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2.
Animals (Basel) ; 11(3)2021 Mar 11.
Artigo em Inglês | MEDLINE | ID: mdl-33799904

RESUMO

The aim of this work was to develop processing methods that safeguard the quality and antimicrobial properties of H. illucens and B. mori oils. We adopted a vegetable diet for both insects: leftover vegetables and fruit for H. illucens and mulberry leaves for B. mori. First, alternative techniques to obtain a good oil extraction yield from the dried biomass of H. illucens larvae were tested. Traditional pressing resulted to be the best system to maximize the oil yield and it was successfully applied to B. mori pupae. Oil quality resulted comparable to that obtained with other extraction methods described in the literature. In the case of B. mori pupae, different treatments and preservation periods were investigated to evaluate their influence on the oil composition and quality. Interestingly, agar diffusion assays demonstrated the sensitivity of Gram-positive Bacillus subtilis and Staphylococcus aureus to H. illucens and B. mori derived oils, whereas the growth of Gram-negative Pseudomonas aeruginosa and Escherichia coli was not affected. This study confirms that fat and other active compounds of the oil extracted by hot pressing could represent effective antimicrobials against bacteria, a relevant result if we consider that they are by-products of the protein extraction process in the feed industry.

3.
Viruses ; 12(5)2020 05 22.
Artigo em Inglês | MEDLINE | ID: mdl-32456089

RESUMO

Mammalian Orthoreoviruses (MRV) are segmented dsRNA viruses in the family Reoviridae. MRVs infect mammals and cause asymptomatic respiratory, gastro-enteric and, rarely, encephalic infections. MRVs are divided into at least three serotypes: MRV1, MRV2 and MRV3. In Europe, swine MRV (swMRV) was first isolated in Austria in 1998 and subsequently reported more than fifteen years later in Italy. In the present study, we characterized two novel reassortant swMRVs identified in one same Italian farm over two years. The two viruses shared the same genetic backbone but showed evidence of reassortment in the S1, S4, M2 segments and were therefore classified into two serotypes: MRV3 in 2016 and MRV2 in 2018. A genetic relation to pig, bat and human MRVs and other unknown sources was identified. A considerable genetic diversity was observed in the Italian MRV3 and MRV2 compared to other available swMRVs. The S1 protein presented unique amino acid signatures in both swMRVs, with unexpected frequencies for MRV2. The remaining genes formed distinct and novel genetic groups that revealed a geographically related evolution of swMRVs in Italy. This is the first report of the complete molecular characterization of novel reassortant swMRVs in Italy and Europe, which suggests a greater genetic diversity of swMRVs never identified before.


Assuntos
Variação Genética , Orthoreovirus de Mamíferos/genética , Infecções por Reoviridae/virologia , Doenças dos Suínos/virologia , Animais , Proteínas do Capsídeo/genética , Chlorocebus aethiops , Europa (Continente) , Genoma Viral , Humanos , Itália , Mutação , Orthoreovirus de Mamíferos/classificação , Orthoreovirus de Mamíferos/isolamento & purificação , Filogenia , Sorogrupo , Suínos , Células Vero
4.
Artigo em Inglês | MEDLINE | ID: mdl-32322405

RESUMO

Norovirus (NoV) has emerged as one of the major causative agents of non-bacterial, food- and water-borne gastroenteritis in humans, with the main genogroup involved in human outbreaks (GII), which has been detected worldwide in different animal species including swine. A four-month investigation at the slaughterhouse aiming to examine the presence of NoV in the swine in North-Eastern Italy, enabled the detection of two divergent Noroviruses (NoVs) (GII.P11) in two swine farms. This represents the first study in the swine population of North-Eastern Italy, which has paved the way for future integrated virological and epidemiological investigations on swine NoVs.

