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  1. Molecular detection of Candidatus Anaplasma camelii in camels (Camelus dromedarius) from Asir Province, Saudi Arabia
    Alshahrani MY, Alanazi AD, Alouffi AS, Abdullah HHAM, Allam AM, Mahmoud MS, et al.
    Trop Biomed, 2020 Sep 01;37(3):587-598.
    PMID: 33612774 DOI: 10.47665/tb.37.3.587
    Knowledge of molecular identification of tick-borne pathogens in camels in Saudi Arabia is very limited; few molecular epidemiological studies have been under taken. This study was to detect Anaplasma spp. and Piroplasma spp. in camels from Asir Province, Saudi Arabia. A total of 150 blood samples were collected from camels in Asir Province and investigated by polymerase chain reaction (PCR) that targeted 18S rRNA and 23S rRNA to detect the DNA of Piroplasma spp. and Anaplasma spp., respectively. The positive samples for 23S rRNA were assayed again by PCR targeting the 16S rRNA. All the blood samples were free from Piroplasma spp. infection. Three camels (2%) were found to be positive for Anaplasma infection through use of PCR that targeted the 23S rRNA gene. There were no significant differences between ages or sexes in the camels that tested positive for Anaplasma. All positive Anaplasma infections were recorded in camels that were infested by ticks. Two Anaplasma sequences for the16S rRNA gene were deposited in GenBank with accession numbers MN882724 and MN882725. They recorded 99.16% and 99.34% similarities (respectively) with KF843825.1 (Candidatus Anaplasma camelii reported in Unizah, Saudi Arabia). Phylogenetic analyses revealed that the two sequences recorded in this study were close to each other; both were located in one cluster with Candidatus Anaplasma camelii isolates that were recorded before in the adjacent areas of Unizah in Saudi Arabia and Iran. In conclusion: two new Anaplasma genotypes close to Candidatus Anaplasma camelii were found in camels in Asir Province, Saudi Arabia for the first time. The camels in this province were found to be free of Piroplasma infection.
    Matched MeSH terms: DNA
  2. Fulltext Soup to Tree: The Phylogeny of Beetles Inferred by Mitochondrial Metagenomics of a Bornean Rainforest Sample
    Crampton-Platt A, Timmermans MJ, Gimmel ML, Kutty SN, Cockerill TD, Vun Khen C, et al.
    Mol Biol Evol, 2015 Sep;32(9):2302-16.
    PMID: 25957318 DOI: 10.1093/molbev/msv111
    In spite of the growth of molecular ecology, systematics and next-generation sequencing, the discovery and analysis of diversity is not currently integrated with building the tree-of-life. Tropical arthropod ecologists are well placed to accelerate this process if all specimens obtained through mass-trapping, many of which will be new species, could be incorporated routinely into phylogeny reconstruction. Here we test a shotgun sequencing approach, whereby mitochondrial genomes are assembled from complex ecological mixtures through mitochondrial metagenomics, and demonstrate how the approach overcomes many of the taxonomic impediments to the study of biodiversity. DNA from approximately 500 beetle specimens, originating from a single rainforest canopy fogging sample from Borneo, was pooled and shotgun sequenced, followed by de novo assembly of complete and partial mitogenomes for 175 species. The phylogenetic tree obtained from this local sample was highly similar to that from existing mitogenomes selected for global coverage of major lineages of Coleoptera. When all sequences were combined only minor topological changes were induced against this reference set, indicating an increasingly stable estimate of coleopteran phylogeny, while the ecological sample expanded the tip-level representation of several lineages. Robust trees generated from ecological samples now enable an evolutionary framework for ecology. Meanwhile, the inclusion of uncharacterized samples in the tree-of-life rapidly expands taxon and biogeographic representation of lineages without morphological identification. Mitogenomes from shotgun sequencing of unsorted environmental samples and their associated metadata, placed robustly into the phylogenetic tree, constitute novel DNA "superbarcodes" for testing hypotheses regarding global patterns of diversity.
    Matched MeSH terms: Sequence Analysis, DNA
  3. Complete genome sequence of plant growth-promoting and heavy metal-tolerant Enterobacter tabaci 4M9 (CCB-MBL 5004)
    Abdullahi S, Haris H, Zarkasi KZ, Amir HG
    J Basic Microbiol, 2021 Apr;61(4):293-304.
