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1.
Virologie (Montrouge) ; 26(5): 355-373, 2022 09 01.
Artículo en Francés | MEDLINE | ID: mdl-36413121

RESUMEN

Foot-and-mouth disease (FMD) is one of the most contagious viral animal diseases. It is an old disease which still poses a permanent threat of re-emergence for free zones. Foot-and-Mouth Disease Virus (FMDV), a Picornavirus belonging to genus Aphthovirus affects domestic and wild artiodactyls. FMD has a considerable socio-economic impact on agricultural production and trade in endemic regions, but also when incursions occur into FMD free areas, as in Europe in 2001. FMDV is historically one of the most studied viruses. Due to its high genetic and antigenic variability, the absence of cross-immunity between its seven serotypes, its ability to survive in the environment, its high contagiousness, its wide range of hosts and its particular biology, FMDV remains of major interest in animal health and the subject of many research projects. This review presents different aspects of FMDV infection, ranging from basic biology to diagnosis, surveillance and control.


La fièvre aphteuse (FA) est l'une des maladies virales animales les plus contagieuses. Bien que très ancienne, la FA reste toujours d'actualité et représente une menace permanente de réémergence pour les pays indemnes. Le virus de la FA ou FMDV (pour foot-and-mouth disease virus), de la famille Picornaviridae, genre Aphthovirus, affecte les artiodactyles domestiques comme sauvages (principalement bovins, ovins, caprins, porcins, camélidés et cervidés). La fièvre aphteuse a un impact socio-économique considérable sur la production et le commerce agricoles en zone d'enzootie mais également en cas d'incursion dans une zone précédemment indemne comme ce fut le cas en 2001 en Europe. Le virus de la FA est historiquement l'un des virus les plus étudiés. Par sa grande variabilité génétique et antigénique, l'absence d'immunité croisée entre ses sept sérotypes, sa capacité de survie dans l'environnement, sa grande contagiosité, son large spectre d'hôtes ainsi que sa biologie particulière, ce virus reste d'intérêt majeur en santé animale et l'objet de nombreux travaux de recherche. Cette revue vise à présenter différents aspects de l'infection par le virus de la fièvre aphteuse et ses problématiques actuelles, de la biologie fondamentale au diagnostic en passant par la surveillance et les moyens de lutte.


Asunto(s)
Artiodáctilos , Virus de la Fiebre Aftosa , Fiebre Aftosa , Animales , Virus de la Fiebre Aftosa/genética , Fiebre Aftosa/diagnóstico , Fiebre Aftosa/epidemiología , Fiebre Aftosa/prevención & control , Serogrupo , Europa (Continente)/epidemiología
2.
PLoS Pathog ; 11(3): e1004733, 2015 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-25799064

RESUMEN

The genus Enterovirus of the family Picornaviridae contains many important human pathogens (e.g., poliovirus, coxsackievirus, rhinovirus, and enterovirus 71) for which no antiviral drugs are available. The viral RNA-dependent RNA polymerase is an attractive target for antiviral therapy. Nucleoside-based inhibitors have broad-spectrum activity but often exhibit off-target effects. Most non-nucleoside inhibitors (NNIs) target surface cavities, which are structurally more flexible than the nucleotide-binding pocket, and hence have a more narrow spectrum of activity and are more prone to resistance development. Here, we report a novel NNI, GPC-N114 (2,2'-[(4-chloro-1,2-phenylene)bis(oxy)]bis(5-nitro-benzonitrile)) with broad-spectrum activity against enteroviruses and cardioviruses (another genus in the picornavirus family). Surprisingly, coxsackievirus B3 (CVB3) and poliovirus displayed a high genetic barrier to resistance against GPC-N114. By contrast, EMCV, a cardiovirus, rapidly acquired resistance due to mutations in 3Dpol. In vitro polymerase activity assays showed that GPC-N114 i) inhibited the elongation activity of recombinant CVB3 and EMCV 3Dpol, (ii) had reduced activity against EMCV 3Dpol with the resistance mutations, and (iii) was most efficient in inhibiting 3Dpol when added before the RNA template-primer duplex. Elucidation of a crystal structure of the inhibitor bound to CVB3 3Dpol confirmed the RNA-binding channel as the target for GPC-N114. Docking studies of the compound into the crystal structures of the compound-resistant EMCV 3Dpol mutants suggested that the resistant phenotype is due to subtle changes that interfere with the binding of GPC-N114 but not of the RNA template-primer. In conclusion, this study presents the first NNI that targets the RNA template channel of the picornavirus polymerase and identifies a new pocket that can be used for the design of broad-spectrum inhibitors. Moreover, this study provides important new insight into the plasticity of picornavirus polymerases at the template binding site.


