Displaying publications 1 - 20 of 31 in total

Abstract:
Sort:
  1. Development and characteristics of polymer monoliths for advanced LC bioscreening applications: A review
    Acquah C, Moy CKS, Danquah MK, Ongkudon CM
    J Chromatogr B Analyt Technol Biomed Life Sci, 2016 Mar 15;1015-1016:121-134.
    PMID: 26919447 DOI: 10.1016/j.jchromb.2016.02.016
    Biomedical research advances over the past two decades in bioseparation science and engineering have led to the development of new adsorbent systems called monoliths, mostly as stationary supports for liquid chromatography (LC) applications. They are acknowledged to offer better mass transfer hydrodynamics than their particulate counterparts. Also, their architectural and morphological traits can be tailored in situ to meet the hydrodynamic size of molecules which include proteins, pDNA, cells and viral targets. This has enabled their development for a plethora of enhanced bioscreening applications including biosensing, biomolecular purification, concentration and separation, achieved through the introduction of specific functional moieties or ligands (such as triethylamine, N,N-dimethyl-N-dodecylamine, antibodies, enzymes and aptamers) into the molecular architecture of monoliths. Notwithstanding, the application of monoliths presents major material and bioprocess challenges. The relationship between in-process polymerisation characteristics and the physicochemical properties of monolith is critical to optimise chromatographic performance. There is also a need to develop theoretical models for non-invasive analyses and predictions. This review article therefore discusses in-process analytical conditions, functionalisation chemistries and ligands relevant to establish the characteristics of monoliths in order to facilitate a wide range of enhanced bioscreening applications. It gives emphasis to the development of functional polymethacrylate monoliths for microfluidic and preparative scale bio-applications.
    Matched MeSH terms: Viruses/isolation & purification
  2. Fulltext Viral agents of acute respiratory infections in young children in Kuala Lumpur
    Ong SB, Lam KL, Lam SK
    Bull World Health Organ, 1982;60(1):137-40.
    PMID: 6282479
    The results of this study indicate that the important viral agents associated with lower respiratory tract infections in young children are respiratory syncytial virus, rhinovirus, and parainfluenza virus, particularly in those under 2 years of age. This is in close agreement with studies done in temperate climates. Influenza A virus is seasonal and plays an important role in upper respiratory tract infections in older children.
    Study site: Inpatients and outpatients, University Malaya Medical Centre (UMMC), Kuala Lumpur, Malaysia
    Matched MeSH terms: Respiratory Syncytial Viruses/isolation & purification; Viruses/isolation & purification*
  3. Plaque formation in vero cell cultures by some Malaysian viruses
    Rudnick A, Dewey RW
    Southeast Asian J. Trop. Med. Public Health, 1973 Jun;4(2):272-3.
    PMID: 4201359
    Matched MeSH terms: Insect Viruses/isolation & purification; Viruses/isolation & purification
  4. A new cell culture tube in diagnostic virology for virus isolation
    Chua KB, Chua KH, Chua IL, Chen KF
    Malays J Pathol, 2004 Jun;26(1):69-71.
    PMID: 16190110
    Virus isolation and accurate characterization plays a crucial role in the rapid identification of the causative agents of infectious disease outbreaks especially if the causative viruses are novel where no pre-existing diagnostic reagents would be available. A new cell culture tube, named Jui Meng (JM) Cell Culture Tube, was developed to reduce the cost and improve the efficiency and biosafety of work pertaining to virus isolation. The design of the tube is based heavily on the principle of practicability, functionality, biosafety and long-term cost saving for diagnostic laboratory work in virus isolation. It is designed to culture an initial inoculum of one milliliter of culture medium containing 1 x 10(4) to 1 x 10(5) cells/ml.
    Matched MeSH terms: Viruses/isolation & purification*
  5. Fulltext In situ hybridisation: principles and applications
    Looi LM, Cheah PL
    Malays J Pathol, 1992 Dec;14(2):69-76.
    PMID: 1304627
