Displaying publications 281 - 300 of 332 in total

Abstract:
Sort:
  1. Production of the matrix protein of Nipah virus in Escherichia coli: virus-like particles and possible application for diagnosis
    Subramanian SK, Tey BT, Hamid M, Tan WS
    J Virol Methods, 2009 Dec;162(1-2):179-83.
    PMID: 19666056 DOI: 10.1016/j.jviromet.2009.07.034
    The broad species tropism of Nipah virus (NiV) coupled with its high pathogenicity demand a rapid search for a new biomarker candidate for diagnosis. The matrix (M) protein was expressed in Escherichia coli and purified using a Ni-NTA affinity column chromatography and sucrose density gradient centrifugation. The recombinant M protein with the molecular mass (Mr) of about 43 kDa was detected by anti-NiV serum and anti-myc antibody. About 50% of the M protein was found to be soluble and localized in cytoplasm when the cells were grown at 30 degrees C. Electron microscopic analysis showed that the purified M protein assembled into spherical particles of different sizes with diameters ranging from 20 to 50 nm. The purified M protein showed significant reactivity with the swine sera collected during the NiV outbreak, demonstrating its potential as a diagnostic reagent.
    Matched MeSH terms: Antibodies, Viral/blood
  2. The influence of antibody levels in dengue diagnosis by polymerase chain reaction
    Chan SY, Kautner IM, Lam SK
    J Virol Methods, 1994 Oct;49(3):315-22.
    PMID: 7868649
    The potential of RT-PCR to rapidly diagnose dengue infections from both acute and convalescent phase patients' sera was evaluated. The RNA extraction method involved binding of the viral RNA to silica particles in the presence of high concentration of guanidine thiocyanate. The protocol that was established was sensitive enough to detect 40 plaque forming units per 100 microliter of serum and results could be obtained within one day. Results from this study indicate that clinical samples should be collected in the early acute phase of illness when anti-dengue antibodies were undetectable or of low titres to ensure a more reliable diagnosis.
    Matched MeSH terms: Antibodies, Viral/blood*
  3. Fulltext Saffold virus infection in children, Malaysia, 2009
    Chua KB, Voon K, Yu M, Ali WN, Kasri AR, Wang LF
    Emerg Infect Dis, 2011 Aug;17(8):1562-4.
    PMID: 21801653 DOI: 10.3201/eid1708.101380
    Matched MeSH terms: Antibodies, Viral/blood*
  4. Fulltext Nipah virus among military personnel involved in pig culling during an outbreak of encephalitis in Malaysia, 1998-1999
    Ali R, Mounts AW, Parashar UD, Sahani M, Lye MS, Isa MM, et al.
    Emerg Infect Dis, 2001 Jul-Aug;7(4):759-61.
    PMID: 11592256
    Matched MeSH terms: Antibodies, Viral/blood
  5. Serological evidence of DENV, JEV, and ZIKV among the indigenous people (Orang Asli) of Peninsular Malaysia
    Khor CS, Mohd-Rahim NF, Hassan H, Tan KK, Zainal N, Teoh BT, et al.
    J Med Virol, 2020 08;92(8):956-962.
    PMID: 31814135 DOI: 10.1002/jmv.25649
    Dengue virus (DENV), Japanese encephalitis virus (JEV), and Zika virus (ZIKV) are mosquito-borne flavivirus of medical importance in tropical countries such as Malaysia. However, much remains unknown regarding their prevalence among the underserved indigenous people (Orang Asli) living in communities in the forest fringe areas of Peninsular Malaysia. Information on the prevalence of diseases is necessary to elevate the effectiveness of disease control and preventive measures. This study aimed to determine the seroprevalence of the three major flaviviruses among the Orang Asli and investigate the association between demographic factors and seropositivities. Sampling activities were conducted in the Orang Asli villages to obtain serum samples and demographic data from consenting volunteers. The presence of DENV, JEV, and ZIKV immunoglobulin G (IgG) antibodies in the sera were examined using commercial enzyme-linked immunosorbent assay kits. A focus reduction neutralization assay was performed to measure virus-specific neutralizing antibodies. A total of 872 serum samples were obtained from the Orang Asli volunteers. Serological assay results revealed that DENV IgG, JEV IgG, and ZIKV IgG seropositivities among the Orang Asli were at 4.9%, 48.4%, and 13.2%, respectively. Neutralizing antibodies (FRNT50 ≥ 1:40) against JEV and ZIKV were found in 86.7% and 100.0%, respectively, out of the samples tested. Positive serology to all three viruses corresponded significantly to the age of the volunteers with increasing seropositivity in older volunteers. Findings from the study suggest that Orang Asli are at significant risk of contracting JEV and ZIKV infections despite the lack of active transmission of the viruses in the country.
