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1.
Biomed Tech (Berl) ; 2024 Mar 19.
Artigo em Inglês | MEDLINE | ID: mdl-38501753

RESUMO

OBJECTIVES: RFID tags on surgical instruments allow tracking of individual instruments. However, the tags on the instruments can restrict the handling, potentially increasing patient risks. Previous studies analyzed hand contact areas to identify potential locations for tags. However, the studies did not conduct interaction tests using instruments equipped with RFID tags, potentially neglecting the influence of haptic perception. In addition, previous studies required time-consuming evaluations by clinicians. METHODS: Therefore, the present study aims to verify the previous findings in interaction-centered tests with clinicians using real RFID tags on the instruments. Additionally, we had instrument design experts rate RFID tag positions and examined whether they could predict the clinician's preferred tag positions. RESULTS: We found that nearly all RFID tag positions decreased the user satisfaction of clinicians compared to a reference instrument. Compared to previous studies, our study shows that the RFID tag influences the orientations in which an instrument can be comfortably held, which was criticized by clinicians. Instrument design experts could only predict the clinician's preferred tag positions for some instruments. CONCLUSIONS: Therefore, we recommend investigating further changes to instrument design, for what the "ideal" positions proposed by the clinicians in this study can provide initial pointers.

2.
Rev Sci Instrum ; 94(9)2023 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-37682037

RESUMO

Since temperature and its spatial, and temporal variations affect a wide range of physical properties of material systems, they can be used to create reconfigurable spatial structures of various types in physical and biological objects. This paper presents an experimental optical setup for creating tunable two-dimensional temperature patterns on a micrometer scale. As an example of its practical application, we have produced temperature-induced magnetization landscapes in ferrimagnetic yttrium iron garnet films and investigated them using micro-focused Brillouin light scattering spectroscopy. It is shown that, due to the temperature dependence of the magnon spectrum, spatial temperature distributions can be visualized even for microscale thermal patterns.

3.
Viruses ; 14(2)2022 01 27.
Artigo em Inglês | MEDLINE | ID: mdl-35215858

RESUMO

The genus Pestivirus, family Flaviviridae, includes four historically accepted species, i.e., bovine viral diarrhea virus (BVDV)-1 and -2, classical swine fever virus (CSFV), and border disease virus (BDV). A large number of new pestivirus species were identified in recent years. A common feature of most members is the presence of two unique proteins, Npro and Erns, that pestiviruses evolved to regulate the host's innate immune response. In addition to its function as a structural envelope glycoprotein, Erns is also released in the extracellular space, where it is endocytosed by neighboring cells. As an endoribonuclease, Erns is able to cleave viral ss- and dsRNAs, thus preventing the stimulation of the host's interferon (IFN) response. Here, we characterize the basic features of soluble Erns of a large variety of classified and unassigned pestiviruses that have not yet been described. Its ability to form homodimers, its RNase activity, and the ability to inhibit dsRNA-induced IFN synthesis were investigated. Overall, we found large differences between the various Erns proteins that cannot be predicted solely based on their primary amino acid sequences, and that might be the consequence of different virus-host co-evolution histories. This provides valuable information to delineate the structure-function relationship of pestiviral endoribonucleases.


Assuntos
Endorribonucleases/metabolismo , Evasão da Resposta Imune , Imunidade Inata , Pestivirus/imunologia , Pestivirus/patogenicidade , Proteínas do Envelope Viral/metabolismo , Animais , Linhagem Celular , Endocitose , Endorribonucleases/química , Endorribonucleases/genética , Interferons/antagonistas & inibidores , Interferons/biossíntese , Mutação , Proteínas de Resistência a Myxovirus/genética , Proteínas de Resistência a Myxovirus/metabolismo , Pestivirus/metabolismo , RNA de Cadeia Dupla/metabolismo , RNA Viral/metabolismo , Proteínas do Envelope Viral/química , Proteínas do Envelope Viral/genética
4.
J Virol Methods ; 299: 114328, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-34710497