    PMID: 33491813 DOI: 10.1002/jobm.202000695
    Enterobacter tabaci 4M9 (CCB-MBL 5004) was reported to have plant growth-promoting and heavy metal tolerance traits. It was able to tolerate more than 300 mg/L Cd, 600 mg/L As, and 500 mg/L Pb and still maintained the ability to produce plant growth-promoting substances under metal stress conditions. To explore the genetic basis of these beneficial traits, the complete genome sequencing of 4M9 was carried out using Pacific Bioscience (PacBio) sequencing technology. The complete genome consisted of one chromosome of 4,654,430 bp with a GC content of 54.6% and one plasmid of 51,135 bp with a GC content of 49.4%. Genome annotation revealed several genes involved in plant growth-promoting traits, including the production of siderophore, indole acetic acid, and 1-aminocyclopropane-1-carboxylate deaminase; solubilization of phosphate and potassium; and nitrogen metabolism. Similarly, genes involved in heavy metals (As, Co, Zn, Cu, Mn, Se, Cd, and Fe) tolerance were detected. These support its potential as a heavy metal-tolerant plant growth-promoting bacterium and a good genetic resource that can be employed to improve phytoremediation efficiency of heavy metal-contaminated soil via biotechnological techniques. This, to the best of our knowledge, is the first report on the complete genome sequence of heavy metal-tolerant plant growth-promoting E. tabaci.
    Matched MeSH terms: DNA, Bacterial
  4. Genetic diversity and DNA barcoding of the black fly (Diptera: Simuliidae) vectors of parasites causing human onchocerciasis in Guatemala
    Pramual P, Bunchom N, Saijuntha W, Tada I, Suganuma N, Agatsuma T
    Trop Biomed, 2019 Dec 01;36(4):938-957.
    PMID: 33597465
    Genetic variation based on mitochondrial cytochrome c oxidase I (COI) and II (COII) sequences was investigated for three black fly nominal species, Simulium metallicum Bellardi complex, S. callidum Dyar and Shannon, and S. ochraceum Walker complex, which are vectors of human onchocerciasis from Guatemala. High levels of genetic diversity were found in S. metallicum complex and S. ochraceum complex with maximum intraspecific genetic divergences of 11.39% and 4.25%, respectively. Levels of genetic diversity of these nominal species are consistent with species status for both of them as they are cytologically complexes of species. Phylogenetic analyses revealed that the S. metallicum complex from Guatemala divided into three distinct clades, two with members of this species from several Central and South American countries and another exclusively from Mexico. The Simulium ochraceum complex from Guatemala formed a clade with members of this species from Mexico and Costa Rica while those from Ecuador and Colombia formed another distinct clade. Very low diversity in S. callidum was found for both genes with maximum intraspecific genetic divergence of 0.68% for COI and 0.88% for COII. Low genetic diversity in S. callidum might be a consequence of the result being informative of only recent population history of the species.
    Matched MeSH terms: DNA Barcoding, Taxonomic
  5. Fulltext Antarctic bacteria inhibit the growth of pathogens
    Wong, C.M.V.L., Chung, H.H., Aisyah, S., Omar, S., Cheah, Y.K., Maria de, L.G., et al.
    ASM Science Journal, 2009;3(2):107-112.
    MyJurnal
    There are relatively little data on bacteria with antimicrobial activities from Antarctic, especially from the South Shetland Islands when compared to the other parts of the world. Hence, this project was set to isolate and characterize bacteria that produce anti-microbial compounds from Greenwich Island (one of the South Shetland Islands), Antarctica. A total of 356 strains of bacteria were isolated from Greenwich Island. They were screened for antimicrobial activities against 13 Gram-negative and one Gram-positive indicator food-borne pathogens. Two out of the 356 Antarctic bacterial strains exhibited an antagonistic effect on the indicator strains, Escherichia coli, Salmonella spp., Klebsiella pneumoniae, Enterobacter cloacae, Vibrio parahaemolyticus and Bacillus cereus. The two Antarctic bacterial strains were designated as SS157 and SR13. Biochemical and 16S rDNA analysis indicated that the strain SS157 was closely related to Pseudomonas congelans while the strain SR13 was closely related to Pseudomonas tremae. The anti-microbial compounds produced by the two Antarctic bacteria were not sensitive to temperature and were not degraded by trypsin or pronase indicating that they were likely to be chemical compounds or antibiotics. Antimicrobial compounds from strains SS157 and SR13 were broad spectrum, and targeted both Gram-positive and negative pathogens.
    Matched MeSH terms: DNA, Ribosomal
  6. Fulltext The role of blood transfusion in HCV infection: a study testing Ab: RNA & genotype
    Al-Kubaisy, Waqar A., Niazi, Amjad D.
    Int J Public Health Res, 2011;1(2):72-78.
