Displaying publications 161 - 180 of 863 in total

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  1. Danderson CA, Downie SR, Hermann M
    Mol Phylogenet Evol, 2018 01;118:286-305.
    PMID: 29017853 DOI: 10.1016/j.ympev.2017.10.006
    The Arracacia clade (Apiaceae, Apioideae) is a heterogeneous assemblage of 12 genera, comprising 111 known species distributed in high montane temperate and sub-alpine habitats of meso- and South America. Previous studies have indicated that the genera Arracacia, Coulterophytum, and Prionosciadium are polyphyletic, but for the most part relationships among the members of the clade are largely unknown. Initially, cladistic analyses of nrDNA ITS sequences were carried out on 212 accessions (122 taxa), representing 92 species of the Arracacia clade and outgroups from the closely-related páramo genera Cotopaxia, Niphogeton, and Perissocoeleum and members of the Perennial Endemic North American clade and its allies. Using the ITS results to inform sampling of a small subset of taxa, a pilot study examining the phylogenetic utility of 20 noncoding chloroplast loci was subsequently performed to identify those regions most useful at resolving relationships. A cost-benefit analysis determined that five loci (trnQ-5'rps16, trnD-trnT, rpl32-trnL, psbD-trnT, ndhA intron) would maximize resolution and branch support in the clade. Cladistic analyses of four of these loci (trnQ-5'rps16, trnD-trnT, rpl32-trnL, ndhA intron) and the ITS region, separately and combined, revealed that Arracacia, Coaxana, Coulterophytum, Prionosciadium, and Rhodosciadium are each polyphyletic and that Donnellsmithia and Myrrhidendron are each monophyletic. Although most relationships in the Arracacia clade and among the closely-related genera Cotopaxia, Niphogeton, and Perissocoeleum are poorly resolved and supported, ten groups are recognized for future revisionary studies. Polyploidy and rapid species radiation have likely confounded generic circumscriptions and interpretation of relationships.
    Matched MeSH terms: Sequence Analysis, DNA
  2. Gan HM, Tan MH, Lee YP, Schultz MB, Horwitz P, Burnham Q, et al.
    Mol Phylogenet Evol, 2018 01;118:88-98.
    PMID: 28966124 DOI: 10.1016/j.ympev.2017.09.022
    To further understand the evolutionary history and mitogenomic features of Australia's highly distinctive freshwater crayfish fauna, we utilized a recently described rapid mitogenome sequencing pipeline to generate 24 new crayfish mitogenomes including a diversity of burrowing crayfish species and the first for Astacopsis gouldi, the world's largest freshwater invertebrate. Whole mitogenome-based phylogeny estimates using both Bayesian and Maximum Likelihood methods substantially strengthen existing hypotheses for systematic relationships among Australian freshwater crayfish with evidence of pervasive diversifying selection and accelerated mitochondrial substitution rate among the members of the clade representing strongly burrowing crayfish that may reflect selection pressures for increased energy requirement for adaptation to terrestrial environment and a burrowing lifestyle. Further, gene rearrangements are prevalent in the burrowing crayfish mitogenomes involving both tRNA and protein coding genes. In addition, duplicated control regions were observed in two closely related Engaeus species, together with evidence for concerted evolution. This study significantly adds to the understanding of Australian freshwater crayfish evolutionary relationships and suggests a link between mitogenome evolution and adaptation to terrestrial environments and a burrowing lifestyle in freshwater crayfish.
    Matched MeSH terms: Sequence Analysis, DNA
  3. Mertens KN, Carbonell-Moore MC, Pospelova V, Head MJ, Highfield A, Schroeder D, et al.
    Harmful Algae, 2018 01;71:57-77.
    PMID: 29306397 DOI: 10.1016/j.hal.2017.12.003
    Strains of a dinoflagellate from the Salton Sea, previously identified as Protoceratium reticulatum and yessotoxin producing, have been reexamined morphologically and genetically and Pentaplacodinium saltonense n. gen. et sp. is erected to accommodate this species. Pentaplacodinium saltonense differs from Protoceratium reticulatum (Claparède et Lachmann 1859) Bütschli 1885 in the number of precingular plates (five vs. six), cingular displacement (two widths vs. one), and distinct cyst morphology. Incubation experiments (excystment and encystment) show that the resting cyst of Pentaplacodinium saltonense is morphologically most similar to the cyst-defined species Operculodinium israelianum (Rossignol, 1962) Wall (1967) and O. psilatum Wall (1967). Collections of comparative material from around the globe (including Protoceratium reticulatum and the genus Ceratocorys) and single cell PCR were used to clarify molecular phylogenies. Variable regions in the LSU (three new sequences), SSU (12 new sequences) and