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Effects of bafilomycin A1 on Japanese encephalitis virus in C6/36 mosquito cells.

Involvement of intracellular acidic compartments in the early phase of Japanese encephalitis (JE) virus infection of C6/36 mosquito cells was examined by bafilomycin A1, a specific inhibitor of vacuolar type H(+)-ATPase (V-ATPase). Dose dependent reduction of viral envelope protein (E) produced into the infected culture fluid was observed by pretreating the cells with 0.25 to 1.0 microM bafilomycin A1. In synchronized infection, cell surface-bound virions were internalized immediately by heating at 31 degrees C, followed by the release of nucleocapsid into the cytosol within a short lag period…

Differential immune recognition of LCMV nucleoprotein and glycoprotein in transgenic mice expressing LCMV cDNA genes.

We have generated doubly transgenic (DT) mice that independently express cDNA genes for the nucleocapsid protein (NP) and the surface glycoproteins (GP) of lymphocytic choriomeningitis virus (LCMV). By RT-PCR, transcription of both transgenes was detected at low levels in brain and kidney but was not observed in the thymus. Additionally, transcription of the GP transgene was observed in the spleen. Following challenge with exogenous LCMV, an anti-NP CTL response was induced in LCMV-infected DT mice, suggesting that nonresponsiveness to NP had not been established. In contrast, LCMV- infected D…

Determination and comparative analysis of the small RNA genomic sequences of California encephalitis, Jamestown Canyon, Jerry Slough, Melao, Keystone and Trivittatus viruses (Bunyaviridae, genus Bunyavirus, California serogroup).

The nucleotide sequences of the small (S) genomic RNAs of six California (CAL) serogroup bunyaviruses (Bunyaviridae: genus Bunyavirus) were determined. The S RNAs of two California encephalitis virus strains, two Jamestown Canyon virus strains, Jerry Slough virus, Melao virus, Keystone virus and Trivittatus virus contained the overlapping nucleocapsid (N) and non-structural (NSs) protein open reading frames (ORFs) as described previously for the S RNAs of other CAL serogroup viruses. All N protein ORFs were 708 nucleotides in length and encoded a putative 235 amino acid gene product. The NSs O…

Mumps virus infects beta cells in human fetal islet cell cultures upregulating the expression of HLA class I molecules.

The ability of mumps virus to infect pancreatic Beta cells and cause alterations in their HLA expression was evaluated in cultured human fetal islet cell clusters. Mumps virus could be isolated during the whole culture period (6-8 days) and 60% of cells, including Beta cells, contained viral nucleocapsid protein at the end of the culturing. A minor decrease in insulin secretion was observed in some of the infected cultures. The infection was invariably associated with an increase in the expression of HLA class I molecules. This enhancement was mediated by soluble factors secreted by infected c…

Antigenic relationship between hantaviruses analysed by immunoprecipitation.

Antigenic relationships between seven hantaviruses isolated in Sweden, Belgium, Korea, European U.S.S.R. and Asian U.S.S.R. were studied by … the respective HFRS patients. The major cross-reactive antigen between the antigenic groups was the nucleocapsid protein. Of the two viral glycoproteins, the G2 exhibited weak cross-reactivity between the groups, while the G1 protein appeared to be the least cross-reactive. Patient sera collected at different intervals after the onset of disease showed a marke …

Кинетическое исследование тромбоцитов и фибриногенов у обезьян, инфицированных вирусом Ласса, и ранние патологические события у обезьян, инфицированных вирусом Мопеи.

Для изучения гематологовых и геморрагических аспектов лихорадки Ласса использовалась ресусная обезьяна, ставшая установившейся моделью лихорадки Ласса, а также для изучения вопроса о том, вызывает ли вирус Мопеи (также известный как Мозамбик) какие-либо повреждения клеточной клетки в этой модели. Через шесть дней после подкожного инъекции 10(3.48) формирующих элементов (PFU) вируса Ласса (диссийский штамм) одна группа обезьян получила внутривенную инъекцию 111 аллогенетических тромбоцитов, а другая группа получила 125-I алогеиновый фибриноген. У обезьян, инфицированных вирусом Ласса, возникла

Совпадение в аннотации оригинала
The rhesus monkey, an established model of Lassa fever, was used to study hematologic and hemostatic aspects of Lassa fever and whether Mope … ness with high viremia and typical pathology. Lassa antigen was found in most tissues using a Lassa nucleocapsid-specific monoclonal antibody. Platelet counts remained within normal limits. Platelet and fibrinogen kinetics were similar in infected and control animals. Hematologic and hemostatic changes indicate that disseminated intravascular coagulation plays …

Ultrastructural localization of viral antigens in the CNS of mice persistently infected with lymphocytic choriomeningitis virus (LCMV).

