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While rotavirus is well established as a major cause of severe acute gastroenteritis in young children all over the world, our understanding of the mechanisms underlying the clinical symptoms largely remains unresolved. The clinical symptoms are not limited to life threatening diarrhoea and vomiting, but also include systemic effects, collectively called “sickness responses.” In this review we discuss recent progress in exploring the mechanisms of rotavirus-induced diarrhoea and vomiting, delayed gastric emptying, and sickness responses such as fever and abdominal pain.

Publisher Summary This chapter discusses the background knowledge about the enteric nervous system (ENS) as well as the role of ENS in secretory states of the small intestine. The chapter describes the anatomy and physiology of the ENS. A description of the experimental evidence for the involvement of ENS in secretory states of the gut, primarily in cholera toxin-induced secretion that is the most thoroughly investigated secretory state, is presented in the chapter. The chapter focuses on the involvement of ENS in rotavirus (RV) diarrhea. The involvement of the ENS in diarrhea pathophysiology opens up new potential sites of action for drugs in the treatment of intestinal secretory states. The chapter concludes with a discussion of the sites of action for the pharmacological treatment of diarrhea.

During the active phase of JET, an accurate measurement of absolute pressure in the range 10−1 to 103 mbar is needed for tritium gas accounting when the Neutral Injector cryopumps are regenerated. Pirani gauges which cover this pressure range are prone to drift and give an indication of pressure which is gas dependant. Capacitance manometer pressure gauges, a typical example of which is the MKS Baratron©, are well suited to the measurement of absolute pressure in this range. A system has been developed to remotely sense the capacitance of a Baratron head. The Baratron electronics is replaced by a circuit containing only passive, radiation resistant components. Cables up to 100m long connect the measurement head to detection electronics located outside the Torus Hall. Low resolution data at high sample rate is processed to give a reading with 12 bits of resolution at 1 reading per second.

The JET Neutral Beam Injection (NBI) system [ref.1] has routinely delivered beams with a peak neutral power density of >200MWm−2 at the tokamak port, the highest value achieved in any existing injection system. The power loading constraints due to the inefficiency of positive ion to neutral conversion, the collimation of the beam, and the loss of reionised particles are severe. The injectors therefore require cooling of all major components to allow pulse lengths in excess of 10 seconds. A comprehensive thermal instrumentation system with many unique features has been developed which has proved essential for the safe operation of the beamlines. Additionally, it had been used to determine the neutralisation efficiency, beam divergence, beam alignment and power injected into the tokamak plasma.

The First Tritium Experiment (FIE) on JET (ref. 1) used Neutral Beam Injection (NBI) not only to heat the plasma using 14 beams of energetic deuterium, but also to supply the tritium via the remaining two injectors which were specially modified for this purpose. This represents a significant advance in the technology of NBI and in this paper we describe the Tritium Gas Introduction System (TGIS), which was an essential feature of this development.

The effect of a diet containing triglycerides of different fatty acid composition on hepatic 7alpha-hydroxylation of cholesterol was studied. 7alpha-Hydroxylation of exogenous as well as endogenous cholesterol was significantly lower in the liver of rats fed trilinolein and triolein than in those fed tripalmitin and trierucin. The concentration of cytochrome P-450 in liver microsomes was significantly lower in the rats fed tripalmitin and trierucin than in those fed triolein and trilinolein. The inhibitory effect of triolein and trilinolein on 7alpha-hydroxylation of cholesterol and the stimulatory effect of these triglycerides on the concentration of cytochrome P-450 was not due to the small amounts of peroxides present in the unsaturated triglycerides. Thus addition of the antioxidant butylated hydroxyanisol did not change the general pattern with respect to 7alpha-hydroxylation and concentration of cytochrome P-450. However, a diet consisting of peroxidized linoleic acid further decreased 7alpha-hydroxylation of cholesterol. The difference between the effect obtained with triolein and trilinolein on the one hand and trierucin and tripalmitin on the other was observed also in experiments with lower concentrations of fat in the diet and in experiments with different lighting conditions and feeding patterns. The inverse relation between cytochrome P-450 and 7alpha-hydroxylation of cholesterol, as well as results obtained with substrates for mixed-function oxidation other than cholesterol suggest that most of the changes observed due to the different diets are specific for 7alpha-hydroxylation of cholesterol. The level of cholesterol 7alpha-hydroxylase activity was found to be better related to the degree of absorption of fat than to total amount of absorbed fat or degree of unsaturation of the fat. The results are discussed in relation to previous knowledge concerning mechanisms regulating biosynthesis of bile acid.