Displaying publications 241 - 260 of 261 in total

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  1. Chan YF, AbuBakar S
    Virol J, 2005;2:74.
    PMID: 16122396
    At least three different EV-71 subgenotypes were identified from an outbreak in Malaysia in 1998. The subgenotypes C2 and B4 were associated with the severe and fatal infections, whereas the B3 virus was associated with mild to subclinical infections. The B3 virus genome sequences had >= 85% similarity at the 3' end to CV-A16. This offers opportunities to examine if there are characteristic similarities and differences in virulence between CV-A16, EV-71 B3 and EV-71 B4 and to determine if the presence of the CV-A16-liked genes in EV-71 B3 would also confer the virus with a CV-A16-liked neurovirulence in mice model infection.
    Matched MeSH terms: Encephalitis, Viral/virology*
  2. Adams SC, Broom AK, Sammels LM, Hartnett AC, Howard MJ, Coelen RJ, et al.
    Virology, 1995 Jan 10;206(1):49-56.
    PMID: 7530394
    Previous studies have found Kunjin (KUN) virus isolates from within Australia to be genetically homogenous and that the envelope protein of the type strain (MRM61C) was unglycosylated and lacked a potential glycosylation site. We investigated the extent of antigenic variation between KUN virus isolates from Australia and Sarawak using an immunoperoxidase assay and a panel of six monoclonal antibodies. The glycosylation status of the E protein of each virus was also determined by N glycosidase F (PNGase F) digestion and limited sequence analysis. The results showed that KUN viruses isolated within Australia oscillated between three antigenic types defined by two epitopes whose expression was influenced by passage history and host cell type. In contrast an isolate from Sarawak formed a stable antigenic type that was not influenced by passage history and was distinct from all Australian isolates. PNGase F digestions of KUN isolates indicated that 19 of the 33 viruses possessed a glycosylated E protein. Nucleotide sequence of the 5' third of the E gene of selected KUN isolates revealed that a single base change in PNGase F sensitive strains changed the tripeptide N-Y-F (amino acids 154-156 of the published sequence) to the potential glycosylation site N-Y-S. Further analysis revealed that passage history also had a significant influence on glycosylation.
    Matched MeSH terms: Encephalitis Viruses, Japanese/immunology*
  3. Jiang H, Bai L, Ji L, Bai Z, Su J, Qin T, et al.
    J Virol, 2020 07 16;94(15).
    PMID: 32461319 DOI: 10.1128/JVI.00294-20
    Japanese encephalitis virus (JEV) infection alters microRNA (miRNA) expression in the central nervous system (CNS). However, the mechanism contributing to miRNA regulation in the CNS is not known. We discovered global degradation of mature miRNA in mouse brains and neuroblastoma (NA) cells after JEV infection. Integrative analysis of miRNAs and mRNAs suggested that several significantly downregulated miRNAs and their targeted mRNAs were clustered into an inflammation pathway. Transfection with miRNA 466d-3p (miR-466d-3p) decreased interleukin-1β (IL-1β) expression and inhibited JEV replication in NA cells. However, miR-466d-3p expression increased after JEV infection in the presence of cycloheximide, indicating that viral protein expression reduced miR-466d-3p expression. We generated all the JEV coding proteins and demonstrated NS3 helicase protein to be a potent miRNA suppressor. The NS3 proteins of Zika virus, West Nile virus, and dengue virus serotype 1 (DENV-1) and DENV-2 also decreased miR-466d-3p expression. Results from helicase-blocking assays and in vitro unwinding assays demonstrated that NS3 could unwind pre-miR-466d and induce miRNA dysfunction. Computational models and an RNA immunoprecipitation assay revealed arginine-rich domains of NS3 to be crucial for pre-miRNA binding and degradation of host miRNAs. Importantly, site-directed mutagenesis of conserved residues in NS3 revealed that R226G and R202W reduced the binding affinity and degradation of pre-miR-466d. These results expand the function of flavivirus helicases beyond unwinding duplex RNA to degrade pre-miRNAs. Hence, we revealed a new mechanism for NS3 in regulating miRNA pathways and promoting neuroinflammation.IMPORTANCE Host miRNAs have been reported to regulate JEV-induced inflammation in the CNS. We found that JEV infection could reduce expression of host miRNA. The helicase region of the NS3 protein bound specifically to miRNA precursors and could lead to incorrect unwinding of miRNA precursors, thereby reducing the expression of mature miRNAs. This observation led to two major findings. First, our results suggested that JEV NS3 protein induced miR-466d-3p degradation, which promoted IL-1β expression and JEV replication. Second, arginine molecules on NS3 were the main miRNA-binding sites, because we demonstrated that miRNA degradation was abolished if arginines at R226 and R202 were mutated. Our study provides new insights into the molecular mechanism of JEV and reveals several amino acid sites that could be mutated for a JEV vaccine.
