Uncoupling of the disorder of carbohydrate metabolism from fat metabolism in experimentally-produced diabetes in baboons(Papio ursinus)

Résumé Après ablation de la glande pituitaire, ledérèglement du du métabolisme des hydrates de carbone persiste, tandis que l'intense lipémie est abolie. L'administration de la cortisone aux babouins pancréas- et hypophysectomisés privés d'insuline, rétablit la lipémie mais non la cétonémie.Le dérèglement du métabolisme des hydrates de carbone dans les babouins diabétiques peut être dissocié de celui des lipides par un traitement approprié des glandes endocrines.La cétonémie des babouins pancréas- et hypophysectomisés, contrairement à la lipémie, n'est pas rétabli par l'administration de la cortisone, thyroxin ou par une combinaison de ces hormones.     

The adult Drosophila posterior midgut is maintained by pluripotent stem cells

Vertebrate and invertebrate digestive systems show extensive similarities in their development, cellular makeup and genetic control. The Drosophila midgut is typical: enterocytes make up the majority of the intestinal epithelial monolayer, but are interspersed with hormone-producing enteroendocrine cells. Human (and mouse) intestinal cells are continuously replenished by stem cells, the misregulation of which may underlie some common digestive diseases and cancer. In contrast, stem cells have not been described in the intestines of flies, and Drosophila intestinal cells have been thought to be relatively stable. Here we use lineage labelling to show that adult Drosophila posterior midgut cells are continuously replenished by a distinctive population of intestinal stem cells (ISCs). As in vertebrates, ISCs are multipotent, and Notch signalling is required to produce an appropriate fraction of enteroendocrine cells. Notch is also required for the differentiation of ISC daughter cells, a role that has not been addressed in vertebrates. Unlike previously characterized stem cells, which reside in niches containing a specific partner stromal cell, ISCs adjoin only the basement membrane, differentiated enterocytes and their most recent daughters. The identification of Drosophila intestinal stem cells with striking similarities to their vertebrate counterparts will facilitate the genetic analysis of normal and abnormal intestinal function.     

Spider toxins activate the capsaicin receptor to produce inflammatory pain

Bites and stings from venomous creatures can produce pain and inflammation as part of their defensive strategy to ward off predators or competitors. Molecules accounting for lethal effects of venoms have been extensively characterized, but less is known about the mechanisms by which they produce pain. Venoms from spiders, snakes, cone snails or scorpions contain a pharmacopoeia of peptide toxins that block receptor or channel activation as a means of producing shock, paralysis or death. We examined whether these venoms also contain toxins that activate (rather than inhibit) excitatory channels on somatosensory neurons to produce a noxious sensation in mammals. Here we show that venom from a tarantula that is native to the West Indies contains three inhibitor cysteine knot (ICK) peptides that target the capsaicin receptor (TRPV1), an excitatory channel expressed by sensory neurons of the pain pathway. In contrast with the predominant role of ICK toxins as channel inhibitors, these previously unknown 'vanillotoxins' function as TRPV1 agonists, providing new tools for understanding mechanisms of TRP channel gating. Some vanillotoxins also inhibit voltage-gated potassium channels, supporting potential similarities between TRP and voltage-gated channel structures. TRP channels can now be included among the targets of peptide toxins, showing that animals, like plants (for example, chilli peppers), avert predators by activating TRP channels on sensory nerve fibres to elicit pain and inflammation.     

Trends in A8 migration to the UK during the recession

A substantial proportion of contemporary migration flows to the UK are made by nationals from countries which have recently joined the EU. The nature of A8 migration during the recession is examined in this paper, mainly using data from the Worker Registration Scheme. The recession has seen a decline in new A8 migrants entering the UK labour market, but the decline has been sectorally uneven, with demand for migrant labour being most persistent in the agricultural sector, raising questions about why this part of the UK economy is so different.     

抽出处理措施的有效性评价

应用经过拟合的模型,对实例中实施的抽出水处理措施的有效性作了数值模拟分析,结果表明,在模拟时段内场地区碳岩含水层中ＴＣＥ污染羽状体的分布范围及其浓度均有比较明显的减小,去污效率比较理想。已由抽水试验证实,其有利因素之一就是污染含水层介质具有较强的水力传导性,鉴于系统的不确定性,应对抽出处理方案进行多阶段设计。     

Tycho brahe in china: the Jesuit mission to Peking and the iconography of European instrument-making processes

In the late 1660s, Ferdinand Verbiest, a Flemish Jesuit missionary in Peking, was instructed to re-equip the Imperial Observatory. The new instruments which he caused to be built were modelled neither upon contemporary European prototypes, nor those of traditional Chinese astronomy, but on the pieces in Tycho Brahe's Mechanica, of eighty years before. The Chinese instruments were lavishly illustrated, moreover, in 105 woodcuts that contained detailed representations of their processes of construction. It is argued that these illustrations not only give us valuable insights into what the technical Jesuits did in Peking, but show how sixteenth- and seventeenth-century European craftsmen constructed their instruments, for while the location was Oriental, the technology was Western. They can also give important insights into how Tycho's prototypes had been built, and provide us with useful information regarding European instrument-making technology.     

Biomaterials in the nano-era

This article is a brief summary of my plenary talk at the World Biomaterials Congress in Chengdu, Sichuan, China, June 1-5, 2012. It highlights the trend to design and develop biomaterial implants and devices that are more compact and more efficient, as they ＂shrink＂ from the macro- to the micro- and down to the nano-scale.