Displaying publications 61 - 80 of 175 in total

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  1. Fulltext Molecular detection and characterisation of Domestic Cat Hepadnavirus (DCH) from blood and liver tissues of cats in Malaysia
    Anpuanandam K, Selvarajah GT, Choy MMK, Ng SW, Kumar K, Ali RM, et al.
    BMC Vet Res, 2021 Jan 06;17(1):9.
    PMID: 33407487 DOI: 10.1186/s12917-020-02700-0
    BACKGROUND: A new domestic cat hepadnavirus (DCH, family Hepadnaviridae) was first reported from whole blood samples of domestic cats in Australia in 2018, and from cat serum samples in Italy in 2019. The pathogenesis of DCH is unknown, but it was reported in cats with viraemia (6.5-10.8%), chronic hepatitis (43%) and hepatocellular carcinoma (28%). Recent reports suggest that DCH resembles the human hepatitis B virus (HBV) and its related hepatopathies. This study aims to detect and characterize DCH among domestic cats in Malaysia. A cross-sectional study was performed on 253 cats, of which 87 had paired blood and liver samples, entailing whole-genome sequencing and phylogenetic analysis of DCH from a liver tissue sample.

    RESULTS: Among the 253 cats included in this study, 12.3% of the whole blood samples tested positive for DCH. The detection rate was significantly higher in pet cats (16.6%, n = 24/145) compared to shelter cats (6.5%, n = 7/108). Liver tissues showed higher a DCH detection rate (14.9%, n = 13/87) compared to blood; 5 out of these 13 cats tested positive for DCH in their paired liver and blood samples. Serum alanine transaminase (ALT) was elevated (> 95 units/L) in 12 out of the 23 DCH-positive cats (52.2%, p = 0.012). Whole-genome sequence analysis revealed that the Malaysian DCH strain, with a genome size of 3184 bp, had 98.3% and 97.5% nucleotide identities to the Australian and Italian strains, respectively. The phylogenetic analysis demonstrated that the Malaysian DCH genome was clustered closely to the Australian strain, suggesting that they belong to the same geographically-determined genetic pool (Australasia).

    CONCLUSIONS: This study provided insights into a Malaysian DCH strain that was detected from a liver tissue. Interestingly, pet cats or cats with elevated ALT were significantly more likely to be DCH positive. Cats with positive DCH detection from liver tissues may not necessarily have viraemia. The impact of this virus on inducing liver diseases in felines warrants further investigation.

    Matched MeSH terms: DNA, Viral/analysis
  2. Detection of HHV-6 genotypes by in situ hybridization with variant-specific oligonucleotide probes
    Arivananthan M, Yadav M, Kumar S
    J Virol Methods, 1997 Jun;66(1):5-14.
    PMID: 9220385
    Human herpesvirus-6 exists in two forms, HHV-6A which has not been clearly associated with any disease, and HHV-6B, the causative agent of exanthem subitum. The two variants have been distinguished by techniques such as dot blotting and restriction fragment length polymorphism of PCR products. This study aims to establish the prevalence of HHV-6A and HHV-6B in carcinoma tissues using variant-specific oligonucleotide probes. A total of 73 archived carcinoma biopsies from the oral, salivary gland, larynx, breast and cervix were obtained with seven histologically normal controls. In situ hybridization was carried out with nonradioactively labelled variant-specific probes. Samples that hybridized with both variant A and B probes were subjected further to nested PCR and digested with HindIII to distinguish the variants. A hybridization signal was observed in 76.2% of oral carcinoma tissue and 75.0% of salivary gland carcinoma tissue. In contrast, only 33.3% of cervical carcinoma tissue were positive for HHV-6 DNA. A hybridization signal was noted in all 4 laryngeal carcinoma tissues studied. However, the 10 breast carcinoma tissues studied were negative, as was the histologically normal tissue. The virus possesses tumourigenic potential and demonstrates virus transactivating properties. The frequency of HHV-6 variants in certain tumours suggest a cofactorial role in multistep carcinogenesis. While PCR amplifies selectively the predominant variant in a sample, this was not seen by in situ hybridization. The in situ hybridization technique allowed the localization of both HHV-6A and HHV-6B in the nuclei of transformed regions.
    Matched MeSH terms: DNA, Viral/analysis
  3. Genotypes of Japanese encephalitis virus isolated in three states in Malaysia
    Tsuchie H, Oda K, Vythilingam I, Thayan R, Vijayamalar B, Sinniah M, et al.
