417 research outputs found

    Encephalitic Development in Alphaviral Infection

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    Alfavirusna kimerična cjepiva protiv alfavirusnih uzročnika encefalitisa

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    Encephalitic viruses in the Family Togaviridae, genus Alphavirus are zoonotic pathogens that are transmitted via hematophagous arthropods and have a widespread distribution in North, Central and South America and include Venezuelan equine encephalitis virus (VEEV), Western equine encephalitis virus (WEEV), Eastern equine encephalitis virus (EEEV). The deficit in specific antiviral drugs or vaccines for effective treatment or prevention of infection and disease in humans has prompted the development of recombinant live attenuated vaccines utilizing Sindbis virus (SIN), a relatively nonpathogenic alphavirus in humans, as a means for expression all of the structural proteins of the virulent alphaviruses. The safety and efficacy of these chimeric SIN/VEE viruses have been extensively evaluated in animal models, including immunodeficient mice. The epidemiological distribution of these viruses and the disease manifestations are reviewed briefly. Progress in the evaluation of the safety, immunogenicity and efficacy of the SIN/VEEV and SIN/EEEV candidate vaccines against VEEV and EEEV, respectively, as well as chimeric SIN/RVFV vaccine candidates and the potential for elucidation of the mechanism of efficacy employing mice with selective immunodeficiencies is discussed.Virusi encefalitisa iz porodice Togaviridae, roda Alphavirus su zoonozni uzročnicikoje prenose hematofagni člankonošci rasprostranjeni u Sjevernoj, Centralnoj i Južnoj Americi te uključuju virus venezuelskog konjskog encefalitisa (engl. Venezuelan equine encephalitis virus, VEEV), virus zapadnog konjskog encefalitisa (engl. Western equine encephalitis virus, WEEV) i virus istočnog konjskog encefalitisa (engl. Eastern equine encephalitis virus, EEEV). Manjak specifičnih antivirusnih lijekova ili cjepiva za učinkovito liječenje ili sprječavanje infekcija i bolesti u ljudi potaklo je razvoj rekombiniranih živih atenuiranih cjepiva koja sadrže Sindbis virus (SIN), relativno bezopasan alfavirus za ljude, kao ekspresijski vektor svih strukturalnih proteina virulentnih alfavirusa. Sigurnost i učinkovitost ovih kimeričnih SIN/VEE virusa opsežno je proučavana na životinjskim modelima, uključujući imunodeficijentne miševe. Epidemiološka rasprostranjenost ovih virusa i manifestacije bolesti ukratko su opisane. Raspravlja se o postignutom napretku u ocjenjivanju sigurnosti, imunogeničnosti i učinkovitosti SIN/VEEV i SIN/EEEV potencijalnih cjepiva protiv VEEV odnosno EEEV, kao i potencijalnih kimeričnih SIN/RVFV cjepiva te moguće razjašnjenje mehanizma djelotvornosti koristeći miševe selektivne imunodeficijentnosti

    Lassa virus isolates from Mali and the Ivory Coast represent an emerging fifth lineage.

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    Previous imported cases of Lassa fever (LF) into the United Kingdom from the Ivory Coast and Mali, as well as the detection of Lassa virus (LASV) among the Mastomys natalensis population within Mali has led to the suggestion that the endemic area for LF is expanding. Initial phylogenetic analyses arrange isolates from Mali and the Ivory Coast separately from the classical lineage IV isolates taken from Sierra Leone, Guinea, and Liberia. The availability of full genome sequences continues to increase, allowing for a more complete phylogenetic comparison of the isolates from Mali and the Ivory Coast to the other existing isolates. In this study, we utilized a Bayesian approach to infer the demographic histories of each LASV isolate for which the full sequence was available. Our results indicate that the isolates from Mali and the Ivory Coast group separately from the isolates of lineage IV, comprising a distinct fifth lineage. The split between lineages IV and V is estimated to have occurred around 200-300 years ago, which coincides with the colonial period of West Africa

