Displaying publications 21 - 40 of 59 in total

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  1. Three stage cultivation process of facultative strain of Chlorella sorokiniana for treating dairy farm effluent and lipid enhancement
    Hena S, Fatihah N, Tabassum S, Ismail N
    Water Res, 2015 Sep 1;80:346-56.
    PMID: 26043271 DOI: 10.1016/j.watres.2015.05.001
    Reserve lipids of microalgae are promising for biodiesel production. However, economically feasible and sustainable energy production from microalgae requires optimization of cultivation conditions for both biomass yield and lipid production of microalgae. Biomass yield and lipid production in microalgae are a contradictory problem because required conditions for both targets are different. Simultaneously, the mass cultivation of microalgae for biofuel production also depends extremely on the performance of the microalgae strains used. In this study a green unicellular microalgae Chlorella sorokiniana (DS6) isolated from the holding tanks of farm wastewater treatment plant using multi-step screening and acclimation procedures was found high-lipid producing facultative heterotrophic microalgae strain capable of growing on dairy farm effluent (DFE) for biodiesel feedstock and wastewater treatment. Morphological features and the phylogenetic analysis for the 18S rRNA identified the isolated strains. A novel three stage cultivation process of facultative strain of C. sorokiniana was examined for lipid production.
    Matched MeSH terms: RNA, Ribosomal, 18S/genetics
  2. Fulltext Molecular epidemiology of Cryptosporidium in HIV/AIDS patients in Malaysia
    Asma I, Sim BL, Brent RD, Johari S, Yvonne Lim AL
    Trop Biomed, 2015 Jun;32(2):310-22.
    PMID: 26691260 MyJurnal
    Cryptosporidiosis is a particular concern in immunocompromised individuals where symptoms may be severe. The aim of this study was to examine the epidemiological and molecular characteristics of Cryptosporidium infections in HIV/AIDS patients in Malaysia in order to identify risk factors and facilitate control measures. A modified Ziehl-Neelsen acid fast staining method was used to test for the presence of Cryptosporidium oocysts in the stools of 346 HIV/AIDS patients in Malaysia. Standard coproscopical methods were used to identify infections with other protozoan or helminths parasites. To identify the species of Cryptosporidium, DNA was extracted and nested-PCR was used to amplify a portion of the SSU rRNA gene. A total of 43 (12.4%) HIV-infected patients were found to be infected with Cryptosporidium spp. Of the 43 Cryptosporidium-positive HIV patients, 10 (23.3%) also harboured other protozoa, and 15 (34.9%) had both protozoa and helminths. The highest rates of cryptosporidiosis were found in adult males of Malay background, intravenous drug users, and those with low CD4 T cell counts (i.e., < 200 cells/mm3). Most were asymptomatic and had concurrent opportunistic infections mainly with Mycobacterium tuberculosis. DNA sequence analysis of 32 Cryptosporidium isolates identified C. parvum (84.3%), C. hominis (6.3%), C. meleagridis (6.3%), and C. felis (3.1%). The results of the present study revealed a high prevalence of Cryptosporidium infection in hospitalized HIV/AIDS patients. The results also confirmed the potential significance of zoonotic transmission of C. parvum in HIV infected patients, as it was the predominant species found in this study. However, these patients were found to be susceptible to a wide range of Cryptosporidium species. Epidemiological and molecular characterization of Cryptosporidium isolates provides clinicians and researchers with further information regarding the origin of the infection, and may enhance treatment and control strategies.
    Matched MeSH terms: RNA, Ribosomal, 18S/genetics
  3. Fulltext High prevalence of muscular sarcocystosis in cattle and water buffaloes from Selangor, Malaysia
    Latif B, Vellayan S, Heo CC, Kannan Kutty M, Omar E, Abdullah S, et al.
    Trop Biomed, 2013 Dec;30(4):699-705.