    Am J Trop Med Hyg, 1997 Feb;56(2):153-8.
    PMID: 9080873
    Two hundred forty nucleotides from the pre-membrane gene region of 12 Japanese encephalitis virus (JEV) strains isolated from three different regions of Malaysia from 1993 to 1994 were sequenced and compared with each other and with the JEV strains from different geographic areas in Asia. These 12 Malaysian isolates were classified into two genotypes. The four JEV strains isolated from Sarawak in 1994 and the four JEV strains isolated from Sepang, Selangor in 1993 were classified into one genotype that included earlier isolated strains from Malaysia (JE-827 from Sarawak in 1968 and WTP/70/22 from Kuala Lumpur in 1970). The four JEV strains from Ipoh, Perak in 1994 were classified into another genotype that included JEV strains isolated from northern Thailand and Cambodia. In an earlier report, 10 JEV strains from Sabak Bernam, Selangor in 1992 were classified into the largest genotype that included strains isolated in temperate regions such as Japan, China, and Taiwan. The data indicate that at least three genotypes of JEV have been circulating in Malaysia.
    Matched MeSH terms: DNA, Viral/chemistry*
  4. Chronic hepatitis B virus infection in Asian countries
    Merican I, Guan R, Amarapuka D, Alexander MJ, Chutaputti A, Chien RN, et al.
    J Gastroenterol Hepatol, 2000 Dec;15(12):1356-61.
    PMID: 11197043
    Of the estimated 50 million new cases of hepatitis B virus (HBV) infection diagnosed annually, 5-10% of adults and up to 90% of infants will become chronically infected, 75% of these in Asia where hepatitis B is the leading cause of chronic hepatitis, cirrhosis and hepatocellular carcinoma (HCC). In Indonesia, 4.6% of the population was positive for HBsAg in 1994 and of these, 21% were positive for HBeAg and 73% for anti-HBe; 44% and 45% of Indonesian patients with cirrhosis and HCC, respectively, were HBsAg positive. In the Philippines, there appear to be two types of age-specific HBsAg prevalence, suggesting different modes of transmission. In Thailand, 8-10% of males and 6-8% of females are HBsAg positive, with HBsAg also found in 30% of patients with cirrhosis and 50-75% of those with HCC. In Taiwan, 75-80% of patients with chronic liver disease are HBsAg positive, and HBsAg is found in 34% and 72% of patients with cirrhosis and HCC, respectively. In China, 73% of patients with chronic hepatitis and 78% and 71% of those with cirrhosis and HCC, respectively, are HBsAg positive. In Singapore, the prevalence of HBsAg has dropped since the introduction of HBV vaccination and the HBsAg seroprevalence of unvaccinated individuals over 5 years of age is 4.5%. In Malaysia, 5.24% of healthy volunteers, with a mean age of 34 years, were positive for HBsAg in 1997. In the highly endemic countries in Asia, the majority of infections are contracted postnatally or perinatally. Three phases of chronic HBV infection are recognized: phase 1 patients are HBeAg positive with high levels of virus in the serum and minimal hepatic inflammation; phase 2 patients have intermittent or continuous hepatitis of varying degrees of severity; phase 3 is the inactive phase during which viral concentrations are low and there is minimal inflammatory activity in the liver. In general, patients who clear HBeAg have a better prognosis than patients who remain HBeAg-positive for prolonged periods of time. The outcome after anti-HBe seroconversion depends on the degree of pre-existing liver damage and any subsequent HBV reactivation. Without pre-existing cirrhosis, there may be only slight fibrosis or mild chronic hepatitis, but with pre-existing cirrhosis, further complications may ensue. HBsAg-negative chronic hepatitis B is a phase of chronic HBV infection during which a mutation arises resulting in the inability of the virus to produce HBeAg. Such patients tend to have more severe liver disease and run a more rapidly progressive course. The annual probability of developing cirrhosis varies from 0.1 to 1.0% depending on the duration of HBV replication, the severity of disease and the presence of concomitant infections or drugs. The annual incidence of hepatic decompensation in HBV-related cirrhosis varies from 2 to 10% and in these patients the 5-year survival rate drops dramatically to 14-35%. The annual risk of developing HCC in patients with cirrhosis varies between 1 and 6%; the overall reported annual detection rate of HCC in surveillance studies, which included individuals with chronic hepatitis B and cirrhosis, is 0.8-4.1%. Chronic hepatitis B is not a static disease and the natural history of the disease is affected by both viral and host factors. The prognosis is poor with decompensated cirrhosis and effective treatment options are limited. Prevention of HBV infection thorough vaccination is still, therefore, the best strategy for decreasing the incidence of hepatitis B-associated cirrhosis and HCC.