intergenic ITS 1-2 (14 new sequences) were obtained. These show that Pentaplacodinium saltonense and Protoceratium reticulatum form two distinct clades. Pentaplacodinium saltonense forms a monophyletic clade with several unidentified strains from Malaysia. LSU and SSU rDNA sequences of three species of Ceratocorys (C. armata, C. gourreti, C. horrida) from the Mediterranean and several other unidentified strains from Malaysia form a well-supported sister clade. The unique phylogenetic position of an unidentified strain from Hawaii is also documented and requires further examination. In addition, based on the V9 SSU topology (bootstrap values >80%), specimens from Elands Bay (South Africa), originally described as Gonyaulax grindleyi by Reinecke (1967), cluster with Protoceratium reticulatum. The known range of Pentaplacodinium saltonense is tropical to subtropical, and its cyst is recorded as a fossil in upper Cenozoic sediments. Protoceratium reticulatum and Pentaplacodinium saltonense seem to inhabit different niches: motile stages of these dinoflagellates have not been found in the same plankton sample.
    Matched MeSH terms: Sequence Analysis, DNA
  4. Loke MF, Chua EG, Gan HM, Thulasi K, Wanyiri JW, Thevambiga I, et al.
    PLoS One, 2018;13(12):e0208584.
    PMID: 30576312 DOI: 10.1371/journal.pone.0208584
    Colorectal cancer (CRC) is ranked the third most common cancer in human worldwide. However, the exact mechanisms of CRC are not well established. Furthermore, there may be differences between mechanisms of CRC in the Asian and in the Western populations. In the present study, we utilized a liquid chromatography-mass spectrometry (LC-MS) metabolomic approach supported by the 16S rRNA next-generation sequencing to investigate the functional and taxonomical differences between paired tumor and unaffected (normal) surgical biopsy tissues from 17 Malaysian patients. Metabolomic differences associated with steroid biosynthesis, terpenoid biosynthesis and bile metabolism could be attributed to microbiome differences between normal and tumor sites. The relative abundances of Anaerotruncus, Intestinimonas and Oscillibacter displayed significant relationships with both steroid biosynthesis and terpenoid and triterpenoid biosynthesis pathways. Metabolites involved in serotonergic synapse/ tryptophan metabolism (Serotonin and 5-Hydroxy-3-indoleacetic acid [5-HIAA]) were only detected in normal tissue samples. On the other hand, S-Adenosyl-L-homocysteine (SAH), a metabolite involves in methionine metabolism and methylation, was frequently increased in tumor relative to normal tissues. In conclusion, this study suggests that local microbiome dysbiosis may contribute to functional changes at the cancer sites. Results from the current study also contributed to the list of metabolites that are found to differ between normal and tumor sites in CRC and supported our quest for understanding the mechanisms of carcinogenesis.
    Matched MeSH terms: Sequence Analysis, DNA
  5. Ameerah Jaafar, Feizel Alsiddiq, Ling, King-Hwa
    MyJurnal
    Gene mutation is one of the etiologies of early-onset epileptic encephalopathy (EOEE), an age-dependent seizure in infants, which leads to brain defects. Previous studies have shown that several genes namely, aristalessrelated homeobox (ARX), cyclindependent kinaselike 5 (CDKL5) and syntaxinbinding protein 1 (STXBP1) are responsible for the pathophysiology of the syndrome. Thestudy involved 20 EOEE patients and 60 control subjects, which aimed toinvestigatethe clinical association of Malaysian EOEE subjects with 13 known pathogenic mutations in the genes of interest. In addition, the entire ARX exonic region was also sequenced for known and novel mutations. PCR specificity and efficiency were optimized using conventional PCR and High Resolution Melting Analysis (HRMA). All cases and approximately 10% of control amplicon samples were purified and subjected to DNA sequencing. All known mutations reported previously were not found in control subjects and Malaysian EOEE patients with 100% confirmation by sequencing results. Sequencing of ARX exonic regionsof patient samplesdid not find any mutation in all exons. The preliminary study indicates that selected known pathogenic mutations of ARX, CDKL5and STXBP1are not associated with EOEE in Malaysian paediatric patients.
    Matched MeSH terms: Sequence Analysis, DNA
  6. Haque E, Banik U, Monwar T, Anthony L, Adhikary AK
    PLoS One, 2018;13(3):e0194516.
    PMID: 29590206 DOI: 10.1371/journal.pone.0194516