    PMID: 24522140 MyJurnal
    The prevalence of sarcocystosis in cattle and water buffaloes from peninsular Malaysia was investigated in abattoirs in Selangor state, February, 2011, to March, 2012. Fresh muscle samples were collected from the tongue, heart, oesophagus, diaphragm and skeletal muscles of 102 cattle and 18 water buffaloes. Each sample was initially screened by light microscopy and then fixed for further histopathological analysis. Out of 120 animals examined, 49 (40.8%) harboured the microscopic type of Sarcocystis spp. The positivity rate for cattle was 36.2% and for water buffaloes 66.7%. In cattle, the organs highly infected were the skeletal muscles and diaphragm (27% each), followed by tongue and esophagus (24.3% each), and the heart (8%). In water buffaloes, the heart was most often infected (66.7%), followed by the oesophagus (50%) and skeletal muscle (33.3%); no sarcocysts were detected in the tongue and diaphragm. The shape of the sarcocyst was fusiform to oval with a mean cyst size of 151.66 x 75.83 μm and wall thickness of 2.47 μm in cattle, and 114 x 50.81 μm cyst size and the wall thickness of 1.11 μm in water buffaloes, consistent with Sarcocystis cruzi and Sarcocystis levinei, respectively. Remaining tissue from cattle was subjected to parasite specific 18S rRNA gene PCR and Sarcocystis cruzi was confirmed, at least exemplarily. The peripheral metrocytes and the banana-shaped bradyzoites (15.23 x 2.2 μm in cattle and 11.49 x 2.45 μm in water buffalo hosts) were easily recognized. In conclusion, a high positivity rate was found in Malaysian meat-producing animals with possible implications for meat consumption and human health.
    Matched MeSH terms: RNA, Ribosomal, 18S/genetics
  4. Fulltext Henneguya (Cnidaria: Myxosporea: Myxobolidae) infections of cultured barramundi, Lates calcarifer (Perciformes: Latidae) in an estuarine wetlands system of Malaysia: description of Henneguya setiuensis n. sp., Henneguya voronini n. sp. and Henneguya calcarifer n. sp
    Borkhanuddin MH, Cech G, Molnár K, Shaharom-Harrison F, Khoa TND, Samshuri MA, et al.
    Parasitol Res, 2020 Jan;119(1):85-96.
    PMID: 31768684 DOI: 10.1007/s00436-019-06541-1
    Examination of 35 barramundi (Lates calcarifer) from aquaculture cages in Setiu Wetland, Malaysia, revealed a single fish infected with three Henneguya spp. (Cnidaria: Myxosporea). Characterization of the infections using tissue tropism, myxospore morphology and morphometry and 18S rDNA sequencing supported description of three new species: Henneguya setiuensis n. sp., Henneguya voronini n. sp. and H. calcarifer n. sp. Myxospores of all three species had typical Henneguya morphology, with two polar capsules in the plane of the suture, an oval spore body, smooth valve cell surfaces, and two caudal appendages. Spores were morphometrically similar, and many dimensions overlapped, but H. voronini n. sp. had shorter caudal appendages compared with H. calcarifer n. sp. and H. setiuensis n. sp. Gross tissue tropism distinguished the muscle parasite H. calcarifer n. sp. from gill parasites H. setiuensis n. sp. and H. voronini n. sp.; and these latter two species were further separable by fine-scale location of developing plasmodia, which were intra-lamellar for H. setiuensis n. sp. and basal to the filaments for H. voronini n. sp. small subunit ribosomal DNA sequences distinguished all three species: the two gill species H. setiuensis n. sp. and H voronini n. sp. were only 88% similar (over 1708 bp), whereas the muscle species H. calcarifer n. sp. was most similar to H. voronini n. sp. (98% over 1696 bp). None of the three novel species was more than 90% similar to any known myxosporean sequence in GenBank. Low infection prevalence of these myxosporeans and lack of obvious tissue pathology from developing plasmodia suggested none of these parasites are currently a problem for barramundi culture in Setiu Wetland; however additional surveys of fish, particularly at different times of the year, would be informative for better risk assessment.
    Matched MeSH terms: RNA, Ribosomal, 18S/genetics
  5. Fulltext Hexaplex PCR detection system for identification of five human Plasmodium species with an internal control
    Chew CH, Lim YA, Lee PC, Mahmud R, Chua KH
    J Clin Microbiol, 2012 Dec;50(12):4012-9.