    Matched MeSH terms: DNA, Viral/physiology
  5. HHV-6 antigen and viral DNA detected in cervical cells from archived tissue using histochemical staining and hybridization
    Yadav M, Arivananthan M, Kumar S
    Clin Diagn Virol, 1996 Oct;7(1):23-33.
    PMID: 9077427
    BACKGROUND: Human herpesvirus type 6 (HHV-6), an ubiquitous virus, is the causative agent for exanthem subitum. The virus is frequently associated with lymphoproliferative disorders and other diseases. Recently, we have reported the frequent presence of HHV-6 in oral carcinoma and the present study extends the observation to cervical carcinoma.

    OBJECTIVE: To examine the presence of HHV-6 in cervical carcinoma.

    STUDY DESIGN: Formalin-fixed, paraffin-embedded cervical carcinoma tissues were examined for the presence of HHV-6 by immunohistochemistry using two monoclonal antibodies that react to HHV-6-encoded p41/38 and gp116/64/54. In situ hybridization with variant-specific probes were used to type the HHV-6 DNA sequences present.

    RESULTS: A total of 14/26 (53.9%) carcinoma tissue specimens and 5/8 (62.5%) normal tissue specimens were positive for viral antigens. In situ hybridization studies revealed the presence of HHV-6 DNA sequences in 10/26 (38.5%) carcinoma tissue specimens and 1/8 (12.5%) normal tissue specimens. In the normal tissue, the HHV-6 was present in the endocervical ciliated columnar-epithelial cells and some cells in the subepithelial mucosa but in the carcinoma, the transformed cells were positive for the virus.

    CONCLUSIONS: HHV-6 viral proteins and DNA were found in more than one third of the cervical tissue examined suggesting possible viral expression in these tumours. The significance of the distribution and role of the HHV-6 in cervical tissue remains unclear. Since HHV-6 has an oncogenic potential, the virus may cooperate with other transforming agents for the progression of the disease.

    Matched MeSH terms: DNA, Viral/analysis*
  6. HIV type 1 subtypes in Malaysia include B, C, and E
    Brown TM, Robbins KE, Sinniah M, Saraswathy TS, Lee V, Hooi LS, et al.
    AIDS Res Hum Retroviruses, 1996 Nov 20;12(17):1655-7.
    PMID: 8947304
    Matched MeSH terms: DNA, Viral/analysis
  7. Survey of type 6 group variants of hepatitis C virus in Southeast Asia by using a core-based genotyping assay
    Mellor J, Walsh EA, Prescott LE, Jarvis LM, Davidson F, Yap PL, et al.
    J Clin Microbiol, 1996 Feb;34(2):417-23.
    PMID: 8789027
    Previous surveys of the prevalences of genotypes of hepatitis C virus (HCV) in different populations have often used genotyping assays based upon analysis of amplified sequences from the 5' noncoding region (5'NCR), such as restriction fragment length polymorphism (RFLP) or hybridization with type-specific probes (e.g., InnoLipa). Although highly conserved, this region contains several type-specific nucleotide polymorphisms that allow major genotypes 1 to 6 to be reliably identified. Recently, however, novel HCV variants found in Vietnam and Thailand that are distantly related to the type 6a genotype (type 6 group) by phylogenetic analysis of coding regions of the genome often have sequences in the 5'NCR that are similar or identical to those of type 1 and could therefore not be identified by an assay of sequences in this region. We developed a new genotyping assay based upon RFLP of sequences amplified from the more variable core region to investigate their distribution elsewhere in southeast (SE) Asia. Among 108 samples from blood donors in seven areas that were identified as type 1 by RFLP in the 5'NCR, type 6 group variants were found in Thailand (7 from 28 samples originally identified as type 1) and Burma (Myanmar) (1 of 3) but were not found in Hong Kong (n = 43), Macau (n = 8), Taiwan (n = 6), Singapore (n = 2), or Malaysia (n = 18). Although this small survey suggests a relatively limited distribution for type 6 group variants in SE Asia, larger studies will be required to explore their distribution in other geographical regions and the extent to which their presence would limit the practical usefulness of 5'NCR-based genotyping assays for clinical or epidemiological purposes.