Asunto(s)
Antivirales/química , Cardiovirus/enzimología , Enterovirus Humano B/enzimología , Poliovirus/enzimología , ARN Polimerasa Dependiente del ARN/antagonistas & inhibidores , Proteínas Virales/antagonistas & inhibidores , Animales , Sitios de Unión , Chlorocebus aethiops , Células HeLa , Humanos , ARN Polimerasa Dependiente del ARN/química , ARN Polimerasa Dependiente del ARN/metabolismo , Proteínas Virales/química , Proteínas Virales/metabolismo
3.
Toxicol Pathol ; 43(5): 715-29, 2015 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-25694087

RESUMEN

Exposure to the mycotoxin ochratoxin A (OTA) causes nephropathy in domestic animals and rodents and renal tumors in rodents and poultry. Humans are exposed to OTA by consuming foods made with contaminated cereal grains and other commodities. Management of human health risks due to OTA exposure depends, in part, on establishing a mode of action (MOA) for OTA carcinogenesis. To further investigate OTA's MOA, p53 heterozygous (p53+/-) and p53 homozygous (p53+/+) mice were exposed to OTA in diet for 26 weeks. The former are susceptible to tumorigenesis upon chronic exposure to genotoxic carcinogens. OTA-induced renal damage but no tumors were observed in either strain, indicating that p53 heterozygosity conferred little additional sensitivity to OTA. Renal changes included dose-dependent increases in cellular proliferation, apoptosis, karyomegaly, and tubular degeneration in proximal tubules, which were consistent with ochratoxicosis. The lowest observed effect level for renal changes in p53+/- and p53+/+ mice was 200 µg OTA/kg bw/day. Based on the lack of tumors and the severity of renal and body weight changes at a maximum tolerated dose, the results were interpreted as suggestive of a primarily nongenotoxic (epigenetic) MOA for OTA carcinogenesis in this mouse model.


Asunto(s)
Ocratoxinas/toxicidad , Proteína p53 Supresora de Tumor/genética , Animales , Ingestión de Alimentos/efectos de los fármacos , Inmunohistoquímica , Riñón/efectos de los fármacos , Leucocitos/efectos de los fármacos , Hígado/efectos de los fármacos , Masculino , Ratones , Ratones Noqueados , Tamaño de los Órganos/efectos de los fármacos , Pruebas de Toxicidad Crónica
4.
Biochem Biophys Res Commun ; 455(3-4): 378-81, 2014 Dec 12.
Artículo en Inglés | MEDLINE | ID: mdl-25446115

RESUMEN

The stamping-out policy for the control of foot-and-mouth disease virus (FMDV) in countries that are free from FMD without vaccination has a dramatic socio-economic impact, huge animal welfare issues and may result in the loss of farm animal genetic resources. As an alternative to pre-emptive culling or emergency vaccination we further explore the possibility to use antiviral drugs in the event of an FMD outbreak. In the present study, we tested the in vitro cytotoxicity and anti-FMDV activity of 1,2,4,5-tetrahydro-[1,4]thiazepino[4,5-a]benzimidazole. The molecule was shown to inhibit the replication of reference strains of the Eurasian FMDV serotypes O, A, C and Asia but not the FMDV serotypes from the South African Territories (SAT) neither a related picornavirus, i.e. swine vesicular disease virus. The molecule can be added until 2h post inoculation in a 'single replication cycle experiment' without losing its antiviral activity. The genetic characterization of progressively selected resistant FMD viruses shows that the molecule presumably interacts with the non-structural 2C protein of FMDV. Further studies are required on the use of this molecule in vivo.


Asunto(s)
Bencimidazoles/química , Virus de la Fiebre Aftosa/fisiología , Tiazepinas/química , Replicación Viral , Animales , Antivirales/química , Línea Celular , Supervivencia Celular , Fiebre Aftosa/virología , Virus de la Fiebre Aftosa/genética , Mutación , Análisis de Secuencia de ADN , Serogrupo , Porcinos
5.
Environ Toxicol ; 28(4): 215-28, 2013 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-21544923

