16 research outputs found

    Design and validation of small interfering RNA on respiratory syncytial virus M2-2 gene: a potential approach in RNA interference on viral replication

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    Human respiratory syncytial virus (RSV) is the leading cause of severe lower respiratory tract infection in infants and young children globally and is a significant pathogen of the elderly and immunocompromised. The M2-2 protein of respiratory syncytial virus (RSV) is particularly important in regulation of viral RNA transcription and replication that could be a potential anti-viral candidate against RSV infection. In this study, we designed and validated siRNAs that specifically target the RSV M2-2 gene. Four siRNAs targeting different regions of the M2-2 gene were designed using web tool. In-vitro evaluation of silencing effect was performed by using RSV infected Vero cell line. Viral M2-2 linked GFP recombinant plasmid was co-transfected with non-targeted siRNA, Pooled siRNA, siRNA 1, siRNA 2, siRNA 3 and siRNA 4 using synthetic cationic polymer. The silencing effect of M2-2 gene at the protein level was measured both qualitatively and quantitatively by using fluorescence microscopy and flow cytometry. Meanwhile, the silencing effect at the mRNA level was assessed by using RT-qPCR. This study showed that all four designed siRNAs can effectively and efficiently silence M2-2 gene. siRNA 2 showed the highest (98%) silencing effect on protein level and siRNA 4 with 83.1% at the mRNA level. The viral assay showed no significant cytopathic effects observed after 6 days post-infection with siRNAs. In conclusion, this study showed the effectiveness of siRNA in silencing M2-2 gene both at the protein and mRNA level which could potentially be used as a novel therapeutic agent in the treatment of RSV infection. However, further study is warranted to investigate the silencing effect of M2-2 protein and inhibition of RSV infection

    Naturally occurring hepatitis B virus surface antigen mutant variants in Malaysian blood donors and vaccinees

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    Hepatitis B virus surface mutants are of enormous importance because they are capable of escaping detection by serology and can infect both vaccinated and unvaccinated populations, thus putting the whole population at risk. This study aimed to detect and characterise hepatitis B-escaped mutants among blood donors and vaccinees. One thousand serum samples were collected for this study from blood donors and vaccinees. Hepatitis B surface antigen, antibodies and core antibodies were tested using a commercial enzyme-linked immunosorbent assay (ELISA) kit. DNA detection was performed via nested polymerase chain reaction (PCR), and the S gene was sequenced and analysed using bioinformatics. Of the 1,000 samples that were screened, 5.5 % (55/1,000) were found to be HBsAg-negative and anti-HBc- and HBV DNA-positive. All 55 isolates were found to belong to genotype B. Several mutations were found across all the sequences from synonymous and non-synonymous mutations, with the most nucleotide mutations occurring at position 342, where adenine was replaced by guanine, and cytosine at position 46 was replaced by adenine in 96.4 % and 98 % of the isolates, respectively. Mutation at position 16 of the amino acid sequence was found to be common to all the Malaysian isolates, with 85.7 % of the mutations occurring outside the major hydrophilic region. This study revealed a prevalence of 5.5 % for hepatitis B-escaped mutations among blood donors and vaccinated undergraduates, with the most common mutation being found at position 16, where glutamine was substituted with lysine

    Molecular and serological detection of occult hepatitis B virus among healthy hepatitis B surface antigen-negative blood donors in Malaysia.

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    Background: Occult hepatitis B infections are becoming a major global threat, but the available data on its prevalence in various parts of the world are often divergent. Objective: This study aimed to detect occult hepatitis B virus in hepatitis B surface antigen-negative serum using anti-HBc as a marker of previous infection. Patient and Methods: A total of 1000 randomly selected hepatitis B surface antigen-negative sera from blood donors were tested for hepatitis B core antibody and hepatitis B surface antibody using an ELISA and nested polymerase chain reaction was done using primers specific to the surface gene (S-gene). Results: Of the 1000 samples 55 (5.5%) were found to be reactive, of which 87.3% (48/55) were positive for hepatitis B surface antibody, indicating immunity as a result of previous infection however, that does not exclude active infection with escaped mutant HBV. Nested PCR results showed the presence of hepatitis B viral DNA in all the 55 samples that were positive for core protein, which is in agreement with the hepatitis B surface antibody result. Conclusion: This study reveals the 5.5% prevalence of occult hepatitis B among Malaysian blood donors as well as the reliability of using hepatitis B core antibody in screening for occult hepatitis B infection in low endemic, low socioeconomic settings

    VP37 Protein Inhibitors for Mpox Treatment: Highlights on Recent Advances, Patent Literature, and Future Directions

