104 research outputs found

    Genetic Interference and Receptor Biology of Neglected Influenza Viruses

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    Influenza B virus (IBV) is an important pathogen that infects humans and causes seasonal influenza epidemics. By using next-generation sequencing (NGS) approach, we analyzed total mRNAs extracted from A549 cells infected with B/Brisbane/60/2008, and identified four defective genomes in IBV with two from the polymerase basic subunit 1 (PB1) segment and the other two from the matrix (M) segment. Each of them can potently inhibit the replication of IBV. One derived from PB1 segment was able to interfere modestly with influenza A virus (IAV) replication. The productions of the four defective RNAs are not dependent on the cell types. The important initial insights into IBV defective genomes can be further explored toward better understanding of the replication, pathogenesis, and evolution of IBV. The second study demonstrated that influenza D virus (IDV) is more efficient in recognizing both human Neu5,9Ac2 and non-human Neu5Gc9Ac receptors than influenza C virus (ICV). ICV prefers human Neu5,9Ac2 over non-human Neu5Gc9Ac. The results reveal that IDV and ICV diverge in communicating with both O-acetyl group at the C9 position and acetyl/glycolyl groups at the C5 position in terminal 9-carbon SAs. Our findings provide evidence that IDV has acquired the unique ability to infect and transmit among agricultural animals that are enriched in Neu5Gc9Ac, in addition to pose a zoonotic risk to humans only expressing Neu5,9Ac2. Characterization of a contemporary human ICV is needed. C/Victoria/2/2012 (C/Vic) isolated in 2012 was used in this study. Phylogenetic studies demonstrated that C/Vic is a reassortant virus composed of segments derived from multiple ICV lineages or strains, which evolved independently. We identified two mutations in the 170-loop of the HEF protein around the receptor binding pocket as a possible antigenic determinant responsible for the discrepant hemagglutinin inhibition results. C/Vic replicates more efficiently at the cool temperature, which should be further investigated toward elucidating the molecular determinants of temperature-dependent growth. The study on this contemporary ICV shall aid in the further investigation of biology, evolution, and pathogenesis of ICV

    Macerals of lignite and the effect of alkali treatment on the structure and combustion performance of lignite

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    Suppressing the spontaneous combustion of lignite is of great significance for safe transportation and efficient utilization of lignite. Taking the Shengli lignite as the research object, two different macerals, inertinite and huminite, were selected by optical microscope, and treated with NaOH respectively to study the relationship between the structure and combustion reaction performance of different macerals and lignite treated with NaOH. The structure of the prepared coal samples was characterized by SEM-EDS, XPS, FT-IR, XRD and Raman, and the changes of the main functional groups were analyzed. The effect of NaOH treatment on the combustion performance of different maceral lignite was investigated by TGA. The results showed that the ignition temperature of huminite lignite was about 10 ℃ earlier than that of inertinite, but the comprehensive combustion characteristic index of inertinite lignite was slightly higher than that of huminite. After the NaOH treatment, the lignite of different macerals showed a hysteresis of combustion, there were two obvious weight losses in the range of 200−500 ℃ and 650−800 ℃, respectively, and the mass loss was mainly concentrated in the second weight loss, in particular, the effect of huminite lignite was more significant, and the temperature corresponding to the maximum combustion reaction rate was about 60 ℃ behind that of inertinite. The kinetic analysis of the combustion process of the coal samples showed that the activation energy of combustion reaction of lignite with different macerals significantly increased after the NaOH treatment, and the huminite lignite was higher than that of inertinite lignite. The XPS/FT-IR results revealed that the contents of carboxylic oxygen-containing functional groups in different macerals of lignite treated by NaOH decreased, the main reason is that in the process of NaOH treatment, Na+ interacted with the carboxylic oxygen-containing functional groups in lignite to form the sodium carboxylate structure, and the relative amount of the sodium carboxylate structure in huminite coal was relatively large. It is believed that the inhibitory effect on the combustion of lignite with different macerals is attributed to the stability of the sodium carboxylate structure, and the number of the sodium carboxylate structure formed by combining with Na is the main reason for the difference in its combustion performance. The XRD/Raman analysis indicates that the formation of the sodium carboxylate structure in lignite leads to the increase of the order degree of carbon microcrystalline structure, and the order degree of huminite lignite is higher than that in inertinite

    Isolation of a Novel Swine Influenza Virus from Oklahoma in 2011 Which Is Distantly Related to Human Influenza C Viruses

