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Fulltext Detection of Langat virus by TaqMan real-time one-step qRT-PCR method

Muhd Radzi SF, Rückert C, Sam SS, Teoh BT, Jee PF, Phoon WH, et al.

Sci Rep, 2015;5:14007.
PMID: 26360297 DOI: 10.1038/srep14007

Langat virus (LGTV), one of the members of the tick-borne encephalitis virus (TBEV) complex, was firstly isolated from Ixodes granulatus ticks in Malaysia. However, the prevalence of LGTV in ticks in the region remains unknown. Surveillance for LGTV is therefore important and thus a tool for specific detection of LGTV is needed. In the present study, we developed a real-time quantitative reverse-transcription-polymerase chain reaction (qRT-PCR) for rapid detection of LGTV. Our findings showed that the developed qRT-PCR could detect LGTV at a titre as low as 0.1 FFU/ml. The detection limit of the qRT-PCR assay at 95% probability was 0.28 FFU/ml as determined by probit analysis (p ≤ 0.05). Besides, the designed primers and probe did not amplify ORF of the E genes for some closely related and more pathogenic viruses including TBEV, Louping ill virus, Omsk hemorrhagic fever virus (OHFV), Alkhurma virus (ALKV), Kyasanur Forest Disease virus (KFDV) and Powassan virus (POWV) which showed the acceptable specificity of the developed assay. The sensitivity of the developed method also has been confirmed by determining the LGTV in infected tick cell line as well as LGTV- spiked tick tissues.

Matched MeSH terms: Reverse Transcriptase Polymerase Chain Reaction
Measles surveillance in Taiwan, 2012-2014: Changing epidemiology, immune response, and circulating genotypes

Cheng WY, Wang HC, Wu HS, Liu MT

J Med Virol, 2016 May;88(5):746-53.
PMID: 26400063 DOI: 10.1002/jmv.24392

In Taiwan, although the coverage rate of two doses of measles-containing vaccine has been maintained at over 95% since 2001, measles outbreaks occurred in 2002, 2009, and 2011. The present study reports that 43 cases were confirmed by laboratory testing in Taiwan in 2012-2014 and that adults have emerged as one of groups susceptible to measles virus (MV) infection, who may have discrepant humoral immune reactions-indicated by the level of IgM and IgG antibodies compared to a naïve, susceptible measles case. Thirty-seven of 43 cases confirmed by RT-PCR were further characterized by genotyping. In Taiwan, genotype H1 was the major strain in circulation prior to 2010, while D9 was the most frequently detected MV genotype between 2010 and 2011. The genotyping data collected between 2012 and 2014 revealed that H1 rebounded in 2012 after an absence in 2011 and was imported from China and Vietnam. In 2014, genotype B3 first appeared in Taiwan following import from the Philippines and became the most frequently detected strain. Genotype D8, linked to importation from various countries, including India, Indonesia, Thailand, and Vietnam, showed sequence divergence. D9 was imported from Malaysia in 2014. The MV genotypes detected in Taiwan reflected the genotypes of circulating endemic measles strains in neighboring countries. A significant rise in the number of measles cases and in measles with genotypes imported from surrounding countries indicated that measles resurged in Asia in 2014. J. Med. Virol. 88:746-753, 2016. © 2015 Wiley Periodicals, Inc.

Matched MeSH terms: Reverse Transcriptase Polymerase Chain Reaction
Silencing of myeloid cell leukemia-1 by small interfering RNA improves chemosensitivity to etoposide in u-937 leukemic cells

Jafarlou M, Baradaran B, Shanehbandi D, Saedi TA, Jafarlou V, Karimi P, et al.

J Biol Regul Homeost Agents, 2016 Jan-Mar;30(1):55-65.
PMID: 27049076

A key issue in the treatment of acute myeloid leukemia (AML) is the development of drug resistance to chemotherapeutic agents. Overexpression of myeloid cell leukemia-1 (Mcl-1), an anti-apoptotic protein, is associated with tumor progression and drug resistance in leukemia and several cancers. The purpose of this study was to investigate the effect of specific Mcl-1 small interference RNA (siRNA) on the proliferation and chemosensitivity of U-937 AML cell to etoposide. The siRNA transfection was conducted using Lipofectamine 2000. Quantitative real-time RT-PCR (qRT-PCR) and Western blot analysis were employed to measure the expression levels of mRNA and protein, respectively. To evaluate tumor cell growth after siRNA transfection, Trypan blue exclusion assay was conducted. The cytotoxic effects of siRNA and etoposide were determined using MTT assay on their own and in combination. DNA-histone ELISA and annexin-V/FITC assays were performed to study the apoptosis. Mcl-1 siRNA transfection significantly blocked the expression of Mcl-1 mRNA and protein in a time-dependent manner, leading to a strong growth inhibition and enhanced apoptosis (P less than 0.05). Furthermore, pretreatment with Mcl-1 siRNA, synergistically enhanced the cytotoxic and apoptotic effects of etoposide (P less than 0.05). Our results demonstrated that Mcl-1 plays a fundamental role in the survival and resistance of U-937 cells to etoposide. Therefore, Mcl-1 can be considered an attractive target in gene therapy of AML patients and siRNA-mediated silencing of this gene may be a novel strategy in AML treatment.

