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1.
Res Vet Sci ; 165: 105052, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37864907

RESUMO

Toxoplasma gondii is a major foodborne zoonotic pathogen that can be transmitted through the consumption of raw or undercooked meat of small ruminants, among others. Serology has been suggested as an epidemiological indicator and several tests are available nowadays. However, there is no comparative study with the most used ones. Therefore, the objective of this study was to develop and validate two in-house tests (Western blot -TgSALUVET WB- and ELISA -TgSALUVET ELISA 2.0-) and perform a comparative study including such tests and four commercial ELISA kits (IDScreen®, PrioCHECK®, Pigtype® and IDEXX). First, a specific pattern of recognition of immunodominant antigens by TgSALUVET WB was determined with serum panels of noninfected sheep and sheep infected with T. gondii or Neospora caninum. Next, TgSALUVET WB was used as a reference to preliminary validate TgSALUVET ELISA 2.0 using sera from sheep and goats naturally infected with T. gondii. Then, the abovementioned sheep serum panels were analyzed by all tests and subjected to TG-ROC analyses and agreement tests, and cross-reactivity with the anti-N. caninum IgGs was studied. All the techniques were accurate enough for the cutoff values initially suggested with all serum panels (Se and Sp ≥ 94%), except for PrioCHECK®, which showed 83% Sp. However, a cutoff readjustment improved their diagnostic performance. Additionally, cross-reactions between anti-N. caninum antibodies and T. gondii antigens were detected with all tests. Thus, a second cutoff readjustment was carried out and the use of both readjusted cutoff values is recommended to obtain comparable data and avoid false-positive results.


Assuntos
Coccidiose , Doenças das Cabras , Neospora , Toxoplasma , Toxoplasmose Animal , Ovinos , Animais , Toxoplasmose Animal/diagnóstico , Anticorpos Antiprotozoários , Ruminantes , Cabras , Ensaio de Imunoadsorção Enzimática/veterinária , Testes Sorológicos/veterinária , Estudos Soroepidemiológicos , Coccidiose/diagnóstico , Coccidiose/veterinária , Doenças das Cabras/diagnóstico
2.
Appl Mater Today ; 32: 101828, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-37317691

RESUMO

Commercial polyurethane (PU) coating formulations have been modified with 1-(hydroxymethyl)-5,5-dimethylhydantoin (HMD) both in bulk (0.5 and 1% w/w) and onto the coatings surface as an N-halamine precursor, to obtain clear coatings with high virucidal activity. Upon immersion in diluted chlorine bleaching, the hydantoin structure on the grafted PU membranes was transformed into N-halamine groups, with a high surface chlorine concentration (40-43µg/cm2). Fourier transform infrared spectroscopy (FTIR) spectroscopy, thermogravimetric analysis (TGA), energy-dispersive X-ray (EDX), X-ray photoelectron spectroscopy (XPS) and iodometric titration were used to characterize the coatings and quantify the chlorine contents of the PU membranes after chlorination. Biological evaluation of their activity against Staphylococcus aureus (Gram-positive bacteria) and human coronaviruses HCoV-229E and SARS-CoV-2 was performed, and high inactivation of these pathogens was observed after short contact times. The inactivation of HCoV-229E was higher than 98% for all modified samples after just 30 minutes, whereas it was necessary 12 hours of contact time for complete inactivation of SARS-CoV-2. The coatings were fully rechargeable by immersion in diluted chlorine bleach (2% v/v) for at least 5 chlorination-dechlorination cycles. Moreover, the performance of the antivirus efficiency of the coatings is considered as long-lasting, because experiments of reinfection of the coatings with HCoV-229E coronavirus did not show any loss of the virucidal activity after three consecutive infection cycles without reactivation of the N-halamine groups.