    Matched MeSH terms: DNA, Viral/genetics
  8. Genetic study of Japanese encephalitis viruses isolated in Malaysia
    Tsuchie H, Oda K, Vythilingam I, Thayan R, Vijayamalar B, Sinniah M, et al.
    Jpn. J. Med. Sci. Biol., 1994 Apr;47(2):101-7.
    PMID: 7853748
    Two hundred and forty nucleotides from the pre-M gene region of 10 Japanese encephalitis (JE) virus strains isolated in Malaysia in 1992 were sequenced and compared with the other JE virus strains from different geographic areas in Asia. Our JE virus strains belong to the largest genotypic group that includes strains isolated in temperate regions such as Japan, China, and Taiwan. Our Malaysian JE virus strains differed in 32 nucleotides (13.3%) from WTP/70/22 strain isolated from Malaysia in 1970, which belonged to another distinct genotypic group.
    Matched MeSH terms: DNA, Viral/genetics
  9. Fulltext Detection of apoptotic cells in Vero cell cultures inoculated with samples derived from fatal cases of Sarawak acute childhood viral infection
    AbuBakar S, Shafee N, Chee HY
    Med J Malaysia, 1998 Sep;53(3):293-5.
    PMID: 10968171
    Infectious agent(s) causing the fatal Sarawak acute childhood viral infection (SACVI) has not been identified. In the present study, results indicating that inocula prepared from the fatal cases of SACVI induced apoptosis in Vero cell cultures are presented. These findings suggest the possible involvement of apoptotic cellular responses in SACVI.
    Matched MeSH terms: DNA, Viral/genetics
  10. Serum hepatitis B virus DNA: relationship with the e-antigen and anti-e status in chronic carriers
    Yap SF, Wong NW, Goh KL
    Malays J Pathol, 1994 Jun;16(1):57-62.
    PMID: 16329577
    The relationship between serum Hepatitis B virus DNA (HBV-DNA) and the Hepatitis B e-antigen/ anti-Hepatitis Be (HBeAg/anti-HBe) serological status in Malaysians was studied. 212 cases of asymptomatic HBV carriers were recruited for this study. 92 cases were positive for the HBeAg at the point of recruitment. 85 (92.4%) of these patients tested positive for HBV-DNA, of whom 55 (64.7%) had levels over 100pg/ml of serum. Three of the remaining 7 HBeAg positive cases who were negative for HBV-DNA subsequently seroconverted. The other 4 cases remained negative for HBV-DNA for periods of 6-12 months. Out of 113 cases who were anti-HBe positive, 12 (10.6%) gave a positive HBV-DNA result. 2 of these 12 patients were recent seroconverters; the remaining cases had transiently increased viral replicative activity which later subsided. 7 out of the 212 carriers were in the e-window period; all 7 tested negative for HBV-DNA. Our data confirm a high frequency of HBV-DNA in HBeAg positive carriers and a negative correlation between HBV-DNA and anti-HBe. An atypical profile of anti-HBe associated with HBV-DNA was observed in 10.6% of the carriers. An inverse relationship between serum HBV-DNA levels and age was also observed.
    Matched MeSH terms: DNA, Viral/blood*
  11. Viral DNA sequences of genes encoding the ATPase and the major capsid protein of tropical iridovirus isolates which are pathogenic to fishes in Japan, South China Sea and Southeast Asian countries
    Sudthongkong C, Miyata M, Miyazaki T
    Arch Virol, 2002 Nov;147(11):2089-109.
