1,720,959 research outputs found
Studio preliminare della risposta Immunitaria in giovanili di branzino (Dicentrarchus Labrax) sottoposti a vaccinazione contro la vibriosi.
No full textImmunizzazione di stadi giovanili di branzino (D. labrax) con un vaccino commerciale contro la vibriosi: monitoraggio della risposta immunitaria mediante ELISA e chemiluminescenza
No full textEvaluation of immunological parameters in farmed gilthead sea bream, Sparus aurata L., before and during outbreaks of 'winter syndrome'
No full textIn recent years, 'winter syndrome' has caused severe economic losses in many marine farms in southern Europe. This study compared the activity of the immune system in healthy, asymptomatic and diseased gilthead sea bream. Serum protein and immunoglobulin content were evaluated as well as serum complement activity from these groups of fish. Differential leucocyte counts were also determined. Immunological assays were performed to determine intra- and extracellular 'respiratory burst' activity as non-specific immune response parameters. Diseased fish showed a significant reduction in haemolytic activity (90%), and in serum proteins and immunoglobulins in comparison with the other groups. A significant increase in the lymphocyte percentage (50%) and a decrease in the granulocyte percentage (over 70%) was found in asymptomatic fish. Respiratory burst activity was reduced in both the clinical and preclinical stages of the disease, compared with the controls. These observations confirm a severe immunodeficiency in diseased fish but also the presence of a cellular immune dysfunction in fish without clinical signs, before the onset of the disease
Protective role and in vitro activity of fractions extracted from Lactococcus garvieae, the lactococcosis agent in rainbow trout (O. mykiss)
No full textEffective protocols of vaccination against lactococcosis in rainbow trout (O. mykiss) are still under investigation and the methods currently employed are based on “autovaccines” that are injected intraperitoneally to fish (Bercovier et al., 1997; Prearo, 2006). These vaccines allow a protection for 8 months, when integrated with adjuvants (Ravelo et al, 2006). The bacterial antigenic components involved in the protection are only partially considered by the literature. This investigation evaluated the effect of some fractions of L. garvieae (strain B05/3) in the development of a protective immune response to the infection. Extra cellular products (ECPs), bacterial whole cells (WCs) and membrane antigens (MAs) were injected intraperitoneum to 90g rainbow trouts. Fish were subsequently submitted to an intraperitoneal challenge with L. garvieae (2.6×105 cfu/individual). The relative percentages of survival (RPS) were 95% for WCs, 35% for ECPs and 33% for MAs. These results suggest that WCs provided the best protection, but also ECPs and MAs were effective.
Samples of serum collected from immunized and control fish were analysed by immunoblotting against the SDS-PAGE/Western Blotting protein profile of each bacterial fraction. The control and immunized fish sera contained immunoglobulins able to bind aspecifically the proteins having a molecular weight of 23, 48 and 102 kDa respectively. Similar findings were previously reported by Barnes et al., 2002.
Moreover the respiratory burst of leukocytes isolated from rainbow trout head kidney was measured by a luminol-based microtitre plate chemiluminescence assay after stimulation with the L. garvieae extracts. The tests were performed using 20 healthy non-immunized fish, by incubating the cells and the stimulants in presence and absence of autologous serum. Preliminary results suggest an evident individual variability in the response and that the release of reactive oxygen species is strongly affected by the serum addiction. This indicates an important role of antibodies and complement in promoting the leukocyte response to different antigens (Barnes et al., 2002). The specific stimulation ability of each fraction (WC, ECPs, MA) will be discussed
Valutazione della protezione indotta da frazioni antigeniche di Lactococcus garvieae in trota iridea (Oncorhynchus mykiss)
No full textSUMMARY – Effective procedures of vaccination against lactococcosis in rainbow trout (Oncorhynchus mykiss) are still under investigation and the methods currently employed are based on “autovaccines” that are injected intraperitoneally to fish. These vaccines allow a protection for 8 months, when integrated with adjuvants. The bacterial antigenic components involved in the protection are only partially considered by the literature. This investigation concerns the effect of some fractions of Lactococcus garvieae in the development of a protective immune response to the infection. Extracellular products (ECPs), bacterial whole cells (WCs) and membrane antigens (AM) were injected intraperitoneum to 90 g. rainbow trouts. Fish were subsequently submitted to an intraperitoneal challenge with L. garvieae (2.6×105 cfu/individual). The treatments allowed the following relative percentages of survival (RPS): 95% for WCs; 35% for ECPs, 33% for AM. These results suggest that WCs give the best protection, but also ECPs and AM are effective. Samples of serum collected from immunized and control fish were analysed by immunoblotting against the SDS-PAGE/Western Blotting protein profile of each bacterial fraction. The control and immunized fish sera contained immunoglobulins able to bind aspecifically the proteins having a molecular weight of 23, 48 and 102 kDa respectively
Valutazione della risposta anticorpale e della protezione indotta da un vaccino per immersione anti Yersinia ruckeri in trota iridea (Oncorhynchus mykiss)
No full textVaccini costituiti da batteri della specie Yersinia ruckeri, inattivati con formalina e somministrabili tramite immersione, sono disponibili in USA e in Europa a partire dalla fine degli anni ’70, per la profilassi della bocca rossa o “Enteric Redmouth Disease” (ERM). Nonostante siano state affrontate numerose prove sperimentali per indagare l’esito di questo intervento di profilassi in trota iridea (Oncorhynchus mykiss) risulta ancora poco definita la correlazione fra titoli anticorpali specifici e protezione indotta dal vaccino. L’obiettivo di questa indagine è stato quello di valutare in vivo la protezione indotta da un vaccino commerciale somministrato per immersione (30 secondi) a trote iridee di 5 grammi, tramite infezione sperimentale con un ceppo virulento di Yersinia ruckeri e di studiare la risposta anticorpale specifica indotta dal medesimo vaccino nelle settimane successive alla somministrazione. Tramite la tecnica di agglutinazione in micropiastra è stato possibile evidenziare la presenza di anticorpi agglutinanti nel siero dei soggetti trattati a partire da 7 settimane dopo la vaccinazione. La tecnica ELISA indiretta ha dimostrato una maggiore sensibilità, evidenziando titoli anticorpali significativamente più elevati rispetto ai controlli, a partire da 5 settimane dopo la vaccinazione. La percentuale relativa di sopravvivenza o RPS, collegata all’efficacia protettiva conferita dal vaccino commerciale, è risultata pari al 77% in seguito a prova di infezione intraperitoneale con 3x106 UFC/sogg., effettuata a 7 settimane dalla vaccinazione. Tale riscontro consente di ipotizzare che gli anticorpi sierici prodotti in seguito alla immunizzazione tramite immersione siano protettivi nei confronti della malattia
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
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