3.
ACS Appl Mater Interfaces ; 15(18): 22580-22589, 2023 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-37116104

RESUMO

The current global pandemic due to the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) virus has demonstrated the necessity to develop novel materials with antimicrobial and antiviral activities to prevent the infection. One significant route for the spread of diseases is by the transmission of the virus through contact with contaminated surfaces. Antiviral surface treatments can help to reduce or even avoid these hazards. In particular, the development of active-virucidal fabrics or paints represents a very important challenge with multiple applications in hospitals, public transports, or schools. Modern, cutting-edge methods for creating antiviral surface coatings use either materials with a metal base or sophisticated synthetic polymers. Even if these methods are effective, they will still face significant obstacles in terms of large-scale applicability. Here, we describe the preparation of fabrics and paints treated with a scaled-up novel nanostructured biohybrid material composed of very small crystalline phosphate copper(II) nanoparticles, synthesized based on a technology that employs the use of a small amount of biological agent for its formation at room temperature in aqueous media. We demonstrate the efficient inactivation of the human coronavirus 229E (HCoV-229E), the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) virus, and non-enveloped human rhinovirus 14 (HRV-14) (>99.9%) using an inexpensive, ecologically friendly coating agent. The reactive oxygen species produced during the oxidation of water or the more intensive reaction with hydrogen peroxide are believed to be the cause of the antiviral mechanism of the nanostructured material. In contrast to the release of a specific antiviral drug, this process does not consume the surface coating and does not need regeneration. A 12-month aging research that revealed no decline in antiviral activity is proof that the coating is durable in ambient circumstances. Also, the coated fabric can be reused after different washing cycles, even at moderate to high temperatures.


Assuntos
COVID-19 , Coronavirus Humano 229E , Vírus , Humanos , SARS-CoV-2 , Antivirais/farmacologia , Antivirais/química , COVID-19/prevenção & controle
4.
Food Environ Virol ; 14(3): 304-313, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-35851946

RESUMO

The experience of COVID19 pandemic has demonstrated the real concern of biological agents dispersed in the air and surfaces environments. Therefore, the need of a fast and large-scale disinfection method has arisen for prevention of contagion. COUNTERFOG® is an innovative technology developed for large-scale decontamination of air and surfaces. The objective of this study is to assess experimentally the effectiveness of COUNTERFOG® in disinfecting viral-contaminated surfaces. We also aim to measure the necessary time to disinfect said surfaces. Stainless steel surfaces were contaminated with bacteriophage φ29 and disinfected using COUNTERFOG® SDR-F05A+, which uses a sodium hypochlorite solution at different concentrations and for different exposure times. A log reduction over 6 logs of virus titer is obtained in 1 min with 1.2% sodium hypochlorite when the application is direct; while at a radial distance of 5 cm from the point of application the disinfection reaches a reduction of 5.5 logs in 8 min. In the same way, a higher dilution of the sodium hypochlorite concentration (0.7% NaOCl) requires more exposure time (16 min) to obtain the same log reduction (> 6 logs). COUNTERFOG® creates, in a short time and at a distance of 2 m from the point of application, a thin layer of disinfectant that covers the surfaces. The selection of the concentration and exposure time is critical for the efficacy of disinfection. These tests demonstrate that a concentration between 0.7- 1.2% sodium hypochlorite is enough for a fast and efficient ɸ29 phage inactivation. The fact that ɸ29 phage is more resistant to disinfection than SARS-CoV-2 sustains this disinfection procedure.


Assuntos
Bacteriófagos , COVID-19 , Desinfetantes , Descontaminação/métodos , Desinfetantes/farmacologia , Desinfecção/métodos , Humanos , SARS-CoV-2 , Hipoclorito de Sódio/farmacologia
5.
Artigo em Inglês | MEDLINE | ID: mdl-36612897

RESUMO

The COVID-19 pandemic highlighted the dangers of airborne pathogen transmission. SARS-CoV-2 is known to be transmitted through aerosols; however, little is known about the dynamics of these aerosols in real environments, the conditions, and the minimum viral load required for infection. Efficiently measuring and capturing pathogens present in the air would help to understand the infection process. Air samplers usually take several hours to obtain an air sample. In this work a fast (1-2 min) method for capturing bioaerosols into a liquid medium has been tested in hospital rooms with COVID-19 patients. This fast sampling allows detecting transient levels of aerosols in the air. SARS-CoV-2 RNA is detected in aerosols from several hospital rooms at different levels. Interestingly, there are sudden boosts of the SARS-CoV-2 load in the air, suggesting that SARS-CoV-2 could be released abundantly at certain moments. These results show that the distribution of SARS-CoV-2-containing aerosols is not homogeneous in the hospital room. This technology is a fast and effective tool for capturing airborne matter in a very short time, which allows for fast decision-making any kind of hazard in the air is detected. It is also useful for a better understanding of aerosols dynamics.