RESUMEN

Brominated diphenyl ethers (BDEs) are persistent environmental contaminants found in human blood, tissues, and milk. To assess the impact of the commercial BDE mixture DE-71 on the developing immune system in relation to hepatic and thyroid changes, adult (F0) rats were exposed to DE-71 by gavage at doses of 0, 0.5, 5, or 25 mg/kg body weight (bw)/d for 21 weeks. F0 rats were bred and exposure continued through gestation, lactation and postweaning. F1 pups were weaned and exposed to DE-71 by gavage from postnatal day (PND) 22 to 42. On PND 42, half of the F1 rats were assessed for toxicologic changes. The remaining F1 rats were challenged with the T-dependent antigen keyhole limpet hemocyanin (KLH) and immune function was assessed on PND 56. Dose-dependent increases in total BDE concentrations were detected in the liver and adipose of all F0 and F1 rats. In F0 rats, increased liver weight, hepatocellular hypertrophy, and decreased serum thyroxine (T4) were characteristic of DE-71 exposure. In F1 rats perinatal DE-71 exposure caused a nondose-dependent increase in body weight and dose-dependent increases in liver weight and hepatocellular hypertrophy. Serum T3 and T4 levels were decreased. In spleen from DE-71 exposed rats the area occupied by B cells declined while the area occupied by T cells increased; however, cellular and humoral immune responses to KLH challenge were not altered. Thus hepatic and thyroid changes in rats exposed perinatally to DE-71 were associated with altered splenic lymphocyte populations, an effect which has been linked to hypothyroidism.


Asunto(s)
Contaminantes Ambientales/toxicidad , Éteres Difenilos Halogenados/toxicidad , Sistema Inmunológico/efectos de los fármacos , Efectos Tardíos de la Exposición Prenatal , Adulto , Animales , Peso Corporal/efectos de los fármacos , Contaminantes Ambientales/análisis , Contaminantes Ambientales/inmunología , Femenino , Éteres Difenilos Halogenados/análisis , Éteres Difenilos Halogenados/inmunología , Humanos , Sistema Inmunológico/embriología , Sistema Inmunológico/crecimiento & desarrollo , Lactancia , Hígado/efectos de los fármacos , Hígado/metabolismo , Hígado/patología , Masculino , Exposición Materna/efectos adversos , Leche/química , Tamaño de los Órganos/efectos de los fármacos , Exposición Paterna/efectos adversos , Embarazo , Ratas , Ratas Sprague-Dawley , Reproducción/efectos de los fármacos , Bazo/efectos de los fármacos , Bazo/patología , Hormonas Tiroideas/sangre , Factores de Tiempo , Distribución Tisular , Destete
6.
Viruses ; 15(4)2023 04 14.
Artículo en Inglés | MEDLINE | ID: mdl-37112947

RESUMEN

The Horn of Africa is a large area of arid and semi-arid land, holding about 10% of the global and 40% of the entire African livestock population. The region's livestock production system is mainly extensive and pastoralist. It faces countless problems, such as a shortage of pastures and watering points, poor access to veterinary services, and multiple endemic diseases like foot-and-mouth disease (FMD). Foot-and-mouth disease is one of the most economically important livestock diseases worldwide and is endemic in most developing countries. Within Africa, five of the seven serotypes of the FMD virus (FMDV) are described, but serotype C is not circulating anymore, a burden unseen anywhere in the world. The enormous genetic diversity of FMDV is favored by an error-prone RNA-dependent RNA polymerase, intra-typic and inter-typic recombination, as well as the quasi-species nature of the virus. This paper describes the epidemiological dynamics of foot-and-mouth disease in the Horn of Africa with regard to the serotypes and topotypes distribution of FMDV, the livestock production systems practiced, animal movement, the role of wildlife, and the epidemiological complexity of FMD. Within this review, outbreak investigation data and serological studies confirm the endemicity of the disease in the Horn of Africa. Multiple topotypes of FMDV are described in the literature as circulating in the region, with further evolution of virus diversity predicted. A large susceptible livestock population and the presence of wild ungulates are described as complicating the epidemiology of the disease. Further, the husbandry practices and legal and illegal trading of livestock and their products, coupled with poor biosecurity practices, are also reported to impact the spread of FMDV within and between countries in the region. The porosity of borders for pastoralist herders fuels the unregulated transboundary livestock trade. There are no systematic control strategies in the region except for sporadic vaccination with locally produced vaccines, while literature indicates that effective control measures should also consider virus diversity, livestock movements/biosecurity, transboundary trade, and the reduction of contact with wild, susceptible ungulates.