    Use of the informational spectrum methodology for rapid biological analysis of the novel coronavirus 2019-nCoV: prediction of potential receptor, natural reservoir, tropism and therapeutic/vaccine target [version 1; peer review: awaiting peer review]

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    A novel coronavirus recently identified in Wuhan, China (2019-nCoV) has expanded the number of highly pathogenic coronaviruses affecting humans. The 2019-nCoV represents a potential epidemic or pandemic threat, which requires a quick response for preparedness against this infection. The present report uses the informational spectrum methodology to identify the possible origin and natural host of the new virus, as well as putative therapeutic and vaccine targets. The performed in silico analysis indicates that the newly emerging 2019-nCoV is closely related to severe acute respiratory syndrome (SARS)-CoV and, to a lesser degree, Middle East respiratory syndrome (MERS)-CoV. Moreover, the well-known SARS-CoV receptor (ACE2) might be a putative receptor for the novel virus as well. Additional results indicated that civets and poultry are potential candidates for the natural reservoir of the 2019-nCoV, and that domain 288-330 of S1 protein from the 2019-nCoV represents promising therapeutic and/or vaccine target.info:eu-repo/semantics/publishedVersio

    Simple Theoretical Criterion for Selection of Natural Compounds with Anti-COVID-19 Activity

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    A novel human coronavirus, severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), has become the leading threat to global health. An effective antiviral could not only help those still vulnerable to the virus but could be a critical treatment if a virus emerges toward evading coronavirus disease 2019 (COVID-19) vaccines. Despite the significant efforts to test already-approved drugs for their potential to kill the virus, researchers found very few actually worked. Methods: The present report uses the electronic molecular descriptors, the quasi-valence number (AQVN), and the electron-ion interaction potential (EIIP), for the analysis of natural compounds with proven therapeutic activity against the COVID-19. Results: Based on the analysis of the electronic properties of natural compounds which are effective against SARS-CoV-2 virus the simple theoretical criterion for the selection of candidate compounds for the treatment of COVID-19 is proposed. Conclusions: The proposed theoretical criterion can be used for the identification and optimization of new lead compounds for the treatment of the COVID-19 disease and for the selection of the food and food supplements which could have a beneficial effect on COVID-19 patients

    Review of Mammarenavirus Biology and Replication

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    The family Arenaviridae is divided into three genera: Mammarenavirus, Reptarenavirus, and Hartmanivirus. The Mammarenaviruses contain viruses responsible for causing human hemorrhagic fever diseases including New World viruses Junin, Machupo, Guanarito, Sabia, and Chapare virus and Old World viruses Lassa, and Lujo virus. These two groups of arenaviruses share the same genome organization composed of two ambisense RNA segments. These segments contain four open reading frames that encode for four proteins: the nucleoprotein, glycoprotein precursor, L protein, and Z. Despite their genome similarities, these groups exhibit marked differences in their replication life cycles. This includes differences in attachment, entry, and immune evasion. By understanding the intricacy of replication in each of these viral species we can work to develop counter measures against human diseases. This includes the development of vaccines and antivirals for these emerging viral threats. Currently only the vaccine against Junin virus, Candid#1, is in use as well as Ribavirin for treatment of Lassa Fever. In addition, small molecule inhibitors can be developed to target various aspects of the virus life cycle. In these ways an understanding of the arenavirus replication cycle can be used to alleviate the mortality and morbidity of these infections worldwide

    MAVS Is essential for primary CD4 + T cell immunity but not for recall T cell responses following an attenuated West Nile virus infection