    Matched MeSH terms: Encephalitis Virus, Japanese/physiology*
  4. Sherrini BA, Chong TT
    Med J Malaysia, 2014 Aug;69 Suppl A:103-11.
    PMID: 25417957
    Between September 1998 to May 1999, Malaysia and Singapore were hit by an outbreak of fatal encephalitis caused by a novel virus from the paramyxovirus family. This virus was subsequently named as Nipah virus, after the Sungei Nipah village in Negeri Sembilan, where the virus was first isolated. The means of transmission was thought to be from bats-topigs and subsequently pigs-to-human. Since 2001, almost yearly outbreak of Nipah encephalitis has been reported from Bangladesh and West Bengal, India. These outbreaks were characterized by direct bats-to-human, and human-to-human spread of infection. Nipah virus shares many similar characteristics to Hendra virus, first isolated in an outbreak of respiratory illness involving horses in Australia in 1994. Because of their homology, a new genus called Henipavirus (Hendra + Nipah) was introduced. Henipavirus infection is a human disease manifesting most often as acute encephalitis (which may be relapsing or late-onset) or pneumonia, with a high mortality rate. Pteropus bats act as reservoir for the virus, which subsequently lead to human spread. Transmission may be from consumption of food contaminated by bats secretion, contact with infected animals, or human-to-human spread. With wide geographical distribution of Pteropus bats, Henipavirus infection has become an important emerging human infection with worldwide implication.
    Matched MeSH terms: Encephalitis
  5. Masoomi Dezfooli S, Tan WS, Tey BT, Ooi CW, Hussain SA
    Biotechnol Prog, 2016 Jan-Feb;32(1):171-7.
    PMID: 26519022 DOI: 10.1002/btpr.2192
    Nipah virus (NiV) causes fatal respiratory illness and encephalitis in humans and animals. The matrix (M) protein of NiV plays an important role in the viral assembly and budding process. Thus, an access to the NiV M protein is vital to the design of viral antigens as diagnostic reagents. In this study, recombinant DNA technology was successfully adopted in the cloning and expression of NiV M protein. A recombinant expression cassette (baculovirus expression vector) was used to encode an N-terminally His-tagged NiV M protein in insect cells. A time-course study demonstrated that the highest yield of recombinant M protein (400-500 μg) was expressed from 107 infected cells 3 days after infection. A single-step purification method based on metal ion affinity chromatography was established to purify the NiV M protein, which successfully yielded a purity level of 95.67% and a purification factor of 3.39. The Western blotting and enzyme-linked immunosorbent assay (ELISA) showed that the purified recombinant M protein (48 kDa) was antigenic and reacted strongly with the serum of a NiV infected pig.
    Matched MeSH terms: Encephalitis
  6. Tan DS
    Med J Malaya, 1968 Dec;23(2):140-5.