Asunto(s)
Virus de la Fiebre Aftosa , Fiebre Aftosa , Animales , Virus de la Fiebre Aftosa/genética , Animales Salvajes , África , Serogrupo , Ganado , Brotes de Enfermedades/veterinaria
7.
Front Vet Sci ; 10: 1271434, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-38076547

RESUMEN

The Nagoya Protocol is an international agreement adopted in 2010 (and entered into force in 2014) which governs access to genetic resources and the fair and equitable sharing of benefits from their utilisation. The agreement aims to prevent misappropriation of genetic resources and, through benefit sharing, create incentives for the conservation and sustainable use of biological diversity. While the equitable sharing of the benefits arising from the utilisation of genetic resources is a widely accepted concept, the way in which the provisions of the Nagoya Protocol are currently being implemented through national access and benefit-sharing legislation places significant logistical challenges on the control of transboundary livestock diseases such as foot-and-mouth disease (FMD). Delays to access FMD virus isolates from the field disrupt the production of new FMD vaccines and other tailored tools for research, surveillance and outbreak control. These concerns were raised within the FMD Reference Laboratory Network and were explored at a recent multistakeholder meeting hosted by the European Commission for the Control of FMD. The aim of this paper is to promote wider awareness of the Nagoya Protocol, and to highlight its impacts on the regular exchange and utilisation of biological materials collected from clinical cases which underpin FMD research activities, and work to develop new epidemiologically relevant vaccines and other diagnostic tools to control the disease.

8.
J Gen Virol ; 93(Pt 7): 1548-1555, 2012 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-22492916

RESUMEN

Porcine circovirus 2 (PCV2) is the causative agent of porcine circovirus-associated diseases in pigs. Previously, it was demonstrated that mAbs 16G12, 38C1, 63H3 and 94H8 directed against the PCV2 capsid protein recognize PCV2 strains Stoon-1010 (PCV2a), 48285 (PCV2b), 1121 (PCV2a), 1147 (PCV2b) and II9F (PCV2b), but only neutralize Stoon-1010 and 48285. This points to the existence of two distinct PCV2 neutralization phenotypes: phenotype α (mAb recognition with neutralization; Stoon-1010 and 48285) and phenotype ß (mAb recognition without neutralization; 1121, 1147 and II9F). In the present study, amino acids that are important in determining the neutralization phenotype were identified in the capsid. Mutation of T at position 190 to A in strain 48285 (phenotype α) resulted in a capsid resembling that of strain 1147 (phenotype ß) and caused a loss of neutralization (switch from α to ß). Mutations of P at position 151 to T and A at position 190 to T in strain II9F (phenotype ß) resulted in a capsid resembling that of strain 48285 (phenotype α) and gave a gain of neutralization (switch from ß to α). Mutations of T at position 131 to P and of E at position 191 to R in Stoon-1010 (phenotype α) changed the capsid into that of 1121 (phenotype ß) and reduced neutralization (switch from α to ß). This study demonstrated that single amino acid changes in the capsid result in a phenotypic switch from α to ß or ß to α.


Asunto(s)
Anticuerpos Neutralizantes/inmunología , Anticuerpos Antivirales/inmunología , Proteínas de la Cápside/genética , Proteínas de la Cápside/inmunología , Circovirus/genética , Circovirus/inmunología , Mutación Missense , Sustitución de Aminoácidos , Animales , Anticuerpos Monoclonales/inmunología , Pruebas de Neutralización
9.
Viruses ; 14(5)2022 05 17.
Artículo en Inglés | MEDLINE | ID: mdl-35632817

RESUMEN

Burundi is a small, densely populated country in the African Great Lakes region. In March 2016, several hundreds of cattle were reported with vesicular lesions, suggesting foot-and-mouth disease (FMD). Epithelial samples, saliva, and blood were collected in six of the affected provinces spread over the country. The overall seroprevalence of FMD virus (FMDV) in the affected herds, as determined by antibodies against FMDV non-structural proteins, was estimated at 87%. Antibodies against FMDV serotypes O (52%), A (44%), C (19%), SAT1 (36%), SAT2 (58%), and SAT3 (23%) were detected across the provinces. FMDV genome was detected in samples from five of the six provinces using rRT-PCR. FMDV was isolated from samples from three provinces: in Cibitoke province, serotypes A and SAT2 were isolated, while in Mwaro and Rutana provinces, only serotype SAT2 was isolated. In Bururi and Cankuzo provinces, the serological profile suggested a recent incursion with serotype SAT2, while in Bubanza province, the serological profile suggested past incursions with serotype O and possibly serotype SAT1. The phylogenetic assessments showed the presence of topotypes A/Africa/G-I and SAT2/IV, similarly to previously characterized virus strains from other countries in the region, suggesting a transboundary origin and necessitating a regional approach for vaccination and control of FMD.