    PMID: 23035191 DOI: 10.1128/JCM.06454-11
    Malaria remains one of the major killers of humankind and persists to threaten the lives of more than one-third of the world's population. Given that human malaria can now be caused by five species of Plasmodium, i.e., Plasmodium falciparum, Plasmodium vivax, Plasmodium malariae, Plasmodium ovale, and the recently included Plasmodium knowlesi, there is a critical need not only to augment global health efforts in malaria control but also, more importantly, to develop a rapid, accurate, species-sensitive/species-specific, and economically effective diagnostic method for malaria caused by these five species. Therefore, in the present study, a straightforward single-step hexaplex PCR system targeting five human Plasmodium 18S small-subunit rRNAs (ssu rRNAs) was designed, and the system successfully detected all five human malaria parasites. In addition, this system enables the differentiation of single infection as well as mixed infections up to the two-species level. This assay was validated with 50 randomly blinded test and 184 clinical samples suspected to indicate malaria. This hexaplex PCR system is not only an ideal alternative for routine malaria diagnosis in laboratories with conventional PCR machines but also adds value to diagnoses when there is a lack of an experienced microscopist or/and when the parasite morphology is confusing. Indeed, this system will definitely enhance the accuracy and accelerate the speed in the diagnosis of malaria, as well as improve the efficacy of malaria treatment and control, in addition to providing reliable data from epidemiological surveillance studies.
    Matched MeSH terms: RNA, Ribosomal, 18S/genetics
  6. Molecular detection and genetic diversity of Babesia gibsoni in dogs in Bangladesh
    Terao M, Akter S, Yasin MG, Nakao R, Kato H, Alam MZ, et al.
    Infect Genet Evol, 2015 Apr;31:53-60.
    PMID: 25620376 DOI: 10.1016/j.meegid.2015.01.011
    Babesia gibsoni is a tick-borne hemoprotozoan parasite of dogs that often causes fever and hemolytic illness. Detection of B. gibsoni has been predominantly reported in Asian countries, including Japan, Korea, Taiwan, Malaysia, Bangladesh and India. The present study shows the first molecular characterization of B. gibsoni detected from dogs in Bangladesh. Blood samples were collected on FTA® Elute cards from 50 stray dogs in Mymensingh District in Bangladesh. DNA eluted from the cards was subjected to nested PCR for the 18S rRNA gene of Babesia species. Approximately 800bp PCR products were detected in 15 of 50 dogs (30%). Based on restriction fragment length polymorphism (RFLP) and direct sequencing of the PCR products, all parasite isolates were identified as B. gibsoni. Furthermore, the BgTRAP (B. gibsoni thrombospondin-related adhesive protein) gene fragments were detected in 13 of 15 18S rRNA gene PCR positive blood samples. Phylogenetic analysis of the BgTRAP gene revealed that B. gibsoni parasites in Bangladesh formed a cluster, which was genetically different from other Asian B. gibsoni isolates. In addition, tandem repeat analysis of the BgTRAP gene clearly showed considerable genetic variation among Bangladeshi isolates. These results suggested that B. gibsoni parasites in a different genetic clade are endemic in dogs in Bangladesh. Further studies are required to elucidate the origin, distribution, vector and pathogenesis of B. gibsoni parasites circulating in dogs in Bangladesh.
    Matched MeSH terms: RNA, Ribosomal, 18S/genetics
  7. Isolation, screening, and identification of potential cellulolytic and xylanolytic producers for biodegradation of untreated oil palm trunk and its application in saccharification of lemongrass leaves
    Ang SK, Yahya A, Abd Aziz S, Md Salleh M
    Prep Biochem Biotechnol, 2015;45(3):279-305.