    PMID: 4308419
    Matched MeSH terms: Encephalitis
  7. Kanchan Thadani, Chee Kok Yoon, Hanis Aminah John Mohamad, Norzaini Rose Mohd Zain, Chan Pek Har, Noor Jannah Ariffin
    MyJurnal
    Klüver-Bucy syndrome was first diagnosed in humans in 1955, after a group
    of people who had experienced temporal lobectomy. It is a rare
    neuropsychiatry disease and of which little is understood about its
    pathophysiological processes. Here we present a 60-year-old man seen in the
    outpatient psychiatric department in a tertiary hospital in Kuala Lumpur
    who presented to us with hyper sexuality, impulsivity, docility, amnesia and
    hyperphagia for the past 10 months. He was diagnosed with Herpes Simplex
    Virus with encephalitis 18 months ago and was shown to have bilateral
    meningoencephalitis of his temporal lobes. Thus, a diagnosis of Klüver-Bucy
    was made. We have taken a multi-disciplinary team approach to treat his
    illness and specific goals has been laid out in each discipline. A written
    consent has been taken by the patient and his family for the publication of
    this report.
    Matched MeSH terms: Encephalitis; Meningoencephalitis
  8. Ng WW, Cheong BMK
    Med J Malaysia, 2021 03;76(2):261-263.
    PMID: 33742642
    A previously well 21-year-old girl presented to Hospital Teluk Intan, Perak, Malaysia with a short history of fever, vomiting and altered sensorium. She was diagnosed with dengue encephalitis as her dengue NS-1 antigen was positive and her cerebrospinal fluid (CSF) dengue polymerase chain reaction (PCR) was positive with serotype DENV-2. She also had severe hyponatremia due to Syndrome of Inappropriate Antidiuretic Hormone Secretion (SIADH) which caused an episode of seizure. She recovered well with supportive management. SIADH and dengue encephalitis should be considered as one of the differential diagnosis in patients presenting with fever and altered sensorium especially in dengue endemic countries like Malaysia.
    Matched MeSH terms: Encephalitis
  9. Chattu VK, Kumar R, Kumary S, Kajal F, David JK
    J Family Med Prim Care, 2018 8 10;7(2):275-283.
    PMID: 30090764 DOI: 10.4103/jfmpc.jfmpc_137_18
    Nipah virus (NiV) encephalitis first reported in "Sungai Nipah" in Malaysia in 1999 has emerged as a global public health threat in the Southeast Asia region. From 1998 to 2018, more than 630 cases of NiV human infections were reported. NiV is transmitted by zoonotic (from bats to humans, or from bats to pigs, and then to humans) as well as human-to-human routes. Deforestation and urbanization of some areas have contributed to greater overlap between human and bat habitats resulting in NiV outbreaks. Common symptoms of NiV infection in humans are similar to that of influenza such as fever and muscle pain and in some cases, the inflammation of the brain occurs leading to encephalitis. The recent epidemic in May 2018 in Kerala for the first time has killed over 17 people in 7 days with high case fatality and highlighted the importance of One Health approach. The diagnosis is often not suspected at the time of presentation and creates challenges in outbreak detection, timely control measures, and outbreak response activities. Currently, there are no drugs or vaccines specific for NiV infection although this is a priority disease on the World Health Organization's agenda. Antivirals (Ribavirin, HR2-based fusion inhibitor), biologicals (convalescent plasma, monoclonal antibodies), immunomodulators, and intensive supportive care are the mainstay to treat severe respiratory and neurologic complications. There is a great need for strengthening animal health surveillance system, using a One Health approach, to detect new cases and provide early warning for veterinary and human public health authorities.
    Matched MeSH terms: Encephalitis
  10. Abdullah S, Lim KS, Wong WF, Tan HJ, Tan CT
    Neurology Asia, 2015;20(2):167-175.