    MyJurnal
    Introduction Hepatitis C Virus (HCV) recently was identified as a major cause of post transfusion hepatitis world wide. To evaluate the role of blood transfusion on the prevalence of HCV infection, by testing antibody and RNA as well as the genotypes of HCV .Also to detect if Blood transfusion acts as unconfounding risk factor for HCV infection.
    Methods Sera from 3491 pregnant women were investigated for the presence of HCV antibodies (anti-HCV) by using third generation enzyme immunoassay (EIA-3) as screening test, followed by immunoblot assay (Lia Tek-III). In addition 94 sera of studied women were subjected to molecular analysis (at laboratories of Sorin BioMedica - Italy) for the detection of viral RNA and genotypes of HCV. Using RT-PCR & DNA Enzyme immunoassay (DEIA) method.
    Results Our study revealed, that seroprevalence rate of HCV specific Ab & RNA were significantly higher (16.32 %, 80% respectively) among women with a history of blood transfusion, compared to those (2.53%, 56.5%) with no such history P=0.0001, P=0.01. And there is a significant direct linear correlation between number of blood transfused and the seropositive rate of anti-HCV (r=0.7, p=0.046). Based on multivariate analysis, interestingly, this study confirmed that, blood transfusion significantly acting as unconfounding risk factor for acquiring HCV infection (Adjusted OR=1.938,95% C.I=1.646-2.28). And the risk of exposure is increases with increased number of blood transfused. Although, we found no significant association between, HCV genotypic distribution and history of blood transfusion. However, high proportion of women with a history of blood transfusion were harboring HCV genotype -4 or 1b, 50%,40%, resepctively.
    Conclusions Our study shows, evidence that, blood transfusion acts as unconfounding risk factor for acquiring and in a mode of transmission of HCV infection. Therefore strict screening of blood donor for HCV-Abs and / or RNA is highly recommended.
    Matched MeSH terms: DNA
  7. Fulltext HPV positivity and its' influencing factors among invasive cervical cancer women in Malaysia
    Sharifa Ezat Wan Puteh, Norin Rahayu Samsuddin, Sharifah Noor Akmal Syed Hussain, Shamsul Azhar Shah, Syed Mohamed Aljunid
    Int J Public Health Res, 2011;1(1):13-22.
    MyJurnal
    Accepted 10 August 2011.
    Introduction Cervical cancer (CC) is the second most prevalent female cancer in Malaysia. Almost 70% of its’ causal factors are attributable to oncogenic human papillomavirus (HPV) types 16, 18 and other risk factors. HPV genotypes distributions are also noted to differ by geographical area.
    Methods This was cross sectional study conducted in 2007, to determine the influencing factors of HPV positivity and prevalence of HPV infections among patients with cervical cancer in Universiti Kebangsaan Malaysia Medical Centre (UKMMC). Patients’ paraffin-embedded cervical tissues kept in the Pathology Department from 1999 to 2007 were randomly selected. A total of 81 medical records with complete information were chosen as samples and patients were contacted for consent. Tissue samples were further derived for PCR DNA for HPV genotyping. Analyses included descriptive statistics; bivariate χ2 test and correlation were used to determine relationship between factors and HPV positivity. Significance level of less than 0.05 was taken as statistically significant.
    Results Mean age of cancer diagnosis was at 52 ± 12.2 years. Women of Chinese ethnicity was the highest ethnicity to be HPV positive at 65.4% and squamous cell carcinoma was more commonly found (59.3%) compared with other types of cancers. The prevalence of HPV positivity was 92.6% with type 16 being the most common (74.1%), followed by type 33 (30.9%) and 18 (22.2%). Multiple HPV infections were a common finding at 54.3%. Factors thought to influence positivity i.e. age of intercourse, number of sexual partners, number of parity, smoking status of patients and their partners, oral contraceptive usage, presence of chronic illnesses and cancer stage were not significantly associated with HPV positivity. Increased CC severity level was not associated with increased number of HPV infections (Pearson correlation 0.58; p =0.607).
    Conclusions High HPV positivity at 92.6% was found among ICC patients. Factors thought to influence HPV positivity were not significant. The top three HPV genotypes were type 16 followed by type 33 and 18. However, local women HPV serotypes findings need to be replicated in a larger population sample.
    Matched MeSH terms: DNA
  8. Rapid detection of α-thalassaemia variants using droplet digital PCR
    Lee TY, Lai MI, Ramachandran V, Tan JA, Teh LK, Othman R, et al.
    Int J Lab Hematol, 2016 Aug;38(4):435-43.