    Matched MeSH terms: Antibodies, Viral/blood*
  6. Seroprevalence of seasonal and pandemic influenza a in Kuala Lumpur, Malaysia in 2008-2010
    Sam IC, Shaw R, Chan YF, Hooi PS, Hurt AC, Barr IG
    J Med Virol, 2013 Aug;85(8):1420-5.
    PMID: 23765779 DOI: 10.1002/jmv.23622
    Relatively little is known about the burden of influenza in tropical countries. The seroprevalence of pandemic influenza A (H1N1) 2009, seasonal H1N1 and H3N2 was determined in Kuala Lumpur, Malaysia. Pre- and post-pandemic residual laboratory sera were tested by hemagglutination-inhibition. The seroprevalence of A(H1N1)pdm09 increased from 3.7% pre-pandemic to 21.9% post-pandemic, giving an overall cumulative incidence of 18.1% (95% CI, 13.8-22.5%), mainly due to increases in those <5, 5-17, and 18-29 years old. In contrast with findings from USA, Europe, and Australia, pre-existing seroprevalence to A(H1N1)pdm09 was low at 5.6% in the elderly age group of >55 years. A(H1N1)pdm09 affected almost a third of those <30 years in Kuala Lumpur. Pre-pandemic seroprevalence was 14.7% for seasonal H1N1 and 21.0% for H3N2, and these rates did not change significantly after the pandemic. Seasonal and pandemic influenza cause a considerable burden in tropical Malaysia, particularly in children and young adults.
    Matched MeSH terms: Antibodies, Viral/blood
  7. Experimental cross-infection of sheep and goats with different isolates of contagious ecthyma virus
    Zamri-Saad M, Roshidah I, al-Ajeeli K
    Aust Vet J, 1994 Jul;71(7):218-20.
    PMID: 7945102
    Matched MeSH terms: Antibodies, Viral/biosynthesis
  8. Fulltext Serological Evidence of Zika Virus Infection in Febrile Patients and Healthy Blood Donors in Sabah, Malaysian Borneo, 2017-2018
    Ngwe Tun MM, Mori D, Sabri SB, Kugan O, Shaharom SB, John J, et al.
    Am J Trop Med Hyg, 2021 Nov 22;106(2):601-606.
    PMID: 34814105 DOI: 10.4269/ajtmh.21-0802
    Several Zika virus (ZIKV) seroprevalence studies have been conducted in Africa, Asia, Oceania, the Americas, and the Caribbean. However, studies on ZIKV seroprevalence are limited in Malaysia though several studies have shown that the disease is endemic in the Malaysian state of Sabah. To evaluate the seroprevalence of ZIKV infection, 818 serum samples were collected from febrile patients and healthy blood donors from the Kudat and Kota Kinabalu districts in Sabah from 2017 to 2018. They were screened for ZIKV infection by IgM and IgG ELISA, and positive ZIKV IgM samples were subjected to a 90% neutralization test for confirmation. Twenty-four (6% [95% CI 4 to 8]) confirmed and two (0.5% [95% CI 0.13 to 1.8]) probable ZIKV infections were detected among 400 febrile illness patients. Of 418 healthy blood donor samples, six (1.4% [95% CI 0.65 to 3]) were determined as confirmed ZIKV infections and six (1.4% [95% CI 0.65 to 3]) indicated probable ZIKV infection. This is the first study on the seroprevalence of ZIKV infections among patients and healthy blood donors in Sabah. Compared with previous studies in Malaysia, this study shows that the incidence of ZIKV infection has increased. It also suggests that a sero-surveillance system is essential to determine the circulation of ZIKV in Sabah, Malaysia.
