1,721,010 research outputs found
Avian Influenza virus serological study among poultry workers in Iran
No full textObjective: Since the mid-1990s, H9N2 subtype influenza A viruses have caused infections in the poultry population
around the globe, including several countries in Asia, Europe, North Africa and America. H9N2 influenza
viruses are currently circulating in the Middle and Far East, as well as in European poultry, and the infection
seems to be endemic in most developing countries.
A significant proportion of recent H9N2 isolates contains the L-226 mutation in their hemagglutinin (HA) receptor-
binding site and shows preferential binding to analogs of receptors with α2,6-linked sialic acid (SA), which
are traits typical of human viruses. Thus, these avian viruses might possess one of the key elements for infection
in humans. The H9N2 virus was isolated for the first time from humans in Hong Kong in 1999 and until now
different human cases of AI H9N2 have been reported in different countries. The wide circulation of H9N2 viruses
throughout Europe and Asia, along with their ability to cause direct infection in mammals and humans, raises
public health concerns about their potential to become candidates for the next influenza pandemic (Li KS et
al.2003) in addition to the H5N1 virus. Since 1998 H9N2 AI has been reported in Iran (Nili H. 2003) and at present
is endemic in the poultry industry; despite the control measures, which include mass vaccination of poultry,
this virus has spread rapidly and is currently circulating in the country (Vasfi Marandi M.2013). This study
was carried out to reveal the potential exposure to H9N2 AI viruses among Iranian poultry workers.
Methods: A total of 200 subjects took part in this study, including 100 poultry workers and 100 healthy residents.
Serum samples were collected and tested for the presence of antibodies against two different H9N2 avian
influenza viruses by haemagglutination inhibition (HI) and microneutralization (MN) assays, the analyses were
repeated at least three times. Two Iranian H9N2 strains were isolated in 1998 and 2008, which showed different
phylogenetic and important molecular differences at aa 226 (Q/L) (H3 numbering),
(A/chicken/Iran/12VIR/9630/1998)/Q, (A/chicken/Iran/10VIR/854-5/2008)/L. The viruses were replicated in SPF
chicken eggs and used in the serological study as antigens. In addition, all samples were tested for the presence
of seasonal H3N2, H1N1 2009 pandemic human influenza viruses to verify the presence of cross positivity
with the previously listed influenza viruses.
Results: Serological results showed that 16% of the exposed poultry workers were positive for the
A/chicken/Iran/10VIR/854-5/2008 virus in MN test and 12.33% in HI test using the titer > 40 as positive cut-off
value. Only 2% of the exposed staff was positive for the A/chicken/Iran/12VIR/9630/1998 virus. Seroprevalence
of control subjects for both H9N2 strains was very low in both tests (1-2%).
Conclusion: The results of this study have demonstrated that exposure to avian H9N2 viruses had occurred
among poultry workers in the Shiraz region – Iran, with a higher percentage than that recorded in the control
population of the same geographic area. Continuous surveillance programmes should be implemented to monitor
the presence of avian influenza infections in humans and to evaluate their potential threat to public health
and poultry workers
Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Variations on the Author
Full text link“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
Appropriate Similarity Measures for Author Cocitation Analysis
Full text linkWe provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis
Avian Influenza in Italy. The role of non-industrial (rural) sectors.
No full textAim of this study was to delineate the role of rural and industrial poultry sectors in the epidemiology of avian influenza in Italy
Prodotti ittici trasformati. Così si identificano le specie.
No full textFiletti, bocconcini,
crocchette.
Sempre più di frequente
i prodotti ittici
vengono commercializzati
in porzioni pronte
per il consumo.
Come fare per identificare
le specie ittiche utilizzate?
Il sistema biomolecolare
può essere una soluzione..
Low pathogenic avian influenza in Italy
No full textFrom 24 May to 30 October 2007, sixteen low pathogenicity avian influenza (LPAI) outbreaks caused by a type A AI virus of the H7N3 subtype occurred in Northern Italy. Ten outbreaks were identified in rural or hobby flocks containing different poultry and ornamental bird species. Most of the affected premises were detected during the implementation of the national AI monitoring plan and at the time of sampling none of the birds showed any symptoms. Epidemiological investigations revealed commercial links (movement of live birds) between 8 of these farms. From 22 August to 2 October 2007 six infected meat turkey farms were identified in the Lombardy Region. These birds showed mild respiratory disease associated with anorexia and a slightly increased mortality rate
Epidemiology and Control of Low Pathogenicity Avian Influenza Infections in Rural Poultry in Italy
No full textWe analyzed the involvement of the rural poultry sector in outbreaks of low pathogenicity avian influenza (AI) in
Italy in 2007–2009 and discuss possible measures for improving monitoring and control. A description of how the rural poultry
sector is organized also is provided. Data were obtained by the AI surveillance system established in the areas affected by the
outbreaks. The surveillance activities identified two H7N3 epidemics, in 2007 and 2009, both of which mainly involved the rural
sector, yet these activities did not allow for the prompt eradication of the disease. Additional strategies could be adopted to avoid
the persistence of AI within the rural sector, based on the regulation and control of poultry holdings at the top of the production
chain
SVILUPPO E APPLICAZIONE DI TEST DIAGNOSTICI MOLECOLARI PER L’IDENTIFICAZIONE E LA CARATTERIZZAZIONE DEI VIRUS DELLA MALATTIA DI MAREK CIRCOLANTI IN ITALIA
No full textMarek's disease (MD) is one of the most common lymphoproliferative diseases of chickens which causes mononuclear infiltration of different tissues and organs, such as peripheral nerves, gonad, viscera, muscle and skin. It is caused by an Alphaherpesvirus, called MDV or Gallid Herpesvirus 2 (GaHV-2). Although it has been studied in all its aspects from the early ‘60s and vaccines are now used all over the world, many issues remain unresolved due to the complexity of the disease. In order to activate specific surveys in the field, the IZSVe has developed a series of molecular diagnostic methods for the MD. The development of these tests makes a rapid and robust diagnosis possible, allowing to distinguish the vaccine strains from those pathogens and to identify the pathotype in a short time. Samples from backyard farms, samples (environmental dust, feathers, spleens and livers) taken from an industrial flock of breeders in the first months of life, as well as samples from clinical cases of particular interest were analysed for validation of the methods.
The data obtained so far confirm the high presence of Marek's disease in rural farms. The low number of outbreaks in industrial flocks lead us to believe that currently used chicken genetic lines and the vaccinations adopted are in most cases appropriate to counter the circulating viruses, which have mostly a medium-low pathogenic power. The detection of pathogenic viruses in the environment, even in farms with high standards of biosecurity which undergo intensive cleaning and disinfection cycles, highlights the importance of proper vaccination practices
- …