    PMID: 27349818 DOI: 10.1111/ijlh.12520
    INTRODUCTION: Alpha thalassaemia is a highly prevalent disease globally and is a well-known public health problem in Malaysia. The deletional forms of the mutation are the most common forms found in alpha thalassaemia. The three most common deletional alpha thalassaemia found in this region include --(SEA) deletion, -α(3.7) rightward and -α(4.2) leftward deletions. The prevalence rate of triplication alpha cases such as ααα(anti3.7) and ααα(anti4.2) is not known in Malaysia although it plays a role in exacerbating the clinical phenotypes in beta thalassaemia carriers. Recently, there have been more reported cases of rare alpha thalassaemia mutations due to the advancement of molecular techniques involved in thalassaemia detections. Therefore, it is essential to develop a new method which allows the detection of different alpha thalassaemia mutations including the rare ones simultaneously and accurately.

    METHODS: The purpose of this study was to design an assay for the detection of triplications, common and rare deletional alpha thalassaemia using droplet digital PCR (ddPCR).

    RESULTS: This is a quantitative detection method to measure the changes of copy number which can detect deletions, duplications and triplications of the alpha globin gene simultaneously.

    CONCLUSION: In conclusion, ddPCR is an alternative method for rapid detection of alpha thalassaemia variants in Malaysia.

    Matched MeSH terms: DNA Copy Number Variations
  9. Fulltext Antibiotic resistance and plasmid profile of Escherichia coli isolated from ducks in Penang, Malaysia
    Adzitey F., Ali, G.R.R., Huda, N., Ting, S.L.
    International Food Research Journal, 2013;20(3):1473-1478.
    MyJurnal
    Fifty five (n=55) isolates of Escherichia coli isolated from ducks in Penang, Malaysia were examined for their susceptibility to eleven different antibiotics and assayed for the presence of plasmid DNAs. All the 55 Escherichia coli isolates were resistant (100%) to vancomycin. Higher resistance (= 60) occurred for tetracycline 51 (92.7%), ampicillin 40 (72.7%), streptomycin 37 (67.3%), and sulfamethoxazole-trimethophrim 37 (67.3%). No and low resistance was observed for nitrofurantoin (0%) and gentamicin (1.8%), respectively. The isolates also showed some intermediate resistances to all antibiotics examined except for vancomycin. The 55 Escherichia coli isolates exhibited 23 different antibiotic resistant patterns with MAR index ranging from 0.09-0.82. Majority of the Escherichia coli isolates exhibited resistant pattern of VA-C-OFX-SXT-TE-AMP-NA-KF and VA-S-C-OFX-SXT-TE-AMP-NA-KF with MAR index of 0.73 and 0.82, respectively. The smallest plasmid DNA size was 1.2 kb and the largest plasmid DNA size was 81.5 kb. 51 (93%) of the duck Escherichia coli isolates harbored plasmids. The was no direct correlation between plasmid DNA sizes and antibiotic resistant among the duck Escherichia coli isolates. Thus, the antibiotic resistant of the Escherichia coli isolates could mostly be mediated by chromosomes instead of plasmids. This study also suggests that the use of antibiotics in duck farming in Penang, Malaysia needs to be controlled to prevent the spread of multiple antibiotic resistant Escherichia coli isolates.
    Matched MeSH terms: DNA
  10. Fulltext Technology advancement enabling the link of gut microbiota with obesity and metabolic disorder
    Hartini Yusof, Mohamad Shafiq Aazmi, Teh Lay Kek, Mohd Zaki Salleh, Ili Ng Abdullah, Aminuddin Ahmad, et al.
    Jurnal Sains Kesihatan Malaysia, 2015;13(1):77-91.
    MyJurnal
    Obesity is a growing epidemic due to an accelerated phase of industrialization and urbanization with the overfed people
    now outnumbered the underfed. It is the major public health problem with a lot of research interest as it is associated
    with many complicated chronic disorders such as type-2 diabetes, cardiovascular diseases (CVD) and cancers. A global
    estimation of 2.8 million deaths per year is due to obesity and there are tremendous on-going efforts to identify hosts
    and environmental factors that infl uence the cause and pathogenesis of obesity. Concerted efforts from different research
    groups had successfully shown that obese subjects have altered composition of gut microbiota and transplantation of this
    microbiota infl uences body weight in the germ-free recipient mice. The advancement of technology had made possible
    the study of gut microbiota which was unculturable for better understanding of their impact to human health. Rapid
    deep sequencing of DNA at reasonable cost through various options of platforms followed by data analysis using robust
    bioinformatic tools are an important way of analysing the gut microbiome. Here we review the role of gut microbiota
    which modulates host’s metabolic functions and gene expression, facilitating the extraction and storage of energy from the
    ingested dietary substances and leading to body-weight gain. We will discuss on the different techniques used, focusing
    on the high-defi nition technologies for the determination of the composition, function and ecology of gut microbiota. This
    allows the appropriate selection of platform which becomes the key for success of subsequent research.