    Matched MeSH terms: Antibodies, Viral/blood*
  9. Fulltext A point-of-care test for measles diagnosis: detection of measles-specific IgM antibodies and viral nucleic acid
    Warrener L, Slibinskas R, Chua KB, Nigatu W, Brown KE, Sasnauskas K, et al.
    Bull World Health Organ, 2011 Sep 01;89(9):675-82.
    PMID: 21897488 DOI: 10.2471/BLT.11.088427
    OBJECTIVE: To evaluate the performance of a newly developed point-of-care test (POCT) for the detection of measles-specific IgM antibodies in serum and oral fluid specimens and to assess if measles virus nucleic acid could be recovered from used POCT strips.

    METHODS: The POCT was used to test 170 serum specimens collected through measles surveillance or vaccination programmes in Ethiopia, Malaysia and the Russian Federation: 69 were positive for measles immunoglobulin M (IgM) antibodies, 74 were positive for rubella IgM antibodies and 7 were positive for both. Also tested were 282 oral fluid specimens from the measles, mumps and rubella (MMR) surveillance programme of the United Kingdom of Great Britain and Northern Ireland. The Microimmune measles IgM capture enzyme immunoassay was the gold standard for comparison. A panel of 24 oral fluids was used to investigate if measles virus haemagglutinin (H) and nucleocapsid (N) genes could be amplified by polymerase chain reaction directly from used POCT strips.

    FINDINGS: With serum POCT showed a sensitivity and specificity of 90.8% (69/76) and 93.6% (88/94), respectively; with oral fluids, sensitivity and specificity were 90.0% (63/70) and 96.2% (200/208), respectively. Both H and N genes were reliably detected in POCT strips and the N genes could be sequenced for genotyping. Measles virus genes could be recovered from POCT strips after storage for 5 weeks at 20-25 °C.

    CONCLUSION: The POCT has the sensitivity and specificity required of a field-based test for measles diagnosis. However, its role in global measles control programmes requires further evaluation.

    Matched MeSH terms: Antibodies, Viral/blood*
  10. The prevalence of scrub typhus antibodies in residents of West Malaysia
    Robinson DM, Gan E, Donaldson JR
    Trop Geogr Med, 1976 Dec;28(4):303-8.
    PMID: 827831
    Based on the prevalence of antibody, an estimated 3% of the population of rural Malaysia is infected with Rickettsia tsutsugamushi each year, resulting in positive antibody rates in focal areas of 6 to 69%. Most of these infections do not appear to produce clinical scrub typhus. A wide range of seropositivity rates was found in areas otherwise resembling each other in predominant occupation, terrain, and nearby habitat. The prevalence rates however were significantly higher in people who worked in forested areas and significantly lower in people with urban occupations.
    Matched MeSH terms: Antibodies, Viral
  11. Leukosis and Marek's disease viruses of feral red jungle flow and domestic fowl in Malaya
    Weiss RA, Biggs PM
    J Natl Cancer Inst, 1972 Dec;49(6):1713-25.
    PMID: 4119166
    Matched MeSH terms: Antibodies, Viral
  12. Fulltext An association of Orf virus infection among sheep and goats with herd health programme in Terengganu state, eastern region of the peninsular Malaysia
    Bala JA, Balakrishnan KN, Abdullah AA, Adamu L, Noorzahari MSB, May LK, et al.
    BMC Vet Res, 2019 Jul 18;15(1):250.
    PMID: 31319873 DOI: 10.1186/s12917-019-1999-1
    BACKGROUND: Orf virus causes a scabby skin lesions which decreases productivity in small ruminants. The unknown status of this disease in the eastern region of Peninsular Malaysia warrants a study to determine sero-prevalence of orf with regards to farmers' compliance level towards the Herd Health Program (HHP) programme.