    PMID: 24960316 DOI: 10.1080/10826068.2014.923443
    This study presents the isolation and screening of fungi with excellent ability to degrade untreated oil palm trunk (OPT) in a solid-state fermentation system (SSF). Qualitative assay of cellulases and xylanase indicates notable secretion of both enzymes by 12 fungal strains from a laboratory collection and 5 strains isolated from a contaminated wooden board. High production of these enzymes was subsequently quantified in OPT in SSF. Aspergillus fumigates SK1 isolated from cow dung gives the highest xylanolytic activity (648.448 U g(-1)), generally high cellulolytic activities (CMCase: 48.006, FPase: 6.860, beta-glucosidase: 16.328 U g(-1)) and moderate lignin peroxidase activity (4.820 U/g), and highest xylanolytic activity. The xylanase encoding gene of Aspergillus fumigates SK1 was screened using polymerase chain reaction by a pair of degenerate primers. Through multiple alignment of the SK1 strain's xylanase nucleotide sequences with other published xylanases, it was confirmed that the gene belonged to the xylanase glycoside hydrolase family 11 (GH11) with a protein size of 24.49 kD. Saccharification of lemongrass leaves using crude cellulases and xylanase gives the maximum reducing sugars production of 6.84 g/L with glucose as the major end product and traces of phenylpropanic compounds (vanillic acid, p-coumaric acid, and ferulic acid).
    Matched MeSH terms: RNA, Ribosomal, 18S/genetics
  8. Fulltext High proportion of knowlesi malaria in recent malaria cases in Malaysia
    Yusof R, Lau YL, Mahmud R, Fong MY, Jelip J, Ngian HU, et al.
    Malar J, 2014;13:168.
    PMID: 24886266 DOI: 10.1186/1475-2875-13-168
    Plasmodium knowlesi is a simian parasite that has been recognized as the fifth species causing human malaria. Naturally-acquired P. knowlesi infection is widespread among human populations in Southeast Asia. The aim of this epidemiological study was to determine the incidence and distribution of malaria parasites, with a particular focus on human P. knowlesi infection in Malaysia.
    Matched MeSH terms: RNA, Ribosomal, 18S/genetics
  9. Gold-nanoparticle based electrochemical DNA sensor for the detection of fish pathogen Aphanomyces invadans
    Kuan GC, Sheng LP, Rijiravanich P, Marimuthu K, Ravichandran M, Yin LS, et al.
    Talanta, 2013 Dec 15;117:312-7.
    PMID: 24209346 DOI: 10.1016/j.talanta.2013.09.016
    Epizootic ulcerative syndrome (EUS) is a devastating fish disease caused by the fungus, Aphanomyces invadans. Rapid diagnosis of EUS is needed to control and treat this highly invasive disease. The current diagnostic methods for EUS are labor intensive. We have developed a highly sensitive and specific electrochemical genosensor towards the 18S rRNA and internal transcribed spacer regions of A. invadans. Multiple layers of latex were synthesized with the help of polyelectrolytes, and labeled with gold nanoparticles to enhance sensitivity. The gold-latex spheres were functionalized with specific DNA probes. We describe here the novel application of this improved platform for detection of PCR product from real sample of A. invadans using a premix sandwich hybridization assay. The premix assay was easier, more specific and gave higher sensitivity of one log unit when compared to the conventional method of step-by-step hybridization. The limit of detection was 0.5 fM (4.99 zmol) of linear target DNA and 1 fM (10 amol) of PCR product. The binding positions of the probes to the PCR amplicons were optimized for efficient hybridization. Probes that hybridized close to the 5' or 3' terminus of the PCR amplicons gave the highest signal due to minimal steric hindrance for hybridization. The genosensor is highly suitable as a surveillance and diagnostic tool for EUS in the aquaculture industry.
    Matched MeSH terms: RNA, Ribosomal, 18S/genetics*
  10. Molecular identification of Aspergillus and Eurotium species isolated from rice and their toxin-producing ability
    Yazdani D, Zainal Abidin MA, Tan YH, Kamaruzaman S
    Mikrobiologiia, 2011 Sep-Oct;80(5):707-13.