Matched MeSH terms: Reverse Transcriptase Polymerase Chain Reaction
Fulltext Molecular characterization of two Malaysian patients with Wiskott-Aldrich syndrome

Baharin MF, Kader Ibrahim SB, Yap SH, Abdul Manaf AM, Mat Ripen A, Dhaliwal JS

Malays J Pathol, 2015 Aug;37(2):153-8.
PMID: 26277674 MyJurnal

The Wiskott-Aldrich Syndrome (WAS) is an X-linked immunodeficiency condition characterized by microthrombocytopenia, eczema and recurrent infections. It is caused by mutations in the Wiskott-Aldrich Syndrome protein (WASP) gene. We investigated two Malay boys who presented with congenital thrombocytopenia, eczema and recurrent infections. Here we report two cases of WASP mutation in Malaysia from two unrelated families. One had a novel missense mutation in exon 1 while the other had a nonsense mutation in exon 2. Both patients succumbed to diseaserelated complications. A differential diagnosis of WAS should be considered in any male child who present with early onset thrombocytopenia, especially when this is associated with eczema and recurrent infections.

Matched MeSH terms: Reverse Transcriptase Polymerase Chain Reaction
Reversible thermo-pneumatic valves on centrifugal microfluidic platforms

Aeinehvand MM, Ibrahim F, Harun SW, Kazemzadeh A, Rothan HA, Yusof R, et al.

Lab Chip, 2015 Aug 21;15(16):3358-69.
PMID: 26158597 DOI: 10.1039/c5lc00634a

Centrifugal microfluidic systems utilize a conventional spindle motor to automate parallel biochemical assays on a single microfluidic disk. The integration of complex, sequential microfluidic procedures on these platforms relies on robust valving techniques that allow for the precise control and manipulation of fluid flow. The ability of valves to consistently return to their former conditions after each actuation plays a significant role in the real-time manipulation of fluidic operations. In this paper, we introduce an active valving technique that operates based on the deflection of a latex film with the potential for real-time flow manipulation in a wide range of operational spinning speeds. The reversible thermo-pneumatic valve (RTPV) seals or reopens an inlet when a trapped air volume is heated or cooled, respectively. The RTPV is a gas-impermeable valve composed of an air chamber enclosed by a latex membrane and a specially designed liquid transition chamber that enables the efficient usage of the applied thermal energy. Inputting thermo-pneumatic (TP) energy into the air chamber deflects the membrane into the liquid transition chamber against an inlet, sealing it and thus preventing fluid flow. From this point, a centrifugal pressure higher than the induced TP pressure in the air chamber reopens the fluid pathway. The behaviour of this newly introduced reversible valving system on a microfluidic disk is studied experimentally and theoretically over a range of rotational frequencies from 700 RPM to 2500 RPM. Furthermore, adding a physical component (e.g., a hemispherical rubber element) to induce initial flow resistance shifts the operational range of rotational frequencies of the RTPV to more than 6000 RPM. An analytical solution for the cooling of a heated RTPV on a spinning disk is also presented, which highlights the need for the future development of time-programmable RTPVs. Moreover, the reversibility and gas impermeability of the RTPV in the microfluidic networks are validated on a microfluidic disk designed for performing liquid circulation. Finally, an array of RTPVs is integrated into a microfluidic cartridge to enable sequential aliquoting for the conversion of dengue virus RNA to cDNA and the preparation of PCR reaction mixtures.