    Human adenovirus type 3 (HAdV-3) respiratory infections occurs worldwide in both children and adults, leading to severe morbidity and mortality, particularly in the paediatric age group and especially in neonates. During HAdV infection, neutralizing antibodies are formed against the epitopes located in the hyper variable regions (HVRs) of the hexon protein. These neutralizing antibodies provide protection against reinfection by viruses of the same type. Therefore it is reasonable to speculate that variations of HAdV-3 in the HVRs could impair the immunity acquired by previous infection with a different strain with variation in its HVRs. HAdV-3 has recently become the major agent of acute respiratory infection worldwide, being responsible for 15% to 87% of all adenoviral respiratory infections. However, despite the increased prevalence of HAdV-3 as respiratory pathogen, the diversity of hexon proteins in circulating strains remains unexplored. This study was designed to explore the variation in HVRs of hexon among globally distributed strains of HAdV-3 as well as to discover possible relationship among them, thus possibly shedding light on the cause for the increased prevalence of HAdV-3. In this study, for the first time we analysed the hexon proteins of all 248 available strains of HAdV-3 from the NCBI database and compared them with those of the HAdV-3 prototype (GB stain). We found that the HVRs of HAdV-3 strains circulating worldwide were highly heterogeneous and have been mutating continuously since -their original isolation. Based on their immense heterogeneity, the strains can be categorized into 25 hexon variants (3Hv-1 to 3Hv-25), 4 of which (3Hv-1 to 3Hv-4) comprises 80% of the strains. This heterogeneity may explain why HAdV-3 has become the most prevalent HAdVs type worldwide. The heterogeneity of hexon proteins also shows that the development of a vaccine against HAdV-3 might be challenging. The data on hexon variants provided here may be useful for the future epidemiological study of HAdV-3 infection.
    Matched MeSH terms: Sequence Analysis, DNA
  7. Kistenich S, Rikkinen JK, Thüs H, Vairappan CS, Wolseley PA, Timdal E
    MycoKeys, 2018.
    PMID: 30294209 DOI: 10.3897/mycokeys.40.26025
    Krogiaborneensis Kistenich & Timdal, K.isidiata Kistenich & Timdal and K.macrophylla Kistenich & Timdal are described as new species, the first from Borneo and the two latter from New Caledonia. The new species are supported by morphology, secondary chemistry and DNA sequence data. Krogiaborneensis and K.isidiata contain sekikaic and homosekikaic acid, both compounds reported here for the first time from the genus. Krogiamacrophylla contains an unknown compound apparently related to boninic acid as the major compound. DNA sequences (mtSSU and nrITS) are provided for the first time for Krogia and a phylogeny of the genus based on 15 accessions of five of the six accepted species is presented. Krogiaantillarum is reported as new to Brazil, Guatemala and Mexico.
    Matched MeSH terms: Sequence Analysis, DNA
  8. Zam Zureena Mohd Rani, Nor Azian Abdul Murad, Saberi Saimun, Sri Noraima Othman, Rahman Jamal, Sue-Mian Then, et al.
    Neurology Asia, 2018;23(2):137-144.
    MyJurnal
    Background: The HLA-B*15:02 polymorphism in epileptic patients is known to be associated with carbamazepine-induced Stevens-Johnson syndrome (SJS). The prevalence of HLA-B*15:02 polymorphism seemed to be ethnic-specific with a higher frequency of HLA-B*15:02 in Asian compared to the Europeans. This study was performed to determine the frequency of the HLA-B*15:02 polymorphism in epileptic patients at the Chancellor Tuanku Muhriz Hospital-UKM Medical Centre (HCTM-UKMMC) using high resolution melting-real time PCR (HRM-QPCR) method.
    Methods: We performed a fast and effective in-house high resolution melting-real time polymerase chain reaction method and compared it with the conventional multiplex-PCR method. The specificity and sensitivity of each test were also determined using DNA from saliva.
    Results: Using the conventional multiplexPCR approach for screening, 25 out of 64 (39.1%) epileptic patients were positive for HLA-B*15:02. However, using the HRM-QPCR technique, 24/64 (37.5%) of the patients were positive. The one patient who tested positive by the multiplex-PCR but negative using the HRM-QPCR turned out to be negative by DNA sequencing. The HRM-QPCR and DNA sequencing showed 100% sensitivity and specificity. The multiplex-PCR showed 100% sensitivity and 98.4% specificity compared to both HRM-QPCR and DNA sequencing. The HRM-QPCR is also more cost-effective (DNA sequencing
    Matched MeSH terms: Sequence Analysis, DNA
  9. Zahari M, Sulaiman SA, Othman Z, Ayob Y, Karim FA, Jamal R
    Mediterr J Hematol Infect Dis, 2018;10(1):e2018056.
    PMID: 30210749 DOI: 10.4084/MJHID.2018.056
    Background: Haemophilia A (HA) and Haemophilia B (HB) are X-linked blood disorders that are caused by various mutations in the factor VIII (F8) and factor IX (F9) genes respectively. Identification of mutations is essential as some of the mutations are associated with the development of inhibitors. This study is the first comprehensive study of the F8 mutational profile in Malaysia.