    PMID: 22168015
    Thirty milled rice samples were collected from retailers in 4 provinces of Malaysia. These samples were evaluated for Aspergillus spp. infection by direct plating on malt extract salt agar (MESA). All Aspergillus holomorphs were isolated and identified using nucleotide sequences of ITS 1 and ITS 2 of rDNA. Five anamorphs (Aspergillus flavus, A. oryzae, A. tamarii, A. fumigatus and A. niger) and 5 teleomorphs (Eurotium rubrum, E. amstelodami, E. chevalieri, E. cristatum and E. tonophilum) were identified. The PCR-sequencing based technique for sequences of ITS 1 and ITS 2 is a fast technique for identification of Aspergillus and Eurotium species, although it doesn't work flawlessly for differentiation of Eurotium species. All Aspergillus and Eurotium isolates were screened for their ability to produce aflatoxin and ochratoxin A (OTA) by HPLC and TLC techniques. Only A. flavus isolate UPM 89 was able to produce aflatoxins B1 and B2.
    Matched MeSH terms: RNA, Ribosomal, 18S/genetics
  11. 'Babesia gibsoni' of dogs from North America and Asia belong to different species
    Zahler M, Rinder H, Zweygarth E, Fukata T, Maede Y, Schein E, et al.
    Parasitology, 2000 Apr;120 ( Pt 4):365-9.
    PMID: 10811277
    18S rDNA sequences from 4 isolates of Babesia gibsoni originating from Japan, Malaysia and Sri Lanka were compared with a previously published, 0.5 kb portion of the 18S rDNA from a B. gibsoni isolate from California, USA, and with the corresponding 18S rDNA sequences of other Babesia spp. Distance, parsimony and maximum likelihood analyses showed almost identical genotypes among the small canine Babesia from Asia, but an unexpectedly distant genetic relationship to that from the USA. While the American isolate segregated together with B. equi, the Asian isolates showed a close relationship to B. divergens and B. odocoilei. These results indicate that small Babesia of dogs originating from North America and Asia belong to different, genetically distantly related species.
    Matched MeSH terms: RNA, Ribosomal, 18S/genetics
  12. Chromosomal Locations of a Non-LTR Retrotransposon, Menolird18, in Cucumis melo and Cucumis sativus, and Its Implication on Genome Evolution of Cucumis Species
    Setiawan AB, Teo CH, Kikuchi S, Sassa H, Kato K, Koba T
    Cytogenet Genome Res, 2020;160(9):554-564.
    PMID: 33171461 DOI: 10.1159/000511119
    Mobile elements are major regulators of genome evolution through their effects on genome size and chromosome structure in higher organisms. Non-long terminal repeat (non-LTR) retrotransposons, one of the subclasses of transposons, are specifically inserted into repetitive DNA sequences. While studies on the insertion of non-LTR retrotransposons into ribosomal RNA genes and other repetitive DNA sequences have been reported in the animal kingdom, studies in the plant kingdom are limited. Here, using FISH, we confirmed that Menolird18, a member of LINE (long interspersed nuclear element) in non-LTR retrotransposons and found in Cucumis melo, was inserted into ITS and ETS (internal and external transcribed spacers) regions of 18S rDNA in melon and cucumber. Beside the 18S rDNA regions, Menolird18 was also detected in all centromeric regions of melon, while it was located at pericentromeric and sub-telomeric regions in cucumber. The fact that FISH signals of Menolird18 were found in centromeric and rDNA regions of mitotic chromosomes suggests that Menolird18 is a rDNA and centromere-specific non-LTR retrotransposon in melon. Our findings are the first report on a non-LTR retrotransposon that is highly conserved in 2 different plant species, melon and cucumber. The clear distinction of chromosomal localization of Menolird18 in melon and cucumber implies that it might have been involved in the evolutionary processes of the melon (C. melo) and cucumber (C. sativus) genomes.
    Matched MeSH terms: RNA, Ribosomal, 18S/genetics
  13. Fulltext Myxozoan infections in fishes of the Tasik Kenyir Water Reservoir, Terengganu, Malaysia
    Székely C, Shaharom-Harrison F, Cech G, Ostoros G, Molnár K
    Dis Aquat Organ, 2009 Jan 28;83(1):37-48.
