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The coronaviruses (CoV) are ubiquitous pathogens found in wide variety of hosts that constantly pose a threat to human and animal health as a result of their enormous capacity to generate genetic changes. Constant monitoring of virus reservoirs can constitute an early-warning tool and control the spread and evolution of the virus. Coronaviruses are common in wild birds, globally, and birds of the Charadriiformes in particular have been demonstrated to be carriers of delta- (dCoV) and gammacoronaviruses (gCoV). In this paper, we present the genetic characterisation of five CoV strains from black-headed (Chroicocephalus ridibundus) and common (Larus canus) gulls. Whole genome sequence analysis showed high similarity of detected dCoV in gulls to previously identified strains from falcon, houbara, pigeon and gulls from Asia (UAE, China). However, phylogenetic analysis revealed bifurcation within a common branch. Furthermore, the accumulation of numerous amino acid changes within the S-protein was demonstrated, indicating further evolution of dCoV within a single gull host. In turn, phylogenetic analysis for the most of the structural and non-structural genes of identified gCoV confirmed that the strain belongs to the duck coronavirus 2714 (DuCoV2714) species within Igacovirus subgenera, while for the spike protein it forms a separate branch not closely related to any gCoV species known to date. The current study provides new and significant insights into the evolution and diversification of circulating coronaviruses in members of Laridae family.
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Charadriiformes , Infecções por Coronavirus , Coronavirus , Gammacoronavirus , Animais , Humanos , Deltacoronavirus , Filogenia , Columbidae , Coronavirus/genética , Gammacoronavirus/genéticaRESUMO
Infectious bursal disease virus is an immunosuppressive ubiquitous pathogen that causes serious economic losses in poultry production. The virus is prone to genetic changes through mutations and reassortment, which drive the emergence of new variants and lead to a change in the epidemiological situation in a field. Such a situation is currently being reported due to a large wave of IBDV A3B1 reassortant infections in northwestern Europe. On the other hand, in Poland, which is the largest producer of chicken meat in the EU, the IBDVs of genotypes A3B2 and A3B4 were circulating just before the emergence of A3B1 reassortants. The purpose of the presented study was to update the IBDV epidemiological situation. The performed molecular survey based on the sequence of both genome segments showed the presence of very virulent strains (A3B2) and reassortants of genotypes A3B4 and A3B1; moreover, two of these genotypes are newly introduced IBDV lineages. In addition, a number of amino acid substitutions were demonstrated, including within antigenic epitopes and virulence determinants. In conclusion, the results obtained indicated a dynamic epidemiological situation in Poland, which highlights the need for further monitoring studies in the region and verification of protection conferred by the vaccines used against infection with detected IBDV.
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Vírus da Doença Infecciosa da Bursa , Polônia/epidemiologia , Vírus da Doença Infecciosa da Bursa/genética , Europa (Continente) , Substituição de Aminoácidos , EpitoposRESUMO
Infectious bursal disease virus is an immunosuppressive pathogen that, despite applied vaccination, is affecting the poultry industry worldwide. This report presents the genetic and pathotypic characterization of a natural reassortant emerging in Europe (Latvia). Genetic characterization showed that strain 25/11/Latvia/2011 represents genotype A3B1, whose segment A is derived from very virulent strains, while segment B is from the classic-like genogroup. Phylogenetic maximum likelihood inference of the B-segment sequence clustered the reassortant strain together with the US antigenic variant E strain. However, the obtained full-length sequence of 25/11/Latvia/2011 revealed that not only reassortment but also dozens of mutations shaped the unique genetic makeup. Phenotypic characterization showed no mortality and no clinical signs of disease but a severe bursa of Fabricius atrophy and splenomegaly in the convalescent birds at 10 days post infection. The results obtained indicate that the acquired genetic constellation contributed to a decrease in virulence; nevertheless, the infection causes severe damage to lymphoid organs, which can lead to impaired immune responses.
