Preparation and evaluation of an experimental iscom-based infectious bursal disease vaccine

The present study was conducted to develop and evaluate an experimental ISCOM-based infectious bursal disease (IBD) vaccine. The indigenous very virulent infectious bursal disease virus (vvIBDV) already attenuated and adapted to Vero cell line was used. After denaturation of viral proteins with sodium dodecyl sulphate (SDS), an IBD-ISCOM was constructed. The non-incorporated viral components were separated from ISCOM by centrifugation of dialysate. The pathogenicity and immunogenicity trials were conducted in 3-week-old broiler chicken. A commercial oil-emulsified vaccine (CEVAC IBD K) was used for comparison. There were no clinical signs of disease, gross or microscopic lesions in bursa of Fabricius in group G1 vaccinated with ISCOM-based vaccine and bursa to body weight ratio were comparable to un-vaccinated control group (G3). The virus-neutralizing antibody titers were significantly (P<0.05) higher in group G1 as compared with group G2 which was vaccinated with commercial vaccine. On challenge with vvIBDV, 100%, 75% and 0.00% protection was achieved in G1, G2 and G3, respectively. The results indicated that ISCOM-based IBD vaccine is safe and immunogenic.     

Outline of the arcuate nucleus in the human medulla oblongata.

The outline of the arcuate nucleus in the human medulla oblongata was studied in a series of serial sections of brain stems of newborn and young children. The nucleus lies on the ventral aspect of the pyramid. At higher levels the nucleus lies on the ventral and medial aspect of the pyramid. In the upper regions of the medulla the two nuclei fuse together, giving rise to a median dorsal extension, which in the uppermost part of the medulla extends to the floor of the fourth ventricle. The nucleus sends numerous branches to the corticospinal portion of the pyramidal tract, while the dorsal extension of the arcuate nucleus sends numerous transverse rays on either side which consist of nerve fibres and cells. These rays extend in the areas of the medulla occupied by the medial lemniscus, tectospinal portion, and medial longitudinal bundle. The significance of the findings is discussed.     

Suppression of pulmonary and systemic vascular histamine H2-receptors in allergic sheep

We have previously demonstrated a depression of airway H2-receptor function in sheep allergic to Ascaris suum antigen. To investigate whether this is a generalized defect, we studied the H1- and H2- histamine receptor functions in the pulmonary and systemic circulations of allergic and nonallergic sheep. Pulmonary arterial pressure, and cardiac output were measured for calculation of pulmonary vascular resistance (PVR) and systemic vascular resistance (SVR) before and immediately after a rapid intrapulmonary infusion of histamine (10 micrograms/kg), with and without pretreatment with H1- (chlorpheniramine) and H2- (metiamide) antagonists. Histamine alone increased mean PVR to 435 and 401% of base line and decreased mean SVR by 51 and 54% in the nonallergic and allergic sheep, respectively (P less than 0.001). In the nonallergic sheep following pretreatment with chlorpheniramine (selective H2 stimulation) or metiamide (selective H1 stimulation), histamine decreased SVR by 18 and 36%, respectively, suggesting that approximately two-thirds of the vasodepressor response was mediated by H1-receptors and one-third by H2-receptors. Combined H1- and H2-antagonists completely blocked the histamine response. In allergic sheep the histamine-induced decrease in SVR was primarily mediated by H1-receptors, because the response was blocked by H1-antagonist, chlorpheniramine, and the H2-antagonist, metiamide, had no effect. In the pulmonary circulation selective H1-stimulation caused a similar increase in PVR in allergic (365%) and nonallergic sheep (424%), whereas selective H2-stimulation caused a significant decrease in PVR in the nonallergic group (14%) but not in the allergic group.(ABSTRACT TRUNCATED AT 250 WORDS)     

WSV 2019: The First Committee Meeting of the World Society for Virology

The World Society for Virology (WSV) was founded and incorporated as a nonprofit organization in the United States in 2017. WSV seeks to strengthen and support both virological research and virologists who conduct research of viruses that affect humans, other animals, plants, and other organisms. One of the objectives of WSV is to connect virologists worldwide and support collaboration. Fulfilling this objective, virologists from fourteen countries in North America, Europe, Africa, Asia, and the Middle East met on 25–27th August 2019 in Stockholm, Sweden at the Karolinska University Hospital for the first Committee Meeting of WSV. This meeting included compelling keynote and honorary speeches and a series of 18 scientific talks were given encompassing a diverse array of subjects within virology. Followed by the scientific session, a business session was held where multiple aspects and next steps of the society were discussed and charted out.