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Analysis of variabilitiy and antigenic peptides prediction of E2 BVDV glicoproteiniIn a Mucosal Diseases affected animal
No full text
Analisi della variabilità e predizione di peptidi antigenici della glicoproteina E2 del BVDV in un soggetto con malattie delle mucose
No full textThe E2 protein is the major glycoprotein of the envelope of Bovine Viral
Diarrhea virus (BVDV). This protein is highly variable and induces a strong immune response
with the production of neutralizing antibodies; therefore this protein is widely used to set up
vaccines providing complete protection from the infection. In persistently infected animals it
was assumed that immunological tolerance favoured maintenance of an antigenically conserved
population of persisting virus over the emergence of quasispecies which stimulate an effective
immune response. However, further studies showed genetic variability of BVDV in the E2
region and 5’UTR region in persistent infected animals. The aim of our work was to study the
variability of BVDV analysing the antigenic properties of clones obtained by cloning PCR
products of two organs from mucosal disease affected anima
Viral quantification of bovine viral diarrhea virus (BVDV) with Real Time PCR
No full textBVDV is responsible of persistent infection (PI) in cattle. PI animals can develop a severe pathology, the Mucous Disease (MD). The aim of this work was to develop a Real Time PCR (qRT-PCR) in order to quantify the virus amount in different organs and apparatus from PI and MD affected animals.
In order to set up a qRT-PCR a recombinant plasmid was constructed cloning a highly conserved fragment of 5’UTR region and serial dilutions were used to obtain a standard curve. Viral RNA was extracted from organs of 3 animals and it was retrotranscripted and quantified by SYBR green qRT-PCR.
The Real Time assay was able to detect 10-20 copies of DNA/l. Inter-assay tests showed a coefficient of variability ranging from 1,2% to 3,8%. With the quantification of BVDV we observed a higher amount of virus in the MD affected animals respect to PI animal. This difference resulted statistically significant in some organs of respiratory and digestive apparatus, but not considering the whole amount of virus in the animals.
Quantitative RT-PCR permitted to quantify the BVDV in different organs from PI and MD affected animals and resulted to be useful to study the distribution and the amount of the virus. The “not statistically significant” lower level of the total virus in PI animal could be correlated with the MD post mortem lesions evidenced in this animal that didn’t showed clinical symptoms. The method revealed to be sensitive and rapid and it is suitable for both diagnostic and pathogenesis studies
Cinnamosma Macrocarpa and its fractions are active in vitro against Betanodavirus
No full textBetanodavirus is the causative agent of viral encephalopathy and retinopathy (VER). VER is considered one of the most serious viral diseases in aquaculture causing enormous losses in species of high economic value as sea bass and halibut (1). No commercial vaccine is available and the most efficacious countermeasures against VER are the traditional prophylactic methods (2). Cinnamosma is widely used in traditional medicine and it’s active in vitro against several viruses (3). In this study we evaluated the in vitro efficacy of the essential oil of Cinnamosma macrocarpa against Betanodavirus. The cytotoxicity (CC50) of the oil was determined on SSN-1 cells comparing treated cells with untreated control cells by coulter counter and the antiviral activity (IC50) by the cytopathic effect inhibition assay. The selectivity index (SI) was calculated as the ratio of CC50 and IC50. Due to the efficacy exhibited by Cinnamosma oil, 7 fractions obtained from column chromatography with different degree of polarity were tested to identify the fraction of the oil responsible for the antiviral activity. Three fractions showed intracellular antiviral activity with values ranging from 21 mg/ml to 54 mg/ml and cytotoxicity between 100 mg/ml and 200 mg/ml. The SI varied from 3 to 4.8. The most polar extracts were the most effective. Cinnamosma oil and its polar fractions were active against the in vitro replication of Betanodavirus. Further studies are needed to elucidate the mechanism of action and to investigate the efficacy of Cinnamosma derivatives in vivo as a possible candidate to treat VER disease.
References:
1-Samuelsen O., Nerland AH., Jorgensen T., Schroder MB., Svasand T., Bergh O. (2006). Dis. Aquat. Organ. 71(3):239-54.
2-Harinantenaina L., Yoshinori A., De Clerq E. (2007). J. Nat. Prod. 70, 277-2
Analysis of variability and antigenic peptides prediction of E2 BVDV glycoprotein in a mucosal disease affected animal
No full textThe aim of our work was to study the genetic variability of BVDV and the quasispecies nature of the virus. Clones were obtained by cloning PCR products of E2 viral genome starting from two organs of a mucosal disease affected animal and a prediction of the antigenic sites of E2 protein portion was then performed.
Two PCR products of E2 region of BVDV with genetic variability obtained from organs of a MD affected animal were cloned and screened with SSCP technique. Two or more clones with the same pattern in SSCP analysis were sequenced and the amino acid sequences were predicted and analyzed for theirs antigenic properties by several programs.
Three different SSCP banding patterns were obtained from abomasums derived cloned. Eleven clones out of 31 obtained from abomasum were sequenced and a predicted fragment of 125 amino acids of E2 protein were subjected analysis. Nine clones out of 61 obtained from tonsils were sequenced and the predicted amino acid sequences were analyzed. The antigenic analysis by Kolaskar and Tongaonkar method evidenced the presence of 4 immunogenic peptides in 9 clones obtained from the abomasums and two clones showed another antigen site at the position 16-23. This result was confirmed by the antigenic analysis based on Jameson-Wolf approach. In particular clone 10 showed an additional antigenic peak, in the correspondent graphic, between the amino acids 20-25. Except clone 10 no significant differences in the antigenic profile was evidenced in the other clones whereas similar profiles were obtained with Emini method. About clones from tonsils the prediction of antigenic peptides by Kolaskar and Tongaonkar method evidenced in 8 samples the 4 immunogenic peptides observed in the abomasum; only one clone presented the antigenic site at the position 16-23. Also in this case the application of method Jameson and Wolf showed in this clone an antigenic peak between 20-25 amino acids. All clones demonstrated the same profile by Emini analysis.
The presence of viral variants in the abomasum and tonsils were evidenced by SSCP analysis showing the existence of viral quasispecies in a subject with mucosal disease. The antigenic index analysis and the prediction of regions on the surface of the E2 protein confirmed the high level of immunogenicity of this region. The antigenic analysis of predicted protein showed different regions able to induce a humoral immune response from the host. Some viral variants evidenced an additional antigenic site; however seems to be possible the selection of a viral population with a lower antigenic degree able to elude the immune system of the host.
These results demonstrate the high evolutionary ability of BVDV and the skill to evade the immune response by the selection of viral population with a lower antigenic property
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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