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The only knowledge of the molecular structure of European turkey coronaviruses (TCoVs) comes from France. These viruses have a quite distinct S gene from North American isolates. The aim of the study was to estimate the prevalence of TCoV strains in a Polish turkey farm during a twelve-year period, between 2008 and 2019, and to characterize their full-length S gene. Out of the 648 flocks tested, 65 (10.0%, 95% CI: 7.9-12.6) were positive for TCoV and 16 of them were molecularly characterized. Phylogenetic analysis showed that these strains belonged to two clusters, one formed by the early isolates identified at the beginning of the TCoV monitoring (from 2009 to 2010), and the other, which was formed by more recent strains from 2014 to 2019. Our analysis of the changes observed in the deduced amino acids of the S1 protein suggests the existence of three variable regions. Moreover, although the selection pressure analysis showed that the TCoV strains were evolving under negative selection, some sites of the S1 subunit were positively selected, and most of them were located within the proposed variable regions. Our sequence analysis also showed one TCoV strain had recombined with another one in the S1 gene. The presented investigation on the molecular feature of the S gene of TCoVs circulating in the turkey population in Poland contributes interesting data to the current state of knowledge.
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Coronavirus do Peru , Enterite Transmissível dos Perus , Animais , Coronavirus do Peru/genética , Epidemiologia Molecular , Filogenia , Polônia/epidemiologia , PerusRESUMO
The revealed prevalence of coronaviruses in wild bird populations in Poland was 4.15% and the main reservoirs were birds from orders Anseriformes and Charadriiformes, with a prevalence of 3.51% and 5.59%, respectively. Gammacoronaviruses were detected more often than deltacoronaviruses, with detection rates of 3.5% and 0.7%, respectively. Gammacoronaviruses were detected in birds belonging to six orders, including Anseriformes, Charadriiformes, Columbiformes, Galliformes, Gruiformes, and Passeriformes, indicating a relatively wide host range. Interestingly, this was the only coronavirus detected in Anseriformes (3.51%), while in Charadriiformes, the prevalence was 3.1%. The identified gammacoronaviruses belonged to the Igacovirus and Brangacovirus subgeneras. Most of these were igacoviruses and formed a common phylogenetic group with a Duck Coronavirus 2714 and two with an Avian Coronavirus/Avian Coronavirus9203, while the viruses from the pigeons formed a distinct "pigeon-like" group, not yet officially represented. The presence of deltacoronaviruses was detected in birds belonging to three orders, Charadriiformes, Galliformes, and Suliformes indicating a narrower host range. Most identified deltacoronaviruses belonged to the Buldecovirus subgenus, while only one belonged to Herdecovirus. Interestingly, the majority of buldecoviruses were identified in gulls, and they formed a distinct phylogenetic lineage not represented by any officially ratified virus species. Another separate group of buldecoviruses, also not represented by the official species, was formed by a virus identified in a common snipe. Only one identified buldecovirus (from common pheasant) formed a group with the ratified species Coronavirus HKU15. The results obtained indicate the high diversity of detected coronaviruses, and thus also the need to update their taxonomy (establishing new representative virus species). The serological studies performed revealed antibodies against an infectious bronchitis virus in the sera of white storks and mallards.