    Materials and methods: We analysed 100 unrelated HA and 15 unrelated HB patients for genetic alterations in the F8 and F9 genes by using the long-range PCR, DNA sequencing, and the multiplex-ligation-dependent probe amplification assays. The prediction software was used to confirm the effects of these mutations on factor VIII and IX proteins.

    Results: 44 (53%) of the severe HA patients were positive for F8 intron 22 inversion, and three (3.6%) were positive for intron one inversion. There were 22 novel mutations in F8, including missense (8), frameshift (9), splice site (3), large deletion (1) and nonsense (1) mutations. In HB patients, four novel mutations were identified including the splice site (1), small deletion (1), large deletion (1) and missense (1) mutation.

    Discussion: The mutational spectrum of F8 in Malaysian patients is heterogeneous, with a slightly higher frequency of intron 22 inversion in these severe HA patients when compared to other Asian populations. Identification of these mutational profiles in F8 and F9 genes among Malaysian patients will provide a useful reference for the early detection and diagnosis of HA and HB in the Malaysian population.

    Matched MeSH terms: Sequence Analysis, DNA
  10. Chuah LO, Yap KP, Shamila-Syuhada AK, Thong KL, Ahmad R, Liong MT, et al.
    Int J Syst Evol Microbiol, 2017 Dec;67(12):4979-4985.
    PMID: 29034853 DOI: 10.1099/ijsem.0.002386
    Three strains of Gram-staining-positive, coccus-shaped, lactic acid bacteria, designated as HibF3T, HibF2 and HibF5 were isolated from fresh flowers of hibiscus, and a fourth, DF1T, was isolated from fresh flowers of durian tree, in Penang, Malaysia. Taxonomic characterisation was performed by polyphasic analysis. Sequence similarities of the 16S rRNA gene and the housekeeping rpoA and pheS genes of these strains with their closely-related lactococcal and streptococcal relatives were 92-94, 78 and 81 %, respectively. The results of phylogenetic analysis indicated that strains DF1T, HibF2, HibF5 and HibF3T were clustered together but were clearly separated from species of the genera Streptococcus and Lactococcus, indicating that they represent members of a novel genus of the family Streptococcaceae. Calculation of average nucleotide identity (ANI) values between the genomes of DF1T and HibF3T yielded values of 92.50-92.93 %. ANI values below the cut-off value and distinctive chemotaxonomic characteristics supported the hypothesis that these strains represented two novel species. Major cellular fatty acids in DF1T, HibF2 and HibF5 were C18 : 1ω7c and C16 : 0, while C12 : 0 and C14 : 0 were also dominant, in addition to C18 : 1ω7c and C16 : 0, in HibF3T. A novel genus is proposed with the name Floricoccus gen. nov. which consists of two species, Floricoccus tropicus sp. nov as the type species, and Floricoccus penangensis sp. nov. The respective type strains are DF1T (=LMG 29833T=JCM 31733T) and HibF3T (=LMG 29831T=DSM 31735T).
    Matched MeSH terms: Sequence Analysis, DNA