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    Monkeypox disease (Mpox) has threatened humankind worldwide since mid-2022. The Mpox virus (MpoxV) is an example of Orthopoxviruses (OPVs), which share similar genomic structures. A few treatments and vaccines are available for Mpox. OPV-specific VP37 protein (VP37P) is a target for developing drugs against Mpox and other OPV-induced infections such as smallpox. This review spotlights the existing and prospective VP37P inhibitors (VP37PIs) for Mpox. The non-patent literature was collected from PubMed, and the patent literature was gathered from free patent databases. Very little work has been carried out on developing VP37PIs. One VP37PI (tecovirimat) has already been approved in Europe to treat Mpox, while another drug, NIOCH-14, is under clinical trial. Developing tecovirimat/NIOCH-14-based combination therapies with clinically used drugs demonstrating activity against Mpox or other OPV infections (mitoxantrone, ofloxacin, enrofloxacin, novobiocin, cidofovir, brincidofovir, idoxuridine, trifluridine, vidarabine, fialuridine, adefovir, imatinib, and rifampicin), immunity boosters (vitamin C, zinc, thymoquinone, quercetin, ginseng, etc.), and vaccines may appear a promising strategy to fight against Mpox and other OPV infections. Drug repurposing is also a good approach for identifying clinically useful VP37PIs. The dearth in the discovery process of VP37PIs makes it an interesting area for further research. The development of the tecovirimat/NIOCH-14-based hybrid molecules with certain chemotherapeutic agents looks fruitful and can be explored to obtain new VP37PI. It would be interesting and challenging to develop an ideal VP37PI concerning its specificity, safety, and efficacy

    Hepatitis E virus infection in the perspective of acute-on-chronic liver failure

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    Introduction: Hepatitis E virus is a non-enveloped virus measuring 27 to 34nm, which belongs to the hepeviridae family. Its transmission is predominantly fecal oral and it is a common cause of acute viral hepatitis worldwide. Hepatitis E virus may cause serious disease, leading to high mortality in chronic liver disease patients, leading to the development of acute-on-chronic liver failure. Objective: This review aimed at summarizing the role played by HEV on the exacerbation of chronic hepatitis B and the pathophysiology of acute-on-chronic liver failure. Evidence acquisition: Peer-reviewed journal articles search were conducted using the university Putra Malaysia online subscribed databases in the area of Health Sciences and Medicine via Medline, SCOPUS and Google Scholar search engine. This review aims to summarize the impact of hepatitis E virus in acute-on-chronic liver failure pathogenesis. Development: Acute-onchronic liver failure has been considered an acute deterioration of liver function and clinical status in chronic hepatitis or cirrhotic patients. The transition from chronic hepatitis to cirrhotic as well as acute-on-chronic liver failure is mainly via pro-inflammatory cytokines; the clinical picture is similar to that of septic shock and multi-organ failure. Conclusion: Hepatitis E virusinfected patients may worsen and deteriorate to acute-on chronic infection, which constitutes two concurrent insults: acute and chronic with qualitatively different degrees of insult, leading to increased mortality as a result of organ failure with subsequent progression to multi-organ failure and being a leading cause of cirrhotic decompensation

    Optical clearing methods: An overview of the techniques used for the imaging of 3D spheroids

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    Spheroids have emerged as in vitro models that reproduce in a great extent the architectural microenvironment found in human tissues. However, the imaging of 3D cell cultures is highly challenging due to its high thickness, which results in a light-scattering phenomenon that limits light penetration. Therefore, several optical clearing methods, widely used in the imaging of animal tissues, have been recently explored to render spheroids with enhanced transparency. These methods are aimed to homogenize the microtissue refractive index (RI) and can be grouped into four different categories, namely (a) simple immersion in an aqueous solution with high RI; (b) delipidation and dehydration followed by RI matching; (c) delipidation and hyperhydration followed by RI matching; and (d) hydrogel embedding followed by delipidation and RI matching. In this review, the main optical clearing methods, their mechanism of action, advantages, and disadvantages are described. Furthermore, the practical examples of the optical clearing methods application for the imaging of 3D spheroids are highlighted.info:eu-repo/semantics/publishedVersio

    The Effect of Cinnamon Extract on Spermatogenesis and

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    . (2011). Haematological and serum biochemical indices of growing rabbits fed camel blood rumen content mixture

    Quantitative hepatitis B e antigen: a better predictor of hepatitis B virus DNA than quantitative hepatitis B surface antigen

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    Background: Hepatitis B surface antigen is usually secreted by infected hepatocytes in the form of subviral particles rather than infectious virions, while the hepatitis B e antigen originates from the core gene and is modified and secreted by hepatocytes into the circulation and functions as a marker of active viral replication. This study aimed to study the relationship between HBV DNA and quantitative hepatitis B surface and e antigen in Malaysian patients. Methods: A total of 82 chronic hepatitis B patients were recruited for this study from the Hepatology Department of Selayang Hospital. Quantitative hepatitis surface and e antigen was performed retrospectively on frozen plasma using enzyme linked immunosorbent assay according to the manufacturer's instructions. Hepatitis B viral DNA was extracted from all plasma samples and quantified using real-time PCR. Results: Quantitative hepatitis B surface and e antigens were found be high in 54.9% and 52.4% of the patients, respectively, while hepatitis B virus DNA level was high in 70.7%. The median of the viral load of HBV was 8,934.89 IU/mL and both hepatitis B surface and e antigens were also found to be high on average for qHBsAg (M = 5.19 IU/mL, SD ± 4. 33) and qHBeAg (M = 4.74IU/mL, SD ± 4.20), with qHBeAg being more strongly correlated to HBV DNA than qHBsAg (r = 0.893; p < 0.01). Conclusions: This study revealed HBeAg to be the most appropriate marker that correlates well with HBV DNA, thus not completely novel but confirmative, and related to the Malaysian situation
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