Assuntos
Animais Selvagens/virologia , Biodiversidade , Doenças das Aves/virologia , Infecções por Coronavirus/veterinária , Gammacoronavirus/isolamento & purificação , Animais , Animais Selvagens/classificação , Anseriformes/virologia , Charadriiformes/virologia , Columbiformes/virologia , Infecções por Coronavirus/virologia , Patos/virologia , Galliformes/virologia , Gammacoronavirus/classificação , Gammacoronavirus/genética , Filogenia , PolôniaRESUMO
Infectious bronchitis virus (IBV) is one of the most important poultry pathogens, leading significant economic losses worldwide. IBV is characterised by highly genetic, serotype, and pathotypic variability. Despite extensive immunoprophylaxis strategies, the emergence of new genetic lineages is frequently observed in the field, causing disease control to be more complicated. In the last decade, the spread of variants assigned to the GI-23 lineage of IBV (formerly known as Var2) started from Middle-Eastern countries and reached Europe in the last few years. Recently, the introduction and fast spread of Var2-like IBVs in Poland was reported. In this study, the virulence properties and efficacy of different vaccination programmes were evaluated against infection with the IBV GI-23 strain gammaCoV/Ck/Poland/G052/2016. The pathogenicity of the Var2 isolate was conducted in one-day-old and three-week-old SPF chickens and showed that the course of the disease is age dependent. Seven vaccination programmes using Mass, 793B, QX alone or in combination, and Var2 live vaccines were tested against the GI-23 infectious bronchitis virus challenge. All groups were scored according to the ciliostasis test at 5 days post challenge. Two immunoprophylaxis strategies generated full protection against gammaCoV/Ck/Poland/G052/2016 infection-Var2 and Mass used in one-day-old chickens boosted by a combination of the QX and 793B vaccine (both with a ciliostasis score of 0 and 100% protection).
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The circulation in Europe of novel reassortant strains of infectious bursal disease virus (IBDV), containing a unique genetic background composition, represents a serious problem for animal health. Since the emergence of this novel IBDV mosaic was first described in Poland, this scenario has become particularly attractive to uncover the evolutionary forces driving the genetic diversity of IBDV populations. This study additionally addressed the phenotypic characterization of these emergent strains, as well as the main features affecting the viral fitness during the competition process of IBDV lineages in the field. Our results showed how different evolutionary mechanisms modulate the genetic diversity of co-existent IBDV lineages, leading to the error catastrophe effect, Muller ratchet effect, or prevalence, depending on their genetic compositions. We also determined that the action of the positive selection pressure, depending on the genomic segment on which it is acting, can drive two main phenotypes for IBDV: immune-escaping strains from the selection on segment A or strains with functional advantages from the selection on segment B. This last group seems to possess an increased fitness landscape in the viral quasispecies composition, presenting better adaptability to dissimilar environmental conditions and likely becoming the dominant population. The reassortant strains also exhibited a lower mortality rate compared with the well-known vvIBDV strains, which can facilitate their spreading.
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Infecções por Birnaviridae/veterinária , Evolução Molecular , Variação Genética , Genoma Viral , Vírus da Doença Infecciosa da Bursa/genética , Vírus Reordenados/genética , Animais , Infecções por Birnaviridae/virologia , Galinhas/virologia , Aptidão Genética , Vírus da Doença Infecciosa da Bursa/classificação , Vírus da Doença Infecciosa da Bursa/patogenicidade , Fenótipo , Filogenia , Doenças das Aves Domésticas/virologia , Organismos Livres de Patógenos Específicos , Virulência/genética , Replicação ViralRESUMO
Infectious bursal disease virus (IBDV) is the aetiological agent of a highly contagious chicken immunodeficiency disorder known as Gumboro disease, which cause severe economic loses to the poultry worldwide. The emergence of very virulent IBDV strains (vvIBDV) during the late 80s resulted in drastic changes to the epidemiology of IBDV with a dramatic increase in the mortality of the animals affected. Molecular studies determined that the emergence of the vvIBDV was a consequence of a genomic reorganization of IBDV known as reassortant event by which the virus combined two emergent genetic background vvIBDV for segment A and vvIBDV for segment B. In the current study, a retrospective analysis was conducted, and samples collected during acute outbreaks of Gumboro disease in Poland during 1992-2015 were submitted to sequencing and further molecular and phylogenetic analyses. The results obtained not only revealed a high genetic diversity for Polish IBDV strains but a new population of IBDV was identified. These novel reassortant strains with a unique genetic background contain the segment A from very virulent strains and segment B from an unidentified source, phylogenetically segregated and classified as 'transitional lineage'. The results obtained also showed the presence of this new lineage in Finland, evidencing the expansion of this new genomic reorganized viral strain in Europe representing an additional threat to the global situation of IBDV.