RESUMO

Bovine viral diarrhea virus (BVDV) comprises two species, BVDV-1 and BVDV-2. But given the genetic diversity among pestiviruses, at least 22 subgenotypes are described for BVDV-1 and 3-4 for BVDV-2. Genetic characterization is generally accomplished through complete or partial sequencing and phylogeny, but it is not a reliable method to define antigenic relationships. The traditional method for evaluating antigenic relationships between pestivirus isolates is the virus neutralization (VN) assay, but interpretation of the data to define antigenic relatedness can be difficult to discern for BVDV isolates within the same BVDV species. Data from this study utilized a multivariate analysis for visualization of VN results to analyze the antigenic relationships between US vaccine strains and field isolates from Switzerland, Italy, Brazil, and the UK. Polyclonal sera were generated against six BVDV strains currently contained in vaccine formulations, and each serum was used in VNs to measure the titers against seven vaccine strains (including the six homologous strains) and 23 BVDV field isolates. Principal component analysis (PCA) was performed using VN titers, and results were interpreted from PCA clustering within the PCA dendrogram and scatter plot. The results demonstrated clustering patterns among various isolates suggesting antigenic relatedness. As expected, the BVDV-1 and BVDV-2 isolates did not cluster together and had the greatest spatial distribution. Notably, a number of clusters representing antigenically related BVDV-1 subgroups contain isolates of different subgenotypes. The multivariate analysis may be a method to better characterize antigenic relationships among BVDV isolates that belong to the same BVDV species and do not have distinct antigenic differences. This might be an invaluable tool to ameliorate the composition of current vaccines, which might well be important for the success of any BVDV control program that includes vaccination in its scheme.


Assuntos
Doença das Mucosas por Vírus da Diarreia Viral Bovina , Vírus da Diarreia Viral Bovina Tipo 1 , Vírus da Diarreia Viral Bovina Tipo 2 , Vírus da Diarreia Viral Bovina , Vacinas , Animais , Bovinos , Vírus da Diarreia Viral Bovina Tipo 1/genética , Vírus da Diarreia Viral Bovina Tipo 2/genética , Análise Multivariada , Filogenia
6.
Front Vet Sci ; 8: 681559, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34671657

RESUMO

Bovine viral diarrhoea virus (BVDV) and Border disease virus (BDV) are closely related pestiviruses of cattle and sheep, respectively. Both viruses may be transmitted between either species, but control programs are restricted to BVDV in cattle. In 2008, a program to eradicate bovine viral diarrhoea (BVD) in cattle was started in Switzerland. As vaccination is prohibited, the cattle population is now widely naïve to pestivirus infections. In a recent study, we determined that nearly 10% of cattle are positive for antibodies to BDV. Here, we show that despite this regular transmission of BDV from small ruminants to cattle, we could only identify 25 cattle that were persistently infected with BDV during the last 12 years of the eradication program. In addition, by determining the BVDV and BDV seroprevalence in sheep in Central Switzerland before and after the start of the eradication, we provide evidence that BVDV is transmitted from cattle to sheep, and that the BVDV seroprevalence in sheep significantly decreased after its eradication in cattle. While BDV remains endemic in sheep, the population thus profited at least partially from BVD eradication in cattle. Importantly, on a national level, BVD eradication does not appear to be generally derailed by the presence of pestiviruses in sheep. However, with every single virus-positive cow, it is necessary to consider small ruminants as a potential source of infection, resulting in costly but essential investigations in the final stages of the eradication program.

