Microbiology: eukaryotic diversity in Spain's River of Fire

The Rio Tinto, known by the Phoenicians as 'Ur-yero', or 'River of Fire', because of its deep red colour and high acidity, flows through the world's largest pyritic belt in southwestern Spain. Surprisingly, eukaryotic microbes are the principal contributors of biomass in this hostile river, which has a pH of 2 and contains much higher concentrations of heavy metals than are typically found in fresh waters. Here we show that the Rio Tinto shows an unexpected degree of eukaryotic diversity and includes new lineages that we have identified by sequence analysis of genes encoding small-subunit ribosomal RNAs. The diversity of these eukaryotes is much greater than that of prokaryotes, whose metabolism is responsible for the extreme environment.     

The auroral footprint of Enceladus on Saturn

Although there are substantial differences between the magnetospheres of Jupiter and Saturn, it has been suggested that cryovolcanic activity at Enceladus could lead to electrodynamic coupling between Enceladus and Saturn like that which links Jupiter with Io, Europa and Ganymede. Powerful field-aligned electron beams associated with the Io-Jupiter coupling, for example, create an auroral footprint in Jupiter's ionosphere. Auroral ultraviolet emission associated with Enceladus-Saturn coupling is anticipated to be just a few tenths of a kilorayleigh (ref. 12), about an order of magnitude dimmer than Io's footprint and below the observable threshold, consistent with its non-detection. Here we report the detection of magnetic-field-aligned ion and electron beams (offset several moon radii downstream from Enceladus) with sufficient power to stimulate detectable aurora, and the subsequent discovery of Enceladus-associated aurora in a few per cent of the scans of the moon's footprint. The footprint varies in emission magnitude more than can plausibly be explained by changes in magnetospheric parameters--and as such is probably indicative of variable plume activity.     

α-Particle track autoradiography for localization of a211At-astatinated drug

Cellular and Molecular Life Sciences - A potential endoradiotherapeutic drug, 6-211At-astato-2-methyl-1,4-naphthoquinol bis (diphosphate salt), incorporating the α-emitting radio-halogen...     

A hapten-specific chimaeric IgE antibody with human physiological effector function

Immunoglobulin E (IgE) has a central role in allergic reactions although it rarely exceeds 5 micrograms ml-1 even in the serum of severely allergic individuals. Both mast cells and basophils possess receptors which bind the Fc portion of IgE with high affinity; crosslinking of membrane-bound IgE by allergen results in degranulation of the cell and release of a variety of pharmacologically active mediator including histamine. Myeloma IgE has been successfully used to block the skin sensitizing activity of allergic sera; however, human myeloma IgE is clearly in limited supply. The emergence of techniques allowing the stable introduction of immunoglobulin gene DNA into myeloma cells has allowed us to construct a mouse cell line that secretes a chimaeric IgE, lambda 1 antibody whose heavy chain is composed of a human C epsilon constant region fused to a mouse variable (VH) region. This chimaeric IgE is specific for the hapten 4-hydroxy-3-nitro-phenacetyl (NP) and can, when crosslinked by antigen, trigger the degranulation of human basophils. When not crosslinked, however, the chimaeric IgE can prevent the passive sensitization of these cells by sera from allergic subjects.     

Body temperatures of lambs and their mothers measured by radio-telemetry during parturition

Using temperature-sensitive radio-telemeters chronically implanted in the abdomens of 8 fetal lambs and their mothers, we measured body temperature changes induced by parturition. Maternal body temperature rose at 0.70±0.06 °C/hour (mean±SEM) in the final stages of labour. Fetal body temperature also rose, but at a significantly lower rate, 0.45±0.06 °C/hour (p<0.05). The fetus appears to be protected from excessive hyperthermia during the birth process.