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Infecções por Birnaviridae/veterinária , Surtos de Doenças/veterinária , Vírus da Doença Infecciosa da Bursa/isolamento & purificação , Doenças das Aves Domésticas/epidemiologia , Vírus Reordenados/isolamento & purificação , Doença Aguda , Animais , Infecções por Birnaviridae/epidemiologia , Infecções por Birnaviridae/virologia , Galinhas/virologia , Finlândia/epidemiologia , Genoma Viral , Vírus da Doença Infecciosa da Bursa/genética , Polônia/epidemiologia , Doenças das Aves Domésticas/virologia , Reação em Cadeia da Polimerase em Tempo Real/veterinária , Vírus Reordenados/genética , Estudos RetrospectivosRESUMO
Infectious bursal disease virus (IBDV) is the causative agent of a highly contagious immunosuppressive disease affecting young chickens. The recently described "distinct IBDV" (dIBDV) genetic lineage encompasses a group of worldwide distributed strains that share conserved genetic characteristics in both genome segments making them unique within IBDV strains. Phenotypic characterization of these strains is scarce and limited to Asiatic and European strains collected more than 15 years ago. The present study aimed to assess the complete and comprehensive phenotypic characterization of a recently collected South American dIBDV strain (1/chicken/URY/1302/16). Genetic analyses of both partial genome segments confirmed that this strain belongs to the dIBDV genetic lineage and that it is not a reassortant. Antigenic analysis with monoclonal antibodies indicated that this strain has a particular antigenic profile, similar to that obtained in a dIBDV strain from Europe (80/GA), which differs from those previously found in the traditional classic, variant and very virulent strains. Chickens infected with the South American dIBDV strain showed subclinical infections but had a marked bursal atrophy. Further analysis using Newcastle disease virus-immunized chickens, previously infected with the South American and European dIBDV strains, demonstrated their severe immunosuppressive effect. These results indicate that dIBDV strains currently circulating in South America can severely impair the immune system of chickens, consequently affecting the local poultry industry. Our study provides new insights into the characteristics and variability of this global genetic lineage and is valuable to determine whether specific control measures are required for the dIBDV lineage. Research Highlights A South American strain of the dIBDV lineage was phenotypically characterized. The strain produced subclinical infections with a marked bursal atrophy. Infected chickens were severely immunosuppressed. The dIBDV strains are antigenically divergent from other IBDV lineages.
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Infecções por Birnaviridae/veterinária , Galinhas/virologia , Vírus da Doença Infecciosa da Bursa/genética , Vírus da Doença Infecciosa da Bursa/imunologia , Doenças das Aves Domésticas/virologia , Animais , Infecções por Birnaviridae/imunologia , Infecções por Birnaviridae/virologia , Galinhas/imunologia , Genótipo , Imunogenicidade da Vacina , Terapia de Imunossupressão/veterinária , Vírus da Doença Infecciosa da Bursa/isolamento & purificação , Vírus da Doença Infecciosa da Bursa/patogenicidade , Fenótipo , Doenças das Aves Domésticas/imunologia , VirulênciaRESUMO
Infectious bursal disease virus (IBDV) is one of the most important immunosuppressive viral agents in poultry production. Prophylactic vaccinations of chicken flocks are the primary tool for disease control. Widely used immunoprophylaxis can, however, provide high pressure which contributes to the genetic diversification of circulating viruses, e.g. through reassortment of genome segments. We report the genetic and phenotypic characterization of a field reassortant IBDV (designated as Bpop/03) that acquired segment A from very virulent IBDV and segment B from classical attenuated D78-like IBDV. Despite the mosaic genetic make-up, the virus caused high mortality (80%) in experimentally infected SPF chickens and induced lesions typical of the acute form of IBD. The in vivo study results are in contrast with the foregoing experimental investigations in which the natural reassortants exhibited an intermediate pathotype, and underline the complex nature of IBDV virulence.