  11. Rahmatullah M, Ariff M, Kahieshesfandiari M, Daud HM, Zamri-Saad M, Sabri MY, et al.
    J Aquat Anim Health, 2017 Dec;29(4):208-213.
    PMID: 28787246 DOI: 10.1080/08997659.2017.1360411
    This study describes the isolation and pathogenicity of Streptococcus iniae in cultured red hybrid tilapia (Nile Tilapia Oreochromis niloticus × Mozambique Tilapia O. mossambicus) in Malaysia. The isolated gram-positive S. iniae appeared punctiform, transparently white, catalase and oxidase negative and produced complete β-hemolysis on blood agar, while a PCR assay resulted in the amplification of the 16 S rRNA gene and lactate oxidase encoded genes. The isolate was sensitive to tetracycline, vancomycin, and bacitracin but was resistant to streptomycin, ampicillin, penicillin, and erythromycin. Pathogenicity trials conducted in local red hybrid tilapia (mean ± SE = 20.00 ± 0.45 g) showed 90.0, 96.7, and 100.0% mortality within 14 d postinfection following intraperitoneal exposure to 104, 106, and 108 CFU/mL of the pathogen, respectively. The clinical signs included erratic swimming, lethargy, and inappetance at 6 h postinfection, while mortality was recorded at less than 24 h postinfection in all infected groups. The LD50-336 h of S. iniae against the red hybrid tilapia was 102 CFU/mL. The post mortem examinations revealed congested livers, kidneys, and spleens of the infected fish. This is the first report of S. iniae experimental infection in cultured red hybrid tilapia in Malaysia. Received January 20, 2017; accepted July 16, 2017.
    Matched MeSH terms: Sequence Analysis, DNA
  12. Ahmad MK, Tabana YM, Ahmed MA, Sandai DA, Mohamed R, Ismail IS, et al.
    Malays J Med Sci, 2017 Dec;24(6):29-38.
    PMID: 29379384 DOI: 10.21315/mjms2017.24.6.4
    Background: A norovirus maintains its viability, infectivity and virulence by its ability to replicate. However, the biological mechanisms of the process remain to be explored. In this work, the NanoLuc™ Luciferase gene was used to develop a reporter-tagged replicon system to study norovirus replication.

    Methods: The NanoLuc™ Luciferase reporter protein was engineered to be expressed as a fusion protein for MNV-1 minor capsid protein, VP2. The foot-and-mouth disease virus 2A (FMDV2A) sequence was inserted between the 3'end of the reporter gene and the VP2 start sequence to allow co-translational 'cleavage' of fusion proteins during intracellular transcript expression. Amplification of the fusion gene was performed using a series of standard and overlapping polymerase chain reactions. The resulting amplicon was then cloned into three readily available backbones of MNV-1 cDNA clones.

    Results: Restriction enzyme analysis indicated that the NanoLucTM Luciferase gene was successfully inserted into the parental MNV-1 cDNA clone. The insertion was further confirmed by using DNA sequencing.

    Conclusion: NanoLuc™ Luciferase-tagged MNV-1 cDNA clones were successfully engineered. Such clones can be exploited to develop robust experimental assays for in vitro assessments of viral RNA replication.