Matched MeSH terms: Reverse Transcriptase Polymerase Chain Reaction
Fulltext Development of a human salivary gland organoid model

Zulaiha A. Rahman, Colin D. Bingle, Lynne Bingle

Malaysian Journal of Medicine and Health Sciences, 2019;15(107):1-1.
MyJurnal

Introduction: Currently, organoid technology provides a useful tool for modelling human organ development and pathologies in vitro. Salivary gland (SG) organoids developed from mice SG cells display self-organizing properties closely mimic the native organ. Thus, this study would like to investigate the potential of this organoid system to de-velop a human salivary gland in vitro. Methods: Organoids were developed from biopsy samples of normal human sublingual gland tissue. Cells were isolated and cultured in Matrigel at an Air Liquid Interface (ALI) for up to 14 days in an enriched media supplementing with Wnt-3A, R-spondin1, EGF, and FGF2. Specific differentiation factors like TGFβ, BMP, and LIMK inhibitors were added to enriched media for further differentiation studies. Haematoxylin and eosin-stained sections of the cultures were used to visualise growth. RT-PCR, immunohistochemistry and immunoflu-orescence were used to determine the differential expression of cell-specific markers. Results: Human SG organoids developed when the cells were grown in Matrigel at ALI in a defined culture system. The addition of TGFβ inhibitor and all the inhibitors (TGFβ, BMP and LIMK) to the culture media affected SG organoids development by displaying distinct characteristics that closely resemble native glands and expressed specific cell-type markers; BPIFA2, AQP5, CK5 and E-cadherin. The inhibition of BMP signalling demonstrated SG organoids growth more into ductal-like struc-tures and expressed ductal cell marker, CK7. While LIM kinase inhibition signalling showed significantly higher of amylase activity assay. Conclusion: This study certainly offers valuable insight into determining the optimal culture conditions for developing human SG organoids.

Matched MeSH terms: Reverse Transcriptase Polymerase Chain Reaction
Fulltext Advances in the Diagnosis of Foot-and-Mouth Disease

Wong CL, Yong CY, Ong HK, Ho KL, Tan WS

Front Vet Sci, 2020;7:477.
PMID: 32974392 DOI: 10.3389/fvets.2020.00477

Foot-and-mouth disease (FMD) is a devastating livestock disease caused by foot-and-mouth disease virus (FMDV). Outbreaks of this disease in a country always result in conspicuous economic losses to livestock industry and subsequently lead to serious socioeconomic damages due to the immediate imposition of trade embargo. Rapid and accurate diagnoses are imperative to control this infectious virus. In the current review, enzyme-linked immunosorbent assay (ELISA)-based methods used in FMD diagnosis are extensively reviewed, particularly the sandwich, liquid-phase blocking, and solid-phase competition ELISA. The differentiation of infected animals from vaccinated animals using ELISA-based methods is also highlighted, in which the role of 3ABC polyprotein as a marker is reviewed intensively. Recently, more studies are focusing on the molecular diagnostic methods, which detect the viral nucleic acids based on reverse transcription-polymerase chain reaction (RT-PCR) and RT-loop-mediated isothermal amplification (RT-LAMP). These methods are generally more sensitive because of their ability to amplify a minute amount of the viral nucleic acids. In this digital era, the RT-PCR and RT-LAMP are progressing toward the mobile versions, aiming for on-site FMDV diagnosis. Apart from RT-PCR and RT-LAMP, another diagnostic assay specifically designed for on-site diagnosis is the lateral flow immunochromatographic test strips. These test strips have some distinct advantages over other diagnostic methods, whereby the assay often does not require the aid of an external device, which greatly lowers the cost per test. In addition, the on-site diagnostic test can be easily performed by untrained personnel including farmers, and the results can be obtained in a few minutes. Lastly, the use of FMDV diagnostic assays for progressive control of the disease is also discussed critically.

Matched MeSH terms: Reverse Transcriptase Polymerase Chain Reaction
Fulltext Echovirus serotypes circulating in Malaysia from 2014 to 2019

Manisya Zauri Abdul Wahid, Tengku Rogayah T. Abd. Rashid, Hariyati Md. Ali, Hamadah Mohd Shafiff, Mohd. Shamsul Samsuddin, Syarifah Nur Aisyatun Syed Mohd Salleh, et al.

