46 research outputs found
Environment-Controlled Postsynthetic Modifications of Iron Formate Frameworks
New hybrid iron-formate
perovskites have been obtained in high-pressure reactions. Apart from the
pressure range, also the liquid environment of the sample regulates the course
of transformations. Formate α-DmaFe2+Fe3+For6, when
compressed in oil and in isopropanol at 1.40 GPa, transforms to a new phase γ, different than that phase β obtained at
low-temperature. In glycerol
phase α can be compressed to 1.40 GPa, but then reacts to DmaFe2+For3,
with all Fe(III) cations reduced, surrounded by amorphous iron
formate devoid of Dma
cations. Another
mixed-valence framework Dma3[Fe2+3Fe3+For6]2·CO2,
can be produced from phase α incubated in methanol and ethanol at 1.15 GPa. These
pressure-induced environment-sensitive modifications have been rationalised by
the volume effects involving the oxidation states of Fe(II) and
Fe(III), their high- and low-spin states as well as the properties of pressure transmitting media. The topochemical
redox reactions controlled by pressure and the liquid environment offer new
highly efficient, safe and environment-friendly reactions leading to new advanced
materials and their post-synthesise modifications.</b
CD8+ T cells from patients with acute multiple sclerosis display selective increase of adhesiveness in brain venules: a critical role for P-selectin glycoprotein ligand-1.
ultiple sclerosis (MS) is considered an autoimmune inflammatory disease of the central nervous system. Under physiologic conditions, we compared the adhesiveness of CD4+ and CD8+ lymphocytes from nontreated patients with acute, relapsing-remitting multiple sclerosis (RRMS) and from healthy donors. We show that in patients with RRMS CD8+, but not with RRMS CD4+, T cells display increased rolling and arrest in inflamed murine brain venules. Moreover, CD8+, but not CD4+, lymphocytes from MS patients show increased rolling on P-selectin in vitro. Anti-P-selectin glycoprotein ligand-1 (PSGL-1) antibodies dramatically block the recruitment of CD8+ cells in brain vessels of patients with MS, suggesting that PSGL-1 represents a novel pharmaceutical target that may be exploited to block the selective entrance of CD8+ cells during early inflammation. Vascular cell adhesion molecule-1 (VCAM-1), but not PSGL-1, is critical for the adhesion of CD4+ cells in MS patients, highlighting a fundamental dichotomy in the mechanisms governing the recruitment of lymphocyte subsets in RRMS. Importantly, 7-color fluorescence-activated cell sorter (FACS) analysis, together with functional data, indicates that a large fraction of CD8+ cells from MS patients display the characteristics of memory-effector phenotype. In conclusion, our results show that CD8+, but not CD4+, T cells from patients with RRMS in the acute phase of the disease display increased ability to be recruited in inflamed brain venules
CD8+ T cells from patients with acute multiple sclerosis display selective increase of adhesiveness in brain venules: a critical role for P-selectin glycoprotein ligand-1
Multiple sclerosis (MS) is considered an autoimmune inflammatory disease of the central nervous system. Under physiologic conditions, we compared the adhesiveness of CD4+ and CD8+ lymphocytes from nontreated patients with acute, relapsing-remitting multiple sclerosis (RRMS) and from healthy donors. We show that in patients with RRMS CD8+, but not with RRMS CD4+, T cells display increased rolling and arrest in inflamed murine brain venules. Moreover, CD8+, but not CD4+, lymphocytes from MS patients show increased rolling on P-selectin in vitro. Anti-P-selectin glycoprotein ligand-1 (PSGL-1) antibodies dramatically block the recruitment of CD8+ cells in brain vessels of patients with MS, suggesting that PSGL-1 represents a novel pharmaceutical target that may be exploited to block the selective entrance of CD8+ cells during early inflammation. Vascular cell adhesion molecule-1 (VCAM-1), but not PSGL-1, is critical for the adhesion of CD4+ cells in MS patients, highlighting a fundamental dichotomy in the mechanisms governing the recruitment of lymphocyte subsets in RRMS. Importantly, 7-color fluorescence-activated cell sorter (FACS) analysis, together with functional data, indicates that a large fraction of CD8+ cells from MS patients display the characteristics of memory-effector phenotype. In conclusion, our results show that CD8+, but not CD4+, T cells from patients with RRMS in the acute phase of the disease display increased ability to be recruited in inflamed brain venules