    Matched MeSH terms: DNA
  11. Fulltext Visual impairment and its associated factors among the adult population of Kuala Pajam village, Branang, Selangor, Malaysia
    Rozhan, S.M.R., Halim, I., Shamsul Azhar Sha
    Malaysian Journal of Community Health, 2009;15(2):1-8.
    MyJurnal
    Background : Visual impairment among the rural community has rarely been studied in this country. The purpose of this study is to determine the prevalence of visual impairment and its related factors among the adult population of Kampung Kuala Pajam, Branang.
    Methodology : A cross sectional study was carried out in Kampung Kuala Pajam, Mukim Beranang from 25th of December till 30th of December 2007. Universal sampling is adopted and the sample size consists of 321 respondents who is 18 years and above. Trained interviewer has been used to obtain the data through questionnaire and eye examinations using logMAR chart, Red Reflex eye test, Relative Afferent Pupillary Defect (RAPD) test and Pin-Hole test.
    Result : A total of 261 respondents who fulfil the criteria were interviewed and had eyes examination during the study period. The prevalence of visual impairment in this population was 9.2% and factors that showed significant association were age (p
    Matched MeSH terms: Random Amplified Polymorphic DNA Technique
  12. Fulltext Feral Cat Globetrotters: genetic traces of historical human-mediated dispersal
    Koch K, Algar D, Schwenk K
    Ecol Evol, 2016 08;6(15):5321-32.
    PMID: 27551385 DOI: 10.1002/ece3.2261
    Endemic species on islands are highly susceptible to local extinction, in particular if they are exposed to invasive species. Invasive predators, such as feral cats, have been introduced to islands around the world, causing major losses in local biodiversity. In order to control and manage invasive species successfully, information about source populations and level of gene flow is essential. Here, we investigate the origin of feral cats of Hawaiian and Australian islands to verify their European ancestry and a potential pattern of isolation by distance. We analyzed the genetic structure and diversity of feral cats from eleven islands as well as samples from Malaysia and Europe using mitochondrial DNA (ND5 and ND6 regions) and microsatellite DNA data. Our results suggest an overall European origin of Hawaiian cats with no pattern of isolation by distance between Australian, Malaysian, and Hawaiian populations. Instead, we found low levels of genetic differentiation between samples from Tasman Island, Lana'i, Kaho'olawe, Cocos (Keeling) Island, and Asia. As these populations are separated by up to 10,000 kilometers, we assume an extensive passive dispersal event along global maritime trade routes in the beginning of the 19th century, connecting Australian, Asian, and Hawaiian islands. Thus, islands populations, which are characterized by low levels of current gene flow, represent valuable sources of information on historical, human-mediated global dispersal patterns of feral cats.
    Matched MeSH terms: DNA, Mitochondrial
  13. Fulltext Genome wide profiling in oral squamous cell carcinoma identifies a four genetic marker signature of prognostic significance
    Vincent-Chong VK, Salahshourifar I, Woo KM, Anwar A, Razali R, Gudimella R, et al.
    PLoS One, 2017;12(4):e0174865.
    PMID: 28384287 DOI: 10.1371/journal.pone.0174865
    BACKGROUND: Cancers of the oral cavity are primarily oral squamous cell carcinomas (OSCCs). Many of the OSCCs present at late stages with an exceptionally poor prognosis. A probable limitation in management of patients with OSCC lies in the insufficient knowledge pertaining to the linkage between copy number alterations in OSCC and oral tumourigenesis thereby resulting in an inability to deliver targeted therapy.

    OBJECTIVES: The current study aimed to identify copy number alterations (CNAs) in OSCC using array comparative genomic hybridization (array CGH) and to correlate the CNAs with clinico-pathologic parameters and clinical outcomes.

    MATERIALS AND METHODS: Using array CGH, genome-wide profiling was performed on 75 OSCCs. Selected genes that were harboured in the frequently amplified and deleted regions were validated using quantitative polymerase chain reaction (qPCR). Thereafter, pathway and network functional analysis were carried out using Ingenuity Pathway Analysis (IPA) software.

    RESULTS: Multiple chromosomal regions including 3q, 5p, 7p, 8q, 9p, 10p, 11q were frequently amplified, while 3p and 8p chromosomal regions were frequently deleted. These findings were in confirmation with our previous study using ultra-dense array CGH. In addition, amplification of 8q, 11q, 7p and 9p and deletion of 8p chromosomal regions showed a significant correlation with clinico-pathologic parameters such as the size of the tumour, metastatic lymph nodes and pathological staging. Co-amplification of 7p, 8q, 9p and 11q regions that harbored amplified genes namely CCND1, EGFR, TPM2 and LRP12 respectively, when combined, continues to be an independent prognostic factor in OSCC.