Malaysian Journal of Medicine and Health Sciences, 2019;15(106):91-91.
MyJurnal

Introduction:Echoviruses are Enteroviruses (HEVs) that infect millions of people annually worldwide, primarily paediatrics. These viruses are frequently associated with outbreaks and sporadic cases of viral meningitis, enceph-alitis, paralysis, myocarditis, severe systemic infections; and hand-foot-mouth disease. This study is a retrospective study to identify Echovirus serotypes circulating in Malaysia from January 2014 to June 2019, and their roles in outbreak prediction. This study investigated the Echovirus serotypes circulating in Malaysia from January 2014 to June 2019. Methods: A total of 13,855 inpatient samples consisting respiratory secretion, stool, tissue and body fluid from around the country were received by the Virology Unit, Institute for Medical Research between January 2014 and June 2019. The presence of HEV’s RNA was detected by qPCR. The identified positive sample was further isolated by cell culture and identified by Immunofluorescence Assay (IFA). The IFA positive samples were subjected to amplification of partial VP4 gene by RT-PCR, and proceeded to Sanger sequencing for phylogenetic analysis by using ChromasPro and MEGA Software. The sequence generated were analysed by BLAST to confirm the sequence serotypes generated. Results: Echovirus genome was detected in 0.35% (37/10,681) of the patients. The circulating Echovirus subtypes in Malaysia between January 2014 and June 2019 were Echo-11 (43.2%; 16/37), followed by Echo-6 (16.2%; 6/37); 8.1% (3/37) of Echo-7 and Echo-13, respectively. Meanwhile, other types of Echoviruses (24.3%; 9/37) such as Echo 3-5, Echo-14, Echo-16, Echo-18, Echo-25 and Echo-30 were also detected in this study. Conclusion: In this study, it has been found that Echovirus 11 serotype is the most predominant Echovirus serotype circulating in Malaysia between January 2014 and June 2019. It has been reported to cause severe diseases, such as aseptic meningitis. Therefore, the identification of circulating serotypes of Echovirus is critical to predict the Echovi-rus outbreak and to reduce the risk of developing severe disease in Malaysia.

Matched MeSH terms: Reverse Transcriptase Polymerase Chain Reaction
Fulltext Early Odontogenic Differentiation of Dental Pulp Stem Cells Treated with Nanohydroxyapatite-Silica-Glass Ionomer Cement

Siew Ching H, Thirumulu Ponnuraj K, Luddin N, Ab Rahman I, Nik Abdul Ghani NR

Polymers (Basel), 2020 Sep 17;12(9).
PMID: 32957636 DOI: 10.3390/polym12092125

This study aimed to investigate the effects of nanohydroxyapatite-silica-glass ionomer cement (nanoHA-silica-GIC) on the differentiation of dental pulp stem cells (DPSCs) into odontogenic lineage. DPSCs were cultured in complete Minimum Essential Medium Eagle-Alpha Modification (α-MEM) with or without nanoHA-silica-GIC extract and conventional glass ionomer cement (cGIC) extract. Odontogenic differentiation of DPSCs was evaluated by real-time reverse transcription polymerase chain reaction (rRT-PCR) for odontogenic markers: dentin sialophosphoprotein (DSPP), dentin matrix protein 1 (DMP1), osteocalcin (OCN), osteopontin (OPN), alkaline phosphatase (ALP), collagen type I (COL1A1), and runt-related transcription factor 2 (RUNX2) on day 1, 7, 10, 14, and 21, which were normalized to the house keeping gene glyceraldehyde-3-phosphate dehydrogenase (GAPDH). Untreated DPSCs were used as a control throughout the study. The expressions of DSPP and DMP1 were higher on days 7 and 10, that of OCN on day 10, those of OPN and ALP on day 14, and that of RUNX2 on day 1; COL1A1 exhibited a time-dependent increase from day 7 to day 14. Despite the above time-dependent variations, the expressions were comparable at a concentration of 6.25 mg/mL between the nanoHA-silica-GIC and cGIC groups. This offers empirical support that nanoHA-silica-GIC plays a role in the odontogenic differentiation of DPSCs.

Matched MeSH terms: Reverse Transcriptase Polymerase Chain Reaction
Fulltext Molecular investigation of feline coronavirus (FCOV) in local pet cats

Hoong, L.W., Yasmin, A.R., Mummoorthy, K., Arshad, S.S., Omar, A.R., Anand, P., et al.

Jurnal Veterinar Malaysia, 2019;31(2):13-18.
MyJurnal

Feline coronavirus (FCoV) infection is a very common in cat population. FCoV is further classified into two biotypes namely feline enteric coronavirus (FECV) and mutated feline infectious peritonitis virus (FIPV), in which FIPV causes a fatal immune complex disease by changing the tropism from enterocytes to monocytes. Previous studies on molecular detection of FCoV in cats were carried out in catteries but limited study investigate the presence of FCoV antigen in local pet cats. By considering this fact, this study aims to detect FCoV antigen via RT-PCR assay in local pet cats and to compare the similarity of the identified FCoV strain with previous related virus by phylogenetic analysis. By using convenience sampling, rectal swabs and buffy coat were collected from 16 clinically ill pet cats and 5 healthy pet cats. Viral RNA was extracted and subjected to one-step RT-PCR, targeting polymerase gene. Only one out of 21 fecal samples was positive for FCoV and none from buffy coat samples. Phylogenetic analysis revealed that the identified positive sample was highly homologous, up to 95%, to FCoV strain from Netherlands and South Korea on partial sequence of polymerase gene. In conclusion, this study detected FCoV antigen in local pet cats from fecal samples while negative detection from fecal and buffy coat samples could not completely rule out the possibilities of FCoV infection due to the complexity of the virus diagnosis that require multiple series of analysis.