Lymphocytic choriomeningitis virus (LCMV) produces a persistent infection of the nervous system in susceptible mice. To map the localization … nique using monoclonal antibodies showed that persistently infected neurons primarily expressed the nucleocapsid protein antigens of LCMV. Glycopeptide antigens were minimally expressed. Electron-microscopic examination of selected individual infected neurons showed viral antigens exclusively associated with ribosomes. No staining was seen on cell surfaces. Gl …

Virion polypeptide heterogeneity among virulent and avirulent strains of eastern equine encephalitis (EEE) virus.

Comparative analysis of structural virion polypeptides of 24 selected EEE virus strains, representing North and South American types, was performed by one-dimensional discontinuous sodium dodecyl sulfate (SDS)-polyacrylamide-gel electrophoresis (PAGE). The structural proteins of different EEE virus isolates, resolved by this method, exhibited mol.wts. values in the range of 57-60 X 10(3) for (E-1), 51-54 X 10(3) for (E-2) and 35-38 X 10(3) daltons for the core (NP) nucleocapsid. The exception was the South American human lethal virus, TRVL-89287 strain, which was shown to possess only a single…

[SARS-CoV-2-induced non-bacterial endomyocarditis with the development of acquired heart defects].

Patients with damage of the mitral, aortic and tricuspid valves and systolic myocardial dysfunction associated with previous SARS-CoV-2 infection are described. The diagnosis of acquired defect was established in 4 patients based on medical history, electrocardiography, echocardiography, magnetic resonance imaging of the heart, endomyocardial or intraoperative myocardial biopsy, and in one case, autopsy. The study of the myocardium included H&E, Van Gieson staining, immunohistochemical (IHC) study with antibodies to CD3, CD20, CD45, CD68, to the nucleocapsid and Spike proteins of SARS-CoV-2. P…

Enhancement of the physicochemical properties of [Pt(dien)(nucleobase)]2+ for HIVNCp7 targeting.

Physicochemical properties of coordination compounds can be exploited for molecular recognition of biomolecules. The inherent π-π stacking properties of [Pt(chelate)(N-donor)]2+ ([PtN4]) complexes were modulated by systematic variation of the chelate (diethylenetriamine and substituted derivatives) and N-donor (nucleobase or nucleoside) in the formally substitution-inert PtN4 coordination sphere. Approaches to target the HIV nucleocapsid protein HIVNCp7 are summarized building on (i) assessment of stacking interactions with simple tryptophan or tryptophan derivatives to (ii) the tryptophan-con…

Negri bodies are viral factories with properties of liquid organelles.

Replication of Mononegavirales occurs in viral factories which form inclusions in the host-cell cytoplasm. For rabies virus, those inclusions are called Negri bodies (NBs). We report that NBs have characteristics similar to those of liquid organelles: they are spherical, they fuse to form larger structures, and they disappear upon hypotonic shock. Their liquid phase is confirmed by FRAP experiments. Live-cell imaging indicates that viral nucleocapsids are ejected from NBs and transported along microtubules to form either new virions or secondary viral factories. Coexpression of rabies virus N …

Deciphering the biology of porcine epidemic diarrhea virus in the era of reverse genetics.

Emergence of the porcine epidemic diarrhea virus (PEDV) as a global threat to the swine industry underlies the urgent need for deeper unders … viral tropism, entry and virulence, ORF3 and its association with cell culture adaptation, and the nucleocapsid protein and its potential role in modulating PEDV pathogenicity. Finally, we conclude with an exploration of how reverse genetics can help mitigate the global impact of PEDV by addressing the challenges of vaccine development.

[New Method for Stable Expression of SFTS Virus-like Particles in CHO-K1 Cells].