    MyJurnal
    Background& Objective: Investigation modalities, such as MRI and CSF examination, are neither sensitive nor specific in the early phase of anti-NMDAR encephalitis. Nuclear imaging may be useful to monitor the response to treatment but limited by the availability.We aimed to determine the role of EEG as a tool for early diagnosis as well as a tool to assess disease progression and response to treatment. Methods: A total of 99 EEGsdone in 16 patients diagnosed with anti-NMDAR encephalitis throughout the course of illness, were reviewed retrospectively. The EEG changes were correlated with the clinical presentations and response to treatment. Sixteen EEGs of patients with schizophrenia and mood disorder, and 10 EEGs of patients with infective encephalitis were included as control. Results: EEGs performed during the psychiatric and cognitive dysfunctionphase in patient with anti-NMDAR encephalitis, showed diffuse background slowing in the delta-theta range in all the patients. Serial EEGs showed that the dominant background frequency improved with improvement in cognitive status. Nine patients had complete recovery with normalisation of the EEG abnormalities. Eight patients had their typical clinical seizure recorded during EEG monitoring, but only 2 (25.0%) with EEG correlation. Ten patients had status epilepticus (62.5%), 5 had EEG recorded during their status epilepticus, of which only one with EEG correlation (20.0%). Eleven patients had asymmetric background (68.8%), but only 1 has correlation with focal changes in the MRI brain (9.1%). Even though the EEGs of patients with infective encephalitis also showed background slowing, their CSF analysis was supportive of an infective cause. EEGs of patients with established psychiatric disorder were within normal limits.
    Conclusion: EEG abnormality has a good correlation with the degree of psychiatric and cognitive dysfunction in patient with anti-NMDAR encephalitis, and is useful in early diagnosis, monitoring the progress and the response to treatment. However, it has poor correlation with clinical seizures.
    Matched MeSH terms: Anti-N-Methyl-D-Aspartate Receptor Encephalitis
  11. Fadzilah Hj. Kamaludin
    MyJurnal
    There are disturbing trends of emerging and re-emerging infectious diseases, globally and locally thus giving it a real cause of concern. These include diseases by agents hitherto unknown in human such as Severe Acute Respiratory Syndrome (SARS) and Ebola; those that were purely zoonoses but had now affected man such as bovine spongioform encephalitis (BSE) in United Kingdom and avian influenza in Vietnam and Thailand; those that were thought to be eliminated but reappeared such as plague in India and those that begun to show reverse trends such as tuberculosis (TB) and malaria. Malaysia is no exception. Viral fever EV71, Chinkugunya, Conjunctivitis C24 variant or Nipah encephalitis were local examples of unknown or exotic infectious diseases occurring in recent years. In this age of globalization with expanding air travel and industrial trade, Malaysia is vulnerable to a wide array of new and resurgent infectious diseases. Apart from the direct health consequences on morbidity, mortality and its staggering cost, these infections also have far reaching implications upon sustainable development, psychosocial, economic, political and global security.
    Matched MeSH terms: Encephalitis
  12. Saini S, Thakur CJ, Kumar V, Tandon S, Bhardwaj V, Maggar S, et al.
    Mol Biol Res Commun, 2018 Sep;7(3):107-118.
    PMID: 30426028 DOI: 10.22099/mbrc.2018.29577.1322
    Current re-emergence of Nipah virus (NiV) in India caused 11 deaths so far and many patients were kept in quarantine. A thorough study of previous outbreaks occurred in Malaysia, Bangladesh and India represents cases with high rate of fatality due to acute encephalitis. Our work involves genome analysis of NiV for prediction of miRNAs and their targeted genes in human in order to understand encephalitis origin. Ab-intio program-VMir was used for initial screening of genome, obtained nine pre-miRNAs was analyzed by ViralMir to check for any pseudo pre-miRNAs. Eighteen functional mature miRNAs were extracted from pre-miRNAs by using Mature-Bayes tool, which targets 669 genes in human genome as retrieved by miRDB. Gene ontology terms by PANTHER provide important pathways in which target genes were involved like Axon guidance, T cell activation, and nicotinic acetylcholine receptor signaling. Significant outcome was obtained after NCBI Gene and OMIM database mining and literature search for predicted target genes. TLR3, TJP1, NOTCH2, FHL1, and GRIA3 target genes obtained showed their involvement in host defense, blood brain barrier, neurogenesis, mental retardation and encephalitis. To conclude, we predicted significant genes in human that can be inhibited by miRNAs of NiV and results in etiology of encephalitis.