    RESULTS: Out of 504 animals, 115 were positive for Orf-virus antibodies. An overall prevalence rate of 22.8% indicated a high prevalence of orf disease in this region. It was observed that 25.1% (92/367) of goats were positive and 16.8% (23/137) of sheep sero-converted for Orf virus antibody. Several factors were measured for their possible association with prevalence of Orf virus infection. The prevalence was higher in LY farm, JC breed, kid and female animals, and in the presence of disease lesion. Chi-square analysis showed a significant association of three risk factors which are species, age and sex of the animals (P  0.05). Farms surveyed usually practised intensive management system, keeping animals in the shade at all time, due to limited availability of suitable land as a free-range grazing area. An interview with small holder farmers revealed a lack of awareness of the main goals of herd health programme. An overall compliance level of 42.7% was observed for all HHP parameters. Among the 14 main components of HHP modules, animal identification had recorded highest compliance level (84.62%) while milking management recorded the least compliance (- 82.69%). That explained why there was a high sporadic prevalence of Orf infection in this region.

    CONCLUSION: Good herd health supervision is a rehearsal target to prevent an outbreak and the spread of diseases thus reduces economic losses among farmers. Therefore, a good herd health programme should be in place, in order to prevent and control disease transmission as well as to improve herd immunity.

    Matched MeSH terms: Antibodies, Viral
  13. Fulltext The known unknowns of HPV natural history
    Gravitt PE
    J Clin Invest, 2011 Dec;121(12):4593-9.
    PMID: 22133884 DOI: 10.1172/JCI57149
    The discovery that certain high-risk strains of human papillomavirus (HR-HPV) cause nearly 100% of invasive cervical cancer has spurred a revolution in cervical cancer prevention by promoting the development of viral vaccines. Although the efficacy of these vaccines has already been demonstrated, a complete understanding of viral latency and natural immunity is lacking, and solving these mysteries could help guide policies of cervical cancer screening and vaccine use. Here, we examine the epidemiological and biological understanding of the natural history of HPV infection, with an eye toward using these studies to guide the implementation of cervical cancer prevention strategies.
    Matched MeSH terms: Antibodies, Viral/biosynthesis; Antibodies, Viral/blood; Antibodies, Viral/immunology
  14. Henipaviruses at the Interface Between Bats, Livestock and Human Population in Africa
    Mbu'u CM, Mbacham WF, Gontao P, Sado Kamdem SL, Nlôga AMN, Groschup MH, et al.
    Vector Borne Zoonotic Dis, 2019 07;19(7):455-465.
    PMID: 30985268 DOI: 10.1089/vbz.2018.2365
    Nipah virus (NiV) and Hendra virus (HeV) are closely related members within the genus Henipavirus, family Paramyxoviridae, for which fruit bats serve as the reservoir. The initial emergence of NiV infections in pigs and humans in Malaysia, and HeV infections in horses and humans in Australia, posed severe impacts on human and animal health, and continues threatening lives of humans and livestock within Southeast Asia and Australia. Recently, henipavirus-specific antibodies have also been detected in fruit bats in a number of sub-Saharan African countries and in Brazil, thereby considerably increasing the known geographic distribution of henipaviruses. Africa is progressively being recognized as a new high prevalence zone for henipaviruses, as deduced from serological and molecular evidence of past infections in Madagascar, Ghana, Republic of Congo, Gulf of Guinea, Zambia, Tanzania, Cameroon, and Nigeria lately. Serological data suggest henipavirus spillover from bats to livestock and human populations in Africa without reported clinical disease in any of these species. All virus isolation attempts have been abortive, highlighting the need for further investigations. The genome of the Ghanaian bat henipavirus designated Ghana virus (GhV), which was detected in a pteropid Eidolon helvum bat, is the only African henipavirus that has been completely sequenced limiting our current knowledge on the genetic diversity and pathogenesis of African henipaviruses. In this review, we summarize the available data on the circulation of henipaviruses in Africa, discuss potential sources for virus spillover, and highlight existing research gaps.