5.
Vet Ital ; 55(3): 221-229, 2019 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-31599546

RESUMO

Porcine astroviruses (PoAstV) are found in the gastrointestinal tract of healthy and diseased pigs worldwide. However, their role in causing enteric disease in pigs and other animals has not been elucidated. In the present report, we describe for the first time in Italy, the identification and genetic characterization, through whole genome sequencing, of a PoAstV2 in pigs in Northeast Italy in 2015. This instance is the first detection of PoAstV2 in pigs in Italy. The phylogenetic analysis of the complete ORF2 segment highlights the high similarity of this virus to those circulating that same year in Japan. There are very few full astrovirus genomes available, and the present data represent an important contribution towards a better understanding of the characteristics and evolution of these viruses.


Assuntos
Infecções por Astroviridae/veterinária , Genoma Viral , Mamastrovirus/genética , Doenças dos Suínos/virologia , Animais , Infecções por Astroviridae/virologia , Fezes/virologia , Feminino , Itália , Mamastrovirus/classificação , Filogenia , Análise de Sequência de RNA/veterinária , Sus scrofa , Suínos , Sequenciamento Completo do Genoma/veterinária
6.
Talanta ; 203: 49-57, 2019 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-31202349

RESUMO

In this work, an electrochemical enzyme-linked oligonucleotide array to achieve simple and rapid multidetection of aflatoxin B1 (AFB1) is presented. The assay is based on a competitive format and disposable screen-printed cells (SPCs). Firstly, the electrodeposition of poly(aniline-anthranilic acid) copolymer (PANI-PAA) on graphite screen-printed working electrodes was performed by means of cyclic voltammetry (CV). Aflatoxin B1 conjugated with bovine serum albumin (AFB1-BSA) was then immobilized by covalent binding on PANI-PAA copolymer. After performing the affinity reaction between AFB1 and the biotinylated DNA-aptamer (apt-BIO), the solution was dropped on the modified SPCs and the competition was carried out. The biotinylated complexes formed onto the sensor surface were coupled with a streptavidin-alkaline phosphatase conjugate. 1-naphthyl phosphate was used as enzymatic substrate; the electroactive product was detected by differential pulse voltammetry (DPV). The response of the enzyme-linked oligonucleotide assay was signal-off, according to the competitive format. A dose-response curve was obtained between 0.1 ng mL-1 and 10 ng mL-1 and a limit of detection of 0.086 ng mL-1 was achieved. Finally, preliminary experiments in maize flour samples spiked with AFB1 were also performed.


Assuntos
Aflatoxina B1/análise , Aptâmeros de Nucleotídeos/química , Ácidos Nucleicos Imobilizados/química , Oligodesoxirribonucleotídeos/química , Aflatoxina B1/química , Fosfatase Alcalina/química , Técnicas Biossensoriais/métodos , Técnicas Eletroquímicas/instrumentação , Técnicas Eletroquímicas/métodos , Eletrodos , Farinha/análise , Contaminação de Alimentos/análise , Grafite/química , Limite de Detecção , Naftalenos/química , Compostos Organofosforados/química , Zea mays
7.
Toxins (Basel) ; 10(10)2018 10 16.
Artigo em Inglês | MEDLINE | ID: mdl-30332757

RESUMO

The aim of this study was to evaluate the potential use of an e-nose in combination with lateral flow immunoassays for rapid aflatoxin and fumonisin occurrence/co-occurrence detection in maize samples. For this purpose, 161 samples of corn have been used. Below the regulatory limits, single-contaminated, and co-contaminated samples were classified according to the detection ranges established for commercial lateral flow immunoassays (LFIAs) for mycotoxin determination. Correspondence between methods was evaluated by discriminant function analysis (DFA) procedures using IBM SPSS Statistics 22. Stepwise variable selection was done to select the e-nose sensors for classifying samples by DFA. The overall leave-out-one cross-validated percentage of samples correctly classified by the eight-variate DFA model for aflatoxin was 81%. The overall leave-out-one cross-validated percentage of samples correctly classified by the seven-variate DFA model for fumonisin was 85%. The overall leave-out-one cross-validated percentage of samples correctly classified by the nine-variate DFA model for the three classes of contamination (below the regulatory limits, single-contaminated, co-contaminated) was 65%. Therefore, even though an exhaustive evaluation will require a larger dataset to perform a validation procedure, an electronic nose (e-nose) seems to be a promising rapid/screening method to detect contamination by aflatoxin, fumonisin, or both in maize kernel stocks.