    Matched MeSH terms: Sequence Analysis, DNA
  13. Matsumoto T, Nanayakkara S, Perera D, Ushijima S, Wimalaratne O, Nishizono A, et al.
    Jpn J Infect Dis, 2017 Nov 22;70(6):693-695.
    PMID: 29093322 DOI: 10.7883/yoken.JJID.2017.249
    Matched MeSH terms: Sequence Analysis, DNA
  14. Sukantamala J, Sing KW, Jaturas N, Polseela R, Wilson JJ
    PMID: 27759464 DOI: 10.1080/24701394.2016.1214728
    Certain species of Phlebotomine sandflies (Diptera: Psychodidae) are vectors of the protozoa which causes leishmaniasis. Sandflies are found breeding in enclosed places like caves. Thailand is a popular tourist destination, including for ecotourism activities like caving, which increases the risk of contact between tourists and sandflies. Surveillance of sandflies is important for monitoring this risk but identification of species based on morphology is challenged by phenotypic plasticity and cryptic diversity. DNA barcodes have been used for the identification of sandflies in Thailand. We collected sandflies using CDC light trap from four tourist caves in Northern Thailand. Female sandflies were provisionally sorted into 13 morphospecies and 19 unidentified specimens. DNA was extracted from the thorax and legs of sandflies and the DNA barcode region of cytochrome c oxidase I mtDNA amplified and sequenced. The specimens were sorted into 22 molecular operational taxonomic units (MOTU) based on the 145 DNA barcodes, which is significantly more than the morphospecies. Several of the taxa thought to be present in multiple caves, based on morphospecies sorting, split into cave-specific MOTU which likely represent cryptic species. Several MOTU reported in an earlier study from Wihan Cave, Thailand, were also found in these caves. This supports the use of DNA barcodes to investigate species diversity of sandflies and their useful role in surveillance of sandflies in Thailand.
    Matched MeSH terms: Sequence Analysis, DNA
  15. Li YY, Liu H, Fu SH, Li XL, Guo XF, Li MH, et al.
    Infect Genet Evol, 2017 11;55:48-55.
    PMID: 28827175 DOI: 10.1016/j.meegid.2017.08.016
    Getah virus (GETV) was first isolated in Malaysia in 1955. Since then, epidemics in horses and pigs caused by GETV have resulted in huge economic losses. At present, GETV has spread across Eurasia and Southeast Asia, including mainland China, Korea, Japan, Mongolia, and Russia. Data show that the Most Recent Common Ancestor (MRCA) of GETV existed about 145years ago (95% HPD: 75-244) and gradually evolved into four distinct evolutionary populations: Groups I-IV. The MRCA of GETVs in Group III, which includes all GETVs isolated from mosquitoes, pigs, horses, and other animals since the 1960s (from latitude 19°N to 60°N), existed about 51years ago (95% HPD: 51-72). Group III is responsible for most viral epidemics among domestic animals. An analysis of the GETV E2 protein sequence and structure revealed seven common amino acid mutation sites. These sites are responsible for the structural and electrostatic differences detected between widespread Group III isolates and the prototype strain MM2021. These differences may account for the recent geographical radiation of the virus. Considering the economic significance of GETV infection in pigs and horses, we recommend the implementation of strict viral screening and monitoring programs.
    Matched MeSH terms: Sequence Analysis, DNA
  16. Sadeghi M, Popov V, Guzman H, Phan TG, Vasilakis N, Tesh R, et al.
    Virus Res, 2017 10 15;242:49-57.
    PMID: 28855097 DOI: 10.1016/j.virusres.2017.08.012
    Eleven viral isolates derived mostly in albopictus C6/36 cells from mosquito pools collected in Southeast Asia and the Americas between 1966 and 2014 contained particles with electron microscopy morphology typical of reoviruses. Metagenomics analysis yielded the near complete genomes of three novel reoviruses, Big Cypress orbivirus, Ninarumi virus, and High Island virus and a new tetravirus, Sarawak virus. Strains of previously characterized Sathuvarachi, Yunnan, Banna and Parry's Lagoon viruses (Reoviridae), Bontang virus (Mesoniviridae), and Culex theileri flavivirus (Flaviviridae) were also characterized. The availability of these mosquito virus genomes will facilitate their detection by metagenomics or PCR to better determine their geographic range, extent of host tropism, and possible association with arthropod or vertebrate disease.
    Matched MeSH terms: Sequence Analysis, DNA
  17. Pipatchartlearnwong K, Swatdipong A, Vuttipongchaikij S, Apisitwanich S
    BMC Genet, 2017 10 12;18(1):88.
    PMID: 29025415 DOI: 10.1186/s12863-017-0554-y
    BACKGROUND: Borassus flabellifer or Asian Palmyra palm is an important crop for local economies in the South and Southeast Asia for its fruit and palm sugar production. Archeological and historical evidence indicated the presence of this species in Southeast Asia dating back at least 1500 years. B. flabellifer is believed to be originated in Africa, spread to South Asia and introduced into Southeast Asia through commercial routes and dissemination of cultures, however, the nature of its invasion and settlement in Thailand is unclear.