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    Of the Orthomyxoviridae family of viruses, only influenza A viruses are thought to exist as multiple subtypes and has nonhuman maintenance hosts. In April 2011, nasal swabs were collected for virus isolation from pigs exhibiting influenza-like illness. Subsequent electron microscopic, biochemical, and genetic studies identified an orthomyxovirus with seven RNA segments exhibiting approximately 50% overall amino acid identity to human influenza C virus. Based on its genetic organizational similarities to influenza C viruses this virus has been provisionally designated C/Oklahoma/1334/2011 (C/OK). Phylogenetic analysis of the predicted viral proteins found that the divergence between C/OK and human influenza C viruses was similar to that observed between influenza A and B viruses. No cross reactivity was observed between C/OK and human influenza C viruses using hemagglutination inhibition (HI) assays. Additionally, screening of pig and human serum samples found that 9.5% and 1.3%, respectively, of individuals had measurable HI antibody titers to C/OK virus. C/OK virus was able to infect both ferrets and pigs and transmit to naive animals by direct contact. Cell culture studies showed that C/ OK virus displayed a broader cellular tropism than a human influenza C virus. The observed difference in cellular tropism was further supported by structural analysis showing that hemagglutinin esterase (HE) proteins between two viruses have conserved enzymatic but divergent receptor-binding sites. These results suggest that C/OK virus represents a new subtype of influenza C viruses that currently circulates in pigs that has not been recognized previously. The presence of multiple subtypes of co-circulating influenza C viruses raises the possibility of reassortment and antigenic shift as mechanisms of influenza C virus evolution

    A novel and highly efficient Zr-containing catalyst supported by biomass-derived sodium carboxymethyl cellulose for hydrogenation of furfural

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    Functional use of biomass based on its structural properties is an efficient approach for the valuable utilization of biomass resources. In this work, carboxymethyl cellulose zirconium-based catalyst (Zr-CMC) was constructed by the coordination between the carboxylic groups in sodium carboxymethyl cellulose (CMC-Na) with transition metal Zr4+. The prepared catalyst was applied into the synthesis of furfuryl alcohol (FAL) by catalytic transfer hydrogenation of biomass-derived furfural (FF) using isopropanol as hydrogen donor. Both the preparation conditions and the reaction conditions of Zr-CMC catalyst were investigated and optimized. The results showed that Zr-CMC was efficient for the reaction with the FF conversion, FAL yield and selectivity reaching to 92.5%, 91.5 %, and 99.0%, respectively, under the mild conditions (90°C). Meanwhile, the Zr-CMC catalyst could be reused at least for five times without obvious decrease in efficiency, indicating the catalyst had excellent stability. With the advantages of sustainable raw materials, high efficiency, and excellent stability, the prepared catalyst is potential for application in the field of biomass conversion

    Characterization of a Novel Influenza Virus in Cattle and Swine: Proposal for a New Genus in the Orthomyxoviridae Family

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    We have recently reported the isolation of a novel virus, provisionally designated C/swine/Oklahoma/1334/2011 (C/OK), with 50% overall homology to human influenza C viruses (ICV), from a pig in Oklahoma. Deep RNA sequencing of C/OK virus found a matrix 1 (M1) protein expression strategy that differed from that of ICV. The novelty of C/OK virus prompted us to investigate whether C/OK virus could exist in a nonswine species. Significantly, we found that C/OK virus was widespread in U.S. bovine herds, as demonstrated by reverse transcription (RT)-PCR and serological assays. Genome sequencing of three bovine viruses isolated from two herds in different states further confirmed these findings. To determine whether swine/bovine C/OK viruses can undergo reassortment with human ICV, and to clarify the taxonomic status of C/OK, in vitro reassortment and serological typing by agar gel immunodiffusion (AGID) were conducted. In vitro reassortment using two human ICV and two swine and bovine C/OK viruses demonstrated that human ICV and C/OK viruses were unable to reassort and produce viable progeny. Antigenically, no cross-recognition of detergent split virions was observed in AGID between human and nonhuman viruses by using polyclonal antibodies that were reactive to cognate antigens. Taken together, these results demonstrate that C/OK virus is genetically and antigenically distinct from ICV. The classification of the new virus in a separate genus of the Orthomyxoviridae family is proposed. The finding of C/OK virus in swine and bovine indicates that this new virus may spread and establish infection in other mammals, including humans

    Influenza C and D Viruses Demonstrated a Differential Respiratory Tissue Tropism in a Comparative Pathogenesis Study in Guinea Pigs

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    Influenza C virus (ICV) is increasingly associated with community-acquired pneumonia (CAP) in children and its disease severity is worse than the influenza B virus, but similar to influenza A virus associated CAP. Despite the ubiquitous infection landscape of ICV in humans, little is known about its replication and pathobiology in animals. The goal of this study was to understand the replication kinetics, tissue tropism, and pathogenesis of human ICV (huICV) in comparison to the swine influenza D virus (swIDV) in guinea pigs. Intranasal inoculation of both viruses did not cause clinical signs, however, the infected animals shed virus in nasal washes. The huICV replicated in the nasal turbinates, soft palate, and trachea but not in the lungs while swIDV replicated in all four tissues. A comparative analysis of tropism and pathogenesis of these two related seven-segmented influenza viruses revealed that swIDV-infected animals exhibited broad tissue tropism with an increased rate of shedding on 3, 5, and 7 dpi and high viral loads in the lungs compared to huICV. Seroconversion occurred late in the huICV group at 14 dpi, while swIDV-infected animals seroconverted at 7 dpi. Guinea pigs infected with huICV exhibited mild to moderate inflammatory changes in the epithelium of the soft palate and trachea, along with mucosal damage and multifocal alveolitis in the lungs. In summary, the replication kinetics and pathobiological characteristics of ICV in guinea pigs agree with the clinical manifestation of ICV infection in humans, and hence guinea pigs could be used to study these distantly related influenza viruses
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