    In situ hybridisation (ISH) is based on the complementary pairing of labelled DNA or RNA probes with normal or abnormal nucleic acid sequences in intact chromosomes, cells or tissue sections. Compared with other molecular biology techniques applicable to anatomical pathology, ISH enjoys better rapport with histopathologists because of its similarity to immunohistochemistry. It has the unique advantage over other molecular biology techniques--largely based on probe hybridisation with nucleic acid extracted from homogenised tissue samples--of allowing localisation and visualisation of target nucleic acid sequences within morphologically identifiable cells or cellular structures. Probes for ISH may bear radioactive or non-radioactive labels. Isotopic probes (3H, 32P, 35S, 125I) are generally more sensitive than non-isotopic ones but are less stable, require longer processing times and stringent disposal methods. Numerous non-isotopic labels have been used; of these biotin and digoxigenin are the reporters of choice. Optimised non-isotopic systems of equivalent sensitivity to those which use radioactive-labelled probes have been described. In ISH, finding the optimal balance between good morphological preservation of cells and strong hybridisation signals is crucial. Tissue fixation and retention of cytoskeletal structures, unfortunately, impede diffusion of probes into tissues. ISH sensitivity is also influenced by inherent properties of the probe and hybridisation conditions. Although ISH is largely a research tool, it is already making strong inroads into diagnostic histopathology. It has been applied for the detection of various infective agents particularly CMV, HPV, HIV, JC virus, B19 parvovirus, HSV-1, EBV, HBV, hepatitis delta virus, Chlamydia trachomatis, salmonella and mycoplasma in tissue sections.(ABSTRACT TRUNCATED AT 250 WORDS)
    Matched MeSH terms: Viruses/isolation & purification*
  6. Fulltext Detection of Laem-Singh virus in cultured Penaeus monodon shrimp from several sites in the Indo-Pacific region
    Sittidilokratna N, Dangtip S, Sritunyalucksana K, Babu R, Pradeep B, Mohan CV, et al.
    Dis Aquat Organ, 2009 Apr 27;84(3):195-200.
    PMID: 19565696 DOI: 10.3354/dao02059
    Laem-Singh virus (LSNV) is a positive-sense single-stranded RNA (ssRNA) virus that was recently identified in Penaeus monodon shrimp in Thailand displaying signs of slow growth syndrome. A total of 326 shrimp collected between 1998 and 2007 from countries in the Indo-Pacific region were tested by RT-PCR for evidence of LSNV infection. The samples comprised batches of whole postlarvae, and lymphoid organ, gill, muscle or pleopod tissue of juvenile, subadult and adult shrimp. LSNV was not detected in 96 P. monodon, P. japonicus or P. merguiensis from Australia or 16 P. monodon from Fiji, Philippines, Sri Lanka and Mozambique. There was no evidence of LSNV infection in 73 healthy juvenile P. vannamei collected during 2006 from ponds at 9 locations in Thailand. However, LNSV was detected in each of 6 healthy P. monodon tested from Malaysia and Indonesia, 2 of 6 healthy P. monodon tested from Vietnam and 39 of 40 P. monodon collected from slow-growth ponds in Thailand. A survey of 81 P. monodon collected in 2007 from Andhra Pradesh, India, indicated 56.8% prevalence of LSNV infection but no clear association with disease or slow growth. Phylogenetic analysis of PCR amplicons obtained from samples from India, Vietnam, Malaysia and Thailand indicated that nucleotide sequence variation was very low (>98% identity) and there was no clustering of viruses according to site of isolation or the health status of the shrimp. The data suggests that LSNV exists as a single genetic lineage and occurs commonly in healthy P. monodon in parts of Asia.
    Matched MeSH terms: RNA Viruses/isolation & purification*
  7. Fulltext Contaminating viral sequences in high-throughput sequencing viromics: a linkage study of 700 sequencing libraries
    Asplund M, Kjartansdóttir KR, Mollerup S, Vinner L, Fridholm H, Herrera JAR, et al.
    Clin Microbiol Infect, 2019 Oct;25(10):1277-1285.
    PMID: 31059795 DOI: 10.1016/j.cmi.2019.04.028
    OBJECTIVES: Sample preparation for high-throughput sequencing (HTS) includes treatment with various laboratory components, potentially carrying viral nucleic acids, the extent of which has not been thoroughly investigated. Our aim was to systematically examine a diverse repertoire of laboratory components used to prepare samples for HTS in order to identify contaminating viral sequences.