Asunto(s)
Enfermedades de los Bovinos , Virus de la Fiebre Aftosa , Fiebre Aftosa , África Oriental/epidemiología , Animales , Burundi/epidemiología , Bovinos , Enfermedades de los Bovinos/epidemiología , Brotes de Enfermedades/veterinaria , Fiebre Aftosa/epidemiología , Filogenia , Estudios Seroepidemiológicos , Serogrupo
10.
Transbound Emerg Dis ; 69(5): e2230-e2239, 2022 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-35435315

RESUMEN

Foot-and-mouth disease (FMD) affects the livestock industry and socioeconomic sustainability of many African countries. The success of FMD control programs in Africa depends largely on understanding the dynamics of FMD virus (FMDV) spread. In light of the recent outbreaks of FMD that affected the North-Western African countries in 2018 and 2019, we investigated the evolutionary phylodynamics of the causative serotype O viral strains all belonging to the East-Africa 3 topotype (O/EA-3). We analyzed a total of 489 sequences encoding the FMDV VP1 genome region generated from samples collected from 25 African and Western Asian countries between 1974 and 2019. Using Bayesian evolutionary models on genomic and epidemiological data, we inferred the routes of introduction and migration of the FMDV O/EA-3 topotype at the inter-regional scale. We inferred a mean substitution rate of 6.64 × 10-3  nt/site/year and we predicted that the most recent common ancestor for our panel of samples circulated between February 1967 and November 1973 in Yemen, likely reflecting the epidemiological situation in under sampled cattle-exporting East African countries. Our study also reinforces the role previously described of Sudan and South Sudan as a frequent source of FMDVs spread. In particular, we identified two transboundary routes of O/EA-3 diffusion: the first from Sudan to North-East Africa, and from the latter into Israel and Palestine AT; a second from Sudan to Nigeria, Cameroon, and from there to further into West and North-West Africa. This study highlights the necessity to reinforce surveillance at an inter-regional scale in Africa and Western Asia, in particular along the identified migration routes for the implementation of efficient control measures in the fight against FMD.


Asunto(s)
Virus de la Fiebre Aftosa , Fiebre Aftosa , Animales , Teorema de Bayes , Bovinos , Brotes de Enfermedades/veterinaria , Fiebre Aftosa/epidemiología , Virus de la Fiebre Aftosa/genética , Nigeria/epidemiología , Filogenia , Serogrupo
11.
BMC Vet Res ; 7: 64, 2011 Oct 21.
Artículo en Inglés | MEDLINE | ID: mdl-22018436

RESUMEN

BACKGROUND: Porcine circovirus type 1 (PCV1) has been described as a non-cytopathic contaminant of the PK-15 cell line. Several experimental infections with PCV1 failed to reproduce disease in pigs. Therefore, PCV1 is generally accepted as non-pathogenic to pigs. To our knowledge, nothing is known about the outcome of PCV1 infections in porcine foetuses. This was examined in the present study. RESULTS: Nine foetuses from three sows were inoculated at 55 days of gestation: three with 10(4.3) TCID(50) of the PCV1 cell culture strain ATCC-CCL33, three with 10(4.3) TCID(50) of the PCV1 field strain 3384 and three with cell culture medium (mock-inoculated). At 21 days post-inoculation, all 6 PCV1-inoculated and all 3 mock-inoculated foetuses had a normal external appearance. Microscopic lesions characterized by severe haemorrhages were observed in the lungs of two foetuses inoculated with CCL33. High PCV1 titres (up to 10(4.7) TCID(50)/g tissue) were found in the lungs of the CCL33-inoculated foetuses. All other organs of the CCL33-inoculated foetuses and all the organs of the 3384-inoculated foetuses were negative (< 10(1.7) TCID(50)/g tissue) by virus titration. PCV1-positive cells (up to 121 cells/10 mm(2) in CCL33-inoculated foetuses and up to 13 cells/10 mm(2) in 3384-inoculated foetuses) were found in the heart, lungs, spleen, liver, thymus and tonsils. PCR and DNA sequencing of Rep recovered CCL33 or 3384 sequences from CCL33- or 3384-inoculated foetuses, respectively. CONCLUSIONS: From this study, it can be concluded that cell culture PCV1 can replicate efficiently and produce pathology in the lungs of porcine foetuses inoculated at 55 days of foetal life.


