Biomedical subjects

T Devos

Publications and source records attributed to T Devos.

4 recordsLinked to original sources

PubMed2000

Cloning and characterization of Leishmania donovani telomeres.

We describe here the cloning and sequence characterization of the absolute termini of several telomeres from the human parasite Leishmania donovani using a vector-adapter protocol. The 3' protruding strand of L. donovani telomeres terminates with the sequence 5'-GGTTAGGGT-OH 3'. This single-stranded sequence is adjacent to tandemly repeated blocks of double-stranded sequence consisting of variable numbers of the hexameric repeat 5'-TAGGGT-3', variable numbers of an octameric repeat 5'-TGGTCATG-3', and a single 62-bp sequence, in that order. A number of additional, more chromosome-internal, nonrepeated sequences were found adjacent to the telomere sequences. Hybridization analyses indicated that some of these telomere adjacent sequences are found on all L. donovani chromosomes, some are more abundant on certain subsets of chromosomes, and some are unique to individual chromosomes.

Animals↗

PubMed2000

Intergroup emotions: explaining offensive action tendencies in an intergroup context.

Three studies tested the idea that when social identity is salient, group-based appraisals elicit specific emotions and action tendencies toward out-groups. Participants' group memberships were made salient and the collective support apparently enjoyed by the in-group was measured or manipulated. The authors then measured anger and fear (Studies 1 and 2) and anger and contempt (Study 3), as well as the desire to move against or away from the out-group. Intergroup anger was distinct from intergroup fear, and the inclination to act against the out-group was distinct from the tendency to move away from it. Participants who perceived the in-group as strong were more likely to experience anger toward the out-group and to desire to take action against it. The effects of perceived in-group strength on offensive action tendencies were mediated by anger.

Affect↗

PubMed1997

[Secondary prevention of drug abuse: problems and examples].

Since 1992, the Federal Office of Public Health (FOPH) has been promoting an innovative approach of secondary drug use prevention. Our main purpose is to present this approach. For the FOPH, the objective of the measures in this field includes the development of concepts and means to detect, at an early stage, young people at risk, or whose drug consumption is recent or occasional, in order to help them. The basic principle of the strategy is to strengthen the protective role of the community network of the young people at risk. To illustrate this strategy, we briefly describe different projects supported by the FOPH; some of them are immediately launched on a national or regional scale, while others are innovative local or regional projects. Finally, we identify situations which are a priori more favourable to funding or support by the FOPH.

Adolescent↗

PubMedDate not supplied

Role of CD4+ and CD8+ T cells in the rejection of heart or islet xenografts in recipients with xenotolerance in the innate immune compartment.

UNLABELLED: To further study the interactions between innate and adaptive immunity in xenotransplantation, we explored the relative contribution of T-cell subsets in vascularized (heart) and cellular (islets) xenografts in a model with established xeno-non-reactivity of the innate system. MATERIALS: Specific innate xenotolerance was induced in xenoheart (hamster) recipients (nude rats) by a tolerizing regimen (TR), consisting of donor antigen infusion, temporary natural killer (NK)-cell depletion and a 4-week administration of leflunomide. Hamster pancreatic islets were transplanted either 1 week after heart transplantation or alone and syngeneic T-cell adoptive transfer was performed 10 days later. Purified CD3(+), CD4(+), and CD8(+) T cells were given 2 weeks after withdrawal of all drugs. At the day of rejection, xenografts were removed for histology. Serum was taken and IgM and IgG xenoantibody titers were measured by flow cytometry. RESULTS: Both heart and islet grafts were rejected after CD4(+) reconstitution. After CD8(+) T-cell adoptive transfer, cellular grafts were not rejected but vascularized grafts were rejected, although only after several months. Rejection in CD4(+) reconstituted nude rats was accompanied by the generation of predominantly IgG xenoantibodies. CONCLUSION: CD4(+) T lymphocytes are able to rapidly initiate the rejection of islet xenografts in the presence of a xenotolerant innate immune system either by breaking the "innate tolerance" (e.g., by activating macrophages and NK-cells) or through a mechanism without any involvement of the innate tolerance (e.g., T-dependent IgG antibody production). In contrast, CD8(+) T cells provoke a late rejection of only xenoheart grafts.

Animals↗