    Matched MeSH terms: Encephalitis
  13. Anwar A, Chi Fung L, Anwar A, Jagadish P, Numan A, Khalid M, et al.
    Pathogens, 2019 Nov 22;8(4).
    PMID: 31766722 DOI: 10.3390/pathogens8040260
    T4 genotype Acanthamoeba are opportunistic pathogens that cause two types of infections, including vision-threatening Acanthamoeba keratitis (AK) and a fatal brain infection known as granulomatous amoebic encephalitis (GAE). Due to the existence of ineffective treatments against Acanthamoeba, it has become a potential threat to all contact lens users and immunocompromised patients. Metal nanoparticles have been proven to have various antimicrobial properties against bacteria, fungi, and parasites. Previously, different types of cobalt nanoparticles showed some promise as anti-acanthamoebic agents. In this study, the objectives were to synthesize and characterize the size, morphology, and crystalline structure of cobalt phosphate nanoparticles, as well as to determine the effects of different sizes of cobalt metal-based nanoparticles against A. castellanii. Cobalt phosphate octahydrate (CHP), Co3(PO4)2•8H2O, was synthesized by ultrasonication using a horn sonicator, then three different sizes of cobalt phosphates Co3(PO4)2 were produced through calcination of Co3(PO4)2•8H2O at 200 °C, 400 °C and 600 °C (CP2, CP4, CP6). These three types of cobalt phosphate nanoparticles were characterized using a field emission scanning electron microscope (FESEM), energy dispersive X-ray spectroscopy (EDX), and X-ray diffraction (XRD) analysis. Next, the synthesized nanoparticles were subjected to biological assays to investigate their amoebicidal, amoebistatic, anti-encystation, and anti-excystation effects against A. castellanii, as well as cell cytotoxicity. The overall results showed that 1.30 ± 0.70 µm of CHP microflakes demonstrated the best anti-acanthemoebic effects at 100 µg/mL, followed by 612.50 ± 165.94 nm large CP6 nanograins. However, amongst the three tested cobalt phosphates, Co3(PO4)2, the smaller nanoparticles had stronger antiamoebic effects against A. castellanii. During cell cytotoxicity analysis, CHP exhibited only 15% cytotoxicity against HeLa cells, whereas CP6 caused 46% (the highest) cell cytotoxicity at the highest concentration, respectively. Moreover, the composition and morphology of nanoparticles is suggested to be important in determining their anti-acathamoebic effects. However, the molecular mechanisms of cobalt phosphate nanoparticles are still unidentified. Nevertheless, the results suggested that cobalt phosphate nanoparticles hold potential for development of nanodrugs against Acanthamoeba.
    Matched MeSH terms: Encephalitis
  14. Liou AT, Liao CC, Chou SF, Chang YS, Chang CS, Shih C
    J Biomed Sci, 2019 Nov 11;26(1):93.
    PMID: 31711481 DOI: 10.1186/s12929-019-0585-y
    BACKGROUND: Enterovirus 71 (EV71 or EV-A71) was first identified in California about half a century ago. In recent years, outbreaks of EV-A71 were prevalent worldwide, including Taiwan, Malaysia, Singapore, Japan, and China. Between 2008 and 2011, China alone reported 1894 deaths associated with EV-A71 infection. In mild cases, EV-A71 can cause herpangina and hand-foot-and-mouth disease (HFMD). However, in severe cases, it could cause neurological disorders, including meningitis and encephalitis. Cardiopulmonary failure is common among hospitalized children with EV-A71 infection. No effective FDA-approved therapeutics against EV-A71 are clinically available.