Asunto(s)
Infecciones por Circoviridae/veterinaria , Circovirus , Enfermedades Fetales/veterinaria , Enfermedades de los Porcinos/virología , Animales , Infecciones por Circoviridae/virología , Circovirus/genética , Femenino , Enfermedades Fetales/virología , Técnica del Anticuerpo Fluorescente/veterinaria , Genes Virales/genética , Pulmón/virología , Embarazo , Porcinos/virología , Enfermedades de los Porcinos/embriología
12.
Microbiol Resour Announc ; 10(14)2021 Apr 08.
Artículo en Inglés | MEDLINE | ID: mdl-33833026

RESUMEN

Bluetongue is one of the major diseases of ruminants listed by the World Organisation for Animal Health. Bluetongue virus serotype 8 (BTV-8) has been considered enzootic in France since 2018. Here, we report the nearly complete genome sequences of two BTV-8 isolates from the 2020 outbreak in the Grand Duchy of Luxembourg.

13.
Cell Chem Biol ; 28(2): 202-212.e6, 2021 02 18.
Artículo en Inglés | MEDLINE | ID: mdl-33450181

RESUMEN

MicroRNAs (miRNAs) act as cellular signal transducers through repression of protein translation. Elucidating targets using bioinformatics and traditional quantitation methods is often insufficient to uncover global miRNA function. Herein, alteration of protein function caused by miRNA-185 (miR-185), an immunometabolic miRNA, was determined using activity-based protein profiling, transcriptomics, and lipidomics. Fluorophosphonate-based activity-based protein profiling of miR-185-induced changes to human liver cells revealed that exclusively metabolic serine hydrolase enzymes were regulated in activity, some with roles in lipid and endocannabinoid metabolism. Lipidomic analysis linked enzymatic changes to levels of cellular lipid species, such as components of very-low-density lipoprotein particles. Additionally, inhibition of one miR-185 target, monoglyceride lipase, led to decreased hepatitis C virus levels in an infectious model. Overall, the approaches used here were able to identify key functional changes in serine hydrolases caused by miR-185 that are targetable pharmacologically, such that a small molecule inhibitor can recapitulate the miRNA phenotype.


Asunto(s)
Perfilación de la Expresión Génica , MicroARNs/genética , Transcriptoma , Línea Celular , Hepatocitos/metabolismo , Humanos , Lipidómica , Proteómica
14.
Sci Rep ; 11(1): 19907, 2021 10 07.
Artículo en Inglés | MEDLINE | ID: mdl-34620924

RESUMEN

The number of reforestation projects worldwide is increasing. In many cases funding is obtained through the claimed carbon capture of the trees, presented as immediate and durable, whereas reforested plots need time and maintenance to realise their carbon capture potential. Further, claims usually overlook the environmental costs of natural or anthropogenic disturbances during the forest's lifetime, and greenhouse gas (GHG) emissions associated with the reforestation are not allowed for. This study uses life cycle assessment to quantify the carbon footprint of setting up a reforestation plot in the Peruvian Amazon. In parallel, we combine a soil carbon model with an above- and below-ground plant carbon model to predict the increase in carbon stocks after planting. We compare our results with the carbon capture claims made by a reforestation platform. Our results show major errors in carbon accounting in reforestation projects if they (1) ignore the time needed for trees to reach their carbon capture potential; (2) ignore the GHG emissions involved in setting up a plot; (3) report the carbon capture potential per tree planted, thereby ignoring limitations at the forest ecosystem level; or (4) under-estimate tree losses due to inevitable human and climatic disturbances. Further, we show that applications of biochar during reforestation can partially compensate for project emissions.


Asunto(s)
Ciclo del Carbono , Carbono/química , Conservación de los Recursos Naturales , Bosques , Biomasa , Brasil , Bases de Datos Factuales , Ecosistema , Modelos Teóricos , Perú , Programas Informáticos , Suelo/química , Árboles
15.
Arch Virol ; 155(3): 371-8, 2010 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-20052599

RESUMEN

Glycoprotein 4 (GP4) of porcine reproductive and respiratory syndrome virus (PRRSV) contains a highly variable neutralizing epitope. The present study aimed to investigate whether this epitope is susceptible to immunoselection by antibodies in vitro. Cultivation of PRRSV in vitro in the continuous presence of neutralizing monoclonal antibodies (mAbs) directed against this epitope resulted in the selection of mAb-resistant PRRSV strains within five passages. Comparison of the GP4 amino acid (aa) sequence of the original PRRSV strain with the GP4 aa sequences of the mAb-resistant PRRSV strains revealed aa substitutions within this epitope. In conclusion, this study shows that the neutralizing epitope on GP4 is susceptible to immunoselection by antibodies in vitro.