Assuntos
COVID-19 , SARS-CoV-2 , Humanos , Pandemias , RNA Viral , Aerossóis e Gotículas Respiratórios , Hospitais
6.
Sci Rep ; 11(1): 23494, 2021 12 06.
Artigo em Inglês | MEDLINE | ID: mdl-34873184

RESUMO

Foot-and-mouth disease virus (FMDV) is a picornavirus that exhibits an extremely acid sensitive capsid. This acid lability is directly related to its mechanism of uncoating triggered by acidification inside cellular endosomes. Using a collection of FMDV mutants we have systematically analyzed the relationship between acid stability and the requirement for acidic endosomes using ammonium chloride (NH4Cl), an inhibitor of endosome acidification. A FMDV mutant carrying two substitutions with opposite effects on acid-stability (VP3 A116V that reduces acid stability, and VP1 N17D that increases acid stability) displayed a rapid shift towards acid lability that resulted in increased resistance to NH4Cl as well as to concanamicyn A, a different lysosomotropic agent. This resistance could be explained by a higher ability of the mutant populations to produce NH4Cl-resistant variants, as supported by their tendency to accumulate mutations related to NH4Cl-resistance that was higher than that of the WT populations. Competition experiments also indicated that the combination of both amino acid substitutions promoted an increase of viral fitness that likely contributed to NH4Cl resistance. This study provides novel evidences supporting that the combination of mutations in a viral capsid can result in compensatory effects that lead to fitness gain, and facilitate space to an inhibitor of acid-dependent uncoating. Thus, although drug-resistant variants usually exhibit a reduction in viral fitness, our results indicate that compensatory mutations that restore this reduction in fitness can promote emergence of resistance mutants.


Assuntos
Substituição de Aminoácidos/genética , Proteínas do Capsídeo/genética , Vírus da Febre Aftosa/genética , Febre Aftosa/virologia , Animais , Linhagem Celular , Cricetinae , Endossomos/genética , Mutação/genética
7.
Pathogens ; 10(11)2021 Nov 20.
Artigo em Inglês | MEDLINE | ID: mdl-34832673

RESUMO

Neospora caninum is an apicomplexan parasite that can cause abortions and perinatal mortality in sheep. Although ovine neosporosis has been described worldwide, there is a lack of information about the relationship between N. caninum serostatus and the reproductive performance. In this study, we described the infection dynamics in a dairy sheep flock with an abortion rate up to 25% and a N. caninum seroprevalence of 32%. Abortions were recorded in 36% and 9% of seropositive and seronegative sheep, respectively. Seropositive sheep were more likely to abort twice (OR = 4.44) or three or more times (OR = 10.13) than seronegative sheep. Endogenous transplacental transmission was the main route of transmission since 86% of seropositive sheep had seropositive offspring. Within dams that had any abortion, seropositive sheep were more likely than seronegative ones to have female descendants that aborted (OR = 8.12). The slight increase in seropositivity with the age, the low percentage of animals with postnatal seroconversion or with low avidity antibodies, and the seropositivity of one flock dog, indicated that horizontal transmission might have some relevance in this flock. A control programme based on selective culling of seropositive sheep and replacement with seronegative animals was effective in reducing the abortion rate to 7.2%.

