A new influenza virus, genus D, isolated in US pigs and cattle, has also been circulating in cattle in France. It was first identified there in 2011, and an increase was detected in 2014. The virus genome in France is 94%–99% identical to its US counterpart, which suggests intercontinental spillover.
Lactic acid bacteria have become a major source of concern for aquaculture in recent decades. In addition to true pathogenic species of worldwide significance, such as Streptococcus iniae and Lactococcus garvieae, several species have been reported to produce occasional fish mortalities in limited geographic areas, and many unidentifiable or ill-defined isolates are regularly isolated from fish or fish products. To clarify the nature and prevalence of different fish-associated bacteria belonging to the lactic acid bacterium group, a collection of 57 isolates of different origins was studied and compared with a set of 22 type strains, using amplified rRNA gene restriction analysis (ARDRA). Twelve distinct clusters were delineated on the basis of ARDRA profiles and were confirmed by sequencing of sodA and 16S rRNA genes. These clusters included the following: Lactococcus raffinolactis, L. garvieae, Lactococcus l., S. iniae, S. dysgalactiae, S. parauberis, S. agalactiae, Carnobacterium spp., the Enterococcus "faecium" group, a heterogeneous Enterococcus-like cluster comprising indiscernible representatives of Vagococcus fluvialis or the recently recognized V. carniphilus, V. salmoninarum, and Aerococcus spp. Interestingly, the L. lactis and L. raffinolactis clusters appeared to include many commensals of fish, so opportunistic infections caused by these species cannot be disregarded. The significance for fish populations and fish food processing of three or four genetic clusters of uncertain or complex definition, namely, Aerococcus and Enterococcus clusters, should be established more accurately.
In France, a national surveillance plan to monitor congenital Schmallenberg virus (SBV) outbreaks was set up in January 2012, and has shown that SBV had become widespread throughout the country since mid-2011. However, the number of SBV-infected farms cannot accurately be estimated through congenital SBV reporting alone. Therefore, GDS France (National Animal Health Farmers' Organization) conducted serological investigations in cattle and sheep holdings in several departments in spring 2012 to assess SBV exposure in 2011. A serological study was also conducted in the department of Saône-et-Loire (southern Burgundy) to establish an accurate local overview of circulation of virus in 2011 among cattle. The study was conducted following guidelines elaborated by the French Platform for animal health surveillance. Results indicated differences in within-herd seroprevalence between cattle herds and sheep herds in departments where outbreaks of congenital SBV were reported in early 2012 and a great heterogeneity in seroprevalence between areas (even between areas geographically close to each other). In departments which had been severely affected in early 2012, the overall impact of SBV infection in cattle herds during the 2012-2013 calving season will probably be low. On the other hand, given the low proportion of immunised ewes in sheep SBV outbreaks, sheep flocks which were already affected in early 2012 may once again face congenital cases of SBV.
Our results show that in FcepsilonRI-stimulated RBL-2H3 cells calcium mobilization, activation of PKC and PI 3-kinase are necessary for TNF-alpha secretion while for the increased TNF-alpha mRNA expression PKC activity is dispensable and PI 3-kinase activity only partially required.
The vitronectin receptor is a member of the integrin family of adhesion protein receptors and binds a broad spectrum of ligands, including fibronectin and fibrinogen in addition to vitronectin. We have generated four mAbs that recognize the murine ␣v3 vitronectin receptor. Biochemical and expression analyses showed that two of the mAbs are specific for the ␣v chain, and two are specific for the 3 chain. The mAbs are effective blocking reagents and inhibited cell adhesion to vitronectin, fibrinogen, and fibronectin. Staining analysis revealed expression of ␣v and 3 on certain populations of murine thymocytes, splenocytes, and bone marrow cells. The expression of ␣v and 3 appeared to be modulated at specific stages of thymocyte development, suggesting a possible function for the ␣v3 vitronectin receptor in T cell development.Integrins comprise a large family of heterodimeric cell surface proteins composed of ␣ and  chains that mediate cell-cell interactions and interactions between cells and the extracellular matrix (ECM) (1-3). Integrins are expressed on all cells and are involved in a number of fundamental cell processes including adhesion, migration, activation, and differentiation. The expression and functions of integrins have been particularly well-studied with respect to lymphocytes, which require a variety of cell-cell and cell-ECM interactions to perform their complex programs of immune surveillance and antigen response (4, 5). The functions of integrins depend on binding to specific adhesion proteins, such as fibronectin, often through recognition of the tripeptide, arginine-glycine-aspartic acid (RGD), binding motif (6).The human ␣v3 vitronectin receptor was originally identified as a heterodimeric molecule with vitronectin binding activity (7), and later shown to be related to other members of the integrin family (8). Subsequent studies demonstrated that this receptor has a broad binding specificity and can mediate binding to fibronectin, fibrinogen, von Willebrand factor, and thrombospondin in addition to vitronectin (9-12). More recently, a mAb specific for the murine ␣v3 vitronectin receptor (␣v3) was isolated (13,14), and used to identify ␣v3 as a costimulatory molecule required for spontaneous activation of ␥␦ T cell hybridomas (15).In the process of identifying cell surface molecules involved in the constitutive interleukin 2 (IL-2) secretion of murine V␥1, V␦6 T cell hybridomas, we generated a series of monoclonal antibodies (mAbs) that recognize murine ␣v3. Here, we present the characterization of four of these mAbs, including the determination of their chain specificities and staining analysis of several lymphoid populations. Contrary to previous reports (13, 16), we observed detectable levels of ␣v and 3 expression on certain populations of thymocytes and splenocytes in addition to bone marrow cells. Interestingly, we observed differential expression of the ␣v and 3 chains on discrete populations of thymocytes, suggesting a possible role for this receptor in T cell develo...
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