Matched MeSH terms: Reverse Transcriptase Polymerase Chain Reaction
p16 gene expression in basal cell carcinoma

Eshkoor SA, Ismail P, Rahman SA, Oshkour SA

Arch Med Res, 2008 Oct;39(7):668-73.
PMID: 18760195 DOI: 10.1016/j.arcmed.2008.06.003

Basal cell carcinoma (BCC) develops predominantly in sun-exposed skin in fair-skinned individuals prone to sunburn. BCC typically occurs in adults. High exposure to ultraviolet (UV) radiation increases rate of developing BCC, a slowly growing tumor that occurs in hair-growing squamous epithelium and rarely metastasizes. In genetic studies, BCC patients have cell-cycle abnormalities of different parts of the signaling pathway. Retinoblastoma regulatory pathway is important in cell cycle arrest. In this pathway, p16INK4a, an inhibitor of Rb pathway, binds to CDK4 and CDK6 competitively with cyclin D1 to prevent phosphorylation of tumor suppressor pRB gene. Alteration of this pathway contributes to development of human cancers and also is effective in skin cancers. In this study, we analyzed mRNA expression using in situ RT-PCR and the role of immunohistochemical expression of p16INK4a in BCC.

Matched MeSH terms: Reverse Transcriptase Polymerase Chain Reaction
The distribution of important sero-complexes of flaviviruses in Malaysia

Kumar K, Arshad SS, Toung OP, Abba Y, Selvarajah GT, Abu J, et al.

Trop Anim Health Prod, 2019 Mar;51(3):495-506.
PMID: 30604332 DOI: 10.1007/s11250-018-01786-x

Flaviviruses (FVs) are arthropod-borne viruses of medical and veterinary importance. Numerous species of FVs have been isolated from various host; mainly humans, animals, ticks, and mosquitoes. Certain FVs are extremely host-specific; at the same time, some FVs can infect an extensive range of species. Based on published literatures, 11 species of FVs have been detected from diverse host species in Malaysia. In humans, dengue virus and Japanese encephalitis virus have been reported since 1901 and 1942. In animals, the Batu Cave virus, Sitiawan virus, Carey Island, Tembusu virus, Duck Tembusu virus, and Japanese encephalitis viruses were isolated from various species. In mosquitoes, Japanese encephalitis virus and Kunjin virus were isolated from Culex spp., while Zika virus and Jugra virus were isolated from Aedes spp. In ticks, the Langat virus was isolated from Ixodes spp. One of the major challenges in the diagnosis of FVs is the presence of sero-complexes as a result of cross-reactivity with one or more FV species. Subsequently, the distribution of specific FVs among humans and animals in a specific population is problematic to assess and often require comprehensive and thorough analyses. Molecular assays such as quantitative reverse transcriptase polymerase chain reaction (qRT-PCR) and digital droplet RT-PCR (ddRT-PCR) have been used for the differentiation of flavivirus infections to increase the accuracy of epidemiological data for disease surveillance, monitoring, and control. In situations where sero-complexes are common in FVs, even sensitive assays such as qRT-pCR can produce false positive results. In this write up, an overview of the various FV sero-complexes reported in Malaysia to date and the challenges faced in diagnosis of FV infections are presented.

Matched MeSH terms: Reverse Transcriptase Polymerase Chain Reaction
Emergence of Getah Virus Infection in Horse With Fever in China, 2018

Lu G, Ou J, Ji J, Ren Z, Hu X, Wang C, et al.

Front Microbiol, 2019;10:1416.
PMID: 31281304 DOI: 10.3389/fmicb.2019.01416

Getah virus (GETV) is a mosquito-borne virus that was first determined in Malaysia in 1955, and can infect humans and multiple other mammals. GETV infection in horses has been reported in Japan and India, and causes great economic losses. In China, GETV has been identified in mosquitoes, pigs, foxes, and cattle with a wide geographical distribution, but has not been detected in horses. In August 2018, a sudden onset of fever was observed in racehorse in an equestrian training center in Guangdong Province in southern China. Blood samples were collected from the sick horse, and PCR/RT-PCR analysis was performed to screen for equine viral pathogens associated with fever. The results indicated that the samples were GETV RNA positive. After RT-PCR, sequencing, and assembly, the genome of the first Chinese horse-derived GETV strain, GZ201808, was obtained. Compared with the genome sequences of other GETV strains, twelve unique nucleotide substitutions were observed in GZ201808. The genome of GZ201808 had the highest genetic identity (99.6%) with AH9192, which was detected in pigs in China in 2017. Phylogenetic analysis indicated that GZ201808 clustered in Group III, and was located in an independent branch distant from other horse-derived GETV strains, indicating a unique evolutionary pattern of GZ201808. This study first determined and described the disease course of horse infected with GETV in China, sequenced and characterized the genome of the field horse-derived GETV strain, and therefore presented an unequivocal report of GETV infection in horses in China.