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Infecções por Birnaviridae/veterinária , Galinhas , Genoma Viral , Vírus da Doença Infecciosa da Bursa/fisiologia , Vírus da Doença Infecciosa da Bursa/patogenicidade , Doenças das Aves Domésticas/virologia , Vírus Reordenados/fisiologia , Vírus Reordenados/patogenicidade , Sequência de Aminoácidos , Animais , Infecções por Birnaviridae/virologia , Vírus da Doença Infecciosa da Bursa/genética , Filogenia , Polônia , Vírus Reordenados/genética , VirulênciaRESUMO
Variants assigned to GI-23 lineage of infectious bronchitis virus (IBV), formerly called Var2, have circulated for nearly 20 years only in countries of the Middle East. Strains of this lineage were first identified in Israel in 1998. More severe form of the virus appeared in 2006, when the second wave of Var2 epidemic has spread over the Middle East region. The present study describes the detection and detailed genetic characterization of the GI-23 viruses in Poland. The full-length genome of gammaCoV/Ck/Poland/G052/2016 strain consists of 27596 nucleotides and has typical organization for IBV (UTR5'-POl-S-3a-3b-E-M-4b-4c-5a-5b-N-UTR3'). The phylogenetic analysis of the complete sequence showed that it formed separate branch distinct from all of the full-length genome sequences analyzed in this study. Recombination analyses with other gammacoronaviruses revealed that Polish GI-23 strain may originate from recombination events and potential donors of build-in sequences are IBV of GI-1, GI-13 and G-19 lineages (Mass-, 793B- and QX-like strains, respectively). The 1a, 1b and N genes were involved in these recombination events. The source of virus introduction to the chicken population in Poland is unknown.
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Galinhas/virologia , Vírus da Bronquite Infecciosa/classificação , Vírus da Bronquite Infecciosa/isolamento & purificação , Animais , Ordem dos Genes , Genoma Viral , Genótipo , Vírus da Bronquite Infecciosa/genética , Filogenia , Polônia , Recombinação Genética , Análise de Sequência de DNA , Homologia de SequênciaRESUMO
INTRODUCTION: Infectious bursal disease virus (IBDV) is a causative agent of immunosuppressive disorder resulting in significant losses to the world poultry industry. This study describes the molecular characterisation of an atypical IBDV from a field outbreak that occurred in vaccinated chicken flocks in Latvia in 2011. MATERIAL AND METHODS: Ten bursae of Fabricius from each flock were collected for laboratory examination. Virus isolation was performed in embryonated eggs and CEF culture. The RT-PCR aimed at hypervariable domain of VP2 gene combined with sequencing was performed for detection and identification of IBDV. RESULTS: The molecular examinations confirmed the IBDV infection. The analysis of the amino acid sequence revealed that the strain possessed four amino acids at VP2 protein (222A, 256I, 294I, and 299S), indicating a genetic relatedness to a very virulent IBDV. However, some unique or rare amino acid substitutions (219L, 220F, 254D, 279N, and 280T) were also detected. CONCLUSION: The obtained results demonstrate the occurrence of IBDV with a high mutation rate within the hypervariable domain of VP2 peptide, and highlight the necessity of implementation of IBDV surveillance in Eastern European poultry industry to determine whether this strain is an exception or a new wave of IBDV with new genetic features emerged in the field.
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Chicken astrovirus (CAstV) was recently indicated as the factor of the "white chicks" condition associated not only with increased embryo/chick mortality but also with weakness and white plumage of hatched chicks. In February 2014, organ samples (livers and kidneys) from dead-in-shell embryos, as well as 1-day-old whitish and normal chicks, were delivered from one hatchery in Poland for disease diagnosis. The samples originated from the same 30-week-old breeder flock in which the only observed abnormal signs were 4-5% decrease in the number of hatched chickens and the presence (about 1%) of weaker chicks with characteristic whitish plumage among normal ones. CAstV was detected in submitted samples and was then isolated in 10-day-old embryonated specific pathogen free (SPF) chicken eggs. We also reproduced an infection model for the "white chicks" condition in SPF layer chickens using the isolated PL/G059/2014 strain as the infectious agent. Results of experimental reproduction of the "white chicks" condition were somewhat more serious than field observation. The administration of the CAstV material into the yolk sac of 8-day-old SPF chicken eggs caused delay and prolongation of hatching, as well as death of embryos/chicks, and also a change of plumage pigmentation. Only two chicks of a total of 10 inoculated SPF eggs survived and were observed for 2 months. A gradual elimination of the CAstV genome was noted in this period. Moreover, a few contact-naive SPF chicks, which had been placed in the same cage, were infected with CAstV. Molecular characterization of detected CAstV was performed by nucleotide sequencing of the full ORF2 region encoding the capsid precursor protein gene. Phylogenetic studies showed that the PL/G059/2014 isolate clustered in the subgroup Aiii of CAstV. In the light of the new classification rules, the Polish PL/G059/2014 CAstV isolate could be assigned to a new species of the Avastrovirus genus.