    PMID: 12417946
    Tropical iridovirus infection causes severe epizootic resulting in mass mortalities and large economic losses in freshwater ornamental fishes cultured in Southeast Asian countries, in wild fish seedlings captured in South China Sea, and in marine fishes farmed in Japan, Singapore, and Thailand. All of tropical iridovirus-infected fishes histopathologically showed the systemic formation of inclusion body-bearing cells and necrosis of virus-infected splenocytes and hematopoietic cells. We designed primer sets for the ATPase gene and the major capsid protein (MCP) gene and sequenced the PCR products derived from 5 iridovirus isolates from sea bass in South China Sea, red sea bream in Japan, brown-spotted grouper with a grouper sleepy disease in Thailand, dwarf gourami from Malaysia and African lampeye from Sumatra Island, Indonesia. The ATPase gene and the MCP gene of these 5 viral isolates were highly homologous (> 95.8%, > 94.9% identity, respectively) and the deduced amino acid sequences of the ATPase and the MCP were also highly identical (> 98.1%, > 97.2% identity, respectively). Based on the high homology, these 5 isolates of tropical iridovirus from various fishes in geographically different regions were determined to have a single origin and to be native to Southeast Asian regions. However, these sequences were far different from those of members of the genera Ranavirus, Lymphocystivirus and Iridovirus in the Family Iridoviridae. We propose a new genus "Tropivirus" for tropical iridovirus in the Family Iridoviridae.
    Matched MeSH terms: DNA, Viral/chemistry*
  12. Comparison of herpesvirus isolates from falcons, pigeons and psittacines by restriction endonuclease analysis
    Aini I, Shih LM, Castro AE, Zee YC
    J. Wildl. Dis., 1993 Apr;29(2):196-202.
    PMID: 8387609
    Field isolates of herpesviruses recovered from falcon, pigeon, and psittacine birds were compared by restriction endonuclease (RE) analysis using four separate enzymes. Pigeon and falcon herpesviruses had strikingly similar DNA cleavage patterns, while DNA cleavage pattern of virus isolates from a double-yellow headed Amazon and an African grey parrot had different genomic patterns to both the pigeon and falcon herpesviruses. These findings support the field observations that pigeon herpesvirus causes a fatal herpesviral infection in the livers of pigeon-eating falcons.
    Matched MeSH terms: DNA, Viral/analysis
  13. Expression of Epstein-Barr virus-encoded proteins in nasopharyngeal carcinoma
    Fåhraeus R, Fu HL, Ernberg I, Finke J, Rowe M, Klein G, et al.
    Int J Cancer, 1988 Sep 15;42(3):329-38.
    PMID: 2843473
    Expression of the Epstein-Barr virus (EBV) encoded nuclear antigens (EBNA 1 to 6) and membrane-associated protein (LMP) was investigated by immunoblotting in 83 nasopharyngeal carcinoma (NPC) biopsies and 25 other tumor and normal tissue specimens from the head and neck region. Fifty-eight of the 83 NPC biopsies were large enough to yield parallel data on virus DNA and viral expression. All 16 cases of clinically diagnosed and histologically confirmed NPCs from North Africa contained EBV DNA and expressed EBNA-1. Of 31 clinically diagnosed NPCs from China, 29 contained EBV DNA and 25 of these expressed EBNA-1. One control tissue biopsy from the oropharynx of NPC patients contained EBV DNA, but none expressed EBNA-1. The latent membrane protein (LMP) was detected in 22/31 of the Chinese and in 10/16 of the North African NPC biopsies. None of the NPC biopsies or control tissues expressed detectable amounts of EBNA 2 or any of the other 4 nuclear antigens which are invariably expressed in EBV-transformed B cells. A smaller number of tumors from Malaysia and East Africa exhibited a similar pattern of expression. EBV was rescued from a nude-mouse-passaged North African NPC tumor by co-cultivation of the tumor cells with umbilical cord blood lymphocytes. The tumor expressed EBNA 1 and LMP, but not EBNA 2 or the other 4 EBNAs. The resulting LCLs expressed all 6 nuclear antigens, EBNA 1 to 6 and LMP. Our data suggest that expression of the EBV genome is regulated in a tissue-specific fashion.
    Matched MeSH terms: DNA, Viral/analysis
  14. A defect in DNA topoisomerase II activity in ataxia-telangiectasia cells
    Mohamed R, Pal Singh S, Kumar S, Lavin MF
    Biochem Biophys Res Commun, 1987 Nov 30;149(1):233-8.
    PMID: 2825700
    DNA topoisomerase type I and II activities were determined by serial dilution in nuclear extracts from control and ataxia-telangiectasia lymphoblastoid cells. Topoisomerase I activity, assayed by relaxation of supercoiled plasmid DNA, was found to be approximately the same in both cell types. In order to remove interference from topoisomerase I, the activity of topoisomerase II was measured by the unknotting of knotted P4 phage DNA in the presence of ATP. The activity of topoisomerase II was markedly reduced in two ataxia-telangiectasia cell lines, AT2ABR and AT8ABR, compared to controls. This reduction in activity was detected with increasing concentration of protein and in time course experiments at a single protein concentration. A third cell line, AT3ABR, did not have a detectably lower activity of topoisomerase II when assayed under these conditions. The difference in topoisomerase II activity in the ataxia-telangiectasia cell lines examined may reflect to some extent the heterogeneity observed in this syndrome.
