Displaying publications 41 - 60 of 67 in total

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  1. Solubility, immunogenicity and physical properties of the nucleocapsid protein of Nipah virus produced in Escherichia coli
    Tan WS, Ong ST, Eshaghi M, Foo SS, Yusoff K
    J Med Virol, 2004 May;73(1):105-12.
    PMID: 15042656
    The nucleocapsid (N) protein of Nipah virus (NiV) can be produced in three Escherichia coli strains [TOP10, BL21(DE3) and SG935] under the control of trc promoter. However, most of the product existed in the form of insoluble inclusion bodies. There was no improvement in the solubility of the product when this protein was placed under the control of T7 promoter. However, the solubility of the N protein was significantly improved by lowering the growth temperature of E. coli BL21(DE3) cell cultures. Solubility analysis of N- and C-terminally deleted mutants revealed that the full-length N protein has the highest solubility. The soluble N protein could be purified efficiently by sucrose gradient centrifugation and nickel affinity chromatography. Electron microscopic analysis of the purified product revealed that the N protein assembled into herringbone-like particles of different lengths. The C-terminal end of the N protein contains the major antigenic region when probed with antisera from humans and pigs infected naturally.
    Matched MeSH terms: DNA, Viral/genetics
  2. Cloning and expression of the phosphoprotein gene of Newcastle disease virus in Escherichia coli
    Kho CL, Tan WS, Yusoff K
    J. Biochem. Mol. Biol. Biophys., 2002 Apr;6(2):117-21.
    PMID: 12186767
    The phosphoprotein (P) gene of a heat stable Newcastle disease virus (NDV) was cloned, sequenced and expressed in Escherichia coli. SDS-PAGE analysis of the recombinant P protein (395 amino acids) and a C-terminal extension derivative (424 amino acids), gave rise to two distinct protein bands with molecular masses of approximately 53-55 and 56-58 kDa, respectively, which are approximately 26-30% heavier than those calculated from the deduced amino acid sequences. The differences in molecular mass on SDS-PAGE are thought to be attributed to the acidic nature of the P protein (pI=6.27) and also the different degrees of phosphorylation in the prokaryotic cell. Amino acid sequence comparison of the P protein among the published NDV strains showed that they were highly conserved particularly at the putative phosphorylation sites.
    Matched MeSH terms: DNA, Viral/genetics
  3. Sequence and phylogenetic analysis of the VP2 gene of very virulent infectious bursal disease virus isolates
    Hoque MM, Omar AR, Hair-Bejo M, Aini I
    J. Biochem. Mol. Biol. Biophys., 2002 Apr;6(2):93-9.
    PMID: 12186763
    Previously we have shown that very virulent infectious bursal disease viruses (vvIBDV) that are SspI, TaqI and StyI positive (92/04, 97/61 and 94/B551) but not SspI and TaqI positive and StyI negative (94/273) cause high mortality, up to 80% in specific-pathogen-free chickens with significant damage of the bursal as well as nonbursal tissues. In this study, we sequenced the VP2 gene (1351 bp) of the 92/04, 94/273 and 94/B551 and compared them with other IBDV strains. All the isolates have the unique amino acid residues at positions 222A, 256I, 294I and 299S found in other vvIBDV strains. The deduced VP2 amino acids encoded by 92/04 is identical to the vvIBDV strains from Israel (IBDVKS), Japan (OKYM) and Europe (UK661), whereas the 94/273 and 94/B551 isolates have one to three amino acid substitutions. The 94/273 has two amino acid substitutions at positions 254 G to S and at 270 A to E that have not been reported before from vvIBDV strains. The 94/B551 also has one amino acid substitution at position 300 E to S, which is uncommon among other vvIBDV strains. However, phylogenetic analysis suggested that the isolates are very close to each other and all of them may have derived from the same origin as vvIBDV strains isolated from China, Japan and Europe. Even though antigenic index analysis of the 94/273 and 94/B551 indicated that the isolates are unique compared to other IBDV strains, their antigenic variation remain to be determined by monoclonal antibody study.
    Matched MeSH terms: DNA, Viral/genetics
  4. Genomic variations among wildtype and mutant strains of pseudorabies virus
    Zeenathul NA, Mohd-Azmi ML, Ali AS, Aini I, Sheik-Omar AR, Abdul-Rahim AM, et al.