8.
Vet Parasitol ; 293: 109432, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-33915322

RESUMO

Toxoplasma gondii is a worldwide distributed parasite causing abortions and fetal malformations in small ruminants. The aim of this study was to design and validate a new immunoassay based on the use of TgSAG1-GRA8 chimeric antigen for the detection of anti-T. gondii antibodies in serum of goats. First, a time-resolved fluorescence immunoassay (TgSAG1-GRA8-TRFIA) was developed. In addition, the diagnostic performance of TgSAG1-GRA8-TRFIA was compared with an optimized enzyme-linked immunosorbent assay (TgSALUVET-ELISA) and a Western Blot (WB), both based on whole T. gondii tachyzoite antigenic extract. The TgSAG1-GRA8-TRFIA has shown a high intra- and inter-assay precision, analytical sensitivity and accuracy. The ROC analysis of this assay showed an optimal cut-off of 217.4 Units of Fluorometry for T. gondii (UFT), with 92 % of sensitivity and 90.48 % of specificity. A positive and statistically significant Spearman's correlation with TgSALUVET-ELISA was detected, and kappa value was 0.83, presenting high agreement with both methods. However, TgSAG1-GRA8 protein showed cross-reactivity with specific anti-Neospora caninum antibodies. Thus, TgSAG-1-GRA8 chimeric antigen seems not to be an ideal option for the serodiagnosis of T. gondii infection in goats unless combined with the serodiagnosis of N. caninum infection in parallel. In the light of the results obtained, a comprehensive study on the existence of cross-reactivities between T. gondii antigens used in serological tests employed in animal health and specific antibodies directed against Toxoplasmatinae parasites should be performed.


Assuntos
Anticorpos Antiprotozoários , Ensaio de Imunoadsorção Enzimática , Doenças das Cabras , Toxoplasma , Toxoplasmose Animal , Animais , Anticorpos Antiprotozoários/sangue , Antígenos de Protozoários , Coccidiose/diagnóstico , Coccidiose/veterinária , Reações Cruzadas , Ensaio de Imunoadsorção Enzimática/normas , Ensaio de Imunoadsorção Enzimática/veterinária , Doenças das Cabras/diagnóstico , Cabras , Neospora/imunologia , Estudos Soroepidemiológicos , Toxoplasma/imunologia , Toxoplasmose Animal/diagnóstico
9.
Vet Parasitol ; 276: 108994, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31778941

RESUMO

Neospora caninum is a protozoan parasite (Phylum Apicomplexa) that has been recently suggested as a relevant cause of reproductive disorders in small ruminants. The aim of the present study is to develop and validate a new serological test based on time resolved fluorescency using N. caninum GRA7 recombinant antigen (GRA7-TRFIA) for the detection of N. caninum antibodies in sheep. A total of 346 serum samples (208 from experimentally infected sheep, 117 from a dairy farm with a previous history of Neospora-associated abortion, and 21 negative sera) were used. The validation of the new assay was performed by the evaluation of assay precision, analytical sensitivity (Se), accuracy and cross reactivity. In the experimentally infected sheep, antibody kinetics was compared between GRA7-TRFIA and an in house N. caninum tachyzoite soluble extract-based ELISA (NcSALUVET ELISA) by Wilcoxon matched-pairs signed rank test. The cut-off and diagnostic Se and specificity (Sp) of GRA7-TRFIA was estimated by ROC analysis with field samples. In addition, concordance and correlation between GRA7-TRFIA and a commercial ELISA and NcSALUVET ELISA were assessed by kappa value and Spearman correlation coefficient, respectively. Overall, GRA7-TRFIA showed an adequate precision, analytical Se and accuracy to detect anti-N. caninum antibodies in ovine serum, and no cross reactivity with the closely related protozoan Toxoplasma gondii. In naturally infected sheep, 100% Se and 95.35% Sp were obtained for a cut-off point of 62.68 Units of Fluorometry for N. caninum (UFN). Moreover, GRA7-TRFIA allowed earlier detection of N. caninum infection than NcSALUVET ELISA in experimentally infected sheep.