    CONCLUSION: Amplification of 3q, 5p, 7p, 8q, 9p, 10p, 11q and deletion of 3p and 8p chromosomal regions were recurrent among OSCC patients. Co-alteration of 7p, 8q, 9p and 11q was found to be associated with clinico-pathologic parameters and poor survival. These regions contain genes that play critical roles in tumourigenesis pathways.

    Matched MeSH terms: DNA Copy Number Variations
  14. Fulltext Little White Lies: Pericarp Color Provides Insights into the Origins and Evolution of Southeast Asian Weedy Rice
    Cui Y, Song BK, Li LF, Li YL, Huang Z, Caicedo AL, et al.
    G3 (Bethesda), 2016 Dec 07;6(12):4105-4114.
    PMID: 27729434 DOI: 10.1534/g3.116.035881
    Weedy rice is a conspecific form of cultivated rice (Oryza sativa L.) that infests rice fields and results in severe crop losses. Weed strains in different world regions appear to have originated multiple times from different domesticated and/or wild rice progenitors. In the case of Malaysian weedy rice, a multiple-origin model has been proposed based on neutral markers and analyses of domestication genes for hull color and seed shattering. Here, we examined variation in pericarp (bran) color and its molecular basis to address how this trait evolved in Malaysian weeds and its possible role in weed adaptation. Functional alleles of the Rc gene confer proanthocyanidin pigmentation of the pericarp, a trait found in most wild and weedy Oryzas and associated with seed dormancy; nonfunctional rc alleles were strongly favored during rice domestication, and most cultivated varieties have nonpigmented pericarps. Phenotypic characterizations of 52 Malaysian weeds revealed that most strains are characterized by the pigmented pericarp; however, some weeds have white pericarps, suggesting close relationships to cultivated rice. Phylogenetic analyses indicate that the Rc haplotypes present in Malaysian weeds likely have at least three distinct origins: wild O. rufipogon, white-pericarp cultivated rice, and red-pericarp cultivated rice. These diverse origins contribute to high Rc nucleotide diversity in the Malaysian weeds. Comparison of Rc allelic distributions with other rice domestication genes suggests that functional Rc alleles may confer particular fitness benefits in weedy rice populations, for example, by conferring seed dormancy. This may promote functional Rc introgression from local wild Oryza populations.
    Matched MeSH terms: Sequence Analysis, DNA
  15. Fulltext Identification of Predictive DNA Methylation Biomarkers for Chemotherapy Response in Colorectal Cancer
    Baharudin R, Ab Mutalib NS, Othman SN, Sagap I, Rose IM, Mohd Mokhtar N, et al.
    Front Pharmacol, 2017;8:47.
    PMID: 28243201 DOI: 10.3389/fphar.2017.00047
    Resistance to 5-Fluorouracil (5-FU) is a major obstacle to the successful treatment of colorectal cancer (CRC) and posed an increased risk of recurrence. DNA methylation has been suggested as one of the underlying mechanisms for recurrent disease and its contribution to the development of drug resistance remains to be clarified. This study aimed to determine the methylation phenotype in CRC for identification of predictive markers for chemotherapy response. We performed DNA methylation profiling on 43 non-recurrent and five recurrent CRC patients using the Illumina Infinium HumanMethylation450 Beadchip assay. In addition, CRC cells with different genetic backgrounds, response to 5-FU and global methylation levels (HT29 and SW48) were treated with 5-FU and DNA methylation inhibitor 5-aza-2'-deoxycytidine (5-azadC). The singular and combined effects of these two drug classes on cell viability and global methylation profiles were investigated. Our genome-wide methylation study on the clinical specimens showed that recurrent CRCs exhibited higher methylation levels compared to non-recurrent CRCs. We identified 4787 significantly differentially methylated genes (P < 0.05); 3112 genes were hyper- while 1675 genes were hypomethylated in the recurrent group compared to the non-recurrent. Fifty eight and 47 of the significantly hypermethylated and hypomethylated genes have an absolute recurrent/non-recurrent methylation difference of ≥20%. Most of the hypermethylated genes were involved in the MAPK signaling pathway which is a key regulator for apoptosis while the hypomethylated genes were involved in the PI3K-AKT signaling pathway and proliferation process. We also demonstrate that 5-azadC treatment enhanced response to 5-FU which resulted in significant growth inhibition compared to 5-FU alone in hypermethylated cell lines SW48. In conclusion, we found the evidence of five potentially biologically important genes in recurrent CRCs that could possibly serve as a new potential therapeutic targets for patients with chemoresistance. We postulate that aberrant methylation of CCNEI, CCNDBP1, PON3, DDX43, and CHL1 in CRC might be associated with the recurrence of CRC and 5-azadC-mediated restoration of 5-FU sensitivity is mediated at least in part by MAPK signaling pathway.
