipoprotein E genotyping was performed using polymerase chain reaction and restriction enzyme digestion. The association between various confounders and lipid peroxidation was evaluated using regression analysis. The influence of docosahexaenoic acid (DHA) and eicosapentaenoic acid (EPA) intake on LPO level was investigated. The results revealed that LPO levels were significantly higher in the MCI group than in the control group. Inverse correlations were found between DHA and EPA intake and LPO level among the MCI group. LPO levels decreased significantly with increasing DHA and EPA intake. In summary, the findings revealed that DHA and EPA can play a role in alleviating oxidative stress and reducing the risk of neurodegenerative diseases.

Microarray profiling of secretory-phase endometrium from patients with recurrent miscarriage

The aim of the present study was to identify differentially expressed genes and their related biological pathways in the secretory phase endometrium from patients with recurrent miscarriage (RM) and fertile subjects. Endometrial samples from RM and fertile patients were analyzed using the Affymetrix GeneChip® ST Array. The bioinformatic analysis using the Partek Genomic Suite revealed 346 genes (175 up-regulated and 171 down-regulated) that were differentially expressed in the endometrium of RM patients compared to the fertile subjects (fold change ≥1.5, p<0.005). Validation step using quantitative real-time polymerase chain reaction (qPCR) confirmed a similar expression pattern of four exemplary genes: one up-regulated gene (fibroblast growth factor 9, FGF9) and three down-regulated genes: integrin β3 (ITGB3), colony stimulating factor 1 (CSF1) and matrix-metalloproteinases 19 (MMP19). The Gene Set Enrichment Analysis (GSEA) and the Pathway Studio software have found 101 signaling pathways (p<0.05) associated with the affected genes including the FGFR3 /signal transducer and activator of transcription (STAT) pathway and the CSF1R/STAT pathway. Cell adhesion, cell differentiation and angiogenesis were among biological processes indicated by this system. In conclusion, microarray technique is a useful tool to study gene expression in the secretory phase-endometrium of RM patients. The differences in endometrial gene expressions between healthy and RM subjects contribute to an increase in our knowledge on molecular mechanisms of RM development and may improve the outcome of pregnancies in high-risk women with RM.

Integrated analysis of copy number variation and genome-wide expression profiling in colorectal cancer tissues.

Integrative analyses of multiple genomic datasets for selected samples can provide better insight into the overall data and can enhance our knowledge of cancer. The objective of this study was to elucidate the association between copy number variation (CNV) and gene expression in colorectal cancer (CRC) samples and their corresponding non-cancerous tissues. Sixty-four paired CRC samples from the same patients were subjected to CNV profiling using the Illumina HumanOmni1-Quad assay, and validation was performed using multiplex ligation probe amplification method. Genome-wide expression profiling was performed on 15 paired samples from the same group of patients using the Affymetrix Human Gene 1.0 ST array. Significant genes obtained from both array results were then overlapped. To identify molecular pathways, the data were mapped to the KEGG database. Whole genome CNV analysis that compared primary tumor and non-cancerous epithelium revealed gains in 1638 genes and losses in 36 genes. Significant gains were mostly found in chromosome 20 at position 20q12 with a frequency of 45.31% in tumor samples. Examples of genes that were associated at this cytoband were PTPRT, EMILIN3 and CHD6. The highest number of losses was detected at chromosome 8, position 8p23.2 with 17.19% occurrence in all tumor samples. Among the genes found at this cytoband were CSMD1 and DLC1. Genome-wide expression profiling showed 709 genes to be up-regulated and 699 genes to be down-regulated in CRC compared to non-cancerous samples. Integration of these two datasets identified 56 overlapping genes, which were located in chromosomes 8, 20 and 22. MLPA confirmed that the CRC samples had the highest gains in chromosome 20 compared to the reference samples. Interpretation of the CNV data in the context of the transcriptome via integrative analyses may provide more in-depth knowledge of the genomic landscape of CRC.

Vincristine-induced vocal cord palsy: case report and review of the literature.

Vincristine-induced vocal cord paralysis is a rare but serious complication. We report 2 patients with acute lymphoblastic leukemia who developed progressive stridor during induction chemotherapy. There were no clinical features of peripheral or autonomic neuropathy. Flexible laryngoscopy confirmed the diagnosis of bilateral vocal cord palsy; interestingly, the nerve conduction test revealed axonal motor neuropathy involving the median and common peroneal nerves in both patients. The first patient required prolonged ventilatory support necessitating unilateral cordectomy before extubation, whereas the second only required supplemental oxygen therapy. There was resolution of stridor in the first patient after cordectomy and gradual clinical improvement in the second. These cases illustrate that a high index of suspicion of vincristine-induced vocal cord palsy with prompt otolaryngology consultation for laryngoscopy is required in the diagnostic evaluation of a patient who has received vincristine.

Circular RNAs as Promising Biomarkers: A Mini-Review

The interest in circular RNAs has resurfaced in the past few years. What was considered as “junk” for nearly two decades is now one of the most interesting molecules. Circular RNAs are non-coding RNAs that are formed by back-splicing events and have covalently closed loops with no poly-adenylated tails. The regulation of circular RNAs is distinctive and they are selectively abundant in different types of tissues. Based on the current knowledge of circular RNAs, these molecules have the potential to be the “next big thing” especially as biomarkers for different diseases. This mini-review attempts to concisely look at the biology of circular RNAs, the putative functional activities, the prevalence of circular RNAs, and the possible role of circular RNA as biomarkers for diagnosis or measuring drug response.