    PMID: 19301635 DOI: 10.3354/dao01991
    During a survey on fishes of the Tasik Kenyir Reservoir, Malaysia, 5 new Myxobolus spp. and 2 known Henneguya spp. were found. The specific locations for 2 Myxobolus spp. were the host's muscles, while 2 other Myxobolus spp. were found to develop in the host's kidney and gills, respectively. Of the species developing intracellularly in muscle cells, M. terengganuensis sp. nov. was described from Osteochilus hasselti and M. tasikkenyirensis sp. nov. from Osteochilus vittatus. M. csabai sp. nov. and M. osteochili sp. nov. were isolated from the kidney of Osteochilus hasselti, while M. dykovae sp. nov. was found in the gill lamellae of Barbonymus schwanenfeldii. Henneguya shaharini and Henneguya hemibagri plasmodia were found on the gills of Oxyeleotris marmoratus and Hemibagrus nemurus, respectively. Description of the new and known species was based on morphological characterization of spores, histological findings on locations of plasmodia and DNA sequence data.
    Matched MeSH terms: RNA, Ribosomal, 18S/genetics
  14. Fulltext From 18S to 28S rRNA Gene: An Improved Targeted Sarcocystidae PCR Amplification, Species Identification with Long DNA Sequences
    Lee FCH, Muthu V
    Am J Trop Med Hyg, 2021 02 22;104(4):1388-1393.
    PMID: 33617472 DOI: 10.4269/ajtmh.20-0767
    Sarcocystosis outbreaks in Tioman and Pangkor islands of Malaysia between 2011 and 2014 have raised the need to improve Sarcocystis species detection from environmental samples. In-house works found that published primers amplifying the 18S rRNA gene of Sarcocystis either could not produce the target from environmental samples or produced Sarcocystis DNA sequence that was insufficient for species identification. Using the primer pair of 18S S5 F (published) and 28S R6 R (new), this study improved the PCR amplification of Sarcocystidae to overcome these two difficulties. The PCR product spanned from the 18S to 28S rRNA genes, providing more information for species identification. The long DNA sequence allowed comparison between the "Ident" and "Query Cover" sorting in GenBank identity matching. This revealed the ambiguity in identity matching caused by different lengths of reference DNA sequences, which is seldom discussed in the literature. Using the disparity index test, a measurement of homogeneity in nucleotide substitution pattern, it is shown that the internal transcribed spacer (ITS)1-5.8S-ITS2 and 28S genes are better than the 18S gene in indicating nucleotide variations, implying better potentials for species identification. The example given by the handful of Sarcocystidae long DNA sequences reported herein calls for the need to report DNA sequence from the 18S to the 28S rRNA genes for species identification, especially among emerging pathogens. DNA sequence reporting should include the hypervariable 5.8S and ITS2 regions where applicable, and not be limited to single gene, per the current general trend.
    Matched MeSH terms: RNA, Ribosomal, 18S/genetics*
  15. Molecular evidence of Sarcocystis nesbitti in water samples of Tioman Island, Malaysia
    Shahari S, Tengku-Idris TI, Fong MY, Lau YL
    Parasit Vectors, 2016 11 23;9(1):598.
    PMID: 27881179
    BACKGROUND: Sarcocystis are intracellular protozoan parasites that are characterised by their ability to invade muscle tissue and form intramuscular sarcocysts. A muscular sarcocystosis outbreak was reported by travellers returning from Tioman Island in 2011 and 2012 where Sarcocystis nesbitti was identified as the main cause. The source of the S. nesbitti that was involved has remained elusive, although water is hypothesised to be the main cause of transmission. A surveillance study was therefore undertaken in the northern regions of Tioman Island to identify the source of S. nesbitti by screening rivers, water tanks, wells and seawater.

    METHODS: Water samples were collected from rivers, water tanks, wells and seawater on Tioman Island over the course of April to October 2015. Water samples were indirectly screened for Sarcocystis species by obtaining sediment from respective water sources. PCR amplification of the 18S rRNA gene region was conducted to identify positive samples. Microscopy was used in an attempt to reappraise PCR results, but no sporocysts were detected in any of the samples.