    Matched MeSH terms: DNA Methylation
  16. Fulltext Tiger on the prowl: Invasion history and spatio-temporal genetic structure of the Asian tiger mosquito Aedes albopictus (Skuse 1894) in the Indo-Pacific
    Maynard AJ, Ambrose L, Cooper RD, Chow WK, Davis JB, Muzari MO, et al.
    PLoS Negl Trop Dis, 2017 04;11(4):e0005546.
    PMID: 28410388 DOI: 10.1371/journal.pntd.0005546
    BACKGROUND: Within the last century, increases in human movement and globalization of trade have facilitated the establishment of several highly invasive mosquito species in new geographic locations with concurrent major environmental, economic and health consequences. The Asian tiger mosquito, Aedes albopictus, is an extremely invasive and aggressive daytime-biting mosquito that is a major public health threat throughout its expanding range.

    METHODOLOGY/PRINCIPAL FINDINGS: We used 13 nuclear microsatellite loci (on 911 individuals) and mitochondrial COI sequences to gain a better understanding of the historical and contemporary movements of Ae. albopictus in the Indo-Pacific region and to characterize its population structure. Approximate Bayesian computation (ABC) was employed to test competing historical routes of invasion of Ae. albopictus within the Southeast (SE) Asian/Australasian region. Our ABC results show that Ae. albopictus was most likely introduced to New Guinea via mainland Southeast Asia, before colonizing the Solomon Islands via either Papua New Guinea or SE Asia. The analysis also supported that the recent incursion into northern Australia's Torres Strait Islands was seeded chiefly from Indonesia. For the first time documented in this invasive species, we provide evidence of a recently colonized population (the Torres Strait Islands) that has undergone rapid temporal changes in its genetic makeup, which could be the result of genetic drift or represent a secondary invasion from an unknown source.

    CONCLUSIONS/SIGNIFICANCE: There appears to be high spatial genetic structure and high gene flow between some geographically distant populations. The species' genetic structure in the region tends to favour a dispersal pattern driven mostly by human movements. Importantly, this study provides a more widespread sampling distribution of the species' native range, revealing more spatial population structure than previously shown. Additionally, we present the most probable invasion history of this species in the Australasian region using ABC analysis.

    Matched MeSH terms: Sequence Analysis, DNA
  17. Fulltext Biodynamics of hepatitis C virus in haemodialysis patients in Pahang
    Mohammed Saad, A.M., Mohammed Imad, A.M., Aini, H.H., Seman, M.R.
    International Medical Journal Malaysia, 2012;11(1):23-30.
    MyJurnal
    Introduction: HCV infection is frequent in patients undergoing maintenance haemodialysis, with prevalence between 8 and 10%. Hepatitis C has an adverse effect on both patient and graft survival in those who get renal transplants. There are relatively scarce reports on the natural fluctuation in viral load level in patients on chronic haemodialysis. Materials and Methods: This is a longitudinal short-term three months study, where 27 chronic haemodialysis patients infected with known HCV genotypes were recruited from seven haemodialysis centres in Pahang. Serum samples were collected monthly, both pre- and post-haemodialysis sessions, over a period of three months. Viral RNA was extracted from serum using QIAamp Viral RNA Extraction kit (Qiagen). The HCV viral load was measured using one-step reverse transcriptase qPCR (Applied Biosystems) targeting the 5`HCV non-coding region (5’UTR). The serum α-IFN level was measured using commercial ELISA kit (Amersham, UK). Six biochemical liver function tests (AST, ALP, TP, albumin, ALT and TB) were also done for all pre-haemodialysis samples. Results: All patients showed persistent low level viral load that varied significantly over the study period (p = 0.001). HCV genotype 1 viral load was significantly higher than that of genotype 3. Conclusion: No apparent correlation could be recognized between the viral loads and the corresponding interferon-alpha levels which were detectable in only a few patients during the period of study.
    Matched MeSH terms: RNA-Directed DNA Polymerase
  18. Fulltext Aloe emodin enhances tamoxifen cytotoxicity effect on ER a-positive breast cancer cells, MCF-7, through downregulation of MEK1 and MEK2
    Amin, I.M., Sheikh Abdul Kadir, S.H., Isa, M.R., Rosdy. N.M.M.N.M., Hasani NAH
    JUMMEC, 2016;19(1):1-10.