Matched MeSH terms: Reverse Transcriptase Polymerase Chain Reaction
Fulltext Hepatitis C infection and detection of antibodies, RNA and genotypes among female healthcare workers in Baghdad

Waqar, A.K., Nik Shamsidah N.I., Nor Aini M.N., Waqar, Abd Alqahar Al –Kubaisy

JUMMEC, 2018;21(1):14-20.
MyJurnal

Background: Hepatitis C Virus (HCV) is a major public health problem worldwide. About 130- 200 million people
are infected with HCV worldwide leading to 500,000 deaths annually (WHO 2014). Healthcare workers (HCWs)
have played an important role in the transmission of HCV infection, either as victims or as sources of infection.
Objectives: To determine the prevalence of HCV, antibodies (Abs) RNA and genotypes among the female HCWs
in Baghdad and to identify whether HCWs were infective or only infected.
Subjects and Methods: A cross-sectional study involving 1001 women attending 17 health care centres in
Baghdad, Iraq, was carried out. Information on type and duration of their occupation was obtained. HCV Abs
(anti-HCV) were tested using a third generation enzyme immunoassay (EIA-3) and immunoblot assay (Lia
Tek-111). Molecular analysis using RT-PCR and DNA enzyme immunoassay (DEIA) for HCV-RNA and genotype
detections were carried out for 63 serum samples.
Results: Only 160/1001 (15.98%) were HCWs. Anti-HCV and HCV- RNA seroprevalence were significantly higher
(6.37%, p=0.0057, 88.83%, p= 0.011 respectively) among HCWs than non HCWs. HCWs were at a significantly
higher risk of exposure to HCV infection (OR=2.75, 95% C.I. =1.31-5.79). There was no significant association
between HCV genotypes and the HCWs. HCV-4 showed higher expression (62.5%) among HCWs.
Conclusion: Female HCWs were infective and infected with HCV, thus there is a need for medical equipment
to be sterilized and cleaned thoroughly.

Matched MeSH terms: Reverse Transcriptase Polymerase Chain Reaction
Fulltext Isolation and molecular characterization of coxsackievirus A6 and coxsackievirus A16 from a case of recurrent Hand, Foot and Mouth Disease in Mumbai, Maharashtra, India, 2018

Saxena VK, Pawar SD, Qureshi THIH, Surve P, Yadav P, Nabi F, et al.

Virusdisease, 2020 Mar;31(1):56-60.
PMID: 32206699 DOI: 10.1007/s13337-020-00567-1

Hand, Foot and Mouth Disease (HFMD) is caused by multiple Enterovirus (EV) serotypes mainly coxsackievirus A6 (CV-A6), coxsackievirus A16 (CV-A16) and Enterovirus 71 (EV-A71). Recurrent HFMD infections are rarely reported. An unusual rise in HFMD cases was reported in Mumbai during May-June 2018. Stool and throat swab specimens were referred from seven children from two hospitals for laboratory diagnosis. The age group of cases ranged from 9 months to 5 years with median age 13 months. Out of seven cases, three were males and four females. One 13-month-old female case was reported twice within 21 days. Stool, throat swab specimens were tested by pan enterovirus RT-PCR and also by virus isolation using human rhabdomyosarcoma cell line for detection of Enteroviruses. Out of seven HFMD cases, CV-A6 and CV-A16 viruses were isolated from five and two cases respectively. The phylogenetic analysis of CV-A6 viruses showed their similarity with CV-A6 viruses from Finland and China, whereas the two CV-A16 isolates showed similarity with those from Japan, France, China, Sarawak and Thailand. For the recurrent HFMD case, CV-A6 and CV-A16 were isolated from the stool specimens collected during the first and second episodes, respectively. There are no reports of isolation and molecular characterization of CV-A6 and CV-A16 viruses from recurrent HFMD cases. The present study reports molecular characterization of two Enterovirus serotypes CV-A6 and CV-A16 from a recurrent HFMD case, highlighting need of virological and molecular surveillance of HFMD.