    Matched MeSH terms: Antibodies, Viral
  15. A graphene-based dengue immunosensor using plant-derived envelope glycoprotein domain III (EDIII) as the novel probe antigen
    Siew QY, Tan SH, Pang EL, Loh HS, Tan MTT
    Analyst, 2021 Mar 21;146(6):2009-2018.
    PMID: 33523052 DOI: 10.1039/d0an02219e
    The envelope glycoprotein domain III (EDIII) of dengue virus (DENV) has been recognised as the antigenic region responsible for receptor binding. In the present work, we have proposed a novel immunosensor constructed on a graphene-coated screen-printed carbon electrode (SPCE) using plant-derived EDIII as the probe antigen to target DENV IgG antibodies. The developed immunosensor demonstrated high sensitivity towards DENV IgG within a wide linear working range (125-2000 ng mL-1) under the optimised sensing conditions. The limit of detection was determined to be 22.5 ng mL-1. The immunosensor also showed high specificity towards DENV IgG, capable of differentiating DENV IgG from the antibodies of other infectious diseases including the similarly structured Zika virus (ZIKV). The ability of the immunosensor to detect dengue antibodies in serum samples was also verified by conducting tests on mouse serum samples. The proposed immunosensor was able to provide a binary (positive/negative) response towards the serum samples comparable to the conventional enzyme-linked immunosorbent assay (ELISA), indicating promising potential for realistic applications.
    Matched MeSH terms: Antibodies, Viral
  16. Effects of immunostimulators of microbial origin on T cells of pigs vaccinated with attenuated vaccine against Aujeszky's disease
    Andrišić M, Žarković I, Šandor K, Vujnović A, Perak Junaković E, Bendelja K, et al.
    Vet Immunol Immunopathol, 2022 Jan;243:110365.
    PMID: 34920287 DOI: 10.1016/j.vetimm.2021.110365
    Aujeszky's disease (AD) is a viral infectious disease caused by Suid herpesvirus 1 (SuHV-1). Vaccination and eradication of AD in domestic pigs is possible using marker vaccines with attenuated or inactivated SuHV-1, or subunit vaccines. However, vaccines with attenuated SuHV-1 have shown to be more potent in inducing strong cell-mediated immune response. The studies have shown that Parapoxvirus ovis, as well as Propionibacterium granulosum with lipopolysacharides (LPS) of Escherichia coli have pronounced immunomodulatory effects and that in combination with the vaccines can induce stronger humoral and cellular immune responses than use of vaccines alone. In our study distribution of peripheral blood T cell subpopulations was analysed after administration of vaccine alone (attenuated SuHV-1), immunostimulators (inactivated Parapoxvirus ovis or combination of an inactivated P. granulosum and detoxified LPS of E. coli) and combinations of vaccine with each immunostimulator to the 12-week old piglets. Throughout the study no significant changes were found in the proportions of γδ and most αβ T cell subpopulations analysed. However, on the seventh day of the study combination of an inactivated P. granulosum and LPS of E. coli with vaccine induced transient but significant increase of the proportions of CD4+CD8α+ and CD4-CD8α+ αβ T cells, that have been strongly associated with early protection of SuHV-1 infected pigs. Our findings indicate that combination of inactivated P. granulosum and detoxified E. coli LPS could be used for enhancement of a cellular immune response induced by vaccines against AD.
    Matched MeSH terms: Antibodies, Viral
  17. Fulltext A novel Pseudorabies virus vaccine developed using HDR-CRISPR/Cas9 induces strong humoral and cellular immune response in mice
    Luo C, Wang Q, Guo R, Zhang J, Zhang J, Zhang R, et al.
    Virus Res, 2022 Dec;322:198937.