    Rev. Argent. Microbiol., 2002 Jan-Mar;34(1):7-14.
    PMID: 11942085
    Both wild-type virulent and mutant strains of pseudorabies virus (PrV) were used in this study. Mutants used were derived from the plaque purified strain PrVmAIP. A total of six drug resistant mutants, three bromodeoxyuridine (BUdR) resistant and three iododeoxyuridine (IUdR) resistant, respectively, were isolated and passaged in chicken embryo fibroblast (CEF) cells. The DNA of these PrVs were compared with the wild-type isolates by means of the restriction fragment pattern (RFP) findings produced with Bam HI, Kpn I, Hind III and Bgl II restriction enzymes (RE). Compared to the wild-type PrVs (PrV-VBA1-parental strain of PrVmAIP; PrV-VBA2; PrV-VBA3), the RFP of PrVmAIP showed the presence of mutations within the RE sites studied. Both PrV-VBA1 and PrV-VBA2 appeared to be closely related but their RFPs differed from PrV-VBA3. Significant differences either in the number, size or migrations of the DNA fragments could also be detected in the BUdR resistant strains. Even though different features of cytopathic effect (GPE) were observed in the IUdR resistant PrVs, the RFP findings remained identical. The PrVs studied showed considerable differences from the reference PrV (PrV-CD).
    Matched MeSH terms: DNA, Viral/genetics*
  5. Feline leukemia virus in owned cats in Southeast Asia and Taiwan
    Capozza P, Lorusso E, Colella V, Thibault JC, Tan DY, Tronel JP, et al.
    Vet Microbiol, 2021 Mar;254:109008.
    PMID: 33582484 DOI: 10.1016/j.vetmic.2021.109008
    Feline leukaemia virus (FeLV) is a retrovirus associated with fatal disease in cats with infection in its progressive form. Although there are numerous reports on the occurrence of FeLV in the feline population worldwide, there is a paucity of data in Asia. In this study, we assessed the circulation of FeLV by ELISA and nested PCR in cats from different countries in Southeast Asia (i.e., Thailand, Malaysia, Singapore, Philippines, Indonesia and Vietnam) and Taiwan during 2017-2018. Forty-seven cats were positive to FeLV by antigen or provirus detection, but 32 samples were considered truly positive on the basis of positive molecular testing. Frequency of occurrence of FeLV proviral DNA ranged from 0% (0/43 positive samples) in Indonesia to 18.5% (22/119 positive samples) in Thailand. A statistically significant association (p < 0.05) was found between country of cats origin, age, lifestyle, abnormal oral mucosa, and FeLV molecular positive results. In-depth studies are needed in other countries in Southeast Asia to elucidate the mosaic of knowledge about FeLV epidemiology.
    Matched MeSH terms: DNA, Viral/genetics
  6. Fulltext Co-administration of avian influenza virus H5 plasmid DNA with chicken IL-15 and IL-18 enhanced chickens immune responses
    Lim KL, Jazayeri SD, Yeap SK, Alitheen NB, Bejo MH, Ideris A, et al.
    BMC Vet Res, 2012;8:132.
    PMID: 22866758 DOI: 10.1186/1746-6148-8-132
    DNA vaccines offer several advantages over conventional vaccines in the development of effective vaccines against avian influenza virus (AIV). However, one of the limitations of the DNA vaccine in poultry is that it induces poor immune responses. In this study, chicken interleukin (IL) -15 and IL-18 were used as genetic adjuvants to improve the immune responses induced from the H5 DNA vaccination in chickens. The immunogenicity of the recombinant plasmid DNA was analyzed based on the antibody production, T cell responses and cytokine production, following inoculation in 1-day-old (Trial 1) and 14-day-old (Trial 2) specific-pathogen-free chickens. Hence, the purpose of the present study was to explore the role of chicken IL-15 and IL-18 as adjuvants following the vaccination of chickens with the H5 DNA vaccine.
    Matched MeSH terms: DNA, Viral/genetics
  7. Detection of human papillomavirus DNA in routine cervical scraping samples: use for a national cervical cancer screening program in a developing nation
    Othman N, Othman NH
    Asian Pac J Cancer Prev, 2014;15(5):2245-9.