    MyJurnal
    The positive response to tamoxifen in ERa-positive breast cancer patients is usually of a short duration as many
    of the patients eventually develop resistance. Our preliminary results show that aloe emodin extracted from
    the leaves of the Aloe barbadensis Miller demonstrated a cytotoxicity that is selective to ERa-positive breast
    cancer cells (MCF-7), but not to ERa-negative breast cancer cells (MDA-MB-231) and to the control cells (MCF-
    10A). The objective of this study was to test the hypothesis that aloe emodin may enhance the response of
    MCF-7 cells to treatment with tamoxifen. MCF-7 cells were treated with aloe emodin alone, tamoxifen alone
    or a combination of emodin and tamoxifen, at their respective IC50 concentrations and at different time points
    of 24 hours, 48 hours and 72 hours. The respective IC50s were the concentrations of aloe emodin and tamoxifen
    required to achieve 50% inhibition of the cells in the study. Cell viability and apoptosis were determined using
    trypan blue exclusion and DNA fragmentation assays, respectively. The involvement of RAS/MEKs/ERKs genes
    of MAPK signalling pathways with aloe emodin was determined using QuantiGene 2.0 Plex assay. Data was
    evaluated using the one-way ANOVA test. Our findings showed that aloe emodin enhanced the cytotoxicity of
    tamoxifen on MCF-7 cells through apoptosis by downregulation of MEK1/2 genes. Our research may provide a
    rational basis for further in vivo studies to verify the efficacy of a combination of aloe emodin and tamoxifen
    on the viability of ERa-positive-breast cancer cells.
    Matched MeSH terms: DNA Fragmentation
  19. Studies of the chemical composition of a healing skin wound in rats, and of the concentrations of some constituents of tissues distant from the healing wound
    Candlish J, Chandra N
    Biochem. J., 1967 Mar;102(3):767-73.
    PMID: 16742493
    1. A skin lesion was made in rats by dorsal incision and the insertion of a polythene tube. 2. Over a period of 25 days after wounding, assays were performed for ascorbic acid, DNA, hydroxyproline, methionine, tryptophan, tyrosine and free amino acids in the lesion tissue. 3. The neutral-salt-soluble proteins of the lesion tissue were fractionated on DEAE-Sephadex, with the separation of fibrinogen and gamma-globulin from a serum protein fraction. 4. Over a period of 20 days after wounding, in wounded rats and in controls, assays were conducted for: ascorbic acid in lens and liver, hydroxyproline, soluble protein, methionine and water in muscle and tendon, and free amino acids in muscle. 5. Relative to controls there was a decrease in lens and liver ascorbic acid, a rise in tendon hydroxyproline, a rise in muscle free amino acids, a fall in muscle protein and a rise in tendon and muscle water.
    Matched MeSH terms: DNA
  20. Fulltext Prevalence of rsaI polymorphism in the 5’ untranslated region (UTR) of pro-opiomelanocortin (POMC) gene and its sssociation with obesity in the Kampar Health Clinic Cohort, Malaysia
    Lee, H.M., Fan, S.H., Say, Y.H.
    Malaysian Journal of Medicine and Health Sciences, 2012;8(1):61-68.
    MyJurnal
    The pandemic of obesity is of great concern as its associated co-morbidities are devastating; causing lifelong burden to individual’s health and is economically costly to a country. Factors that lead to obesity are a combination of environmental and genetic factors. The Pro-opiomelanocortin (POMC) gene resides in chromosome 2p23.3, and its protein is composed of 241 amino acids which is responsible for the production of polyhormones that regulate appetite and food intake. The study aimed to investigate the prevalence of the RsaI single nucleotide polymorphism (SNP) site in the 5’-untranslated region (UTR) of POMC and its possible association with obesity among 302 multi-ethnic Malaysian subjects (142 obese, 160 non-obese; 120 males, 182 females) from the Kampar Health Clinic. Subjects were recruited by convenience sampling with informed consent and socio-demographic data as well as anthropometric measurements were taken. Subjects were genotyped by polymerase chain reaction - restriction fragment length polymorphism (PCR-RFLP) analysis using DNA extracted from blood. The distribution of the RsaI genotypes was significantly different among the different ethnicities, but the mutated RsaI (- / -) genotype was rare as it only occurred in 8.9% of the subjects. With the frequency of the RsaI (-) allele of 0.31, it was associated with the percentage of skeletal muscles (p
    Matched MeSH terms: DNA
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