Type VIII collagen

Type VIII collagen is a product of endothelial cells, keratinocytes, mast cells, microvascular endothelial cells and some tumour cells. It is also present in a variety of extracellular matrices as diverse as sclera, skin and glomerulus. Type VIII molecules have a proposed chain composition of [alpha 1(VIII)2 alpha 2(VIII)]. While the function of collagen type VIII is uncertain recent work has highlighted the importance of this collagen in the vasculature. Particularly significant may be its up-regulation in smooth muscle cell migration and potential role in maintaining the smooth muscle cell phenotype. It is interesting to speculate that this collagen may provide a substratum for a variety of cells and facilitate movement of endothelial cells in angiogenesis, smooth muscle cells in intimal invasion and myofibroblasts in fibrotic conditions.     

Synchrotron radiation for long wavelength spectroscopy

A fundamental radiometric measurement has been carried out in the spectral region 1–140 cm^?1 which demonstrates the higher brightness of the synchrotron radiation source at Daresbury Laboratory over a high pressure mercury arc lamp source. Comparison of the output powers from the SRS and the mercury lamp revealed that the SRS has a particular advantage in the region where the wavelength of the emitted photon becomes very longer. The gain factor of the SRS at 10 cm^?1 was at least 10 times of the mercury lamp at a storage ring current of about 90 mA. A single period wiggler is considered to be a favorable device which will provide a higher level of photon fluxes from an electron storage ring in the long wavelength region.     

Vasoactive intestinal peptide stimulates a cAMP-mediated Cl- current in avian salt gland cells

VIP plays an integral role in both protein and fluid secretion in many exocrine glands. By employing the perforated patch-clamp whole-cell recording technique we investigated the effects of VIP on membrane potential and transmembrane currents in avian exocrine salt gland cells. Prior to application of VIP, salt gland cells had a resting membrane potential close to -45 mV. When challenged with VIP (1-100 nM) a sustained depolarization to ECl- was induced which was mimicked by the application of cell-permeable cAMP analogues or forskolin (1 microM). By employing the voltage-clamp recording configuration a sustained increase in current was observed with a reversal potential which approximated ECl-. Ionic substitution experiments confirmed that the current was a Cl- conductance which was inhibited by the Cl- channel blockers flufenamic acid and niflumic acid and by the inhibitory cAMP isomer, adenosine-3',5'-cyclic monophosphothioate, Rp-isomer. Based on this, and the fact that the kinetic properties of the Cl- current activated by VIP are similar to those activated by cAMP, we propose that VIP-receptor interaction results in the activation of a cAMP-dependent Cl- current.     

The contribution of remote monitoring to the development of IBC

The author describes an application pilot experiment being carried out under the European Communities' RACE programme. The experiment centres on the electronic security industry, in particular the remote monitoring of alarm signals. The aim of the project is to reduce the waste of resources caused by the high number of `false' alarm calls and to introduce the users of remote signalling systems to the benefits of improving communications technology. The author summaries the problem and presents a scenario for introducing the users of basic signalling systems to a wider variety of potential services that can be provided in an integrated broadband communications environment     

Electricity transmission pricing: Contracts must reflect costs

Pricing of transmission services in the open-access networks required for competition must take into account the three main costs of providing transmission services: costs of building capacity (including sunk costs); costs of marginal losses; and costs of congestion.