7.
Front Vet Sci ; 8: 702730, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34557540

RESUMO

Bovine viral diarrhoea virus (BVDV) and related ruminant pestiviruses occur worldwide and cause considerable economic losses in livestock and severely impair animal welfare. Switzerland started a national mandatory control programme in 2008 aiming to eradicate BVD from the Swiss cattle population. The peculiar biology of pestiviruses with the birth of persistently infected (PI) animals upon in utero infection in addition to transient infection of naïve animals requires vertical and horizontal transmission to be taken into account. Initially, every animal was tested for PI within the first year, followed by testing for the presence of virus in all newborn calves for the next four years. Prevalence of calves being born PI thus diminished substantially from around 1.4% to <0.02%, which enabled broad testing for the virus to be abandoned and switching to economically more favourable serological surveillance with vaccination being prohibited. By the end of 2020, more than 99.5% of all cattle farms in Switzerland were free of BVDV but eliminating the last remaining PI animals turned out to be a tougher nut to crack. In this review, we describe the Swiss BVD eradication scheme and the hurdles that were encountered and still remain during the implementation of the programme. The main challenge is to rapidly identify the source of infection in case of a positive result during antibody surveillance, and to efficiently protect the cattle population from re-infection, particularly in light of the endemic presence of the related pestivirus border disease virus (BDV) in sheep. As a consequence of these measures, complete eradication will (hopefully) soon be achieved, and the final step will then be the continuous documentation of freedom of disease.

8.
Redox Biol ; 47: 102133, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-34562872

RESUMO

The respiratory burst of phagocytes is essential for human survival. Innate immune defence against pathogens relies strongly on reactive oxygen species (ROS) production by the NADPH oxidase (NOX2). ROS kill pathogens while the translocation of electrons across the plasma membrane via NOX2 depolarizes the cell. Simultaneously, protons are released into the cytosol. Here, we compare freshly isolated human polymorphonuclear leukocytes (PMN) to the granulocytes-like cell line PLB 985. We are recording ROS production while inhibiting the charge compensating and pH regulating voltage-gated proton channel (HV1). The data suggests that human PMN and the PLB 985 generate ROS via a general mechanism, consistent of NOX2 and HV1. Additionally, we advanced a mathematical model based on the biophysical properties of NOX2 and HV1. Our results strongly suggest the essential interconnection of HV1 and NOX2 during the respiratory burst of phagocytes. Zinc chelation during the time course of the experiments postulates that zinc leads to an irreversible termination of the respiratory burst over time. Flow cytometry shows cell death triggered by high zinc concentrations and PMA. Our data might help to elucidate the complex interaction of proteins during the respiratory burst and contribute to decipher its termination.


Assuntos
Neutrófilos , Explosão Respiratória , Humanos , Canais Iônicos/metabolismo , NADPH Oxidases/metabolismo , Neutrófilos/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Zinco
9.
Viruses ; 13(8)2021 08 10.
Artigo em Inglês | MEDLINE | ID: mdl-34452446

RESUMO

The genus Pestivirus, family Flaviviridae, includes four economically important viruses of livestock, i.e., bovine viral diarrhea virus-1 (BVDV-1) and -2 (BVDV-2), border disease virus (BDV) and classical swine fever virus (CSFV). Erns and Npro, both expressed uniquely by pestiviruses, counteract the host's innate immune defense by interfering with the induction of interferon (IFN) synthesis. The structural envelope protein Erns also exists in a soluble form and, by its endoribonuclease activity, degrades immunostimulatory RNA prior to their activation of pattern recognition receptors. Here, we show that at least three out of four positively-charged residues in the C-terminal glycosaminoglycan (GAG)-binding site of BVDV-Erns are required for efficient cell entry, and that a positively charged region more upstream is not involved in cell entry but rather in RNA-binding. Moreover, the C-terminal domain on its own determines intracellular targeting, as GFP fused to the C-terminal amino acids of Erns was found at the same compartments as wt Erns. In summary, RNase activity and uptake into cells are both required for Erns to act as an IFN antagonist, and the C-terminal amphipathic helix containing the GAG-binding site determines the efficiency of cell entry and its intracellular localization.