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    ABSTRACT The use of pathogen recognition receptor (PRR) agonists and the molecular mechanisms involved have been the major focus of research in individual vaccine development. West Nile virus (WNV) nonstructural (NS) 4B-P38G mutant has several features for an ideal vaccine candidate, including significantly reduced neuroinvasiveness, induction of strong adaptive immunity, and protection of mice from wild-type (WT) WNV infection. Here, we determined the role of mitochondrial antiviral signaling protein (MAVS), the adaptor protein for RIG-I-like receptor in regulating host immunity against the NS4B-P38G vaccine. We found that Mavs −/− mice were more susceptible to NS4B-P38G priming than WT mice. Mavs −/− mice had a transiently reduced production of antiviral cytokines and an impaired CD4 + T cell response in peripheral organs. However, antibody and CD8 + T cell responses were minimally affected. NS4B-P38G induced lower type I interferon (IFN), IFN-stimulating gene, and proinflammatory cytokine responses in Mavs −/− dendritic cells and subsequently compromised the antigen-presenting capacity for CD4 + T cells. Interestingly, Mavs −/− mice surviving NS4B-P38G priming were all protected from a lethal WT WNV challenge. NS4B-P38G-primed Mavs −/− mice exhibited equivalent levels of protective CD4 + T cell recall response, a modestly reduced WNV-specific IgM production, but more robust CD8 + T cell recall response. Taken together, our results suggest that MAVS is essential for boosting optimal primary CD4 + T cell responses upon NS4B-P38G vaccination and yet is dispensable for host protection and recall T cell responses during secondary WT WNV infection. IMPORTANCE The production of innate cytokines induced by the recognition of pathogen recognition receptors (PRRs) via their cognate ligands are critical for enhancing antigen-presenting cell functions and influencing T cell responses during microbial infection. The use of PRR agonists and the underlying molecular mechanisms have been the major focus in individual vaccine development. Here, we determined the role of mitochondrial antiviral-signaling protein (MAVS), the adaptor protein for RIG-I like receptor in regulating host immunity against the live attenuated West Nile virus (WNV) vaccine strain, the nonstructural (NS) 4B-P38G mutant. We found that MAVS is important for boosting optimal primary CD4 + T cell response during NS4B-P38G vaccination. However, MAVS is dispensable for memory T cell development and host protection during secondary wild-type WNV infection. Overall, these results may be utilized as a paradigm to aid in the rational development of other efficacious live attenuated flavivirus vaccines

    Drug Repurposing for Candidate SARS-CoV-2 Main Protease Inhibitors by a Novel in Silico Method

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    The SARS-CoV-2 outbreak caused an unprecedented global public health threat, having a high transmission rate with currently no drugs or vaccines approved. An alternative powerful additional approach to counteract COVID-19 is in silico drug repurposing. The SARS-CoV-2 main protease is essential for viral replication and an attractive drug target. In this study, we used the virtual screening protocol with both long-range and short-range interactions to select candidate SARS-CoV-2 main protease inhibitors. First, the Informational spectrum method applied for small molecules was used for searching the Drugbank database and further followed by molecular docking. After in silico screening of drug space, we identified 57 drugs as potential SARS-CoV-2 main protease inhibitors that we propose for further experimental testing. © 2020 by the authors

    Novel neurodigital interface reduces motion sickness in virtual reality

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    Virtual reality (VR) is a computer-created 3D environment with a focus on realistic scenes and pictures created for entertainment, medical and/or educational and training purposes. One of the major side effects of VR immersion reported in the scientific literature, media and social media is Visually Induced Motion Sickness (VIMS), with clinical symptoms such as disorientation, nausea, and oculomotor discomfort. VIMS is mostly caused by the discrepancy between the visual and vestibular systems and can lead to dizziness, nausea, and disorientation. In this study, we present one potential novel solution to combat motion sickness in VR, showcasing a significant reduction of nausea in VR users employing the META Quest 2 headsets in conjunction with a whole-body controller. Using a neurodigital approach, we facilitate a more immersive and comfortable VR experience. Our findings indicate a marked reduction in VR-induced nausea, paving the way to promote VR technology for broader applications across various fields
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