    RESULTS: Here, we analyzed genetic data of 230 B. flabellifer accessions across Thailand using 17 EST-SSR and 12 gSSR polymorphic markers. Clustering analysis revealed that the population consisted of two genetic clusters (STRUCTURE K = 2). Cluster I is found mainly in southern Thailand, while Cluster II is found mainly in the northeastern. Those found in the central are of an extensive mix between the two. These two clusters are in moderate differentiation (F ST = 0.066 and N M = 3.532) and have low genetic diversity (HO = 0.371 and 0.416; AR = 2.99 and 3.19, for the cluster I and II respectively). The minimum numbers of founders for each genetic group varies from 3 to 4 individuals, based on simulation using different allele frequency assumptions. These numbers coincide with that B. flabellifer is dioecious, and a number of seeds had to be simultaneously introduced for obtaining both male and female founders.

    CONCLUSIONS: From these data and geographical and historical evidence, we hypothesize that there were at least two different invasive events of B. flabellifer in Thailand. B. flabellifer was likely brought through the Straits of Malacca to be propagated in the southern Thailand as one of the invasive events before spreading to the central Thailand. The second event likely occurred in Khmer Empire, currently Cambodia, before spreading to the northeastern Thailand.

    Matched MeSH terms: Sequence Analysis, DNA/methods*
  18. Yap NJ, Goh XT, Koehler AV, William T, Yeo TW, Vythilingam I, et al.
    Infect Genet Evol, 2017 10;54:39-46.
    PMID: 28634105 DOI: 10.1016/j.meegid.2017.06.019
    Plasmodium knowlesi, a malaria parasite of macaques, has emerged as an important parasite of humans. Despite the significance of P. knowlesi malaria in parts of Southeast Asia, very little is known about the genetic variation in this parasite. Our aim here was to explore sequence variation in a molecule called the 42kDa merozoite surface protein-1 (MSP-1), which is found on the surface of blood stages of Plasmodium spp. and plays a key role in erythrocyte invasion. Several studies of P. falciparum have reported that the C-terminus (a 42kDa fragment) of merozoite surface protein-1 (MSP-142; consisting of MSP-119 and MSP-133) is a potential candidate for a malaria vaccine. However, to date, no study has yet investigated the sequence diversity of the gene encoding P. knowlesi MSP-142 (comprising Pk-msp-119 and Pk-msp-133) among isolates in Malaysia. The present study explored this aspect. Twelve P. knowlesi isolates were collected from patients from hospitals in Selangor and Sabah Borneo, Malaysia, between 2012 and 2014. The Pk-msp-142 gene was amplified by PCR and directly sequenced. Haplotype diversity (Hd) and nucleotide diversity (л) were studied among the isolates. There was relatively high genetic variation among P. knowlesi isolates; overall Hd and л were 1±0.034 and 0.01132±0.00124, respectively. A total of nine different haplotypes related to amino acid alterations at 13 positions, and the Pk-MSP-119 sequence was found to be more conserved than Pk-msp-133. We have found evidence for negative selection in Pk-msp-42 as well as the 33kDa and 19kDa fragments by comparing the rate of non-synonymous versus synonymous substitutions. Future investigations should study large numbers of samples from disparate geographical locations to critically assess whether this molecule might be a potential vaccine target for P. knowlesi.
    Matched MeSH terms: Sequence Analysis, DNA
  19. Kanniappan P, Ahmed SA, Rajasekaram G, Marimuthu C, Ch'ng ES, Lee LP, et al.
    J Cell Mol Med, 2017 10;21(10):2276-2283.