    PMID: 24716964
    BACKGROUND: Human papillomavirus is a well-established cause of the development of a variety of epithelial lesions in the cervix. However, as yet, incorporation of HPV testing into cervical cancer screening either as an adjunct or stand alone test is limited due to its cost. We therefore here ascertained the presence and type specificity of human papilloma virus (HPV) DNA in routine cervical scrapings.

    MATERIALS AND METHODS: Cervical scrapings were collected from women attending clinics for routine Pap smear screening. HPV-DNA was detected by PCR using MY09/11 and GP5+/GP6+ primer sets and genotyping was accomplished by cycle-sequencing.

    RESULTS: A total of 635 women were recruited into the study with mean ± SD age of 43 ± 10.5 years. Of these 92.6% (588/635) were reported as within normal limits (WNL) on cytology. The presence of HPV infection detected by nested MY/GP+-PCR was 4.4% (28/635). The overall prevalence of high-risk HPV (HR-HPV) in abnormal Pap smears was 53.8% (7/13). HPVs were also seen in 3.1% (18/588) of smears reported as WNL by cytology and 5.9% (2/34) in smears unsatisfactory for evaluation.

    CONCLUSIONS: The overall percentage of HPV positivity in routine cervical screening samples is comparable with abnormal findings in cytology. Conventional Pap smear 'missed' a few samples. Since HPV testing is expensive, our results may provide valuable information for strategising implementation of effective cervical cancer screening in a country with limited resources like Malaysia. If Pap smear coverage could be improved, HPV testing could be used as an adjunct method on cases with ambiguous diagnoses.

    Matched MeSH terms: DNA, Viral/genetics*
  8. Fulltext Identification of a novel Getah virus by Virus-Discovery-cDNA random amplified polymorphic DNA (RAPD)
    Hu T, Zheng Y, Zhang Y, Li G, Qiu W, Yu J, et al.
    BMC Microbiol, 2012;12:305.
    PMID: 23268691 DOI: 10.1186/1471-2180-12-305
    The identification of new virus strains is important for the study of infectious disease, but current (or existing) molecular biology methods are limited since the target sequence must be known to design genome-specific PCR primers. Thus, we developed a new method for the discovery of unknown viruses based on the cDNA--random amplified polymorphic DNA (cDNA-RAPD) technique. Getah virus, belonging to the family Togaviridae in the genus Alphavirus, is a mosquito-borne enveloped RNA virus that was identified using the Virus-Discovery-cDNA RAPD (VIDISCR) method.
    Matched MeSH terms: DNA, Viral/genetics
  9. Fulltext Detection and characterization of chicken anemia virus from commercial broiler breeder chickens
    Hailemariam Z, Omar AR, Hair-Bejo M, Giap TC
    Virol J, 2008;5:128.
    PMID: 18954433 DOI: 10.1186/1743-422X-5-128
    Chicken anemia virus (CAV) is the causative agent of chicken infectious anemia (CIA). Study on the type of CAV isolates present and their genetic diversity, transmission to their progeny and level of protection afforded in the breeder farms is lacking in Malaysia. Hence, the present study was aimed to detect CAV from commercial broiler breeder farms and characterize CAV positive samples based on sequence and phylogenetic analysis of partial VP1 gene.
    Matched MeSH terms: DNA, Viral/genetics
  10. High-titred neutralizing antibodies to human enterovirus 71 preferentially bind to the N-terminal portion of the capsid protein VP1
    Tan CS, Cardosa MJ
    Arch Virol, 2007;152(6):1069-73.
    PMID: 17318736
    Human enterovirus 71 has emerged as an important pathogen of children in the Asia Pacific region, and it may be important to consider the development of a vaccine against this virus. Human cord serum was used as a source of neutralizing antibodies to determine whether the N- or C-terminal half of the VP1 capsid protein was more likely to harbour neutralizing determinants. Cord sera from 205 individuals were tested for neutralizing antibodies against human enterovirus 71 in an indirect ELISA against recombinant VP1 antigen as well as the N- and C-terminal portions of VP1 antigen. High-titred human neutralizing antibodies were significantly more reactive with the N-terminal half of VP1 than weak or negative sera. The N-terminal half of human enterovirus 71 is likely to have important neutralizing antibody determinants and should be investigated further in vaccine development efforts.
    Matched MeSH terms: DNA, Viral/genetics
  11. Combined use of wild-type HBV precore and high serum iron marker as a potential tool for the prediction of cirrhosis in chronic hepatitis B infection
    Chook JB, Ngeow YF, Yap SF, Tan TC, Mohamed R
    J Med Virol, 2011 Apr;83(4):594-601.