Assuntos
Anticorpos Antiprotozoários/sangue , Antígenos de Protozoários/imunologia , Coccidiose/veterinária , Neospora/imunologia , Doenças dos Ovinos/imunologia , Animais , Coccidiose/imunologia , Reações Cruzadas , Ensaio de Imunoadsorção Enzimática/veterinária , Feminino , Imunoensaio de Fluorescência por Polarização , Fluorometria/veterinária , Imunoglobulina G/sangue , Sensibilidade e Especificidade , Ovinos , Doenças dos Ovinos/parasitologia
10.
J Clin Med ; 8(9)2019 Sep 11.
Artigo em Inglês | MEDLINE | ID: mdl-31514402

RESUMO

The objective of this study is to evaluate the risk of clinical infections by herpesviruses in patients exposed to valproic acid (VPA). We performed a case-control study nested in a primary cohort selected from the Spanish primary care population-based research database BIFAP (Base de datos para la Investigación Farmacoepidemiológica en Atención Primaria) over the period 2001-2015. The events of interest were those diseases caused by any herpesviruses known to infect humans. For each case, up to 10 controls per case matched by age, gender, and calendar date were randomly selected. A conditional logistic regression was used to compute adjusted odds ratios (OR) and their 95% confidence intervals (95% CI). Current use of VPA was associated with a trend towards a reduced risk of clinical infections by herpesviruses as compared with non-users (OR 0.84; CI 95% 0.7-1.0; p = 0.057). Among current users, a trend to a decreased risk with treatment durations longer than 90 days was also observed. The results show a trend to a reduced risk of clinical infection by herpesviruses in patients exposed to VPA. These results are consistent with those in vitro studies showing that, in cultured cells, VPA can inhibit the production of the infectious progeny of herpesviruses. This study also shows the efficient use of electronic healthcare records for clinical exploratory research studies.

11.
Viruses ; 10(2)2018 02 23.
Artigo em Inglês | MEDLINE | ID: mdl-29473907

RESUMO

Flaviviruses are relevant animal and human pathogens that include West Nile virus (WNV), Japanese encephalitis virus, dengue virus, or Zika virus, among others. Currently, no licensed therapy is available to fight flaviviral infections. Protein kinases C (PKCs) constitute a family of multifunctional lipid-dependent isoenzymes that regulate a wide variety of cellular processes (apoptosis, differentiation, proliferation, cellular transformation, motility, adhesion, etc.) being currently considered at the front line of drug development for the treatment of diverse human disorders. PKCs have also been implicated in different steps during viral replication; however, nowadays, results regarding their role in flavivirus replication are controversial. Here we demonstrate that calphostin C and chelerythrine, two broad-PKC inhibitors that target conventional, novel and atypical PKCs, significantly inhibit WNV multiplication in cell culture without affecting cell viability. A reduction of viral yields was observed in treated cells when compared with mock-treated cells. Likewise, immunofluorescence detection of viral enveloped E protein was reduced in treated cells, as was the amount of viral RNA released to the supernatant, mainly in those treated with chelerythrine. On the other hand, two PKC inhibitors specific for conventional and novel isoforms (staurosporine and enzastaurine) did not show any significant effect in WNV multiplication. These results suggested that PKCs, more probably atypical PKCs, are likely involved in WNV multiplication, although both broad-spectrum tested drugs seem to act through different mechanisms, and point to them as potential antiviral candidates for WNV, as well as for other related flaviviruses.


Assuntos
Antivirais/farmacologia , Inibidores Enzimáticos/farmacologia , Proteína Quinase C/antagonistas & inibidores , Replicação Viral/efeitos dos fármacos , Febre do Nilo Ocidental/metabolismo , Febre do Nilo Ocidental/virologia , Vírus do Nilo Ocidental/efeitos dos fármacos , Vírus do Nilo Ocidental/fisiologia , Animais , Chlorocebus aethiops , Humanos , Células Vero
12.
Emerg Microbes Infect ; 6(9): e81, 2017 Sep 20.
Artigo em Inglês | MEDLINE | ID: mdl-28928416