    RESULTS: A total of 157 water samples were obtained and 19 were positive for various Sarcocystis species. Through BLASTn and phylogenetic analysis, these species were found to be S. singaporensis, S. nesbitti, Sarcocystis sp. YLL-2013 and one unidentified Sarcocystis species.

    CONCLUSIONS: This is the first positive finding of S. nesbitti in water samples on Tioman Island, which was found in a water tank and in river water samples. This finding supports the hypothesis that water was a potential medium for the transmission of S. nesbitti during the outbreak. This will potentially identify areas in which preventive measures can be taken to prevent future outbreaks.

    Matched MeSH terms: RNA, Ribosomal, 18S/genetics
  16. The life cycle of Thelohanellus kitauei (Myxozoa: Myxosporea) infecting common carp (Cyprinus carpio) involves aurantiactinomyxon in Branchiura sowerbyi
    Zhao D, Borkhanuddin MH, Wang W, Liu Y, Cech G, Zhai Y, et al.
    Parasitol Res, 2016 Nov;115(11):4317-4325.
    PMID: 27492197
    Thelohanellus kitauei is a freshwater myxosporean parasite causing intestinal giant cystic disease of common carp. To clarify the life cycle of T. kitauei, we investigated the oligochaete populations in China and Hungary. This study confirms two distinct aurantiactinomyxon morphotypes (Aurantiactinomyxon type 1 and Aurantiactinomyxon type 2) from Branchiura sowerbyi as developmental stages of the life cycle of T. kitauei. The morphological characteristics and DNA sequences of these two types are described here. Based on 18S rDNA sequence analysis, Aurantiactinomyxon type 1 (2048 bp) and Aurantiactinomyxon type 2 (2031 bp) share 99.2-99.4 %, 99.8-100 % similarity to the published sequences of T. kitauei, respectively. The 18S rDNA sequences of these two aurantiactinomyxon morphotypes share 99.4 % similarity, suggesting intraspecific variation within the taxon, possibly due to geographic origin. Phylogenetic analyses demonstrate the two aurantiactinomyxon types clustered with T. kitauei. Regardless, based on 18S rDNA synonymy, it is likely that Aurantiactinomyxon type 1 and 2 are conspecific with T. kitauei. This is the fourth elucidated two-host life cycle of Thelohanellus species and the first record of T. kitauei in Europe.
    Matched MeSH terms: RNA, Ribosomal, 18S/genetics
  17. Fulltext Phylogeographic Evidence for 2 Genetically Distinct Zoonotic Plasmodium knowlesi Parasites, Malaysia
    Yusof R, Ahmed MA, Jelip J, Ngian HU, Mustakim S, Hussin HM, et al.
    Emerg Infect Dis, 2016 Aug;22(8):1371-80.
    PMID: 27433965 DOI: 10.3201/eid2208.151885
    Infections of humans with the zoonotic simian malaria parasite Plasmodium knowlesi occur throughout Southeast Asia, although most cases have occurred in Malaysia, where P. knowlesi is now the dominant malaria species. This apparently skewed distribution prompted an investigation of the phylogeography of this parasite in 2 geographically separated regions of Malaysia, Peninsular Malaysia and Malaysian Borneo. We investigated samples collected from humans and macaques in these regions. Haplotype network analyses of sequences from 2 P. knowlesi genes, type A small subunit ribosomal 18S RNA and cytochrome c oxidase subunit I, showed 2 genetically distinct divergent clusters, 1 from each of the 2 regions of Malaysia. We propose that these parasites represent 2 distinct P. knowlesi types that independently became zoonotic. These types would have evolved after the sea-level rise at the end of the last ice age, which separated Malaysian Borneo from Peninsular Malaysia.
    Matched MeSH terms: RNA, Ribosomal, 18S/genetics
  18. Fulltext Loop-Mediated Isothermal Amplification Assay for Identification of Five Human Plasmodium Species in Malaysia
    Lau YL, Lai MY, Fong MY, Jelip J, Mahmud R
    Am J Trop Med Hyg, 2016 Feb;94(2):336-339.