Assuntos
Aflatoxinas/análise , Contaminação de Alimentos/análise , Fumonisinas/análise , Zea mays , Aflatoxinas/imunologia , Anticorpos Imobilizados/imunologia , Nariz Eletrônico , Fumonisinas/imunologia , Imunoensaio
8.
Infect Genet Evol ; 58: 279-289, 2018 03.
Artigo em Inglês | MEDLINE | ID: mdl-29355607

RESUMO

Coronaviruses (CoVs) have been documented in almost every species of bat sampled. Bat CoVs exhibit both extensive genetic diversity and a broad geographic range, indicative of a long-standing host association. Despite this, the respective roles of long-term virus-host co-divergence and cross-species transmission (host-jumping) in the evolution of bat coronaviruses are unclear. Using a phylogenetic approach we provide evidence that CoV diversity in bats is shaped by both species richness and their geographical distribution, and that CoVs exhibit clustering at the level of bat genera, with these genus-specific clusters largely associated with distinct CoV species. Co-phylogenetic analyses revealed that cross-species transmission has been more common than co-divergence across coronavirus evolution as a whole, and that cross-species transmission events were more likely between sympatric bat hosts. Notably, however, an analysis of the CoV RNA polymerase phylogeny suggested that many such host-jumps likely resulted in short-term spill-over infections, with little evidence for sustained onward transmission in new co-roosting host species.


Assuntos
Doenças dos Animais/transmissão , Doenças dos Animais/virologia , Quirópteros/virologia , Infecções por Coronavirus/veterinária , Coronavirus/genética , Animais , Coronavirus/classificação , Evolução Molecular , Variação Genética , Genoma Viral , Especificidade de Hospedeiro , Filogenia , Filogeografia
9.
Vet Microbiol ; 195: 25-29, 2016 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-27771067

RESUMO

In August 2012 repeated respiratory outbreaks caused by swine influenza A virus (swIAV) were registered for a whole year in a breeding farm in northeast Italy that supplied piglets for fattening. The virus, initially characterized in the farm, was a reassortant Eurasian avian-like H1N1 (H1avN1) genotype, containing a haemagglutinin segment derived from the pandemic H1N1 (A(H1N1)pdm09) lineage. To control infection, a vaccination program using vaccines against the A(H1N1)pdm09, human-like H1N2 (H1huN2), human-like H3N2 (H3N2), and H1avN1 viruses was implemented in sows in November 2013. Vaccine efficacy was assessed by sampling nasal swabs for two months in 35-75 day-old piglets born from vaccinated sows. Complete genome sequencing of eight swIAV-positive nasal swabs collected longitudinally from piglets after the implementation of the vaccination program was conducted to investigate the virus characteristics. Over the two-month period, two different genotypes involving multiple reassortment events were detected. The unexpected circulation of multiple reassortant genotypes in such a short time highlights the complexity of the genetic diversity of swIAV and the need for a better surveillance plan, based on the combination of clinical signs, epidemiological data and whole genome characterization.