Assuntos
Aminoácidos/química , Endorribonucleases/metabolismo , Evasão da Resposta Imune , Pestivirus/genética , Pestivirus/fisiologia , Internalização do Vírus , Aminoácidos/metabolismo , Animais , Bovinos , Células Cultivadas , Endorribonucleases/farmacologia , Interações entre Hospedeiro e Microrganismos , Pestivirus/enzimologia , Pestivirus/imunologia , RNA Viral/genética , Conchas Nasais/citologia , Conchas Nasais/efeitos dos fármacos , Conchas Nasais/virologia , Proteínas do Envelope Viral/metabolismo
10.
Transbound Emerg Dis ; 68(2): 233-239, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-32386079

RESUMO

Bovine viral diarrhoea virus (BVDV) is a pestivirus that affects both cattle and sheep, causing an array of clinical signs, which include abortions and malformations in the offspring. Manufacturing of modified live virus (MLV) vaccines often includes the use of bovine-derived products, which implies a risk of contamination with viable BVDV. Recently, the circulation of a specific strain of BVDV 2b among Spanish sheep flocks, associated with outbreaks of abortions and malformations, and whose origin was not determined, has been observed. On February 2018, a MLV orf vaccine was applied to a 1,600 highly prolific sheep flock in the Northeast of Spain that included 550 pregnant ewes. In May 2018, during the lambing season, an unusual high rate (72.7%) of abortions, stillbirths, congenital malformations and neurological signs in the offspring was observed. It was estimated that about 1,000 lambs were lost. Three 1- to 3-day-old affected lambs and a sealed vial of the applied vaccine were studied. Lambs showed variable degrees of central nervous system malformations and presence of pestiviral antigen in the brain. Molecular studies demonstrated the presence of exactly the same BVDV 2b in the tissues of the three lambs and in the orf vaccine, thus pointing to a pestivirus contamination in the applied vaccine as the cause of the outbreak. Interestingly, sequencing at the 5'-untranslated region-(UTR) of the contaminating virus showed a complete match with the virus described in the previously reported outbreaks in Spain, thus indicating that the same contaminated vaccine could have also played a role in those cases. This communication provides a clear example of the effects of the application of this contaminated product in a sheep flock. The information presented here can be of interest in putative future cases of suspected circulation of this or other BVDV strains in ruminants.


Assuntos
Aborto Animal/epidemiologia , Anormalidades Congênitas/veterinária , Surtos de Doenças/veterinária , Doenças dos Ovinos/epidemiologia , Natimorto/veterinária , Vacinas Virais/efeitos adversos , Animais , Anormalidades Congênitas/epidemiologia , Vírus da Diarreia Viral Bovina Tipo 2/imunologia , Ovinos , Carneiro Doméstico , Espanha/epidemiologia , Natimorto/epidemiologia
11.
Viruses ; 11(7)2019 07 17.
Artigo em Inglês | MEDLINE | ID: mdl-31319583

RESUMO

In 2015, a new pestivirus was described in pig sera in the United States. This new "atypical porcine pestivirus" (APPV) was later associated with congenital tremor (CT) in newborn piglets. The virus appears to be distributed worldwide, but the limited knowledge of virus diversity and the use of various diagnostic tests prevent direct comparisons. Therefore, we developed an APPV-specific real-time RT-PCR assay in the 5'UTR of the viral genome to investigate both retro- and prospectively the strains present in Switzerland and their prevalence in domestic pigs. Overall, 1080 sera obtained between 1986 and 2018 were analyzed, revealing a virus prevalence of approximately 13% in pigs for slaughter, whereas it was less than 1% in breeding pigs. In the prospective study, APPV was also detected in piglets displaying CT. None of the samples could detect the Linda virus, which is another new pestivirus recently reported in Austria. Sequencing and phylogenetic analysis revealed a broad diversity of APP viruses in Switzerland that are considerably distinct from sequences reported from other isolates in Europe and overseas. This study indicates that APPV has already been widely circulating in Switzerland for many years, mainly in young animals, with 1986 being the earliest report of APPV worldwide.


