Individual cell types in C. elegans age differently and activate distinct cell-protective responses

Aging is characterized by a global decline in physiological function. However, by constructing a complete single-cell gene expression atlas, we find that Caenorhabditis elegans aging is not random in nature but instead is characterized by coordinated changes in functionally related metabolic, proteostasis, and stress-response genes in a cell-type-specific fashion, with downregulation of energy metabolism being the only nearly universal change. Similarly, the rates at which cells age differ significantly between cell types. In some cell types, aging is characterized by an increase in cell-to-cell variance, whereas in others, variance actually decreases. Remarkably, multiple resilience-enhancing transcription factors known to extend lifespan are activated across many cell types with age; we discovered new longevity candidates, such as GEI-3, among these. Together, our findings suggest that cells do not age passively but instead react strongly, and individualistically, to events that occur during aging. This atlas can be queried through a public interface.

A low-temperature neutron diffraction study of Mn12-acetate

In the low-temperature region, where the dodecanuclear mixed-valence manganese carboxylate hexadecaacetatotetraaquadodecaoxododecamanganese bis(acetic acid) tetrahydrate, [Mn(12)O(12)(C(2)D(3)O(2))(16)(H(2)O)(4)].2C(2)HD(3)O(2).4H(2)O, displays unusual magnetic properties, its structure is similar to that previously determined at room temperature [Lis (1980). Acta Cryst. B36, 2042-2046], differing only by a small change in the configuration of one of the coordinated acetate groups, related to the formation of additional hydrogen bonds, and by the orientation of the methyl groups. Since most of the magnetization density of this system resides on the Mn atoms, the consequences of these rearrangements for the magnetic properties of the compound are small.

The changing nature of conflict and famine vulnerability: the case of livestock raiding in Turkana District, Kenya

The context of famine in Turkana has changed in recent years as the role played by livestock raiding in contributing to famine has increased. External responses to famine in Turkana have largely been drought driven, for example, food assistance and livestock restocking programmers, which have failed to meet the real needs of herders. The role of armed conflict in the form of raiding has been overlooked as a common feature of societies facing famine and food insecurity. The traditional livelihood-enhancing functions of livestock raiding are contrasted with the more predatory forms common today. The direct impact of raiding on livelihood security can be devastating, while the threat of raids and measures taken to cope with this uncertainty undermine herders' livelihood strategies. Self-imposed restrictions on mobility negatively affect the vegetation of both grazed and ungrazed pastures and restrict the available survival strategies. Predatory raiding leads to a collapse in the moral economy. Some implications of this for relief and development policy are considered, including approaches to conflict resolution.

Adhesion molecules on murine brain microvascular endothelial cells: expression and regulation of ICAM-1 and Lgp 55

The mechanisms for the initiation of immune reactions in the central nervous system are poorly understood. In this report, we describe the presence of intercellular adhesion molecule-1 (ICAM-1) and Lgp 55 (suggested mouse homologue of human intercellular adhesion molecule-2, ICAM-2) on the surface of brain microvessel endothelium (EN) cells and show in vitro induction of ICAM-1 molecules on EN cells with pro-inflammatory cytokines. ICAM-1 expression was detected using flow cytometry analysis with biotinylated anti-ICAM-1 antibody (YN1/1.7.4). Lgp 55 expression was characterized using PA3 monoclonal antibody. According to our results, 30-40% of the non-activated brain EN cells expressed ICAM-1 and 15-20% expressed Lgp 55 molecules. The ICAM-1 molecule expression was increased after the activation of the cells with recombinant murine gamma interferon (IFN-gamma), tumor necrosis factor (TNF-alpha), and interleukin-1 alpha (IL1-alpha) in a dose-dependent manner. The increased ICAM-1 expression was detected as early as 2 h following the cytokine treatment and reached its maximum after 24 h. Transforming growth factor-beta (TGF-beta) did not influence the expression of ICAM-1 molecule. Lgp 55 molecule does not seem to be regulated by pro-inflammatory cytokines. ICAM-1 and Lgp 55 expression was found to be polarized on the luminal surface of EN by confocal laser microscopy suggesting accessibility for leukocytes. Inducible ICAM-1 expression may play a critical role in formation of inflammatory reactions inside the central nervous system.