    Matched MeSH terms: DNA, Viral/metabolism
  15. A direct detection of human papillomavirus 16 genomic DNA using gold nanoprobes
    Azizah N, Hashim U, Gopinath SCB, Nadzirah S
    Int J Biol Macromol, 2017 Jan;94(Pt A):571-575.
    PMID: 27771413 DOI: 10.1016/j.ijbiomac.2016.10.060
    Nanoparticles have been investigated as flagging tests for the sensitive DNA recognition that can be utilized as a part of field applications to defeat restrictions. Gold nanoparticles (AuNPs) have been widely utilized due to its optical property and capacity to get functionalized with a mixed bag of biomolecules. This study exhibits the utilization of AuNPs functionalized with single-stranded oligonucleotide (AuNP-oligo test) for fast the identification of Human Papillomavirus (HPV). This test is displayed on interdigitated electrode sensor and supported by colorimetric assay. DNA conjugated AuNP has optical property that can be controlled for the applications in diagnostics. With its identification abilities, this methodology incorporates minimal effort, strong reagents and basic identification of HPV.
    Matched MeSH terms: DNA, Viral/blood*
  16. A human adenovirus species B subtype 21a associated with severe pneumonia
    Hage E, Huzly D, Ganzenmueller T, Beck R, Schulz TF, Heim A
    J Infect, 2014 Nov;69(5):490-9.
    PMID: 24975176 DOI: 10.1016/j.jinf.2014.06.015
    Between 2005 and 2013 six severe pneumonia cases (all requiring mechanical ventilation, two fatal outcomes) caused by human adenovirus type 21 (HAdV-B21) were observed in Germany. So far, HAdV-B21 was mainly associated with non-severe upper and lower respiratory tract infections. However, a few highly virulent HAdV types, e.g. HAdV-B14p1, were previously associated with severe, fatal pneumonia. Complete genomic sequences of the German HAdV-B21 pneumonia isolates formed a single phylogenetic cluster with very high sequence identity (≥ 99.897%). Compared to the HAdV-B21 prototype (only 99.319% identity), all isolates had a unique 15 amino acid deletion and a 2 amino acid insertion in the RGD loop of the penton base which may affect binding to the secondary receptor on the host cells. Moreover, a recombinant E4 gene region derived of HAdV-B3 was identified by bootscan analysis. Thus, the highly virulent, pneumotropic HAdV-B21 was denominated as subtype 21a. Surprisingly, there was 99.963% identity with agent Y/SIBU97 (only 13.4 kb available in GenBank of the 35.4 kb genome) which was associated with 10 fatalities due to cardiopulmonary failure in Sarawak, Malaysia, in 1997. In conclusion, a HAdV-B21 subtype (21a) associated with severe pneumonia in Germany was phylogenetically linked to an adenovirus isolated in Malaysia.
    Matched MeSH terms: DNA, Viral/genetics
  17. Display of hepatitis B virus PreS1 peptide on bacteriophage T7 and its potential in gene delivery into HepG2 cells
    Tang KH, Yusoff K, Tan WS
    J Virol Methods, 2009 Aug;159(2):194-9.
    PMID: 19490973 DOI: 10.1016/j.jviromet.2009.03.015
    Hepatitis B is a major public health problem worldwide which may lead to chronic liver diseases, cirrhosis and hepatocellular carcinoma. An interaction between hepatitis B virus (HBV) envelope protein, particularly the PreS1 region, and a specific cell surface receptor is believed to be the initial step of HBV infection through attachment to hepatocytes. In order to develop a gene delivery system, bacteriophage T7 was modified genetically to display polypeptides of the PreS1 region. A recombinant T7 phage displaying amino acids 60-108 of the PreS1 region (PreS1(60-108)) was demonstrated to be most effective in transfecting HepG2 cells in a dose- and time-dependant manner. The phage genome was recovered from the cell lysate and confirmed by PCR whereas the infectious form of the internalized phage was measured by a plaque-forming assay. The internalized phage exhibited the appearance of green fluorescent dots when examined by immunofluorescence microscopy. Surface modification, particularly by displaying the PreS1(60-108) enhanced phage uptake, resulting in more efficient in vitro gene transfer. The ability of the recombinant phage to transfect HepG2 cells demonstrates the potential of the phage display system as a gene therapy for liver cancer.