    PMID: 21328372 DOI: 10.1002/jmv.22016
    Hepatitis B virus (HBV) and high liver iron deposits have both been associated with the development of cirrhosis. Among HBV factors, genotype and mutations in the basal core promoter (BCP) and precore regions have been most frequently studied but the evidence for a positive association with cirrhosis has been inconsistent. In this study, sera from persons with chronic HBV infection with and without cirrhosis were used for whole HBV genome analysis and for the estimation of serum iron marker (serum iron or ferritin) levels. Single codon analysis showed that the precore wild-type, TGG (nt 1,895-1,897), gave the highest accuracy (77.5%) for the identification of cirrhosis compared to other codons. When TGG was analyzed together with the precore start codon wild-type, ATG (nt 1,814-1,816), the accuracy was improved to 80.0% (odds ratio=35.29; 95% confidence interval=3.87-321.93; Phi=0.629; P<0.001). When the serum iron marker was included for analysis, it was clear that a combination of a precore wild-type and high serum iron marker gave a better accuracy (90.0%) (odds ratio=107.67; 95% confidence interval=10.21-1,135.59; Phi=0.804; P<0.001) for the identification of cirrhosis than either biomarker alone. It appeared that a combined use of both these biomarkers might help to predict the development of cirrhosis in a person with chronic HBV infection, but longitudinal studies are required to test this hypothesis.
    Matched MeSH terms: DNA, Viral/genetics
  12. Fulltext Genetic characterization of porcine circovirus 2 found in Malaysia
    Jaganathan S, Toung OP, Yee PL, Yew TD, Yoon CP, Keong LB
    Virol J, 2011;8:437.
    PMID: 21914166 DOI: 10.1186/1743-422X-8-437
    Porcine circovirus type 2 is the primary etiological agent associated with a group of complex multi-factorial diseases classified as Porcine Circovirus Associated Diseases (PCVAD). Sporadic cases reported in Malaysia in 2007 caused major economic losses to the 2.2 billion Malaysian ringgit (MYR) (approximately 0.7 billion US dollar) swine industry. The objective of the present study was to determine the association between the presence of PCV2 and occurrences of PCVAD.
    Matched MeSH terms: DNA, Viral/genetics
  13. White spot syndrome virus isolates of tiger shrimp Penaeus monodon (Fabricious) in India are similar to exotic isolates as revealed by polymerase chain reaction and electron microscopy
    Mishra SS, Shekhar MS
    Indian J Exp Biol, 2005 Jul;43(7):654-61.
    PMID: 16053274
    Microbiological analysis of samples collected from cases of white spot disease outbreaks in cultured shrimp in different farms located in three regions along East Coast of India viz. Chidambram (Tamil Nadu), Nellore (Andhra Pradesh) and Balasore (Orissa), revealed presence of Vibrio alginolyticus, Vibrio parahaemolyticus, and Aeromonas spp. but experimental infection trials in Penaeus monodon with these isolates did not induce any acute mortality or formation of white spots on carapace. Infection trials using filtered tissue extracts by oral and injection method induced mortality in healthy P. monodon with all samples and 100% mortality was noted by the end of 7 day post-inoculation. Histopathological analysis demonstrated degenerated cells characterized by hypertrophied nuclei in gills, hepatopancreas and lymphoid organ with presence of intranuclear basophilic or eosino-basophilic bodies in tubular cells and intercellular spaces. Analysis of samples using 3 different primer sets as used by other for detection of white spot syndrome virus (WSSV) generated 643, 1447 and 520bp amplified DNA products in all samples except in one instance. Variable size virions with mean size in the range of 110 x 320 +/- 20 nm were observed under electron microscope. It could be concluded that the viral isolates in India involved with white spot syndrome in cultured shrimp are similar to RV-PJ and SEMBV in Japan, WSBV in Taiwan and WSSV in Malaysia, Indonesia, Thailand, China and Japan.
    Matched MeSH terms: DNA, Viral/genetics
  14. Comparative analysis of viral RNA and apoptotic cells in bursae following infection with infectious bursal disease virus
    Kong LL, Omar AR, Hair-Bejo M, Aini I, Seow HF
    Comp Immunol Microbiol Infect Dis, 2004 Nov;27(6):433-43.