    METHODS: A total of 322 samples of mainly human origin were analysed using eight protocols, applying a wide variety of laboratory components. Several samples (60% of human specimens) were processed using different protocols. In total, 712 sequencing libraries were investigated for viral sequence contamination.

    RESULTS: Among sequences showing similarity to viruses, 493 were significantly associated with the use of laboratory components. Each of these viral sequences had sporadic appearance, only being identified in a subset of the samples treated with the linked laboratory component, and some were not identified in the non-template control samples. Remarkably, more than 65% of all viral sequences identified were within viral clusters linked to the use of laboratory components.

    CONCLUSIONS: We show that high prevalence of contaminating viral sequences can be expected in HTS-based virome data and provide an extensive list of novel contaminating viral sequences that can be used for evaluation of viral findings in future virome and metagenome studies. Moreover, we show that detection can be problematic due to stochastic appearance and limited non-template controls. Although the exact origin of these viral sequences requires further research, our results support laboratory-component-linked viral sequence contamination of both biological and synthetic origin.

    Matched MeSH terms: Viruses/isolation & purification*
  8. Arbovirus infections in Sarawak: further observations on mosquitoes
    Macdonald WW, Smith CE, Dawson PS, Ganapathipillai A, Mahadevan S
    J Med Entomol, 1967 May;4(2):146-57.
    PMID: 4383192
    Matched MeSH terms: Encephalitis Viruses/isolation & purification*
  9. Lanjan virus, a new agent isolated from Dermacentor auratus in Malaya
    Tan DS, Smith CE, McMahon DA, Bowen ET
    Nature, 1967 Jun 10;214(5093):1154-5.
    PMID: 4964058
    Matched MeSH terms: Insect Viruses/isolation & purification*
  10. Fulltext Viral persistence in colorectal cancer cells infected by Newcastle disease virus
    Chia SL, Yusoff K, Shafee N
    Virol J, 2014 May 16;11:91.
    PMID: 24886301 DOI: 10.1186/1743-422X-11-91
    BACKGROUND: Newcastle disease virus (NDV), a single-stranded RNA virus of the family Paramyxoviridae, is a candidate virotherapy agent in cancer treatment. Promising responses were observed in clinical studies. Despite its high potential, the possibility of the virus to develop a persistent form of infection in cancer cells has not been investigated. Occurrence of persistent infection by NDV in cancer cells may cause the cells to be less susceptible to the virus killing. This would give rise to a population of cancer cells that remains viable and resistant to treatment.

    RESULTS: During infection experiment in a series of colorectal cancer cell lines, we adventitiously observed a development of persistent infection by NDV in SW480 cells, but not in other cell lines tested. This cell population, designated as SW480P, showed resistancy towards NDV killing in a re-infection experiment. The SW480P cells retained NDV genome and produced virus progeny with reduced plaque forming ability.

    CONCLUSION: These observations showed that NDV could develop persistent infection in cancer cells and this factor needs to be taken into consideration when using NDV in clinical settings.