    PMID: 36174845 DOI: 10.1016/j.virusres.2022.198937
    Outbreaks of Pseudorabies (PR) by numerous highly virulent and antigenic variant Pseudorabies virus (PRV) strains have been causing severe economic losses to the pig industry in China since 2011. However, current commercial vaccines are often unable to induce thorough protective immunity. In this study, a TK/gI/gE deleted recombinant PRV expressing GM-CSF was developed by using the HDR-CRISPR/Cas9 system. Here, a four-sgRNA along with the Cas9D10A targeting system was utilized for TK/gI/gE gene deletion and GM-CSF insertion. Our study showed that the four-sgRNA targeting system appeared to have higher knock-in efficiency for PRVs editing. The replication of the recombinant PRVs were slightly lower than that of the parental strain, but they appeared to have similar properties in terms of growth curves and plaque morphology. The mice vaccinated with the recombinant PRV expressing GM-CSF via intramuscular injection showed no obvious clinical symptoms, milder pathological lesions, and were completely protected against wild-type PRV challenge. When compared to the triple gene-deleted PRV, the gB antibodies and neutralizing antibody titers were improved and the immunized mice appeared to have lower viral load and higher mRNA levels of IL-2, IL-4, IL-6, and IFN-γ in spleens. Our study offers a novel approach for recombinant PRV construction, and the triple gene-deleted PRV expressing GM-CSF could serve as a promising vaccine candidate for PR control.
    Matched MeSH terms: Antibodies, Viral
  18. Structurally conserved binding sites of hemagglutinin as targets for influenza drug and vaccine development
    Yusuf M, Konc J, Sy Bing C, Trykowska Konc J, Ahmad Khairudin NB, Janezic D, et al.
    J Chem Inf Model, 2013 Sep 23;53(9):2423-36.
    PMID: 23980878 DOI: 10.1021/ci400421e
    ProBiS is a new method to identify the binding site of protein through local structural alignment against the nonredundant Protein Data Bank (PDB), which may result in unique findings compared to the energy-based, geometry-based, and sequence-based predictors. In this work, binding sites of Hemagglutinin (HA), which is an important target for drugs and vaccines in influenza treatment, have been revisited by ProBiS. For the first time, the identification of conserved binding sites by local structural alignment across all subtypes and strains of HA available in PDB is presented. ProBiS finds three distinctive conserved sites on HA's structure (named Site 1, Site 2, and Site 3). Compared to other predictors, ProBiS is the only one that accurately defines the receptor binding site (Site 1). Apart from that, Site 2, which is located slightly above the TBHQ binding site, is proposed as a potential novel conserved target for membrane fusion inhibitor. Lastly, Site 3, located around Helix A at the stem domain and recently targeted by cross-reactive antibodies, is predicted to be conserved in the latest H7N9 China 2013 strain as well. The further exploration of these three sites provides valuable insight in optimizing the influenza drug and vaccine development.
    Matched MeSH terms: Antibodies, Viral/immunology
  19. Evaluation of the safety, reactogenicity and immunogenicity of FluBlok® trivalent recombinant baculovirus-expressed hemagglutinin influenza vaccine administered intramuscularly to healthy adults 50-64 years of age
    Baxter R, Patriarca PA, Ensor K, Izikson R, Goldenthal KL, Cox MM
    Vaccine, 2011 Mar 9;29(12):2272-8.
    PMID: 21277410 DOI: 10.1016/j.vaccine.2011.01.039
    Alternative methods for influenza vaccine production are needed to ensure adequate supplies.
    Matched MeSH terms: Antibodies, Viral/blood
  20. Fulltext Improving the potency of DNA vaccine against chicken anemia virus (CAV) by fusing VP1 protein of CAV to Marek's Disease Virus (MDV) type-1 VP22 protein
    Moeini H, Omar AR, Rahim RA, Yusoff K
    Virol J, 2011;8:119.
    PMID: 21401953 DOI: 10.1186/1743-422X-8-119
    Studies have shown that the VP22 gene of Marek's Disease Virus type-1 (MDV-1) has the property of movement between cells from the original cell of expression into the neighboring cells. The ability to facilitate the spreading of the linked proteins was used to improve the potency of the constructed DNA vaccines against chicken anemia virus (CAV).
    Matched MeSH terms: Antibodies, Viral/immunology
Related Terms
Filters
Contact Us

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

External Links