To explore a new method for stable expression of virus-like particles (VLPs) of the severe fever with thrombocytopenia syndrome (SFTS) virus, an expression plasmid for the membrane glycoprotein (GP) and nucleocapsid protein (NP) of the SFTS virus was constructed by fusion of the two proteins via a serine residue, and a yellow fluorescence protein (YFP) gene was introduced into the plasmid as a reporter. CHO-K1 cells were transfected with this plasmid, and stable cell lines constructed using the limited dilution method. Cellular colonies were hand-picked based on YFP with the help of fluorescen…

[Value of CODEHOP RT-pCR in detection of Flavivirus].

This study aims to analyse the value of CODEHOP RT-PCR in the detection of Flavivirus. According to the amino acid sequences of polyproteins of different flaviviruses published in GenBank, a pair of primers was designed using the CODEHOP method. One-step RT-PCR was used to detect Japanese encephalitis virus strain JEV1201, Dengue virus strain JKD001, and yellow fever virus vaccine YV6161. BLAST analysis and phylogenetic analysis were performed after the RT-PCR products of nucleocapsid genes were sequenced. The results showed that this method could amplify Flavivirus specifically, and the size …

Cryo-electron tomography of rubella virus.

Rubella virus is the only member of the Rubivirus genus within the Togaviridae family and is the causative agent of the childhood disease known as rubella or German measles. Here, we report the use of cryo-electron tomography to examine the three-dimensional structure of rubella virions and compare their structure to that of Ross River virus, a togavirus belonging the genus Alphavirus. The ectodomains of the rubella virus glycoproteins, E1 and E2, are shown to be organized into extended rows of density, separated by 9 nm on the viral surface. We also show that the rubella virus nucleocapsid st…

Antibodies against mumps virus component proteins.

The neutralization (NT) test is regarded as the most reliable method for detection of protective antibodies, but is labor-intensive and time consuming. Enzyme-linked immunosorbent assay (EIA) is frequently used in sero-epidemiological studies because of its simplicity and ease of use. In this study, immunofluorescent (IF) antibodies against nucleocapsid (N), fusion (F), and hemagglutinin-neuraminidase (HN) proteins were investigated in comparison with NT and EIA antibodies. The antibody against N protein was dominant in serum samples obtained from patients with a previous history of mumps infe…

Identification of a hydrophobic domain of HA2 essential to morphogenesis of Helicoverpa armigera nucleopolyhedrovirus.

The HA2 protein of the Helicoverpa armigera single-nucleocapsid nucleopolyhedrovirus (HearNPV) is a WASP homology protein capable of nucleating branched actin filaments in the presence of the Arp2/3 complex in vitro. To determine the role of ha2 in the HearNPV life cycle, ha2 knockout and ha2 repair bacmids were constructed. Transfection and infection analysis demonstrated that the ha2 null bacmid was unable to produce infectious budded virus (BV), while the repair bacmid rescued the defect. In vitro analysis demonstrated that the WCA domain of HA2 accelerates Arp2/3-mediated actin assembly an…

Mycophenolic acid inhibits dengue virus infection by preventing replication of viral RNA.

Dengue fever is a mosquito-borne viral disease of global importance with no available antiviral therapy. We assessed the ability of mycophen … lifecycle at which MPA abrogates infection. Early steps in viral infection, such as viral entry and nucleocapsid uncoating, were not the primary targets of MPA action since its inhibitory effect was retained when naked DV RNA was transfected directly into cells. Biosynthetic labeling experiments showed that MPA did not block the initial phase of viral translat …

Specificity of hammerhead ribozyme cleavage.

To be effective in gene inactivation, the hammerhead ribozyme must cleave a complementary RNA target without deleterious effects from cleavi … are shortened at the 5' end. In addition, the specificity of HH16 is improved in the presence of p7 nucleocapsid protein from human immunodeficiency virus (HIV)-1, which accelerates the association and dissociation of RNA helices. These results support the view that the hammerhead has an intrinsic ability to discriminate against incorrect bases, but emphasizes …

Selection of mutants of mumps virus with altered structure and pathogenicity by passage in vivo.

The neurotropic Kilham strain of mumps virus was serially passaged in newborn hamster brains in order to assess possible changes in viral ch … structural proteins of mumps virus marked differences between the variants could be detected in the nucleocapsid (NP) protein and also slight changes in the hemagglutinin-neuraminidase (HN) and phospho- (P) proteins. Differences were found in the preference of the viral variants to infect various regions of the brain. The RK variant heavily infected the caudat …