    Matched MeSH terms: Oncolytic Viruses/isolation & purification
  11. Immunological characterization of rice tungro spherical virus coat proteins and differentiation of isolates from the Philippines and India
    Druka A, Burns T, Zhang S, Hull R
    J Gen Virol, 1996 Aug;77 ( Pt 8):1975-83.
    PMID: 8760450
    Rice tungro spherical virus (RTSV) has an RNA genome of more than 12 kb with various features which classify it as a plant picornavirus. The capsid comprises three coat protein (CP) species, CP1, CP2 and CP3, with predicted molecular masses of 22.5, 22.0 and 33 kDa, respectively, which are cleaved from a polyprotein. In order to obtain information on the properties of these proteins, each was expressed in E. coli, purified as a fusion to the maltose-binding protein and used for raising a polyclonal antiserum. CP1, CP2 and CP3 with the expected molecular masses were detected specifically in virus preparations. CP3 is probably the major antigenic determinant on the surface of RTSV particles, as was shown by ELISA, Western blotting and immunogold electron microscopy using antisera obtained against whole virus particles and to each CP separately. In some cases, especially in crude extracts, CP3 antiserum detected several other proteins (40-42 kDa), which could be products of CP3 post-translational modification. No serological differences were detected between the three CPs from isolates from the Philippines, Thailand, Malaysia and India. The CP3-related 40-42 kDa proteins of the Indian RTSV isolate have a slightly higher electrophoretic mobility (42-44 kDa) and a different response to cellulolytic enzyme preparations, which allows them to be differentiated from south-east Asian isolates.
    Matched MeSH terms: Plant Viruses/isolation & purification; RNA Viruses/isolation & purification
  12. Membrane separations
    Walter JK, Jin Z, Jornitz MW, Gorrschalk U
    Methods Biochem Anal, 2011;54:281-317.
    PMID: 21954783
    Matched MeSH terms: Viruses/isolation & purification
  13. Fulltext New virus is identified in Malaysia epidemic
    Easton A
    BMJ, 1999 May 08;318(7193):1232.
    PMID: 10231244
    Matched MeSH terms: Encephalitis Viruses/isolation & purification
  14. Sequences of the three coat protein genes of a Malaysian isolate of rice tungro spherical virus reveal a close relationship to the Philippine isolate
    Zhang S, Davies JW, Hull R
    Virus Genes, 1997;15(1):61-4.
    PMID: 9354271
    Coat protein genes CP1, CP2 and CP3 of an isolate (MaP1) of rice tungro spherical virus (RTSV) from Malaysia were isolated, cloned and sequenced. Comparative analysis indicated that MaP1 isolate is closely related to the Philippine isolate.
    Matched MeSH terms: Plant Viruses/isolation & purification
  15. Fulltext Respiratory viruses detected in hospitalised paediatric patients with respiratory infections
    Zamberi S, Zulkifli I, Ilina I
    Med J Malaysia, 2003 Dec;58(5):681-7.
    PMID: 15190654 MyJurnal
    Over 200 strains of respiratory viruses cause a variety of human infections ranging from common cold to life-threatening pneumonia. Respiratory viruses implicated in this study are respiratory syncytial viruses (RSV), adenovirus, influenza viruses and parainfluenza viruses. The objective of this study is to determine the epidemiology of respiratory viruses in paediatric patients with lower respiratory tract infection. The methods used were direct antigen detection method, shell vial culture method and conventional tube culture method. The samples included in this study are paediatric patients seen in Universiti Kebangsaan Malaysia Hospital, Kuala Lumpur with suspected acute viral respiratory infection, presenting with acute laryngotracheobronchitis (croup), bronchiolitis and pneumonia. Nasopharyngeal aspirates were collected and processed almost immediately. A total of 222 specimens were received during February 1999 to January 2000 showing a dual peak pattern in the months of April and December. The mean age of the patients was 13 months. Pneumonia (77.9%) was the most common clinical diagnosis in children with lower respiratory tract infection. This was followed by bronchiolitis (19.4%) and croup (27%). Viral aetiologies were confirmed in 23.4% of the patients. The most common respiratory virus isolated or detected was RSV, followed by parainfluenza viruses, influenza viruses and adenovirus.
    Matched MeSH terms: Respiratory Syncytial Viruses/isolation & purification
  16. Japanese B encephalitis in a horse
    Chong Sue Kheng, Teoh Kim Chee, Marchette NJ, Garcia R, Rudnick A, Coughlan RF
    Aust. Vet. J., 1968 Jan;44(1):23-5.
    PMID: 5689238
    Matched MeSH terms: Encephalitis Viruses/isolation & purification
  17. [Emergence of new viruses in Asia: is climate change involved?]
    Chastel C
    Med Mal Infect, 2004 Nov;34(11):499-505.
    PMID: 15620053
    Tropical Africa is not the only area where deadly viruses have recently emerged. In South-East Asia severe epidemics of dengue hemorrhagic fever started in 1954 and flu pandemics have originated from China such as the Asian flu (H2N2) in 1957, the Hong-Kong flu (H3N2) in 1968, and the Russian flu (H1N1) in 1977. However, it is especially during the last ten years that very dangerous viruses for mankind have repeatedly developed in Asia, with the occurrence of Alkhurma hemorrhagic fever in Saudi Arabia (1995), avian flu (H5N1) in Hong-Kong (1997), Nipah virus encephalitis in Malaysia (1998,) and, above all, the SARS pandemic fever from Southern China (2002). The evolution of these viral diseases was probably not directly affected by climate change. In fact, their emergential success may be better explained by the development of large industry poultry flocks increasing the risks of epizootics, dietary habits, economic and demographic constraints, and negligence in the surveillance and reporting of the first cases.
    Matched MeSH terms: Viruses/isolation & purification*
  18. Isolation and Quantification of Mimivirus-Like and Marseillevirus-Like Viruses from Soil Samples in An Aboriginal (Orang asli) Village in Peninsular Malaysia
    Tan YF, Lim CY, Chong CW, Lim PKC, Yap IKS, Leong PP, et al.
    Intervirology, 2018;61(2):92-95.
    PMID: 30121676 DOI: 10.1159/000491602
    BACKGROUND: The giant amoebal viruses of Mimivirus and Marseillevirus are large DNA viruses and have been documented in water, soil, and sewage samples. The trend of discovering these giant amoebal viruses has been increasing throughout Asia with Japan, India, and Saudi Arabia being the latest countries to document the presence of these viruses. To date, there have been no reports of large amoebal viruses being isolated in South East Asia.