Matched MeSH terms: Reverse Transcriptase Polymerase Chain Reaction
Fulltext Pre-surgical COVID-19 swabs in surgical patients: An institutional experience in a middle income country

Xavier RG, Roslani AC, Draman Yusof MR, Ng DS, Govindaraju R, Singh S, et al.

Asian J Surg, 2021 03;44(3):560-561.
PMID: 33627224 DOI: 10.1016/j.asjsur.2020.11.028
Matched MeSH terms: Reverse Transcriptase Polymerase Chain Reaction
Fulltext Molecular detection of feline leukemia virus in clinically ill cats in Klang Valley, Malaysia

Mummoorthy K, Yasmin AR, Arshad SS, Omar AR, Nur-Fazila SH, Anand P, et al.

Vet World, 2021 Feb;14(2):405-409.
PMID: 33776305 DOI: 10.14202/vetworld.2021.405-409

Background and Aim: Feline leukemia virus (FeLV) is classified as Retroviridae gammaretrovirus. FeLV occurs worldwide, including Malaysia. Thus far, only one decade-old study on molecular characterization of Malaysian FeLV isolates exists, which resulted in a scarcity of updated information of current FeLV isolates circulating in Malaysia. This study was conducted to determine the status of FeLV in clinically ill cats and to study the molecular characterization and phylogenetic relatedness of the current isolates.
Materials and Methods: Convenience sampling was performed in 20 cats from the Gasing Veterinary Hospital in Selangor. Plasma and saliva samples were collected from 15 clinically ill cats and 5 healthy cats subjected to one-step reverse transcription-polymerase chain reaction with primers targeting a highly conserved gene of U3-LTR-gag.
Results: Two clinically ill cats' plasma and saliva samples tested positive for FeLV RNA. Partial nucleotide sequencing and phylogenetic analysis revealed that the current isolates were 94-99% homologous to the previous Malaysian and Japanese FeLV isolates.
Conclusion: Current FeLV isolates from this study displayed higher similarity with the previous Malaysian isolates, signifying that a similar FeLV strain circulated among the cat population in Selangor.

Matched MeSH terms: Reverse Transcriptase Polymerase Chain Reaction
Fulltext Milestone of polio Environmental Surveillance in Malaysia conjoining with the Polio Global Eradication Initiative

Kamal Haikal Mat Rabi, Amry Khursany Ismail, Mohd Samsul Samsuddin, Manisha Zauri Abdul Wahid, Zarina Mohd Zamawi, Ravindran Thayan

Malaysian Journal of Medicine and Health Sciences, 2019;15(106):78-78.
MyJurnal

Introduction: Poliomyelitis is an incapacitating and highly infectious disease which effect mostly young children. It is caused by one of the three serotypes of polioviruses (PV) and transmitted through faecal-oral route hence making the disease quite pertinent to the lower and middle class society or under-immunized population. This surveillance is one of the strategy included by WHO in the “Eradication, Integration and Certification: The Endgame Strategy 2019-2023” as a supplement to AFP surveillance by which it could be more sensitive to detect low circulation of WPV and circulating vaccine derived poliovirus (cVDPV). Methods: Routine collection and testing of representative environmental surveillance are carried out in the National Polio Laboratory. The specimens are collected from designated locations draining target populations at increased risk of poliovirus transmission using the grab method once a month and processed according to WHO standard protocol. Polioviruses were identified by real time reverse transcriptase polymerase chain reaction (rRT-PCR) for intratypic differentiation (ITD) and vaccine derived poliovirus (VDPV) whereas non-polio enteroviruses (NPEVs) were identified by PCR and sequencing. Results: From 2012 to 2019, results showed various isolation of PVs and NPEVs. A total of 12 sewage disposal plants located in urban highly populated areas in Kuala Lumpur (3), Selangor (5), Sabah (3 ) and Negeri Sembilan (1) were investigated. A total of 22 Sabin-like PVs were isolated consisting of 3 PV1, 8 PV2 and 11 PV3 thus indicated that in Malaysia even though PVs were existed in environment, but all of them were Sabin-Like viruses and no evidence of imported WPV or VDPV in the sampling sites. Conclusion: Even though Malaysia has been declared as WPV free country in 2000, Environmental Surveillance is very important and crucial in detecting the introduction and silent circulation of WPV and cVDPV before the virus reaches the community.