    PMID: 28756649 DOI: 10.1111/jcmm.13148
    Technological advances in RNA biology greatly improved transcriptome profiling during the last two decades. Besides the discovery of many small RNAs (sRNA) that are involved in the physiological and pathophysiological regulation of various cellular circuits, it becomes evident that the corresponding RNA genes might also serve as potential biomarkers to monitor the progression of disease and treatment. sRNA gene candidate npcTB_6715 was previously identified via experimental RNomic (unpublished data), and we report its application as potential biomarker for the detection of Mycobacterium tuberculosis (MTB) in patient samples. For proof of principle, we developed a multiplex PCR assay and report its validation with 500 clinical cultures, positive for Mycobacteria. The analysis revealed 98.9% sensitivity, 96.1% specificity, positive and negative predictive values of 98.6% and 96.8%, respectively. These results underscore the diagnostic value of the sRNA gene as diagnostic marker for the specific detection of MTB in clinical samples. Its successful application and the general ease of PCR-based detection compared to standard bacterial culture techniques might be the first step towards 'point-of-care' diagnostics of Mycobacteria. To the best of our knowledge, this is the first time for the design of diagnostic applications based on sRNA genes, in Mycobacteria.
    Matched MeSH terms: Sequence Analysis, DNA/methods
  20. Balakrishnan KN, Abdullah AA, Bala J, Abba Y, Sarah SA, Jesse FFA, et al.
    Infect Genet Evol, 2017 10;54:81-90.
    PMID: 28642159 DOI: 10.1016/j.meegid.2017.06.020
    BACKGROUND: Rat cytomegalovirus ALL-03 (Malaysian strain) which was isolated from a placenta and uterus of a house rat, Rattus rattus diardii has the ability to cross the placenta and infecting the fetus. To further elucidate the pathogenesis of the Malaysian strain of Rat Cytomegalovirus ALL-03 (RCMV ALL-03), detailed analysis on the viral genome sequence is crucial.

    METHODS: Genome sequencing of RCMV ALL-03 was carried out in order to identify the open reading frame (ORF), homology comparison of ORF with other strains of CMV, phylogenetic analysis, classifying ORF with its corresponding conserved genes, and determination of functional proteins and grouping of gene families in order to obtain fundamental knowledge of the genome.

    RESULTS: The present study revealed a total of 123 Coding DNA sequences (CDS) from RCMV ALL-03 with 37 conserved ORF domains as with all herpesvirus genomes. All the CDS possess similar function with RCMV-England followed by RCMV-Berlin, RCMV-Maastricht, and Human CMV. The phylogenetic analysis of RCMV ALL-03 based on conserving genes of herpes virus showed that the Malaysian RCMV isolate is closest to RCMV-English and RCMV-Berlin strains, with 99% and 97% homology, respectively. Similarly, it also demonstrated an evolutionary relationship between RCMV ALL-03 and other strains of herpesviruses from all the three subfamilies. Interestingly, betaherpesvirus subfamily, which has been shown to be more closely related with gammaherpesviruses as compared to alphaherpesviruses, shares some of the functional ORFs. In addition, the arrangement of gene blocks for RCMV ALL-03, which was conserved among herpesvirus family members was also observed in the RCMV ALL-03 genome.

    CONCLUSION: Genomic analysis of RCMV ALL-03 provided an overall picture of the whole genome organization and it served as a good platform for further understanding on the divergence in the family of Herpesviridae.

    Matched MeSH terms: Sequence Analysis, DNA
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