Assuntos
Infecções por Pestivirus/veterinária , Pestivirus/classificação , Pestivirus/genética , Doenças dos Suínos/epidemiologia , Doenças dos Suínos/virologia , Regiões 5' não Traduzidas , Animais , Genoma Viral , Pestivirus/isolamento & purificação , Filogenia , Prevalência , Vigilância em Saúde Pública , RNA Viral , Reação em Cadeia da Polimerase em Tempo Real , Sus scrofa , Suínos , Suíça/epidemiologia
12.
Vet J ; 246: 12-20, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30902184

RESUMO

Within the family Flaviviridae, viruses within the genus Pestivirus, such as Border disease virus (BDV) of sheep, can cause great economic losses in farm animals. Originally, the taxonomic classification of pestiviruses was based on the host species they were isolated from, but today, it is known that many pestiviruses exhibit a broad species tropism. This review provides an overview of BDV infection in cattle. The clinical, hematological and pathological-anatomical findings in bovines that were transiently or persistently infected with BDV largely resemble those in cattle infected with the closely related pestivirus bovine viral diarrhoea virus (BVDV). Accordingly, the diagnosis of BDV infection can be challenging, as it must be differentiated from various pestiviruses in cattle. The latter is very relevant in countries with control programs to eradicate BVDV in Bovidae, as in most circumstances, pestivirus infections in sheep, which act as reservoir for BDV, are not included in the eradication scheme. Interspecies transmission of BDV between sheep and cattle occurs regularly, but BDV in cattle appears to be of minor general importance. Nevertheless, BDV outbreaks at farm or local level can be very costly.


Assuntos
Doença da Fronteira/transmissão , Doenças dos Bovinos/transmissão , Animais , Doença da Fronteira/epidemiologia , Doença da Fronteira/patologia , Doença da Fronteira/prevenção & controle , Vírus da Doença da Fronteira/classificação , Bovinos , Doenças dos Bovinos/epidemiologia , Doenças dos Bovinos/prevenção & controle , Doenças dos Bovinos/virologia , Ovinos , Doenças dos Ovinos/transmissão
13.
BMC Genomics ; 20(1): 15, 2019 Jan 08.
Artigo em Inglês | MEDLINE | ID: mdl-30621583

RESUMO

BACKGROUND: Pathogens stimulate immune functions of macrophages. Macrophages are a key sentinel cell regulating the response to pathogenic ligands and orchestrating the direction of the immune response. Our study aimed at investigating the early transcriptomic changes of bovine macrophages (Bomacs) in response to stimulation with CpG DNA or polyI:C, representing bacterial and viral ligands respectively, and performed transcriptomics by RNA sequencing (RNASeq). KEGG, GO and IPA analytical tools were used to reconstruct pathways, networks and to map out molecular and cellular functions of differentially expressed genes (DE) in stimulated cells. RESULTS: A one-way ANOVA analysis of RNASeq data revealed significant differences between the CpG DNA and polyI:C-stimulated Bomac. Of the 13,740 genes mapped to the bovine genome, 2245 had p-value ≤0.05, deemed as DE. At 6 h post stimulation of Bomac, poly(I:C) induced a very different transcriptomic profile from that induced by CpG DNA. Whereas, 347 genes were upregulated and 210 downregulated in response to CpG DNA, poly(I:C) upregulated 761 genes and downregulated 414 genes. The topmost DE genes in poly(I:C)-stimulated cells had thousand-fold changes with highly significant p-values, whereas in CpG DNA stimulated cells had 2-5-fold changes with less stringent p-values. The highest DE genes in both stimulations belonged to the TNF superfamily, TNFSF18 (CpG) and TNFSF10 (poly(I:C)) and in both cases the lowest downregulated gene was CYP1A1. CpG DNA highly induced canonical pathways that are unrelated to immune response in Bomac. CpG DNA influenced expression of genes involved in molecular and cellular functions in free radical scavenging. By contrast, poly(I:C) highly induced exclusively canonical pathways directly related to antiviral immune functions mediated by interferon signalling genes. The transcriptomic profile after poly(I:C)-stimulation was consistent with induction of TLR3 signalling. CONCLUSION: CpG DNA and poly(I:C) induce different early transcriptional landscapes in Bomac, but each is suited to a specific function of macrophages during interaction with pathogens. Poly(I:C) influenced antiviral response genes, whereas CpG DNA influenced genes important for phagocytic processes. Poly(I:C) was more potent in setting the inflammatory landscape desirable for an efficient immune response against virus infection.