    PMID: 26598573 DOI: 10.4269/ajtmh.15-0569
    The lack of rapid, affordable, and accurate diagnostic tests represents the primary hurdle affecting malaria surveillance in resource- and expertise-limited areas. Loop-mediated isothermal amplification (LAMP) is a sensitive, rapid, and cheap diagnostic method. Five species-specific LAMP assays were developed based on 18S rRNA gene. Sensitivity and specificity of LAMP results were calculated as compared with microscopic examination and nested polymerase chain reaction. LAMP reactions were highly sensitive with the detection limit of one copy for Plasmodium vivax, Plasmodium falciparum, and Plasmodium malariae and 10 copies for Plasmodium knowlesi and Plasmodium ovale. LAMP positively detected all human malaria species in all positive samples (N = 134; sensitivity = 100%) within 35 minutes. All negative samples were not amplified by LAMP (N = 67; specificity = 100%). LAMP successfully detected two samples with very low parasitemia. LAMP may offer a rapid, simple, and reliable test for the diagnosis of malaria in areas where malaria is prevalent.
    Matched MeSH terms: RNA, Ribosomal, 18S/genetics
  19. Description of raabeia, synactinomyxon and neoactinomyxum developing stages of myxosporeans (Myxozoa) infecting Isochaetides michaelseni Lastočkin (Tubificidae) in Lake Balaton and Kis-Balaton Water Reservoir, Hungary
    Borkhanuddin MH, Cech G, Molnár K, Németh S, Székely C
    Syst Parasitol, 2014 Jul;88(3):245-59.
    PMID: 24935127 DOI: 10.1007/s11230-014-9496-1
    Molecular and morphometric investigations were conducted on the actinosporean morphotypes of myxosporeans surveyed in oligochaetes of Lake Balaton and Kis-Balaton Water reservoir. Oligochaetes belonging to the species Isochaetides michaelseni Lastočkin and Branchiura sowerbyi Beddard as well as to the genera Nais Dujardin, Dero Müller and Aeolosoma Ehrenberg were studied during an 18-month period. Actinosporeans were obtained exclusively from I. michaelseni (7,818 specimens) with very low prevalence (0.01-0.06%). Four new actinosporean morphotypes of the collective groups raabeia (2 types), synactinomyxon (1 type) and neoactinomyxum (1 type) were found and described, including the first synactinomyxon collective group from Hungarian biotopes and a new raabeia morphotype. Except for Synactinomyxon type 1, the 18S rDNA analysis revealed that the spores did not match any myxospore entity found in the GenBank.
    Matched MeSH terms: RNA, Ribosomal, 18S/genetics
  20. Fulltext Sarcocystis nesbitti infection in human skeletal muscle: possible transmission from snakes
    Lau YL, Chang PY, Tan CT, Fong MY, Mahmud R, Wong KT
    Am J Trop Med Hyg, 2014 Feb;90(2):361-4.
    PMID: 24420776 DOI: 10.4269/ajtmh.12-0678
    Sarcocystis nesbitti is an intracellular protozoan parasite found as sarcocysts within muscle fibers of intermediate hosts (monkey and baboon). The definitive host is suspected to be the snake. We report two cases from a larger cohort of 89 patients who had fever, headache, and generalized myalgia after a trip to Pangkor Island, Malaysia. Sarcocysts were detected in skeletal muscle biopsy specimens by light and electron microscopy from these two patients. DNA sequencing based on the 18S ribosomal DNA region identified the Sarcocystis species as S. nesbitti. We also identified S. nesbitti sequences in the stools of a snake (Naja naja). Phylogenetic analysis showed that these sequences form a cluster with most of the other known Sarcocystis species for which the snake is a definitive host. We believe these two patients were likely to have symptomatic acute muscular sarcocystosis after S. nesbitti infection that may have originated from snakes.
    Matched MeSH terms: RNA, Ribosomal, 18S/genetics
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