Heterogeneity in the supramolecular organization of immunological synapses arises from the involvement of different cells, distinct environmental stimuli, and varying levels of protein expression. ...There may also be heterogeneity in the types and amounts of cell surface proteins and lipids that transfer between lymphocytes during immune surveillance. In addition, immune cells can be involved in the assembly of a ‘viral synapse’, such that micrometer-scale organization of proteins at intercellular contacts occurs during transmission of a virus between T cells. Thus, while there may be unity in molecular mechanisms underlying the organization of cell surface receptors at immune cell synapses, there is diversity in their function.
As T cells and natural killer (NK) cells survey the surface of other cells, cognate receptors and ligands are commonly organized into distinct micrometer‐scale domains at the intercellular contact, ...creating an immune or immunological synapse (IS). We aim to address the still unanswered questions of how this organization of proteins aids immune surveillance and how these domains are biophysically constructed. Molecular mechanisms for the formation of the IS include a role for the cytoskeleton, segregation of proteins according to the size of their extracellular domains, and association of proteins with lipid rafts. Towards understanding the function of the IS, it is instructive to compare and contrast the supramolecular organization of proteins at the inhibitory and activating NK cell IS with that at the activating T cell IS. Finally, it is essential to develop new technologies for probing molecular recognition at cell surfaces. Imaging parameters other than fluorescence intensity, such as the lifetime of the fluorophore's excited state, could be used to report on protein environments.
Comment penser l’histoire environnementale de l’Éthiopie ? La question de l’environnement fait l’objet de réflexions de la part des historiens de ce pays depuis la fin des années 1960. Mais ils ont ...rarement adopté explicitement un cadre d’analyse en histoire environnementale, attentif à articuler l’étude des contraintes et des transformations de l’environnement avec celle, plus large, de la manière dont les sociétés s’approprient, façonnent et interprètent ce qui les entoure. Cette rematérialisation des dynamiques politiques, sociales et culturelles permet de revisiter l’histoire du continent africain. À ce titre, la place de l’Éthiopie est particulière car la colonisation européenne, qui a été la matrice de l’histoire environnementale de langue anglaise, n’a pas joué le même rôle que dans les autres pays. C’est une invitation à relativiser le moment colonial dans l’histoire environnementale de longue durée des sociétés africaines. Ce dossier, le premier de son genre, souhaite donc poser les jalons d’une histoire environnementale de l’Éthiopie qui est encore à construire, en s’appuyant sur une tradition savante attentive à la géographie et à l’histoire rurale, et sur quelques travaux pionniers plus récents. Les articles réunis ici, qu’ils viennent ou non d’historiens de l’environnement, interrogent donc tous un terrain à partir de l’environnement comme catégorie d’analyse. Du monde médiéval des seuils à l’invention contemporaine du patrimoine, se dessinent la diversité d’un territoire, des hauts plateaux chrétiens du Nord aux basses terres musulmanes de l’Est, mais aussi la continuité des rapports de pouvoir et de la violence qui se nouent autour de l’environnement.
The optimal post-remission therapy for patients with acute myeloblastic leukaemia remains controversial. Allogeneic bone marrow transplantation, autologous bone marrow transplantation, and ...consolidation chemotherapy are the major options. In order to evaluate their respective value the European Group for Bone Marrow Transplantation conducted a prospective registration study. Patients with newly diagnosed acute myeloblastic leukaemia were registered at the time of HLA-typing and intention to treat in case of presence or absence of an HLA-identical donor was recorded. 27/79 (34%) patients HLA-typed at diagnosis had an identical donor identified. The estimated survivals at 3 years from HLA-typing were 44% and 21% among patients with or without HLA-identical donor, respectively (P = 0.02). 22/26 (85%) patients for whom allogeneic bone marrow transplantation was intended were transplanted but only 15/47 (32%) patients for whom autologous bone marrow transplantation was intended were indeed transplanted (P < 0.001). The survival was 50%, 29% and 17% (P = 0.004) for patients treated with allogeneic bone marrow transplantation, autologous bone marrow transplantation, or chemotherapy, respectively. 40/68 patients HLA-typed in first complete remission had an HLA-identical donor. The estimated 3-year survival among patients typed in first remission with and without HLA-identical donors was 42% and 35% (n.s.), respectively. This technique of early patient registration illustrates the problems of patient selection during the course of the disease and might be used as a complement to randomized trials when comparing bone marrow transplantation and other treatment options.
