43 research outputs found

    The use of self-assembled receptor layers in immunosensors

    Get PDF
    We demonstrate that a self-assembled monolayer consisting of an alkylthiol coupled synthetic peptide adsorbed to a gold substrate results in a sensitive receptor surface for specific recognition of protein molecules. The affinity constant of this binding is comparable with that of an antibody-antigen reaction. Evidence is found that such a receptor surface is capable of reversible binding

    Molecular biological methods for studying the gut microbiota : the EU human gut flora project

    Get PDF
    Seven European laboratories co-operated in a joint project (FAIR CT97-3035) to develop, refine and apply molecular methods towards facilitating elucidation of the complex composition of the human intestinal microflora and to devise robust methodologies for monitoring the gut flora in response to diet. An extensive database of 16S rRNA sequences for tracking intestinal bacteria was generated by sequencing the 16S rRNA genes of new faecal isolates and of clones obtained by amplification with polymerase chain reaction (PCR) on faecal DNA from subjects belonging to different age groups. The analyses indicated that the number of different species (diversity) present in the human gut increased with age. The sequence information generated, provided the basis for design of 16S rRNA-directed oligonucleotide probes to specifically detect bacteria at various levels of phylogenetic hierarchy. The probes were tested for their specificity and used in whole-cell and dot-blot hybridisations. The applicability of the developed methods was demonstrated in several studies and the major outcomes are described

    Maturation of Gut Microbiota and Circulating Regulatory T Cells and Development of IgE Sensitization in Early Life

    Get PDF
    Recent studies suggest that the cross-talk between the gut microbiota and human immune system during the first year of life is an important regulator of the later development of atopic diseases. We explored the changes in the gut microbiota, blood regulatory T cells, and atopic sensitization in a birth-cohort of Estonian and Finnish children followed from 3 to 36 months of age. We describe here an infant Treg phenotype characterized by high Treg frequency, the maturation of Treg population characterized by a decrease in their frequency accompanied with an increase in the highly activated Treg cells. These changes in Treg population associated first with the relative abundance of Bifidobacterium longum followed by increasing colonization with butyrate producing bacteria. High bifidobacterial abundance in the neonatal microbiota appeared to be protective, while colonization with Bacteroides and E. coli was associated with later risk of allergy. Estonian children with lower risk of IgE mediated allergic diseases than Finnish children showed an earlier maturation of the gut microbiota, detected as earlier switch to an increasing abundance of butyrate-producing bacteria, combined with an earlier maturation of Treg cell phenotype and total IgE production. The children with established allergic diseases by age 3 showed a decreased abundance of butyrate producing Faecalibacterium. These results suggest that as well as the maintenance of a bifidobacterial dominated gut microbiota is important during the first weeks of life, the overtake by butyrate producing bacteria seems to be a beneficial shift, which should not be postponed

    The influence of different adjuvants on the immune response to a synthetic peptide comprising amino acid residues 9–21 of herpes simplex virus type 1 glycoprotein D

    No full text
    The immuno-modulating properties of different adjuvant systems on the murine humoral and cellular immune response to a synthetic peptide comprising amino acid residues 9–21 of glycoprotein D of herpes simplex virus type 1 (HSV-1) were investigated. For immunization, the peptide was conjugated to ovalbumin or bovine serum albumin by glutaraldehyde and the adjuvants used in this study were Freund's complete adjuvant (FCA), aluminium hydroxide, the Ribi adjuvant system (RAS) and two non-ionic block polymer surfactants, viz. L101 and 31R1, in oil in water emulsions. High anti-peptide antibody titers were obtained after immunization with FCA, aluminium hydroxide, RAS and L101. All adjuvants, except RAS, stimulated the induction of delayed type hypersensitivity obtained after immunization with peptide 9–21 coupled to ovalbumin and elicited by injection of purified HSV-1 virions in the footpad. Challenge with a lethal dose of HSV-1 showed that mice immunized with peptide 9–21 coupled to ovalbumin in combination with FCA, RAS and L101, respectively, were significantly protected. Although immunization with peptide 9–21 coupled to ovalbumin combined with aluminium hydroxide stimulated induction of delayed type hypersensitivity, no significant protective immunity against the challenge was generate

    The Winding-Up and Restructuring Act: Realigning Insolvency Law’s Orphan to the Modern Insolvency Law Process

    No full text
    The Winding-Up and Restructuring Act (WURA) is an important pan of Canada\u27s insolvency law structure. Insolvent banks and insurance companies may only be liquidated under WURA and are excluded from the Bankruptcy and Insolvency Act (BIA) and the Companies\u27 Creditors Arrangement Act (CCAA). However, WURA has been neglected and many of its provisions reflect its nineteenth century origins. The most recent round of insolvency reforms in S.C. 2005, c. 47 and S.C. 2007, c. 36 do not make any substantive changes to WURA. BIA and CCAA have been modernized over time; WURA is the orphan of insolvency law reform. The article examines whether WURA should remain a distinct statute and if so, whether it should be limited to financial institutions. The article considers specific areas of reform in relation to pre-bankruptcy transactions, the role of inspectors, preferred claims and Crown priority
    corecore