Asunto(s)
Anticuerpos Neutralizantes/inmunología , Anticuerpos Antivirales/inmunología , Epítopos de Linfocito B/inmunología , Virus del Síndrome Respiratorio y Reproductivo Porcino/inmunología , Selección Genética , Proteínas Virales/inmunología , Secuencia de Aminoácidos , Sustitución de Aminoácidos/genética , Animales , Línea Celular , Análisis Mutacional de ADN , Datos de Secuencia Molecular , Mutación Missense , Análisis de Secuencia de ADN , Pase Seriado , Porcinos
16.
Prev Vet Med ; 181: 104704, 2020 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-31196699

RESUMEN

Capripox viruses are the causative agents of important animal diseases in cattle (Lumpy Skin Disease), sheep (Sheeppox) and goats (Goatpox) with severe socio-economic impact in case of wide scale outbreaks. Therefore there is a constant need for adequate diagnostic tools. The assays must be fit-for-purpose to identify the virus quickly and correctly and to be useful for surveillance and monitoring at different stages of an epidemic. Different diagnostic performance characteristics are required depending on the situation and the test purpose. The need for high throughput, high specificity/sensitivity and the capability for differentiating field virus strains from vaccine strains drives the development of new and better assays preferably with an advantageous cost-benefit balance. This review aims to look at existing and new virological and serological diagnostic tools used in the control against diseases caused by Capripox viruses.


Asunto(s)
Capripoxvirus/aislamiento & purificación , Enfermedades de las Cabras/diagnóstico , Dermatosis Nodular Contagiosa/diagnóstico , Infecciones por Poxviridae/veterinaria , Pruebas Serológicas/veterinaria , Enfermedades de las Ovejas/diagnóstico , Animales , Bovinos , Enfermedades de las Cabras/virología , Cabras , Dermatosis Nodular Contagiosa/virología , Virus de la Dermatosis Nodular Contagiosa/aislamiento & purificación , Infecciones por Poxviridae/diagnóstico , Infecciones por Poxviridae/virología , Sensibilidad y Especificidad , Ovinos , Enfermedades de las Ovejas/virología , Oveja Doméstica
17.
Sci Rep ; 10(1): 19479, 2020 11 10.
Artículo en Inglés | MEDLINE | ID: mdl-33173109

RESUMEN

Sugarcane (Saccharum officinarum L.) cultivation leaves behind around 20 t ha-1 of biomass residue after harvest and processing. We investigated the potential for sequestering carbon (C) in soil with these residues by partially converting them into biochar (recalcitrant carbon-rich material). First, we modified the RothC model to allow changes in soil C arising from additions of sugarcane-derived biochar. Second, we evaluated the modified model against published field data, and found satisfactory agreement between observed and predicted soil C accumulation. Third, we used the model to explore the potential for soil C sequestration with sugarcane biochar in São Paulo State, Brazil. The results show a potential increase in soil C stocks by 2.35 ± 0.4 t C ha-1 year-1 in sugarcane fields across the State at application rates of 4.2 t biochar ha-1 year-1. Scaling to the total sugarcane area of the State, this would be 50 Mt of CO2 equivalent year-1, which is 31% of the CO2 equivalent emissions attributed to the State in 2016. Future research should (a) further validate the model with field experiments; (b) make a full life cycle assessment of the potential for greenhouse gas mitigation, including additional effects of biochar applications on greenhouse gas balances.

18.
Front Vet Sci ; 7: 466, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32974391

RESUMEN

Nigeria is a large densely populated country in West Africa. Most of its livestock is raised in a pastoralist production system with typical long distance migration in search of water and feed. As the demand for animal products largely exceeds the domestic production, large numbers of livestock are imported from neighboring countries without sanitary restrictions. In Nigeria, foot-and-mouth disease virus (FMDV) serotypes O, A, and Southern African Territories (SAT)2 are endemic for a long time. Clinical outbreaks of FMD due to serotype SAT1 are described again since 2015, after an absence of more than 30 years. Historically, outbreaks of FMD due to serotypes O, A, SAT1, and SAT2 were each time associated with trade of cattle entering Nigeria from neighboring countries. In the present study, tissue samples from 27 outbreaks of FMD were collected in Nigerian cattle from 2012 until 2017 in six different States and in the Federal Capital Territory. FMDV was isolated and serotyped and further characterized by VP1 sequencing and phylogenetic analysis to gain more knowledge on FMDV circulation in Nigeria. Half of the outbreaks were characterized as FMDV topotype O/EA-3, while outbreaks with other serotypes and topotypes were-in descending order-less prevalent: A/Africa/G-IV, SAT1/X, SAT2/VII, and O/WA. The high dynamics and omnipresence of FMD in Nigeria were illustrated in Plateau State where FMDV serotypes O, SAT1, and SAT2 were isolated during the course of the study, while at some point in the study, outbreaks due to FMDV serotype A were observed in three remote States. The genetic and phylogenetic analysis suggests a mixed origin of FMD outbreaks. Some outbreaks seem to be caused by sustained local transmission of FMDV strains present in Nigeria since a number of years, while other outbreaks seem to be related to recent incursions with new FMDV strains. The role of African buffaloes in the etiology of FMD in Nigeria is unclear, and sampling of wildlife is needed. The results of the present study suggest that systematic sample collection is essential to understand the complex concomitance of FMDV strains in Nigeria and essential to support the implementation of a vaccination-based control plan.