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Infecções por Astroviridae/veterinária , Avastrovirus/isolamento & purificação , Doenças das Aves Domésticas/virologia , Animais , Infecções por Astroviridae/virologia , Avastrovirus/genética , Proteínas do Capsídeo/genética , Galinhas , Filogenia , Polônia/epidemiologia , Análise de Sequência de DNA/veterinária , Organismos Livres de Patógenos EspecíficosRESUMO
A serological surveillance programme for avian influenza A virus (AIV) subtype H5 and H7 in poultry was implemented in Poland in 2008-2013 with two main objectives: i) to detect subclinical infections or previous exposures to AIV H5 and H7 subtypes and ii) to demonstrate the AI- free status of Poland. During this period, over 45 000 serum samples from 2833 holdings were examined using the hemagglutination inhibition test (HI). The presence of HI antibodies was detected in 8 breeder geese holdings (7 positive for H5 and 1 positive for H7 AIV) and in 1 breeder duck holding (H5-positive), which represented 0.32% of all investigated holdings. All seropositive flocks were examined by real time RT-PCR with negative results, which substantiated the AI-free status of Poland. Positive results detected in clinically healthy poultry kept in an open range system indicate prior infections with low pathogenic AIV originating from the wild-bird reservoir.
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Monitoramento Epidemiológico/veterinária , Vírus da Influenza A , Influenza Aviária/epidemiologia , Animais , Vírus da Influenza A/genética , Influenza Aviária/prevenção & controle , Polônia , Reação em Cadeia da Polimerase , Aves Domésticas , Estudos SoroepidemiológicosRESUMO
In April/May 2013, four outbreaks of avian influenza virus (AIV) infections caused by H9N2 subtype were diagnosed in Poland in fattening turkey flocks exhibiting a drop in feed and water intake, depression, respiratory signs and mortality. The subsequent serological survey carried out on samples collected between June 2012 and September 2013 from 92 poultry flocks detected positive sera in two additional meat turkey flocks located in the same province. The analysis of amino acids in the haemagglutinin and neuraminidase glycoproteins revealed that the detected H9N2 viruses possessed molecular profiles suggestive of low pathogenicity, avian-like SAα2,3 receptor specificity and adaptation to domestic poultry. Phylogenetic studies showed that these H9N2 AIVs grouped within the Eurasian clade of wild bird-origin AIVs and had no relationship with H9N2 AIV circulating in poultry in the Middle East and Far East Asia over the past decade. Experimentally infected SPF chickens with the index-case H9N2 virus remained healthy throughout the experiment. On the other hand, ten 3-week-old commercial turkeys infected via the oculonasal route showed respiratory signs and mortality (2/10 birds). Additional diagnostic tests demonstrated the consistent presence of DNA/RNA of Ornithobacterium rhinotracheale, Bordetella avium and, less frequently, of astro-, rota-, reo-, parvo- and adenoviruses in turkeys both from field outbreaks and laboratory experiment. Although no microbiological culture was performed, we speculate that these secondary pathogens could play a role in the pathogenicity of the current H9N2 infections.