    METHODS: We report the establishment of an immunocompetent wild type strain 129 (wt-129) mouse model, which can be cross-species infected with human EV-A71 clinical isolates via an intraperitoneal route.

    RESULTS: One intriguing disease phenotype of this new model is the development of characteristic "White-Jade" patches in the muscle, which lost sporadically the normal pink color of uninfected muscle. Viral VP1 protein and massive leukocyte infiltration were detected in muscles with or without white-jades. We demonstrated further that hypoxia is a general phenomenon associated with white-jades in both immunocompetent and immunodeficient mouse models. Therefore, hypoxia appears to be a feature intrinsic to EV-A71 infection, irrespective of its host's immunogenetic background. To date, no effective treatment for EV-A71 is available. Here, using this new wt-129 mouse model, we showed that timely treatment with compound R837 (a TLR7 immune modulator) via oral or intraperitoneal routes, rescued the hypoxia, limb paralysis, and death at a high therapeutic efficacy.

    CONCLUSIONS: In this new immunocompetent mouse 129 model, we observed an unexpected white-jade phenotype and its associated hypoxia. The successful treatment with TLR7 immune modulators via an oral route, provide us a new research direction for EV-A71 basic science and translational research. It remains an open issue whether R837 or its related compounds, will be a promising drug candidate in clinical trials in EV-A71 endemic or epidemic areas in the future.

    Matched MeSH terms: Encephalitis
  15. Mungroo MR, Shahbaz MS, Anwar A, Saad SM, Khan KM, Khan NA, et al.
    ACS Chem Neurosci, 2020 08 19;11(16):2438-2449.
    PMID: 31961126 DOI: 10.1021/acschemneuro.9b00596
    Naegleria fowleri and Balamuthia mandrillaris are protist pathogens that infect the central nervous system, causing primary amoebic meningoencephalitis and granulomatous amoebic encephalitis with mortality rates of over 95%. Quinazolinones and their derivatives possess a wide spectrum of biological properties, but their antiamoebic effects against brain-eating amoebae have never been tested before. In this study, we synthesized a variety of 34 novel arylquinazolinones derivatives (Q1-Q34) by altering both quinazolinone core and aryl substituents. To study the antiamoebic activity of these synthetic arylquinazolinones, amoebicidal and amoebistatic assays were performed against N. fowleri and B. mandrillaris. Moreover, amoebae-mediated host cells cytotopathogenicity and cytotoxicity assays were performed against human keratinocytes cells in vitro. The results revealed that selected arylquinazolinones derivatives decreased the viability of B. mandrillaris and N. fowleri significantly (P < 0.05) and reduced cytopathogenicity of both parasites. Furthermore, these compounds were also found to be least cytotoxic against HaCat cells. Considering that nanoparticle-based materials possess potent in vitro activity against brain-eating amoebae, we conjugated quinazolinones derivatives with silver nanoparticles and showed that activities of the drugs were enhanced successfully after conjugation. The current study suggests that quinazolinones alone as well as conjugated with silver nanoparticles may serve as potent therapeutics against brain-eating amoebae.
    Matched MeSH terms: Infectious Encephalitis
  16. Banerjee S, Gupta N, Kodan P, Mittal A, Ray Y, Nischal N, et al.
    Intractable Rare Dis Res, 2019 Feb;8(1):1-8.
    PMID: 30881850 DOI: 10.5582/irdr.2018.01130
    Nipah virus, an enveloped ribonucleic acid virus, has been a major cause of encephalitis out-breaks with high mortality, primarily in the Indo-Bangladesh regions. Except for the first outbreak in Malaysia-Singapore, which was related to contact with pigs and the outbreak in Philippines associated with horse slaughter, most other outbreaks have affected the Indo- Bangladesh regions. The Indo-Bangladesh outbreaks were associated with consumption of raw date palm sap contaminated by fruit bats and had a very high secondary attack rate. The patient usually presents with fever, encephalitis and/or respiratory involvement with or without thrombocytopenia, leukopenia and transaminitis. Diagnosis can be confirmed by isolation and nucleic acid amplification in the acute phase or antibody detection during the convalescent phase. Treatment is mostly limited to supportive care and syndromic management of acute encephalitis syndrome. Ribavirin, m102.4 monoclonal antibody and favipiravir are the only anti-virals with some activity against Nipah virus. Standard precautions, hand hygiene and personal protective equipments are the cornerstone of comprehensive infection prevention and control strategy. With the recent outbreaks affecting newer geographical areas, there is a need for physicians to be aware of this disease and keep abreast of its current detection and management strategies.
