Temperature dependent CO2 behavior in microporous 1-D channels of a metal-organic framework with multiple interaction sites

The MOF with the encapsulated CO2 molecule shows that the CO2 molecule is ligated to the unsaturated Cu(II) sites in the cage using its Lewis basic oxygen atom via an angular eta(1)-(O-A) coordination mode and also interacts with Lewis basic nitrogen atoms of the tetrazole ligands using its Lewis acidic carbon atom. Temperature dependent structure analyses indicate the simultaneous weakening of both interactions as temperature increases. Infrared spectroscopy of the MOF confirmed that the CO2 interaction with the framework is temperature dependent. The strength of the interaction is correlated to the separation of the two bending peaks of the bound CO2 rather than the frequency shift of the asymmetric stretching peak from that of free CO2. The encapsulated CO2 in the cage is weakly interacting with the framework at around ambient temperatures and can have proper orientation for wiggling out of the cage through the narrow portals so that the reversible uptake can take place. On the other hand, the CO2 in the cage is restrained at a specific orientation at 195 K since it interacts with the framework strong enough using the multiple interaction sites so that adsorption process is slightly restricted and desorption process is almost clogged.ope

Mesodermal Progenitor Cells (MPCs) Differentiate into Mesenchymal Stromal Cells (MSCs) by Activation of Wnt5/Calmodulin Signalling Pathway

Mesenchymal Stromal Cells (MSCs) remain poorly characterized because of the absence of manifest physical, phenotypic, and functional properties in cultured cell populations. Despite considerable research on MSCs and their clinical application, the biology of these cells is not fully clarified and data on signalling activation during mesenchymal differentiation and proliferation are controversial. The role of Wnt pathways is still debated, partly due to culture heterogeneity and methodological inconsistencies. Recently, we described a new bone marrow cell population isolated from MSC cultures that we named Mesodermal Progenitor Cells (MPCs) for their mesenchymal and endothelial differentiation potential. An optimized culture method allowed the isolation from human adult bone marrow of a highly pure population of MPCs (more than 97%), that showed the distinctive SSEA-4+CD105+CD90(neg) phenotype and not expressing MSCA-1 antigen. Under these selective culture conditions the percentage of MSCs (SSEA-4(neg)CD105+CD90(bright) and MSCA-1+), in the primary cultures, resulted lower than 2%.We demonstrate that MPCs differentiate to MSCs through an SSEA-4+CD105+CD90(bright) early intermediate precursor. Differentiation paralleled the activation of Wnt5/Calmodulin signalling by autocrine/paracrine intense secretion of Wnt5a and Wnt5b (p<0.05 vs uncondictioned media), which was later silenced in late MSCs (SSEA-4(neg)). We found the inhibition of this pathway by calmidazolium chloride specifically blocked mesenchymal induction (ID₅₀ =  0.5 µM, p<0.01), while endothelial differentiation was unaffected.The present study describes two different putative progenitors (early and late MSCs) that, together with already described MPCs, could be co-isolated and expanded in different percentages depending on the culture conditions. These results suggest that some modifications to the widely accepted MSC nomenclature are required

Mapping human dispersals into the Horn of Africa from Arabian Ice Age refugia using mitogenomes

Rare mitochondrial lineages with relict distributions can sometimes be disproportionately informative about deep events in human prehistory. We have studied one such lineage, haplogroup R0a, which uniquely is most frequent in Arabia and the Horn of Africa, but is distributed much more widely, from Europe to India. We conclude that: (1) the lineage ancestral to R0a is more ancient than previously thought, with a relict distribution across the Mediterranean/Southwest Asia; (2) R0a has a much deeper presence in Arabia than previously thought, highlighting the role of at least one Pleistocene glacial refugium, perhaps on the Red Sea plains; (3) the main episode of dispersal into Eastern Africa, at least concerning maternal lineages, was at the end of the Late Glacial, due to major expansions from one or more refugia in Arabia; (4) there was likely a minor Late Glacial/early postglacial dispersal from Arabia through the Levant and into Europe, possibly alongside other lineages from a Levantine refugium; and (5) the presence of R0a in Southwest Arabia in the Holocene at the nexus of a trading network that developed after ~3 ka between Africa and the Indian Ocean led to some gene flow even further afield, into Iran, Pakistan and India

Cortical injury in multiple sclerosis; the role of the immune system

The easily identifiable, ubiquitous demyelination and neuronal damage that occurs within the cerebral white matter of patients with multiple sclerosis (MS) has been the subject of extensive study. Accordingly, MS has historically been described as a disease of the white matter. Recently, the cerebral cortex (gray matter) of patients with MS has been recognized as an additional and major site of disease pathogenesis. This acknowledgement of cortical tissue damage is due, in part, to more powerful MRI that allows detection of such injury and to focused neuropathology-based investigations. Cortical tissue damage has been associated with inflammation that is less pronounced to that which is associated with damage in the white matter. There is, however, emerging evidence that suggests cortical damage can be closely associated with robust inflammation not only in the parenchyma, but also in the neighboring meninges. This manuscript will highlight the current knowledge of inflammation associated with cortical tissue injury. Historical literature along with contemporary work that focuses on both the absence and presence of inflammation in the cerebral cortex and in the cerebral meninges will be reviewed

Y Chromosome Lineages in Men of West African Descent

The early African experience in the Americas is marked by the transatlantic slave trade from ∼1619 to 1850 and the rise of the plantation system. The origins of enslaved Africans were largely dependent on European preferences as well as the availability of potential laborers within Africa. Rice production was a key industry of many colonial South Carolina low country plantations. Accordingly, rice plantations owners within South Carolina often requested enslaved Africans from the so-called “Grain Coast” of western Africa (Senegal to Sierra Leone). Studies on the African origins of the enslaved within other regions of the Americas have been limited. To address the issue of origins of people of African descent within the Americas and understand more about the genetic heterogeneity present within Africa and the African Diaspora, we typed Y chromosome specific markers in 1,319 men consisting of 508 west and central Africans (from 12 populations), 188 Caribbeans (from 2 islands), 532 African Americans (AAs from Washington, DC and Columbia, SC), and 91 European Americans. Principal component and admixture analyses provide support for significant Grain Coast ancestry among African American men in South Carolina. AA men from DC and the Caribbean showed a closer affinity to populations from the Bight of Biafra. Furthermore, 30–40% of the paternal lineages in African descent populations in the Americas are of European ancestry. Diverse west African ancestries and sex-biased gene flow from EAs has contributed greatly to the genetic heterogeneity of African populations throughout the Americas and has significant implications for gene mapping efforts in these populations

Chimerism and outcomes after allogeneic hematopoietic cell transplantation following nonmyeloablative conditioning

Allogeneic hematopoietic cell transplantation ( HCT) following nonmyeloablative conditioning has been extensively evaluated in patients with hematologic malignancies who are ineligible for conventional HCT because of age or medical comorbidities. Nonmyeloablative regimens have led to an initial state of mixed hematopoietic chimerism defined as coexistence of donor- and host-derived hematopoiesis. While nonmyeloablative regimens have been associated with reduced regimen-related toxicities in comparison with conventional myeloablative conditioning, graft rejection, graft-versus-host disease ( GVHD), and disease progression have remained significant challenges. In this article, after briefly introducing current techniques for chimerism assessment, we describe factors affecting donor chimerism levels after nonmyeloablative conditioning, and then review data suggesting that chimerism assessment early after HCT might help identify patients at risk for graft rejection, GVHD and relapse/progression. Finally, we discuss how these observations have opened the way to further research protocols evaluating manipulation of postgrafting immunosuppression, and/or infusion of donor immune cells