19.
J Virol Methods ; 276: 113786, 2020 02.
Artículo en Inglés | MEDLINE | ID: mdl-31765721

RESUMEN

Foot-and-mouth disease virus (FMDV) is a highly variable RNA virus existing as seven different serotypes. The antigenic variability between and within serotypes can limit the cross-reactivity and therefore the in vivo cross-protection of vaccines. Selection of appropriate vaccine strains is crucial in the control of FMD. Determination of indirect relationships (r1-value) between potential vaccine strains and field strains based on antibody responses against both are routinely used for vaccine matching purposes. Aiming at the investigation of the repeatability, reproducibility and comparability of r1-value determination within and between laboratories and serological tests, a small scale vaccine matching ring test for FMDV serotype A was organized. Well-characterized serum pools from cattle vaccinated with a monovalent A24/Cruzeiro/Brazil/55 (A24) FMD vaccine with known in vivo protection status (homologous and heterologous) were distributed to four laboratories to determine r1-values for the heterologous FMD strains A81/Argentina/87, A/Argentina/2000 and A/Argentina/2001 using the virus neutralization tests (VNT) and liquid phase blocking ELISA (LPBE). Within laboratories, the repeatability of r1-value determination was high for both antibody assays. VNT resulted in reproducible and comparable r1-values between laboratories, indicative of a lack of antigenic relatedness between the A24 strain and the heterologous strains tested in this work, thus corresponding to some of the in vivo findings with these strains. Using LPBE, similar trends in r1-values were observed in all laboratories, but the overall reproducibility was lower than with VNT. Inconsistencies between laboratories may at least in part be attributed to differences in LPBE protocols as well as the in preexisting information generated in each laboratory (such as antibody titer-protection correlation curves). To gain more insight in the LPBE-derived r1-values standard bovine control sera were included in the antibody assays performed in each laboratory and a standardization exercise was performed.


Asunto(s)
Fiebre Aftosa/inmunología , Pruebas Serológicas/normas , Pruebas Serológicas/veterinaria , Vacunas Virales/inmunología , Animales , Bovinos , Fiebre Aftosa/prevención & control , Pruebas de Neutralización , Variaciones Dependientes del Observador , Reproducibilidad de los Resultados , Vacunas Virales/administración & dosificación
20.
NPJ Vaccines ; 5(1): 1, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-31908850

RESUMEN

Foot and mouth disease (FMD) is a highly contagious viral disease with high economic impact, representing a major threat for cloven-hooved mammals worldwide. Vaccines based on adjuvanted inactivated virus (iFMDV) induce effective protective immunity implicating antibody (Ab) responses. To reduce the biosafety constraints of the manufacturing process, a non-replicative human adenovirus type 5 vector encoding FMDV antigens (Ad5-FMDV) has been developed. Here we compared the immunogenicity of iFMDV and Ad5-FMDV with and without the ISA206VG emulsion-type adjuvant in sheep. Contrasted Ab responses were obtained: iFMDV induced the highest Ab levels, Ad5-FMDV the lowest ones, and ISA206VG increased the Ad5-FMDV-induced Ab responses to protective levels. Each vaccine generated heterogeneous Ab responses, with high and low responders, the latter being considered as obstacles to vaccine effectiveness. A transcriptomic study on total blood responses at 24 h post-vaccination revealed several blood gene module activities correlating with long-term Ab responses. Downmodulation of T cell modules' activities correlated with high responses to iFMDV and to Ad5-FMDV+ISA206VG vaccines as also found in other systems vaccinology studies in humans and sheep. The impact of cell cycle activity depended on the vaccine types, as it positively correlated with higher responses to iFMDV but negatively to non-adjuvanted Ad5-FMDV. Finally an elevated B cell activity at 24 h correlated with high Ab responses to the Ad5-FMDV+ISA206VG vaccine. This study provides insights into the early mechanisms driving the Ab response induced by different vaccine regimens including Ad5 vectors and points to T cell modules as early biomarker candidates of different vaccine-type efficacy across species.

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