    Matched MeSH terms: Encephalitis
  17. Nissapatorn V, Lee C, Khairul Anuar A
    JUMMEC, 2000;5:89-92.
    A relTospective study was conducted in Hospital Kuala Lumpur, May, 2001.49 (12.1%) of 406 AIDS patients were diagnosed as opportunistic infections related to the central nervous system. The sex ratio (M:F) was 7.2. The median age was 34 years. The predominant age group for male as same as female was 25-34 years.The majority of the study subjects were Chinese (79.6%), married (49%), unemployed (42.9%) and heterosexuals (95.9%) as the risk behavior related to HlV infection. The most frequent clinical manifestations was headache (71.4%). At the time of diagnosis, the greater number of patients 39 (79.6%) had CD4 count < 200 celVcumm. Outcome of acute therapy the patients had a complete (85.7%), treatment continued (10.3%), and transfer to other hospital (2.00/0). Toxoplasmic encephalitis (7.6%) and cryptococcosis (3.9%) were the frequent cause of focal intracerebral lesions and meningitis in these patients respectively. Oral candidiasis (32.7%) was the most common among other opportunistic infections in this study. KEYWORDS: AIDS, Opportunistic infections. central nervous system, clinical manifestations, outcome.
    Matched MeSH terms: Encephalitis
  18. Ain-Najwa MY, Yasmin AR, Omar AR, Arshad SS, Abu J, Mohammed HO, et al.
    One Health, 2020 Dec;10:100134.
    PMID: 32405525 DOI: 10.1016/j.onehlt.2020.100134
    West Nile virus (WNV) is a zoonotic mosquito-borne flavivirus that is harbored and amplified by wild birds via the enzootic transmission cycle. Wide range of hosts are found to be susceptible to WNV infection including mammals, amphibians and reptiles across the world. Several studies have demonstrated that WNV was present in the Malaysian Orang Asli and captive birds. However, no data are available on the WNV prevalence in wild birds found in Malaysia. Therefore this study was conducted to determine the serological and molecular prevalence of WNV in wild birds in selected areas in the West Coast of Peninsular Malaysia. Two types of wild birds were screened, namely migratory and resident birds in order to explore any possibility of WNV transmission from the migratory birds to the resident birds. Thus, a cross-sectional study was conducted at the migratory birds sanctuary located in Kuala Gula, Perak and Kapar, Selangor by catching 163 migratory birds, and 97 resident birds from Kuala Gula and Parit Buntar, Perak at different time between 2016 and 2017 (Total, n = 260). Blood and oropharyngeal swabs were collected for serological and molecular analysis, respectively. Serum were screened for WNV antibodies using a commercial competitive ELISA (c-ELISA) (ID Screen® West Nile Competition Multi-species ELISA, ID VET, Montpellier, France) and cross-reactivity towards Japanese Encephalitis virus (JEV) was also carried out using the JEV-double antigen sandwich (DAS) ELISA. Oropharyngeal swabs were subjected to one-step RT-PCR to detect WNV RNA, in which positive reactions were subsequently sequenced. WNV seropositive rate of 18.71% (29/155) at 95% CI (0.131 to 0.260) and molecular prevalence of 15.2% (16/105) at 95% CI (0.092 to 0.239) were demonstrated in migratory and resident wild birds found in West Coast Malaysia. Phylogenetic analyses of the 16 WNV isolates found in this study revealed that the local strains have 99% similarity to the strains from South Africa and were clustered under lineage 2. Evidence of WNV infection in resident and migratory birds were demonstrated in this study. As a summary, intervention between migratory birds, resident birds and mosquitoes might cause the introduction and maintenance of WNV in Malaysia, however the assumption could be further proven by studying the infection dynamics in the mosquitoes present in the studied areas.