    PMID: 15325516
    Specific-pathogen-free (SPF) chickens infected with very virulent (vv) infectious bursal disease virus (IBDV) UPM94/273 developed lower pathogenicity compared to UPM97/61. Sequence analysis indicated that UPM94/273 is an exceptional vvIBDV. In this study, a SYBR Green I based real-time reverse transcriptase reaction assay was developed to measure viral RNA in the bursae of SPF chickens infected with IBDV. Specificity of the amplified products was confirmed by melting temperature analysis. A linear relationship was observed between the amount of input viral RNA and the threshold values for IBDV-specific product over five log10 dilutions. The viral RNA level following infection with UPM94/273 was significantly higher at day 1 and 2 post-inoculation (p.i.) compared to UPM97/61 infected chickens. However, chickens infected with UPM97/61 had significantly higher numbers of bursal cells undergoing apoptosis compared to UPM94/273 infected chickens. In both groups, the number of apoptotic cells and viral RNA levels peak at day 3 p.i. This study indicates that UPM97/61 and UPM94/273 have different efficiency of replication and percentage of apoptotic cells in bursae during the acute phase of IBDV infection.
    Matched MeSH terms: DNA, Viral/genetics
  15. Molecular characterization of serotype A foot-and-mouth disease viruses circulating in Vietnam in 2009
    Le VP, Nguyen T, Lee KN, Ko YJ, Lee HS, Nguyen VC, et al.
    Vet Microbiol, 2010 Jul 29;144(1-2):58-66.
    PMID: 20097490 DOI: 10.1016/j.vetmic.2009.12.033
    Foot-and-mouth disease (FMD) is a major cause of endemic outbreaks in Vietnam in recent years. In this work, six serotype A foot-and-mouth disease viruses (FMDV), collected from endemic outbreaks during January and February of 2009 in four different provinces in Vietnam, were genetically characterized for their complete genome sequences. Genetic analysis based on the complete viral genome sequence indicated that they were closely related to each other and shared 99.0-99.8% amino acid (aa) identity. Genetic and deduced aa analysis of the capsid coding gene VP1 showed that the six Vietnamese strains were all classified into the genotype IX from a total of 10 major genotypes worldwide, sharing 98.1-100% aa identity each other. They were most closely related to the type A strains recently isolated in Laos (A/LAO/36/2003, A/LAO/1/2006, A/LAO/6/2006, A/LAO/7/2006, and A/LAO/8/2006), Thailand (A/TAI/2/1997 and A/TAI/118/1987), and Malaysia (A/MAY/2/2002), sharing 88.3-95.5% nucleotide (nt) identities. In contrast, Vietnamese type A strains showed low nt identities with the two old type A FMDVs, isolated in 1960 in Thailand (a15thailand iso43) and in 1975 in the Philippines (aphilippines iso50), ranging from 77.3 to 80.9% nt identity. A multiple alignment based on the deduced amino acid sequences of the capsid VP1 coding gene of type A FMDV revealed three amino acid substitutions between Vietnamese strains and the strains of other Southeast Asian countries (Laos, Thailand, Malaysia, and the Philippines). Alanine was replaced by valine at residue 24, asparagine by arginine at residue 85, and serine by threonine at residue 196. Furthermore, type A FMDV strains recently isolated in Vietnam, Laos, Thailand, and Malaysia all have one amino acid deletion at residue 140 of the capsid VP1 protein compared with the two old type A FMDV strains from Thailand and the Philippines as well as most other type A representatives worldwide. This article is the first to report on the comprehensive genetic characterization of type A FMDV circulating in Vietnam.
    Matched MeSH terms: DNA, Viral/genetics
  16. Fulltext A novel and non-invasive approach utilising nasal washings for the detection of nasopharyngeal carcinoma
    Tan GW, Sivanesan VM, Abdul Rahman FI, Hassan F, Hasbullah HH, Ng CC, et al.
    Int J Cancer, 2019 Oct 15;145(8):2260-2266.