RESUMO

Flaviviruses are RNA viruses that constitute a worrisome threat to global human and animal health. Zika virus (ZIKV), which was initially reported to cause a mild disease, recently spread in the Americas, infecting millions of people. During this recent epidemic, ZIKV infection has been linked to serious neurological diseases and birth defects, specifically Guillain-Barrè syndrome (GBS) and microcephaly. Because information about ZIKV immunity remains scarce, we assessed the humoral response of immunocompetent mice to infection with three viral strains of diverse geographical origin (Africa, Asia and America). No infected animals showed any sign of disease or died after infection. However, specific neutralizing antibodies were elicited in all infected mice. Considering the rapid expansion of ZIKV throughout the American continent and its co-circulation with other medically relevant flaviviruses, such as West Nile virus (WNV), the induction of protective immunity between ZIKV and WNV was analyzed. Remarkably, protection after challenge with WNV was observed in mice previously infected with ZIKV, as survival rates were significantly higher than in control mice. Moreover, previous ZIKV infection enhanced the humoral immune response against WNV. These findings may be relevant in geographical areas where both ZIKV and WNV co-circulate, as well as for the future development of broad-spectrum flavivirus vaccines.


Assuntos
Anticorpos Neutralizantes/imunologia , Anticorpos Antivirais/imunologia , Febre do Nilo Ocidental/imunologia , Vírus do Nilo Ocidental/imunologia , Infecção por Zika virus/imunologia , Zika virus/imunologia , África/epidemiologia , América/epidemiologia , Animais , Anticorpos Neutralizantes/biossíntese , Anticorpos Neutralizantes/sangue , Anticorpos Antivirais/biossíntese , Anticorpos Antivirais/sangue , Ásia/epidemiologia , Imunidade Humoral , Imunocompetência , Camundongos , Febre do Nilo Ocidental/virologia , Vírus do Nilo Ocidental/isolamento & purificação , Zika virus/genética , Infecção por Zika virus/epidemiologia
13.
Front Microbiol ; 8: 1314, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28744282

RESUMO

The Flavivirus genus contains important pathogens, such as West Nile virus (WNV), Zika virus (ZIKV), and Dengue virus (DENV), which are enveloped plus-strand RNA viruses transmitted by mosquitoes and constitute a worrisome threat to global human and animal health. Currently no licensed drugs against them are available, being, thus, still necessary the search for effective antiviral molecules. In this line, a novel antiviral approach (economical, simple to use, and environmental friendly) is the use of natural compounds. Consequently, we have tested the antiviral potential of different polyphenols present in plants and natural products, such as wine and tea, against WNV, ZIKV, and DENV. So that, we assayed the effect of a panel of structurally related polyphenols [delphinidin (D), cyanidin (Cy), catechin (C), epicatechin (EC), epigallocatechin (EGC), and epigallocatechin gallate (EGCG)] on WNV infection, and found that D and EGCG inhibited more effectively the virus production. Further analysis with both compounds indicated that they mainly affected the attachment and entry steps of the virus life cycle. Moreover, D and EGCG showed a direct effect on WNV particles exerting a virucidal effect. We showed a similar inhibition of viral production of these compounds on WNV variants that differed on acidic pH requirements for viral fusion, indicating that their antiviral activity against WNV is produced by a virucidal effect rather than by an inhibition of pH-dependent viral fusion. Both polyphenols also reduced the infectivity of ZIKV and DENV. Therefore, D and EGCG impair the infectivity in cell culture of these three medically relevant flaviviruses.

14.
Vet Microbiol ; 203: 275-279, 2017 May.
Artigo em Inglês | MEDLINE | ID: mdl-28619156

RESUMO

Foot-and-mouth disease virus (FMDV) is the etiological agent of a highly contagious disease that affects important livestock species. Vaccines based on inactivated FMDV virions provide a useful tool for the control of this pathogen. However, long term storage at 4°C (the temperature for vaccine storage) or ruptures of the cold chain, provoke the dissociation of virions, reducing the immunogenicity of the vaccine. An FMDV mutant carrying amino acid replacements VP1 N17D and VP2 H145Y isolated previously rendered virions with increased resistance to dissociation at 4°C. We have evaluated the immunogenicity in swine (a natural FMDV host) of a chemically inactivated vaccine based on this mutant. The presence of these amino acid substitutions did not compromise the immunological potential, including its ability to elicit neutralizing antibodies. These results support the feasibility of this kind of mutants with increased capsid stability as suitable viruses for producing improved FMDV vaccines.