    Matched MeSH terms: DNA, Viral/genetics
  18. Current HIV type 1 molecular epidemiology profile and identification of unique recombinant forms in Jakarta, Indonesia
    Sahbandar IN, Takahashi K, Djoerban Z, Firmansyah I, Naganawa S, Motomura K, et al.
    AIDS Res Hum Retroviruses, 2009 Jul;25(7):637-46.
    PMID: 19621986 DOI: 10.1089/aid.2008.0266
    HIV infection is a major problem in Indonesia. The number of people living with HIV has been increasing from year to year, especially among injecting drug users (IDUs). Since there were only limited data about molecular epidemiology profiles of HIV/AIDS in Indonesia, a cross-sectional study involving 208 HIV-1-seropositive individuals was conducted in 2007 in Jakarta. The majority of participants were 16-30 years of age (64.9%) and 74.5% were male. The most frequent risk factor was injecting drug use (IDU) (45.7%) followed by heterosexual transmission (34.1%). Phylogenetic analysis of gag (p17 and p6) and env C2V3 regions showed 200 (96.2%) of 208 DNA samples were CRF01_AE and only 3 (1.4%) were subtype B. Five samples (2.4%) indicated discordant subtypes between the three aforementioned regions: three of them showed unique CRF01_AE/B recombination patterns in 2.3-kbp nucleotide sequences (from p17 to part of RT), including one sample showing similarity to CRF33_01B, reported previously in Malaysia. This study shows the current predominant subtype is CRF01_AE in every risk group, with a decreasing number of pure subtype B, and the first identification of CRF01_AE/B recombinant forms among HIV-1-seropositive Indonesians.
    Matched MeSH terms: DNA, Viral/genetics
  19. Genetic variability of genome segments 3 and 9 of Fiji disease virus field isolates
    Jiang J, Ridley AW, Tang H, Croft BJ, Johnson KN
    Arch Virol, 2008;153(5):839-48.
    PMID: 18299794 DOI: 10.1007/s00705-008-0058-1
    Fiji leaf gall is an important disease of sugarcane in Australia and other Asia-Pacific countries. The causative agent is the reovirus Fiji disease virus (FDV). Previous reports indicate that there is variation in pathology between virus isolates. To investigate the amount of genetic variation found in FDV, 25 field isolates from Australia, Papua New Guinea and Malaysia were analysed by partial sequencing of genome segments S3 and S9. There was up to 15% divergence in the nucleotide sequence among the 25 isolates. A similar amount of divergence and pattern of relationships was found for each of the two genomic segments for most of the field isolates, although reassortment of genome segments seems likely for at least one of the Papua New Guinean isolates. The finding of a high level of variation in FDV isolated in different regions has implications for quarantine and disease management.
    Matched MeSH terms: DNA, Viral/genetics
  20. Fulltext Comparison of DR. HPV Chip Kit with hybrid capture II assay for the detection of human papillomavirus in clinical samples: a preliminary study
    Rajan S, Shen TH, Santhanam J, Othman NH, Othman N, Hock TT
    Trop Biomed, 2007 Jun;24(1):17-22.
    PMID: 17568373
    Human papillomavirus (HPV) is well known as an etiological factor for the development of anogenital carcinomas. The aim of our study was to compare the performance of USFDA approved Hybrid II (HCII) Assay and recently introduced DR. HPV Chip Kit for the detection of HPV DNA in clinical cervical scrapings from 40 patients. HPV DNA testing was performed using the automated HCII Assay system and DR. HPV Chip Kit. Taking cytological results as gold standard, it was found that HCII was more sensitive (36.4%) than DR. HPV Chip Kit (18.2%) although specificity was 100% with the latter method. In addition, both these molecular methods had comparable negative and positive predictive values. It was concluded that both HCII and DR. HPV Chip Kit have comparable specificity. However, sensitivity for detection of HPV in clinical samples with HCII is almost double as compared to DR. HPV Chip Kit.
    Matched MeSH terms: DNA, Viral*
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