Assuntos
Genótipo , Vírus da Influenza A Subtipo H1N2/genética , Infecções por Orthomyxoviridae/veterinária , Doenças dos Suínos/virologia , Animais , Surtos de Doenças/veterinária , Vírus da Influenza A Subtipo H1N2/classificação , Itália/epidemiologia , Infecções por Orthomyxoviridae/epidemiologia , Infecções por Orthomyxoviridae/virologia , Filogenia , Suínos , Doenças dos Suínos/epidemiologia
11.
J Virol ; 90(14): 6401-6411, 2016 07 15.
Artigo em Inglês | MEDLINE | ID: mdl-27147741

RESUMO

UNLABELLED: Next-generation sequencing technology is now being increasingly applied to study the within- and between-host population dynamics of viruses. However, information on avian influenza virus evolution and transmission during a naturally occurring epidemic is still limited. Here, we use deep-sequencing data obtained from clinical samples collected from five industrial holdings and a backyard farm infected during the 2013 highly pathogenic avian influenza (HPAI) H7N7 epidemic in Italy to unravel (i) the epidemic virus population diversity, (ii) the evolution of virus pathogenicity, and (iii) the pathways of viral transmission between different holdings and sheds. We show a high level of genetic diversity of the HPAI H7N7 viruses within a single farm as a consequence of separate bottlenecks and founder effects. In particular, we identified the cocirculation in the index case of two viral strains showing a different insertion at the hemagglutinin cleavage site, as well as nine nucleotide differences at the consensus level and 92 minority variants. To assess interfarm transmission, we combined epidemiological and genetic data and identified the index case as the major source of the virus, suggesting the spread of different viral haplotypes from the index farm to the other industrial holdings, probably at different time points. Our results revealed interfarm transmission dynamics that the epidemiological data alone could not unravel and demonstrated that delay in the disease detection and stamping out was the major cause of the emergence and the spread of the HPAI strain. IMPORTANCE: The within- and between-host evolutionary dynamics of a highly pathogenic avian influenza (HPAI) strain during a naturally occurring epidemic is currently poorly understood. Here, we perform for the first time an in-depth sequence analysis of all the samples collected during a HPAI epidemic and demonstrate the importance to complement outbreak investigations with genetic data to reconstruct the transmission dynamics of the viruses and to evaluate the within- and between-farm genetic diversity of the viral population. We show that the evolutionary transition from the low pathogenic form to the highly pathogenic form occurred within the first infected flock, where we identified haplotypes with hemagglutinin cleavage site of different lengths. We also identify the index case as the major source of virus, indicating that prompt application of depopulation measures is essential to limit virus spread to other farms.


Assuntos
Evolução Biológica , Galinhas/virologia , Epidemias/veterinária , Variação Genética/genética , Vírus da Influenza A Subtipo H7N7/genética , Influenza Aviária/epidemiologia , Influenza Aviária/transmissão , Animais , Galinhas/genética , Sequenciamento de Nucleotídeos em Larga Escala , Influenza Aviária/virologia , Itália/epidemiologia , Filogenia
12.
Virus Genes ; 52(4): 573-7, 2016 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-27059240

RESUMO

Straw-colored fruit bats (Eidolon helvum), which have been identified as natural hosts for several zoonotic pathogens, such as lyssaviruses, henipaviruses, and ebolavirus, are associated with human settlements in Nigeria where they are commonly consumed as a delicacy. However, information on the viruses harbored by these bats is scarce. In this study, coronavirus sequences were detected using a nested RT-PCR targeting 440 bp of the RNA-dependent RNA polymerase (RdRp) in six of 79 fecal samples collected from an urban colony of E. helvum in Ibadan, Nigeria. Phylogenetic analysis revealed that all six sequences were monophyletic and clustered in lineage D of Betacoronavirus. The extension of two fragments allowed us to classify our sequences within the RdRp Group Unit defined for Kenyan Betacoronavirus from the same host species. These findings are consistent with the previous suggestion on the existence of a single epidemiological unit of E. helvum across sub-Saharan Africa. This theory, which is supported by the genetic structure of continental E. helvum, could facilitate viral mixing between different colonies across the continent.