Assuntos
Anticorpos Antivirais/imunologia , Proteínas do Capsídeo/imunologia , Vírus da Febre Aftosa/imunologia , Febre Aftosa/prevenção & controle , Doenças dos Suínos/prevenção & controle , Vacinas Virais/imunologia , Substituição de Aminoácidos , Animais , Anticorpos Neutralizantes , Proteínas do Capsídeo/genética , Febre Aftosa/virologia , Vírus da Febre Aftosa/genética , Modelos Moleculares , Mutação , Suínos , Doenças dos Suínos/virologia , Vacinas de Produtos Inativados/imunologia , Vírion
15.
Prog Lipid Res ; 64: 123-137, 2016 10.
Artigo em Inglês | MEDLINE | ID: mdl-27702593

RESUMO

Flaviviruses are emerging arthropod-borne pathogens that cause life-threatening diseases such as yellow fever, dengue, West Nile encephalitis, tick-borne encephalitis, Kyasanur Forest disease, tick-borne encephalitis, or Zika disease. This viral genus groups >50 viral species of small enveloped plus strand RNA virus that are phylogenetically closely related to hepatitis C virus. Importantly, the flavivirus life cycle is intimately associated to host cell lipids. Along this line, flaviviruses rearrange intracellular membranes from the endoplasmic-reticulum of the infected cells to develop adequate platforms for viral replication and particle biogenesis. Moreover, flaviviruses dramatically orchestrate a profound reorganization of the host cell lipid metabolism to create a favorable environment for viral multiplication. Consistently, recent work has shown the importance of specific lipid classes in flavivirus infections. For instances, fatty acid synthesis is linked to viral replication, phosphatidylserine and phosphatidylethanolamine are involved on the entry of flaviviruses, sphingolipids (ceramide and sphingomyelin) play a key role on virus assembly and pathogenesis, and cholesterol is essential for innate immunity evasion in flavivirus-infected cells. Here, we revise the current knowledge on the interactions of the flaviviruses with the cellular lipid metabolism to identify potential targets for future antiviral development aimed to combat these relevant health-threatening pathogens.


Assuntos
Flavivirus/metabolismo , Metabolismo dos Lipídeos/fisiologia , Animais , Vírus da Dengue/metabolismo , Vírus da Dengue/patogenicidade , Encefalite/metabolismo , Encefalite/patologia , Encefalite/virologia , Flavivirus/patogenicidade , Infecções por Flavivirus/metabolismo , Infecções por Flavivirus/patologia , Infecções por Flavivirus/virologia , Humanos , Fosfatidiletanolaminas/metabolismo , Fosfatidilserinas/metabolismo , Esfingolipídeos/metabolismo , Vírus do Nilo Ocidental/metabolismo , Vírus do Nilo Ocidental/patogenicidade , Zika virus/metabolismo , Zika virus/patogenicidade
17.
J Virol ; 90(21): 9725-9732, 2016 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-27535044

RESUMO

Equine rhinitis A virus (ERAV) is a picornavirus associated with respiratory disease in horses and is genetically closely related to foot-and-mouth disease virus (FMDV), the prototype aphthovirus. ERAV has recently gained interest as an FMDV alternative for the study of aphthovirus biology, including cell entry and uncoating or antiviral testing. As described for FMDV, current data support that acidic pH inside cellular endosomes triggers ERAV uncoating. In order to provide further insights into aphthovirus uncoating mechanism, we have isolated a panel of ERAV mutants with altered acid sensitivity and that differed on their degree of sensitivity to the inhibition of endosome acidification. These results provide functional evidence of the involvement of acidic pH on ERAV uncoating within endosomes. Remarkably, all amino acid substitutions found in acid-labile or acid-resistant ERAVs were located in the capsid protein VP3, indicating that this protein plays a pivotal role for the control of pH stability of the ERAV capsid. Moreover, all amino acid substitutions mapped at the intraprotomer interface between VP3 and VP2 or between VP3 and the N terminus of VP1. These results expand our knowledge on the regions that regulate the acid stability of aphthovirus capsid and should be taken into account when using ERAV as a surrogate of FMDV. IMPORTANCE: The viral capsid constitutes a sort of dynamic nanomachine that protects the viral genome against environmental assaults while accomplishing important functions such as receptor attachment for viral entry or genome release. We have explored the molecular determinants of aphthovirus capsid stability by isolating and characterizing a panel of equine rhinitis A virus mutants that differed on their acid sensitivity. All the mutations were located within a specific region of the capsid, the intraprotomer interface among capsid proteins, thus providing new insights into the regions that control the acid stability of aphthovirus capsid. These findings could positively contribute to the development of antiviral approaches targeting aphthovirus uncoating or the refinement of vaccine strategies based on capsid stabilization.