Matched MeSH terms: Reverse Transcriptase Polymerase Chain Reaction
Genetic Diversity of Recent Infectious Bursal Disease Viruses Isolated From Vaccinated Poultry Flocks in Malaysia

Aliyu HB, Hair-Bejo M, Omar AR, Ideris A

Front Vet Sci, 2021;8:643976.
PMID: 33959650 DOI: 10.3389/fvets.2021.643976

Vaccination is an essential component in controlling infectious bursal disease (IBD), however, there is a lack of information on the genetic characteristics of a recent infectious bursal disease virus (IBDV) that was isolated from IBD vaccinated commercial flocks in Malaysia. The present study investigated 11 IBDV isolates that were isolated from commercial poultry farms. The isolates were detected using reverse transcription-polymerase chain reaction (RT-PCR) targeting the hypervariable region (HVR) of VP2. Based on the HVR sequences, five isolates (IBS536/2017, IBS624/2017, UPM766/2018, UPM1056/2018, and UPM1432/2019) were selected for whole-genome sequencing using the MiSeq platform. The nucleotide and amino acid (aa) sequences were compared with the previously characterized IBDV strains. Deduced aa sequences of VP2HVR revealed seven isolates with 94-99% aa identity to very virulent strains (genogroup 3), two isolates with 97-100% aa identity to variant strains (genogroup 2), and two strains with 100% identity to the vaccine strain (genogroup 1) of IBDV. The phylogenetic analysis also showed that the isolates formed clusters with the respective genogroups. The characteristic motifs 222T, 249K, 286I, and 318D are typical of the variant strain and were observed for UPM1219/2019 and UPM1432/2019. In comparison, very virulent residues such as 222A, 249Q, 286T, and 318G were found for the vvIBDV, except for the UPM1056/2018 strain with a A222T substitution. In addition, the isolate has aa substitutions such as D213N, G254D, S315T, S317R, and A321E that are not commonly found in previously reported vvIBDV strains. Unlike the other vvIBDVs characterized in this study, UPM766/2018 lacks the MLSL aa residues in VP5. The aa tripeptides 145/146/147 (TDN) of VP1 were conserved for the vvIBDV, while a different motif, NED, was observed for the Malaysian variant strain. The phylogenetic tree showed that the IBDV variant clustered with the American and Chinese variant viruses and are highly comparable to the novel Chinese variants, with 99.9% identity. Based on the sequences and phylogenetic analyses, this is the first identification of an IBDV variant being reported in Malaysia. Further research is required to determine the pathogenicity of the IBDV variant and the protective efficacy of the current IBD vaccines being used against the virus.

Matched MeSH terms: Reverse Transcriptase Polymerase Chain Reaction
Panspecies molecular assays detect viral pathogens missed by real-time PCR/reverse-transcriptase PCR among pneumonia patients, Sarawak, Malaysia

Fieldhouse JK, Bailey ES, Toh TH, Hii KC, Mallinson KA, Ting J, et al.

Trop Dis Travel Med Vaccines, 2020;6:13.
PMID: 32817802 DOI: 10.1186/s40794-020-00114-2

Background: In a year-long pneumonia etiology study conducted June 2017 to May 2018 in Sarawak, Malaysia, 599 patients' nasopharyngeal swab specimens were studied with real-time polymerase chain reaction (rPCR)/ reverse-transcription (rRT-PCR) assays for respiratory pathogens known to contribute to the high burden of lower respiratory tract infections. The study team sought to compare real-time assay results with panspecies conventional molecular diagnostics to compare sensitivities and learn if novel viruses had been missed.
Methods: Specimens were studied for evidence of adenovirus (AdV), enterovirus (EV) and coronavirus (CoV) with panspecies gel-based nested PCR/RT-PCR assays. Gene sequences of specimens positive by panspecies assays were sequenced and studied with the NCBI Basic Local Alignment Search Tool software.
Results: There was considerable discordance between real-time and conventional molecular methods. The real-time AdV assay found a positivity of 10.4%; however, the AdV panspecies assay detected a positivity of 12.4% and the conventional AdV-Hexon assay detected a positivity of 19.6%. The CoV and EV panspecies assays similarly detected more positive specimens than the real-time assays, with a positivity of 7.8% by the CoV panspecies assay versus 4.2% by rRT-PCR, and 8.0% by the EV panspecies assay versus 1.0% by rRT-PCR. We were not able to ascertain virus viability in this setting. While most discordance was likely due to assay sensitivity for previously described human viruses, two novel, possible zoonotic AdV were detected.
Conclusions: The observed differences in the two modes of amplification suggest that where a problem with sensitivity is suspected, real-time assay results might be supplemented with panspecies conventional PCR/RT-PCR assays.

Matched MeSH terms: Reverse Transcriptase Polymerase Chain Reaction

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