Assuntos
Sequenciamento de Nucleotídeos em Larga Escala , Macrófagos/metabolismo , Moléculas com Motivos Associados a Patógenos , Transcriptoma/genética , Animais , Bovinos , Linhagem Celular , Ilhas de CpG/genética , Citocromo P-450 CYP1A1/genética , Perfilação da Expressão Gênica , Genoma/genética , Ligantes , Macrófagos/microbiologia , Macrófagos/virologia , Poli I-C/genética , Fatores de Necrose Tumoral/genética
14.
Transbound Emerg Dis ; 66(2): 640-652, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30415496

RESUMO

The significant economic impacts of bovine viral diarrhoea (BVD) virus have prompted many countries worldwide to embark on regional or national BVD eradication programmes. Unlike other infectious diseases, BVD control is highly feasible in cattle production systems because the pathogenesis is well understood and there are effective tools to break the disease transmission cycle at the farm and industry levels. Coordinated control approaches typically involve directly testing populations for virus or serological screening of cattle herds to identify those with recent exposure to BVD, testing individual animals within affected herds to identify and eliminate persistently infected (PI) cattle, and implementing biosecurity measures such as double-fencing shared farm boundaries, vaccinating susceptible breeding cattle, improving visitor and equipment hygiene practices, and maintaining closed herds to prevent further disease transmission. As highlighted by the recent DISCONTOOLS review conducted by a panel of internationally recognized experts, knowledge gaps in the control measures are primarily centred around the practical application of existing tools rather than the need for creation of new tools. Further research is required to: (a) determine the most cost effective and socially acceptable means of applying BVD control measures in different cattle production systems; (b) identify the most effective ways to build widespread support for implementing BVD control measures from the bottom-up through farmer engagement and from the top-down through national policy; and (c) to develop strategies to prevent the reintroduction of BVD into disease-free regions by managing the risks associated with the movements of animals, personnel and equipment. Stronger collaboration between epidemiologists, economists and social scientists will be essential for progressing efforts to eradicate BVD from more countries worldwide.


Assuntos
Doença das Mucosas por Vírus da Diarreia Viral Bovina/prevenção & controle , Vírus da Diarreia Viral Bovina/fisiologia , Erradicação de Doenças/métodos , Síndrome Hemorrágica Bovina/prevenção & controle , Animais , Bovinos , Análise Custo-Benefício , Erradicação de Doenças/economia
15.
PLoS One ; 13(12): e0207604, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30517140

RESUMO

The first records of smallpox and rabies date back thousands of years and foot-and-mouth disease in cattle was described in the 16th century. These diseases stood out by their distinct signs, dramatic way of transmission from rabid dogs to humans, and sudden appearance in cattle herds. By contrast, infectious diseases that show variable signs and affect few individuals were identified only much later. Bovine viral diarrhea (BVD), endemic in cattle worldwide, was first described in 1946, together with the eponymous RNA virus as its cause. There is general agreement that BVD was not newly emerging at that time, but its history remains unknown. A search for associations between the nucleotide sequences of over 7,000 BVD viral strains obtained during a national campaign to eradicate BVD and features common to the hosts of these strains enabled us to trace back in time the presence of BVD in the Swiss cattle population. We found that animals of the two major traditional cattle breeds, Fleckvieh and Swiss Brown, were infected with strains of only four different subgenotypes of BVDV-1. The history of these cattle breeds and the events that determined the current distribution of the two populations are well documented. Specifically, Fleckvieh originates from the Bernese and Swiss Brown from the central Alps. The spread to their current geographic distribution was determined by historic events during a major expansion of the Swiss Confederation during the 15th and 16th centuries. The association of the two cattle populations with different BVD viral subgenotypes may have been preserved by a lack of cattle imports, trade barriers within the country, and unique virus-host interactions. The congruent traces of history in the distribution of the two cattle breeds and distinct viral subgenotypes suggests that BVD may have been endemic in Switzerland for at least 600 years.