Assuntos
Ácidos/metabolismo , Aphthovirus/genética , Proteínas do Capsídeo/genética , Cavalos/virologia , Substituição de Aminoácidos/genética , Animais , Antivirais/farmacologia , Aphthovirus/efeitos dos fármacos , Capsídeo/efeitos dos fármacos , Endossomos/virologia , Vírus da Febre Aftosa/efeitos dos fármacos , Genoma Viral/genética , Concentração de Íons de Hidrogênio , Mutação/genética , Infecções por Picornaviridae/tratamento farmacológico , Infecções por Picornaviridae/virologia , Internalização do Vírus/efeitos dos fármacos
18.
Front Microbiol ; 7: 612, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27199941

RESUMO

Swine vesicular disease virus (SVDV) is a porcine pathogen and a member of the species Enterovirus B within the Picornaviridae family. Brefeldin A (BFA) is an inhibitor of guanine nucleotide exchange factors of Arf proteins that induces Golgi complex disassembly and alters the cellular secretory pathway. Since BFA has been shown to inhibit the RNA replication of different enteroviruses, including SVDV, we have analyzed the effect of BFA and of golgicide A (GCA), another Golgi disrupting drug, on SVDV multiplication. BFA and GCA similarly inhibited SVDV production. To investigate the molecular basis of the antiviral effect of BFA, SVDV mutants with increased resistance to BFA were isolated. A single amino acid substitution, Q65H, in the non-structural protein 2C was found to be responsible for increased resistance to BFA. These results provide new insight into the relationship of enteroviruses with the components of the secretory pathway and on the role of SVDV 2C protein in this process.

19.
Front Microbiol ; 7: 496, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27148186

RESUMO

Since the beginning of this century, humanity has been facing a new emerging, or re-emerging, virus threat almost every year: West Nile, Influenza A, avian flu, dengue, Chikungunya, SARS, MERS, Ebola, and now Zika, the latest newcomer. Zika virus (ZIKV), a flavivirus transmitted by Aedes mosquitoes, was identified in 1947 in a sentinel monkey in Uganda, and later on in humans in Nigeria. The virus was mainly confined to the African continent until it was detected in south-east Asia the 1980's, then in the Micronesia in 2007 and, more recently in the Americas in 2014, where it has displayed an explosive spread, as advised by the World Health Organization, which resulted in the infection of hundreds of thousands of people. ZIKV infection was characterized by causing a mild disease presented with fever, headache, rash, arthralgia, and conjunctivitis, with exceptional reports of an association with Guillain-Barre syndrome (GBS) and microcephaly. However, since the end of 2015, an increase in the number of GBS associated cases and an astonishing number of microcephaly in fetus and new-borns in Brazil have been related to ZIKV infection, raising serious worldwide public health concerns. Clarifying such worrisome relationships is, thus, a current unavoidable goal. Here, we extensively review what is currently known about ZIKV, from molecular biology, transmission routes, ecology, and epidemiology, to clinical manifestations, pathogenesis, diagnosis, prophylaxis, and public health.

20.
Genome Announc ; 4(2)2016 Mar 03.
Artigo em Inglês | MEDLINE | ID: mdl-26941157

RESUMO

Swine vesicular disease virus (SVDV) is a porcine pathogen and a member of the Enterovirus genus within the Picornaviridae family. The SVDV genome is composed of a single-stranded RNA molecule of positive polarity. Here, we report the first complete sequence of the coding region of a Spanish SVDV isolate (SPA/1/'93).

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