327,505 research outputs found
Lymphocystis virus disease
No full textLymphocystis disease (LCD) is a chronic self-limiting disease involving a number of teleost species throughout the world. It is caused by the lymphocystis disease virus (LCDV) and characterized by white nodules affecting the fish's skin/fins. Although LCD is frequently benign, it may be responsible for economic losses related to poor growth, nonmarketability of diseased fish, and secondary bacterial infections. Currently, no specific prevention or therapeutic methods are available, and the control is based on the application of a biosecurity program including disinfection procedures, screening and quarantine of fish stocks that have to be introduced. Recent studies showed that LCDV causes systemic infection, and surviving fish can become asymptomatic carriers, thus presenting new challenges in the control of LCD. This chapter reviews the literature providing an overview of this insidious disease, including recent insights on pathogenesis and epidemiology, available methods for the diagnosis and future prospects to improve LCD control
Infezioni da Betanodavirus nei pesci. Diffusione in Europa ed epidemiologia molecolare.
No full textNella relazione viene presentata la situazione epidemiologica dell'infezione da Betanodavirus con particolare riferimento alla situazione europea ed alle indagini di epidemiologia molecolare effettuate presso il laboratorio di virologia del Dipartimento di Sanità Pubblica veterinaria dell'Università di Bologna
Tecnologie di ripresa digitale per lo studio di fenomeni transitori in contatti non conformi lubrificati
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Genetic characterisation of coat protein gene of betanodavirus isolates from different fish species
No full textValutazione della risposta immunitaria in soggetti persistentemente infetti da BVDV mediante quantificazione citochinica
No full textLa Diarrea Virale Bovina è una patologia infettiva responsabile di gravi danni nell’allevamento bovino. Nonostante la malattia sia ben conosciuta e studiata da molti decenni ancora non è possibile controllare efficacemente né l’effetto immodepressivo, né l’infezione congenita che conseguono all’infezione del suo agente causale (virus della diarrea virale bovina - BVDV). Questa situazione è prevalentemente dovuta alle carenti conoscenze che si hanno sull’effetto dell’infezione virale sul sistema immunitario dell’ospite. L’obiettivo della nostra indagine è stato pertanto quello di valutare lo stato d’immunodepressione in 12 soggetti con infezione naturale da BVDV. A tal fine è stata comparata l’espressione genica delle citochine interleuchina 8 (IL-8) e interferone gamma (IFN-γ) misurata, tramite real time PCR in diversi organi linfoidi provenienti da soggetti infetti e sani. L’espressione genica è stata poi direttamente correlata alla presenza del virus quantificato tramite PCR quantitativa. L’indagine ha mostrato più bassi valori di RNA messaggero dei mediatori ricercati nei campioni derivanti dai soggetti infetti. Inoltre è stata evidenziata una più bassa espressione citochinica negli organi com maggior quantità di virus anche se tale correlazione non ha trovato conforto statistico. Gli Autori discutono delle possibili ragioni di tale riscontro. dimostrando una minore capacità reattiva della risposta immunitaria cellulo-mediata e dell’attività chemiotattica nei soggetti infetti con BVDV
Evaluation of cytokines expression by Real time PCR from organs and blood of persistent infected animals by BVDV
No full textThe aim of this study was to apply the Real time PCR technique to tissues and blood samples of persistently infected animals and healthy animals in order to evaluate the expression of cytokines as INF-γ, IL-8, IL-1β and IL-10.
Eighty-one samples of organs from 15 animals both BVDV persistently infected (PI) and healthy were collected and analyzed for cytokines expression. Following cytokines were quantify with a real time PCR technique: INF-γ, IL-8, IL-1β and IL-10.
The quantification of cytokines expression from organs by Real time PCR showed differences between PI and healthy animals. Both INF-γ and IL-8 expressions were down-regulated in the organs from PI animals compared to healthy animals, and the INF-γ decrease was statistically significant (P< 0,001) in each group of organs analyzed.
The expression of each cytokine evaluated on buffy coat was different depending on the time point considered. Only IL-8 was quantified in each time point reaching a peak of expression at the ninth blood collection and its level was higher than that one of other cytokines. INF-γ expression was detectable among the seventh and the ninth blood collection; IL-1β among the second and the sixth blood collection and IL-10 between the sixth and the seventh blood collection. Cytokine levels of PI and healthy animals were almost comparable and no statistically significant differences were observed.
This study put in evidence that Real time PCR is a suitable technique for the quantification of cytokines. We found a reduction of cytokines expression (INF-γ and IL-8) from organs of PI animals compared to control animals confirming the activity of BVDV on the immune system. The INF-γ down-regulation could be due to the immunotolerance phenomenon and to the ability of the virus to infect persistently without triggering an antiviral state. In blood samples of PI and healthy animals cytokine levels were almost comparable, but the expression curves were different. The detection of INF-γ only at 3 time points out of 10 confirms the hypothesis that in PI animals there is not an effective antiviral state and that CD4+ and CD8+ depletion decreases the expression of this cytokine. As demonstrated on organs analysis there is no difference between the expression of IL-8 in PI and healthy animals probably because of its function as neutrophil chemotactic factor at the inflammation site. IL-10 is a modulatory cytokine mainly decreasing other soluble factor as IL-1 β. The reduction of this cytokine since the sixth blood collection could be correlated to the higher level of IL-10. In conclusion our results demonstrate that Real time PCR is a useful technique in the study of cytokine expression and further studies are justified to increase the panel of cytokines to be evaluated in order to better understand the role of these soluble factors in the immune response against BVDV
Universal Curve for pi pi Scattering Lengths by Optimal Extrapolation Techniques
No full textUsing the method of optimal extrapolation to interior points, we re-evaluate the equation of the universal curve of the ππs-wave scattering lengths. We reproduce the gross features of previous determinations, but with a realistic error, without any detailed assumption on the asymptotic behaviour. Possible implications of our result on the numerical value of thep-wave scattering length are qualitatively discussed
Is The Froissart Bound Saturated In Proton Proton Scattering?
No full textProton-proton and antiproton-proton forward data are analysed in the framework of a recently suggested stable unbiased approach to the asymptotic properties of total cross-sections. The resulting picture favours values of the leading logarithmic coefficient α such that 0≤α≲1
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