Assuntos
Doença das Mucosas por Vírus da Diarreia Viral Bovina/genética , Doença das Mucosas por Vírus da Diarreia Viral Bovina/história , Vírus da Diarreia Viral Bovina/genética , Animais , Sequência de Bases/genética , Bovinos , Diarreia/veterinária , Diarreia/virologia , Vírus da Diarreia Viral Bovina/patogenicidade , Variação Genética/genética , História do Século XV , História do Século XVI , História Medieval , Filogeografia , Vírus de RNA/genética , Suíça
16.
Artigo em Inglês | MEDLINE | ID: mdl-30181371

RESUMO

The virus family Flaviviridae encompasses several viruses, including (re)emerging viruses which cause widespread morbidity and mortality throughout the world. Members of this virus family are positive-strand RNA viruses and replicate their genome in close association with reorganized intracellular host cell membrane compartments. This evolutionarily conserved strategy facilitates efficient viral genome replication and contributes to evasion from host cell cytosolic defense mechanisms. We have previously described the identification of a small-compound inhibitor, K22, which exerts a potent antiviral activity against a broad range of coronaviruses by targeting membrane-bound viral RNA replication. To analyze the antiviral spectrum of this inhibitor, we assessed the inhibitory potential of K22 against several members of the Flaviviridae family, including the reemerging Zika virus (ZIKV). We show that ZIKV is strongly affected by K22. Time-of-addition experiments revealed that K22 acts during a postentry phase of the ZIKV life cycle, and combination regimens of K22 together with ribavirin (RBV) or interferon alpha (IFN-α) further increased the extent of viral inhibition. Ultrastructural electron microscopy studies revealed severe alterations of ZIKV-induced intracellular replication compartments upon infection of K22-treated cells. Importantly, the antiviral activity of K22 was demonstrated against several other members of the Flaviviridae family. It is tempting to speculate that K22 exerts its broad antiviral activity against several positive-strand RNA viruses via a similar mechanism and thereby represents an attractive candidate for development as a panviral inhibitor.


Assuntos
Antivirais/farmacologia , Membrana Celular/efeitos dos fármacos , Infecções por Flaviviridae/tratamento farmacológico , Flaviviridae/efeitos dos fármacos , Aedes , Animais , Linhagem Celular , Membrana Celular/virologia , Chlorocebus aethiops , Infecções por Flaviviridae/virologia , Humanos , Interferon-alfa/farmacologia , RNA Viral/genética , Ribavirina/farmacologia , Células Vero , Replicação Viral/efeitos dos fármacos
17.
BMC Vet Res ; 14(1): 182, 2018 06 11.
Artigo em Inglês | MEDLINE | ID: mdl-29890987

RESUMO

The original article [1] contained an error whereby a co-author, Sarah Züblin had their name displayed incorrectly. This error has now been corrected.

18.
J Phys Condens Matter ; 30(26): 265101, 2018 Jul 04.
Artigo em Inglês | MEDLINE | ID: mdl-29775180

RESUMO

We investigate the P(NDI2OD-T2) photophysical properties via absorbance and fluorescence spectroscopy, in association with the experimental approach baptized Stokes Spectroscopy, which provides valuable material information through the acquisition and analysis of the fluorescence polarization degree. By changing solvents and using different samples such as solutions, thick, and thin films, it is possible to control the polarization degree spectrum associated to the fluorescence emitted by the polymer's isolated chains and aggregates. We show that the polarization degree could become a powerful tool to obtain information related to the samples morphology, which is connected to their microscopic structure. Moreover, the polarization degree spectra suggest that depolarization effects linked to energy and charge transfer mechanisms are likely taking place. Our findings indicate that P(NDI2OD-T2) polymers are excellent candidates for the advancement of organic technologies that rely on the emission and detection of polarized lights.

