Transmembrane tumor necrosis factor is a potent inducer of colitis even in the absence of its secreted form

Tumor necrosis factor (TNF) is cleaved proteolytically from a 26-kilodalton transmembrane precursor protein into secreted 17-kilodalton monomers. Transmembrane (tm) and secreted trimeric TNF are biologically active and may mediate distinct activities. We assessed the consequences of a complete inhibition of TNF processing on the course of colitis in recombination activating gene (RAG)2 -/- mice on transfer of CD4 CD45RB hi T cells.

Interannual variation in land-use intensity enhances grassland multidiversity

Although temporal heterogeneity is a well-accepted driver of biodiversity, effects of interannual variation in land-use intensity (LUI) have not been addressed yet. Additionally, responses to land use can differ greatly among different organisms; therefore, overall effects of land-use on total local biodiversity are hardly known. To test for effects of LUI (quantified as the combined intensity of fertilization, grazing, and mowing) and interannual variation in LUI (SD in LUI across time), we introduce a unique measure of whole-ecosystem biodiversity, multidiversity. This synthesizes individual diversity measures across up to 49 taxonomic groups of plants, animals, fungi, and bacteria from 150 grasslands. Multidiversity declined with increasing LUI among grasslands, particularly for rarer species and aboveground organisms, whereas common species and belowground groups were less sensitive. However, a high level of interannual variation in LUI increased overall multidiversity at low LUI and was even more beneficial for rarer species because it slowed the rate at which the multidiversity of rare species declined with increasing LUI. In more intensively managed grasslands, the diversity of rarer species was, on average, 18% of the maximum diversity across all grasslands when LUI was static over time but increased to 31% of the maximum when LUI changed maximally over time. In addition to decreasing overall LUI, we suggest varying LUI across years as a complementary strategy to promote biodiversity conservation.

Subklinische Hypothyreose: Risiken, aktuelle Empfehlungen und randomisierte Studie in der Schweiz

Quintessenz: • Die subklinische Hypothyreose ist definiert durch erhöhte TSH und normwertige ThyroxinSpiegel; sie kommt bei älteren Patienten häufig vor (10–15%). • Daten aus Beobachtungsstudien zeigen einen möglichen Zusammenhang zwischen der subklinischen Hypothyreose und verschiedenen Krankheitsbildern wie kardiovaskulären Erkrankungen, Muskelbeschwerden sowie depressiven oder kognitiven Störungen. • Die Indikation zur Thyroxin Substitution bei subklinischer Hypothyreose ist derzeit noch nicht klar, was sich in grossen Unterschieden bezüglich Therapie zwischen verschiedenen Ländern niederschlägt. Es zeigt sich jedoch eine Zunahme der ThyroxinVerschreibungen. • Die Teilnahme an der randomisierten TRUST Studie ist die derzeit beste «Behandlungsoption» für ältere Patienten mit subklinischer Hypothyreose.