    PMID: 30698824 DOI: 10.1002/ijc.32173
    Nasopharyngeal carcinoma (NPC) is an epithelial cancer of the nasopharynx which is highly associated with Epstein-Barr virus (EBV). Worldwide, most of the top 20 countries with the highest incidence and mortality rates of NPC are low- and middle-income countries. Many studies had demonstrated that EBV could be detected in the tissue, serum and plasma of NPC patients. In this study, we explored the potential of assays based on non-invasive nasal washings (NW) as a diagnostic and prognostic tool for NPC. A total of 128 patients were evaluated for NW EBV DNA loads and a subset of these samples were also tested for 27 EBV and human miRNAs shortlisted from literature. EBV DNA and seven miRNAs showed area under the receiver operating characteristic curve (AUC) values of more than 0.7, suggestive of their potential utility to detect NPC. Logistic regression analyses suggested that combination of two NW assays that test for EBNA-1 and hsa-miR-21 had the best performance in detecting NPC. The trend of NW EBV DNA load matched with clinical outcome of 71.4% (10 out of 14) NPC patients being followed-up. In summary, the non-invasive NW testing panel may be particularly useful for NPC screening in remote areas where healthcare facilities and otolaryngologists are lacking, and may encourage frequent testing of individuals in the high risk groups who are reluctant to have their blood tested. However, further validation in an independent cohort is required to strengthen the utility of this testing panel as a non-invasive detection tool for NPC.
    Matched MeSH terms: DNA, Viral/genetics
  17. Identification of potential hot spots in the carboxy-terminal part of the Epstein-Barr virus (EBV) BNLF-1 gene in both malignant and benign EBV-associated diseases: high frequency of a 30-bp deletion in Malaysian and Danish peripheral T-cell lymphomas
    Sandvej K, Peh SC, Andresen BS, Pallesen G
    Blood, 1994 Dec 15;84(12):4053-60.
    PMID: 7994023
    In this study, we have sequenced the C-terminal part of the Epstein-Barr virus (EBV)-BNLF-1 gene encoding for the latent membrane protein-1 from tissues of EBV-positive Danish Hodgkin's disease (HD) and of Danish and Malaysian peripheral T-cell lymphomas (PTLs) and from tonsils of Danish infectious mononucleosis (IM). Our study showed that some of the 7 single-base mutations and the 30-bp deletion previously detected between codons of amino acid 322 and 366 in the BNLF-1 gene of the nasopharyngeal carcinoma cell line CAO were present in all Malaysian PTLs and in 60% of the Danish PTLs. In HD and the IM cases, the mutations were present in about 30%. The 30-bp deletion and the single base mutations occurred independently, and mutations were detectable in the majority of EBV type B-positive cases. These findings suggest that the 30-bp deletion and the 7 single-base mutations in the C-terminal part of the CAO-BNLF-1 gene do not characterize a new EBV type A substrain. Rather, some of the positions of single base mutations and the 30-bp deletion are hot spots that may have mutated independently through the evolution of EBV strains.
    Matched MeSH terms: DNA, Viral/genetics
  18. High-risk human papillomavirus infection in different histological subtypes of renal cell carcinoma
    Farhadi A, Behzad-Behbahani A, Geramizadeh B, Sekawi Z, Rahsaz M, Sharifzadeh S
    J Med Virol, 2014 Jul;86(7):1134-44.
    PMID: 24700118 DOI: 10.1002/jmv.23945
    Limited data exist regarding whether a high-risk human papillomavirus (HR-HPV) infection increases the risk of developing renal cell carcinoma. The aim of this study was to investigate whether HPV infection has a role in the pathogenesis or development of a certain histological subtype of renal cell carcinoma. Formalin-fixed paraffin-embedded (FFPE) specimens of 122 patients with histopathologically proven renal cell carcinoma and their respective peritumoral tissues were examined. The presence of HPV-DNA was determined by a combination of MY/GP+ consensus primers and HPV-16/18 type specific nested PCRs followed by direct sequencing. Catalyzed signal-amplified colorimetric in situ hybridization (CSAC-ISH) technique was applied to determine the physical status of viral genome. The expression of p16INK4a and HPV L1 capsid proteins was evaluated using immunohistochemistry. HPV genome was detected in 37 (30.3%) tumor specimens and their four (4.1%) corresponding peritumoral tissues. HPV-18 was the most common viral type identified followed by HPV-16 and 58. Immunoexpression of p16INK4a was detected in 24 (20.3%) cases. Data analysis showed a significant correlation between p16INK4a expression and the presence of HR-HPV DNA (P DNA. Diffuse signal pattern was identified in 15 (83.3%) samples whereas a mixed pattern of diffuse and punctate signals was only detectable in three cases. The results indicate an association of HR-HPV types with renal cell carcinoma. It is proposed that HPV infection in high-grade tumors might precede disease progression in a number of tumors, particularly of the papillary subtype.