    OBJECTIVE: In this study, we aim to discover these viruses from soil samples in an aboriginal village (Serendah village) in Peninsular -Malaysia.

    METHOD AND RESULTS: We successfully detected and isolated both Mimivirus-like and Marseillevirus-like viruses using Acanthamoeba castellanii. Phylogeny analysis identified them as Mimivirus and Marseillevirus, respectively.

    CONCLUSION: The ubiquitous nature of both Mimivirus and Marseillevirus is further confirmed in our study as they are detected in higher quantity in soil that is near to water vicinities in an aboriginal village in Peninsular Malaysia. However, this study is limited by our inability to investigate the impact of Mimivirus and Marseillevirus on the aboriginal villagers. More studies on the potential impact of these viruses on human health, especially on the aborigines, are warranted.

    Matched MeSH terms: DNA Viruses/isolation & purification
  19. Fulltext Isolation and Identification of Inter-Species Enterovirus Recombinant Genomes
    Bentley K, Tee HK, Pearson A, Lowry K, Waugh S, Jones S, et al.
    Viruses, 2021 11 29;13(12).
    PMID: 34960659 DOI: 10.3390/v13122390
    Positive-strand RNA virus evolution is partly attributed to the process of recombination. Although common between closely genetically related viruses, such as within species of the Enterovirus genus of the Picornaviridae family, inter-species recombination is rarely observed in nature. Recent studies have shown recombination is a ubiquitous process, resulting in a wide range of recombinant genomes and progeny viruses. While not all recombinant genomes yield infectious progeny virus, their existence and continued evolution during replication have critical implications for the evolution of the virus population. In this study, we utilised an in vitro recombination assay to demonstrate inter-species recombination events between viruses from four enterovirus species, A-D. We show that inter-species recombinant genomes are generated in vitro with polymerase template-switching events occurring within the virus polyprotein coding region. However, these genomes did not yield infectious progeny virus. Analysis and attempted recovery of a constructed recombinant cDNA revealed a restriction in positive-strand but not negative-strand RNA synthesis, indicating a significant block in replication. This study demonstrates the propensity for inter-species recombination at the genome level but suggests that significant sequence plasticity would be required in order to overcome blocks in the virus life cycle and allow for the production of infectious viruses.
    Matched MeSH terms: Reassortant Viruses/isolation & purification
  20. Fulltext Discovery of Known and Novel Viruses in Wild and Cultivated Blueberry in Florida through Viral Metagenomic Approaches
    Saad N, Olmstead JW, Varsani A, Polston JE, Jones JB, Folimonova SY, et al.
    Viruses, 2021 Jun 18;13(6).
    PMID: 34207047 DOI: 10.3390/v13061165
    Southern highbush blueberry (interspecific hybrids of Vaccinium corymbosum L.) is cultivated near wild V. corymbosum as well as closely related species in Florida, USA. The expansion of blueberry cultivation into new areas in Florida and deployment of new cultivars containing viruses can potentially increase the diversity of viruses in wild and cultivated V. corymbosum. In this study, viral diversity in wild and cultivated blueberries (V. corymbosum) is described using a metagenomic approach. RNA viromes from V. corymbosum plants collected from six locations (two cultivated and four wild) in North Central Florida were generated by high throughput sequencing (HTS) and analyzed using a bioinformatic analysis pipeline. De novo assembled contigs obtained from viromes of both commercial and wild sites produced sequences with similarities to plant virus species from a diverse range of families (Amalgaviridae, Caulimoviridae, Endornaviridae, Ophioviridae, Phenuiviridae, and Virgaviridae). In addition, this study has enabled the identification of blueberry latent virus (BlLV) and blueberry mosaic associated ophiovirus (BlMaV) for the first time in Florida, as well as a tentative novel tepovirus (blueberry virus T) (BlVT) in blueberry. To the best of our knowledge, this is the first study that compares viral diversity in wild and cultivated blueberry using a metagenomic approach.
    Matched MeSH terms: Plant Viruses/isolation & purification*
Related Terms
Filters
Contact Us

Please provide feedback to Administrator (afdal@afpm.org.my)

External Links