    Matched MeSH terms: Encephalitis Virus, Japanese
  19. Phan TG, Mori D, Deng X, Rajindrajith S, Ranawaka U, Fan Ng TF, et al.
    Virology, 2015 Aug;482:98-104.
    PMID: 25839169 DOI: 10.1016/j.virol.2015.03.011
    Viruses with small circular ssDNA genomes encoding a replication initiator protein can infect a wide range of eukaryotic organisms ranging from mammals to fungi. The genomes of two such viruses, a cyclovirus (CyCV-SL) and gemycircularvirus (GemyCV-SL) were detected by deep sequencing of the cerebrospinal fluids of Sri Lankan patients with unexplained encephalitis. One and three out of 201 CSF samples (1.5%) from unexplained encephalitis patients tested by PCR were CyCV-SL and GemyCV-SL DNA positive respectively. Nucleotide similarity searches of pre-existing metagenomics datasets revealed closely related genomes in feces from unexplained cases of diarrhea from Nicaragua and Brazil and in untreated sewage from Nepal. Whether the tropism of the cyclovirus and gemycircularvirus reported here include humans or other cellular sources in or on the human body remains to be determined.
    Matched MeSH terms: Encephalitis/virology*
  20. Paudel YN, Othman I, Shaikh MF
    Front Pharmacol, 2020;11:613009.
    PMID: 33732146 DOI: 10.3389/fphar.2020.613009
    Epilepsy is a chronic brain disease afflicting around 70 million global population and is characterized by persisting predisposition to generate epileptic seizures. The precise understanding of the etiopathology of seizure generation is still elusive, however, brain inflammation is considered as a major contributor to epileptogenesis. HMGB1 protein being an initiator and crucial contributor of inflammation is known to contribute significantly to seizure generation via activating its principal receptors namely RAGE and TLR4 reflecting a potential therapeutic target. Herein, we evaluated an anti-seizure and memory ameliorating potential of an anti-HMGB1 monoclonal antibody (mAb) (1, 2.5 and 5 mg/kg, I.P.) in a second hit Pentylenetetrazol (PTZ) (80 mg/kg, I.P.) induced seizure model earlier stimulated with Pilocarpine (400 mg/kg, I.P.) in adult zebrafish. Pre-treatment with anti-HMGB1 mAb dose-dependently lowered the second hit PTZ-induced seizure but does not alter the disease progression. Moreover, anti-HMGB1 mAb also attenuated the second hit Pentylenetetrazol induced memory impairment in adult zebrafish as evidenced by an increased inflection ration at 3 and 24 h trail in T-maze test. Besides, decreased level of GABA and an upregulated Glutamate level was observed in the second hit PTZ induced group, which was modulated by pre-treatment with anti-HMGB1 mAb. Inflammatory responses occurred during the progression of seizures as evidenced by upregulated mRNA expression of HMGB1, TLR4, NF-κB, and TNF-α, in a second hit PTZ group, which was in-turn downregulated upon pre-treatment with anti-HMGB1 mAb reflecting its anti-inflammatory potential. Anti-HMGB1 mAb modulates second hit PTZ induced changes in mRNA expression of CREB-1 and NPY. Our findings indicates anti-HMGB1 mAb attenuates second hit PTZ-induced seizures, ameliorates related memory impairment, and downregulates the seizure induced upregulation of inflammatory markers to possibly protect the zebrafish from the incidence of further seizures through via modulation of neuroinflammatory pathway.
    Matched MeSH terms: Encephalitis
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