19.
BMC Vet Res ; 14(1): 159, 2018 May 16.
Artigo em Inglês | MEDLINE | ID: mdl-29769076

RESUMO

BACKGROUND: This study examined various health variables in cows after artificial insemination with Border disease virus (BDV)-infected semen and the occurrence of persistent infection in ensuing fetuses. Five cows were inseminated (day 0) with BDV-infected semen as well as with semen from a fertile Eringer bull. One cow, inseminated with virus-free semen only, served as a control. Clinical examination, assessment of eating and rumination activities, measurement of intraruminal temperature and leukocyte count were used to monitor the health of the cows. Blood samples were collected at regular intervals for the detection of viral RNA and antibodies against BDV, and the cows were slaughtered on day 56. The uteri, placentae and fetuses were examined macroscopically, histologically, immunohistochemically and by means of molecular methods for the presence of pestiviruses. RESULTS: The demeanour, eating and rumination activities and intraruminal temperature were not affected by insemination with BDV-infected semen, whereas the total leukocyte and lymphocyte counts dropped transiently and were significantly lower on day 6 than on day 0. Seroconversion occurred by day 28 in the five infected cows but not in the control cow. The uteri, placentae and fetuses had no macroscopic or histological lesions, and immunohistochemical examination and RT-PCR were negative for pestiviruses. CONCLUSIONS: The findings showed that cows inseminated with BDV-infected semen seroconverted and fetuses thus produced were not persistently infected. Transmission of BDV to cattle through infected semen, therefore, seems to be of minor importance.


Assuntos
Doença da Fronteira/transmissão , Vírus da Doença da Fronteira , Doenças dos Bovinos/transmissão , Doenças Fetais/veterinária , Inseminação Artificial/veterinária , Sêmen/virologia , Soroconversão , Animais , Doença da Fronteira/sangue , Doença da Fronteira/imunologia , Doença da Fronteira/virologia , Vírus da Doença da Fronteira/isolamento & purificação , Bovinos , Doenças dos Bovinos/sangue , Doenças dos Bovinos/imunologia , Doenças dos Bovinos/virologia , Feminino , Doenças Fetais/sangue , Doenças Fetais/imunologia , Doenças Fetais/virologia , Transmissão Vertical de Doenças Infecciosas/veterinária , Inseminação Artificial/efeitos adversos , Contagem de Leucócitos/veterinária , Masculino , Contagem de Plaquetas , Gravidez
20.
Sci Rep ; 8(1): 8226, 2018 05 29.
Artigo em Inglês | MEDLINE | ID: mdl-29844335

RESUMO

The glycoprotein Erns plays a central role in the biology of the pestivirus bovine viral diarrhea virus (BVDV). This soluble endonuclease mediates the escape from an interferon (IFN) response in the infected fetus, thereby permitting the establishment of persistent infection. Viral single-stranded (ss) and double-stranded (ds) RNA act as potent IFN inducing signals and we previously showed that Erns efficiently cleaves these substrates, thereby inhibiting an IFN response that is crucial for successful fetal infection. Considering that a large variety of RNases and DNases require dimerisation to cleave double-stranded substrates, the activity of Erns against dsRNA was postulated to depend on homodimer formation mediated by disulfide bonds involving residue Cys171. Here, we show that monomeric Erns is equally able to cleave dsRNA and to inhibit dsRNA-induced IFN synthesis as the wild-type form. Furthermore, both forms were able to degrade RNA within a DNA/RNA- as well as within a methylated RNA/RNA-hybrid, with the DNA and the methylated RNA strand being resistant to degradation. These results support our model that Erns acts as 'nicking endoribonuclease' degrading ssRNA within double-stranded substrates. This efficiently prevents the activation of IFN and helps to maintain a state of innate immunotolerance in persistently infected animals.


Assuntos
Vírus da Diarreia Viral Bovina/enzimologia , Endorribonucleases/metabolismo , RNA de Cadeia Dupla/metabolismo , Animais , Doença das Mucosas por Vírus da Diarreia Viral Bovina/imunologia , Doença das Mucosas por Vírus da Diarreia Viral Bovina/virologia , Bovinos , Doenças dos Bovinos/imunologia , Doenças dos Bovinos/virologia , Vírus da Diarreia Viral Bovina/genética , Dimerização , Imunidade Inata , Interferons/biossíntese , RNA de Cadeia Dupla/genética , RNA Viral/genética , RNA Viral/metabolismo , Especificidade por Substrato , Proteínas Virais/genética
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