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Galinhas , Surtos de Doenças/veterinária , Vírus da Influenza A Subtipo H9N2/isolamento & purificação , Influenza Aviária/virologia , Perus , Animais , Influenza Aviária/epidemiologia , Filogenia , Polônia/epidemiologia , Reação em Cadeia da Polimerase em Tempo Real , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Testes SorológicosRESUMO
To assess the susceptibility of pigeons (Columba livia) to infection with H5N1 high pathogenicity avian influenza virus (HPAIV), four groups of 1-yr-old and 4-wk-old racing pigeons (10 birds in each group) were inoculated oculonasally with 106 50% egg infectious dose (EID50) of A/crested eagle/Belgium/01/2004 (clade 1) or A/swan/Poland/305-135V08/2006 (clade 2.2). Contact specific-pathogen-free (SPF) chickens were kept in the same isolators as young pigeons (two chickens per group). At 3, 5, 7, 10, and 14 days postinfection (PI) two pigeons from each infected group were selected randomly, and oropharyngeal and cloacal swabs (pigeons and contact chickens) as well as a number of internal organs (pigeons) were collected for viral RNA detection in real-time reverse transcription PCR (RRT-PCR) and histopathology. At the end of the experiment (14 days PI) blood samples from two pigeons in each group and from contact SPF chickens were also collected, and sera were tested using hemagglutination inhibition (HI) test and blocking enzyme-linked immunosorbent assay (bELISA). During the observation period all pigeons remained clinically healthy, and no gross lesions were observed in any of the infected groups. SPF contact chickens were also healthy and negative in RRT-PCR and HI tests. However, the clade 1 H5N1 virus produced more sustained infection manifested by the presence of histopathologic changes (consisting mainly of mild to moderate hemorrhagic and inflammatory lesions), prolonged persistence of viral RNA (detectable between 3 and 10 days PI) in a variety of tissues of both adult and juvenile birds (with highest RNA load in lungs and brain) as well as slight viral shedding from the trachea and cloaca, but without transmission to SPF contact chickens. Additionally, two clade 1-infected adult pigeons sacrificed at the end of experiment showed seroconversion in bELISA and HI test (using homologous virus as antigen). The viral RNA was found only at day 3 PI in one adult pigeon inoculated with dade 2.2 H5N1 virus, but neither microscopic lesions nor seroconversion were found in any other tested birds inoculated with A/swan/Poland/305-135V08/2006. Our results support the observations that pigeons are resistant to H5N1 HPAIV (no deaths or clinical signs), but there may be clade-dependent differences in the pathogenic potentials of H5N1 HPAIV of Asian origin.
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Columbidae , Virus da Influenza A Subtipo H5N1 , Influenza Aviária/virologia , Animais , Encéfalo/patologia , Encéfalo/virologia , Suscetibilidade a Doenças , Influenza Aviária/imunologia , Fígado/patologia , Fígado/virologia , Pulmão/patologia , Pulmão/virologia , RNA Viral/genética , RNA Viral/isolamento & purificação , Baço/patologia , Baço/virologia , Traqueia/patologia , Traqueia/virologiaRESUMO
The aim of the study was to examine the effects of simultaneous acute exposure to cadmium (Cd) and in the presence of streptozotozin (STZ) on the central nervous system (CNS) memory processes in mice subjected to transient brain ischemia. In order to obtain transient brain ischemia, operative occlusion of common carotid arteries for 30 min was performed. Cadmium chloride was administered intraperitoneally (ip) after the surgery at a single dose of 0.1 LD(50) (LD(50) = 14 mg/kg). Disturbances in glucose metabolism in the brain tissue were induced by bilateral intracerebral administration of STZ, a drug that inhibits the function of a neuronal insulin receptor. Long-term memory was evaluated by means of a step-through passive avoidance task. Spatial working memory expressed as spontaneous alternations was tested in the Y-maze test. Coexposure to brain oligemia and STZ on the CNS produced significant impairment of long-term memory processes in mice. An additional exposure to Cd exacerbated the deficits of these processes. These results indicate that brain oligemia, Cd, and altered glucose metabolism may aggravate adverse effects on memory.