Assuntos
Quirópteros/virologia , Coronavirus/genética , Animais , Infecções por Coronavirus/virologia , Quênia , Nigéria , Filogenia , Zoonoses/virologia
13.
Vet Microbiol ; 186: 102-10, 2016 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-27016764

RESUMO

In 1979, an avian influenza virus of the H1N1 subtype began to circulate in European swine herds, rapidly replacing classical swine H1N1 viruses. Spill-back transmissions to turkeys were recorded occasionally, but they might have been underreported due to the asymptomatic nature of the infection and the lack of specific surveillance. In our study, we evaluated the infectivity and transmissibility in turkeys of seven strains of H1N1 avian-like swine viruses isolated from 1979 to 2006, and compared them with their closest progenitor A/duck/Bavaria/1/77 (H1N1), to establish whether the adaptation to pigs has gradually decreased their fitness in turkeys. Our data indicate that the circulation of European H1N1 in pigs might have impaired the possibility of infecting turkeys. Nevertheless, the two swine-origin strains, which showed the ability to replicate and transmit in turkeys, possess typical swine-like genetic traits, not different from the rest of the tested isolates, suggesting replication of avian-like swine H1N1 viruses in turkeys as a strain-dependent polygenic feature.


Assuntos
Vírus da Influenza A Subtipo H1N1/classificação , Vírus da Influenza A Subtipo H1N1/genética , Influenza Aviária/transmissão , Influenza Aviária/virologia , Perus , Animais , Anticorpos Antivirais/sangue , Eritrócitos/virologia , Hemaglutininas/química , Especificidade de Hospedeiro , Humanos , Vírus da Influenza A Subtipo H1N1/imunologia , Vírus da Influenza A Subtipo H1N1/isolamento & purificação , Influenza Aviária/imunologia , Viabilidade Microbiana , Dados de Sequência Molecular , Mutação , Filogenia , Homologia de Sequência , Suínos , Doenças dos Suínos/virologia , Ligação Viral , Replicação Viral/fisiologia , Eliminação de Partículas Virais
15.
Infect Genet Evol ; 34: 457-66, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-26003682

RESUMO

Influenza A virus can quickly acquire genetic mutations that may be associated with increased virulence, host switching or antigenic changes. To provide new insights into the evolutionary dynamics and the adaptive strategies of distinct avian influenza lineages in response to environmental and host factors, we compared two distinct avian influenza epidemics caused by the H7N1 and H7N3 subtypes that circulated under similar epidemiological conditions, including the same domestic species reared in the same densely populated poultry area for similar periods of time. The two strains appear to have experienced largely divergent evolution: the H7N1 viruses evolved into a highly pathogenic form, while the H7N3 did not. However, a more detailed molecular and evolutionary analysis revealed several common features: (i) the independent acquisition of 32 identical mutations throughout the entire genome; (ii) the evolution and persistence of two sole genetic groups with similar genetic characteristics; (iii) a comparable pattern of amino acid variability of the HA proteins during the low pathogenic epidemics; and (iv) similar rates of nucleotide substitutions. These findings suggest that the evolutionary trajectories of viruses with the same virulence level circulating in analogous epidemiological conditions may be similar. In addition, our deep sequencing analysis of 15 samples revealed that 17 of the 32 parallel mutations were already present at the beginning of the two epidemics, suggesting that fixation of these mutations may occur with different mechanisms, which may depend on the fitness gain provided by each mutation. This highlighted the difficulties in predicting the acquisition of mutations that can be correlated to viral adaptation to specific epidemiological conditions or to changes in virus virulence.


Assuntos
Epidemias , Evolução Molecular , Vírus da Influenza A Subtipo H7N1/genética , Vírus da Influenza A Subtipo H7N3/genética , Influenza Aviária/virologia , Doenças das Aves Domésticas/virologia , Substituição de Aminoácidos , Animais , Frequência do Gene , Glicoproteínas de Hemaglutininação de Vírus da Influenza/química , Glicoproteínas de Hemaglutininação de Vírus da Influenza/genética , Influenza Aviária/epidemiologia , Funções Verossimilhança , Filogenia , Aves Domésticas/virologia , Doenças das Aves Domésticas/epidemiologia , Seleção Genética
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