    Matched MeSH terms: DNA, Viral/genetics
  19. Fulltext Gene expression profiles in primary duodenal chick cells following transfection with avian influenza virus H5 DNA plasmid encapsulated in silver nanoparticles
    Jazayeri SD, Ideris A, Shameli K, Moeini H, Omar AR
    Int J Nanomedicine, 2013;8:781-90.
    PMID: 23459681 DOI: 10.2147/IJN.S39074
    In order to develop a systemically administered safe and effective nonviral gene delivery system against avian influenza virus (AIV) that induced cytokine expression, the hemagglutinin (H5) gene of AIV, A/Ck/Malaysia/5858/04 (H5N1) and green fluorescent protein were cloned into a coexpression vector pIRES (pIREGFP-H5) and formulated using green synthesis of silver nanoparticles (AgNPs) with poly(ethylene glycol) and transfected into primary duodenal cells taken from 18-day-old specific-pathogen-free chick embryos. The AgNPs were prepared using moderated temperature and characterized for particle size, surface charge, ultraviolet-visible spectra, DNA loading, and stability. AgNPs and AgNP-pIREGFP-H5 were prepared in the size range of 13.9 nm and 25 nm with a positive charge of +78 ± 0.6 mV and +40 ± 6.2 mV, respectively. AgNPs with a positive surface charge could encapsulate pIREGFP-H5 efficiently. The ultraviolet-visible spectra for AgNP-pIREGFP-H5 treated with DNase I showed that the AgNPs were able to encapsulate pIREGFP-H5 efficiently. Polymerase chain reaction showed that AgNP-pIREGFP-H5 entered into primary duodenal cells rapidly, as early as one hour after transfection. Green fluorescent protein expression was observed after 36 hours, peaked at 48 hours, and remained stable for up to 60 hours. In addition, green fluorescent protein expression generally increased with increasing DNA concentration and time. Cells were transfected using Lipocurax in vitro transfection reagent as a positive control. A multiplex quantitative mRNA gene expression assay in the transfected primary duodenal cells via the transfection reagent and AgNPs with pIREGFP-H5 revealed expression of interleukin (IL)-18, IL-15, and IL-12β.
    Matched MeSH terms: DNA, Viral/genetics
  20. Diversity of hepatitis B virus infecting Malaysian candidate blood donors is driven by viral and host factors
    Meldal BH, Bon AH, Prati D, Ayob Y, Allain JP
    J Viral Hepat, 2011 Feb;18(2):91-101.
    PMID: 20196797 DOI: 10.1111/j.1365-2893.2010.01282.x
    Malaysia is a medium endemic country for hepatitis B virus (HBV) infection but little is known about HBV strains circulating in Malaysian blood donors. Viral load, HBsAg concentrations and nested PCR products from 84 HBV surface antigen (HBsAg) positive samples were analysed in detail. Median viral load was 3050 IU/mL and median HBsAg 1150 IU/mL. Fifty-six full genome, 20 pre-S/S, 1 S gene and six basic core promoter/precore-only sequences were obtained. Genotypes B and C were present at a ratio of 2:1, and two genotype D samples were obtained, both from donors of Indian background. Phylogenetically, genotype B was more diverse with subgenotypes B2-5, B7 and B8 present, while most genotype C strains were from subgenotype C1. Genotypes B and C were equally frequent in ethnic Malays, but 80% of strains from Chinese were genotype B. HBsAg concentrations were higher in genotype C than in genotype B, in Chinese than Malays and in donors under the age of 30. HBV vaccine escape substitutions (P120S/T, I126N and G145G) were present in six strains. In the large surface protein, immuno-inactive regions were more mutated than CD8 epitopes and the major hydrophilic region. Strains of genotype B or from ethnic Malays had higher genetic diversity than strains of genotype C or from Chinese donors. Hence HBV strains circulating in Malaysia are phylogenetically diverse reflecting the ethnic mix of its population. Ethnic Malays carry lower HBsAg levels and higher genetic diversity of the surface antigen, possibly resulting in more effective immune control of the infection.
    Matched MeSH terms: DNA, Viral/genetics
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