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Comportamento Animal/efeitos dos fármacos , Cádmio/farmacologia , Memória/efeitos dos fármacos , Estreptozocina/farmacologia , Animais , Encéfalo/efeitos dos fármacos , Encéfalo/metabolismo , Cádmio/efeitos adversos , Cádmio/metabolismo , Comportamento Exploratório/efeitos dos fármacos , Feminino , Hipovolemia/metabolismo , Ataque Isquêmico Transitório/metabolismo , Memória/fisiologia , Camundongos , Estreptozocina/efeitos adversos , Estreptozocina/metabolismoRESUMO
The aim of the study was to examine quantitative fluorine content in tooth tissues with the decay process, tissues of teeth without decay and tissues with diseases different than those of decay origin. It has been found that in the examined teeth decay process the average fluorine content in hard tissues amounted to 235.6 ppm of fluorine and it was lower than in healthy teeth (304.8 ppm) extracted for orthodontic or periodontological reasons, whereas the highest fluorine content--383.5 ppm--was found in teeth with diseases of non-decay etiology. Analyzing particular teeth groups depending on the age of the patients, it was observed that the fluorine level is higher in the teeth received from younger patients, especially in the group of healthy teeth and teeth with wedge defects. Susceptibility of tooth enamel to dissolution was estimated by the CRT test with the use of discs impregnated with crystal violet (hexamethylene-4 hydrochloride of fuchsin) with the range of colour change from yellow and green to violet and blue at ph 0.1-1.5. The lengthening of the time of reaction in this test testified to lower acid sensitivity of tissues and at the same time to harder demineralization of enamel, e.g. in the process of decay. Longer time of reaction was observed in teeth with higher indicated fluorine content.
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Cárie Dentária/metabolismo , Fluoretos/farmacocinética , Dente/metabolismo , Adolescente , Adulto , Idoso , Criança , Suscetibilidade à Cárie Dentária , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Potenciometria , Valores de Referência , Doenças Dentárias/metabolismoRESUMO
Allergic diseases have become recently an accretive medical as well as social problem, mainly in highly developed countries. Frequently they occur in the infancy and early childhood. In this analysis an attempt has been made to evaluate the occurrence of the allergic illnesses among 3-5 years old children living in the urban and rural environment. The research carried out has showed no significant differences in the occurrence of allergic diseases among children from cities and from rural areas.
Assuntos
Hipersensibilidade/epidemiologia , População Rural/estatística & dados numéricos , População Urbana/estatística & dados numéricos , Pré-Escolar , Estudos Transversais , Feminino , Inquéritos Epidemiológicos , Humanos , Masculino , PolôniaRESUMO
UNLABELLED: Chronic kidneys' failure as well as hemodialysis operations lead to disorders of many organs' and system's functions. We can observe a decrease in the immunulogical system's efficiency, which consequently causes the decrease in a human body's defence abilities. The dialysed patients are subject to a frequent contact with medical equipment and they require numerous examinations. All these factors, including the dialysis itself, increase the risk of occurrence of various types of infections, both bacterial and viral ones. The aim of the work was to try to define the kind and frequency of infectious diseases occurring among the dialysed patients. In order to conduct the research, the questionnaire among 50 patients in the centre of dialysis of the hospital in Chelm was made. Among the examined group, the most frequently occurring infectious diseases were infections of the ureter, bronchitis, flu and ear infection. Among 30% of the examined, inflammatory and thrombotic changes within a dialysis drainage tube occurred. 22% of the examined are the carriers of HBV. Among 36%, however, the antibodies of HCV were detected. CONCLUSIONS: 1. The hemodialysed patients make up a group that is at increased risk of infectious diseases. 2. The infection of B and C type is the exceptional problem among the hemodialysed patients. 3. The frequency of infectious diseases occurrence increases along with age and length of dialysotherapy. 4. Education of the patients about how to prevent infections brings measurable effects in the form of the decreasing number of morbidity cases.