Elevated VIP and endotoxin plasma levels in human gram-negative septic shock

Vasoactive intestinal polypeptide (VIP) and endotoxin (lipopolysaccharides, LPS) were measured in plasma samples from 11 patients with bacteriologically verified meningococcal disease. Five patients suffered fulminant septicaemia, developed severe septic shock, and 2 died due to circulatory collapse. Initially, all 5 had levels of VIP above 4 pM and plasma endotoxin above 200 ng/liter. Five patients were diagnosed as meningitis and 1 as having meningococcaemia, all with a normal circulatory state. None of these 6 patients had initially levels of VIP above 2.5 pM or endotoxin levels above 25 ng/liter (P less than 0.001). A correlation existed between plasma endotoxin and VIP levels (r = 0.735, P = 0.01). Sequentially collected samples from 3 patients showed rapidly declining VIP levels after initiation of antibiotic and fluid treatment. These results are in agreement with previous animal experiments, suggesting that endotoxin directly or indirectly stimulates the VIP-ergic nervous system in the initial phase of gram-negative septic shock in man.     

Reversible phytochrome regulation influenced the severity of ozone-induced visible foliar injuries in Trifolium subterraneum L.

In Trifolium subterraneum, oxidative stress caused by ozone has been shown to result in more severe visible foliar injuries when plants were kept in dim broadband white light during the night (i.e. a long photoperiod) compared to darkness during the night (a short photoperiod). As phytochrome signalling is involved in photoperiod sensing, the effect of night-time red and far-red illumination on the ozone-induced response was studied. T. subterraneum plants were treated with ozone enriched air (70?ppb) for either 1?h for a single day or 6?h for three consecutive days. After the first ozone exposure, plants were separated into six night-time light regimes during the two subsequent nights (10?h?day, 14?h night): (1) darkness, (2) far-red light (FR), (3) a short night-break of red followed by far-red light during an otherwise dark night (R FR), (4) a short night-break of red, far-red and finally red light during an otherwise dark night (R FR R), (5) dim white light (L) and (6) red light (R). The treatments L and R resulted in significantly more severe ozone-induced visible foliar injuries relative to D and FR treatments, indicating a phytochrome-mediated response. The night-breaks resulted in a photoreversible and significantly different ozone response depending on the light quality of the last light interval (R FR or R FR R), supporting a photoreversible (between P_r and P_fr) phytochrome signalling response. Thus, in T. subterraneum, the outcome of oxidative stress due to ozone appears to depend on the photoperiod mediated by the night-time conformation of phytochrome.     

Binding of vasoactive intestinal polypeptide (VIP) by human blood monocytes: demonstration of specific binding sites

Vasoactive intestinal polypeptide (VIP) interaction with a 94% pure preparation of monocytes isolated from human peripheral blood was studied by direct binding technique using 3-[125I]tyrosyl-VIP as a tracer ligand. Scatchard analysis of binding data was compatible with two classes of binding sites, one with Kd = 0.25 nM and maximal binding capacity of 16 fmol/10(6) cells, and another one with Kd = 25 nM and maximal binding capacity of 180 fmol/10(6) cells. The binding was time-, temperature-, and pH-dependent and was saturable, reversible, and specific. This study has demonstrated that human monocytes have high affinity/low capacity as well as low affinity/high capacity binding sites for VIP. No specific VIP binding was found in pure preparations of human granulocytes, platelets or erythrocytes.     

Secretin—a new stress hormone?

The plasma concentration of secretin was measured during a 5-day military training course comprising prolonged physical exercise (35% of max O₂ uptake), severe caloric deficiency (approx. 35700 kJ/24 h) and sleep deprivation (only 2 h of sleep as a total during 5 days). 24 subjects were divided into 3 groups, one group was compensated for the caloric deficiency and another group was partly compensated for the sleep deprivation. The results showed that the fasting plasma secretin increased 3–6-fold (from 1.8–3.7 to 13.3–19.1 pmol/l) during the course with small differences in increase between the groups. Ingestion of a mixed meal reduced the fasting plasma secretin by about 40% during the course, while oral glucose reduced the plasma secretin to the concentrations found in the control experiment.The study shows that plasma secretin is increased when man is exposed to prolonged multifactorial stress. Additional food or sleep appears to have small influence on the fasting plasma secretin, but after giving a meal or oral glucose solution the plasma secretin decreases rapidly.     

The effect of sleep deprivation on the plasma levels of hormones during prolonged physical strain and calorie deficiency

The effect of sleep on the serum levels of hormones during prolonged heavy physical strain and calorie deficiency were investigated in 19 young men participating in a 5 day ranger training course with a calorie consumption of 35,000-50,000 kJ X 24 h-1, and a calorie intake of about 6,000 kJ X 24 h-1. The subjects were divided into two groups: the stress group (8 cadets) were allowed no organized sleep during the course, whereas the sleep group (9 cadets) had 3 h sleep each night. Small but significantly (p less than 0.01) higher serum levels were found in the sleep group compared to the stress group for cortisol, growth hormone and testosterone. No such differences were found for catecholamines, androstendione, dihydrotestosterone, LH, triiodothyronine and thyroxine. Androstendione and dihydrotestosterone decreased in parallel with testosterone (r = 0.5) during the course, changes which directly or indirectly seem to be due to decreased testicular secretion. The changes found during this investigation for the other hormones are similar to changes found during previous courses. LH showed only small variation during the course and cannot explain the decreased secretion from the testis or the difference between the two groups for testosterone. All hormones were normal within 23 days after the end of the course.     

Decreased serum levels of oestradiol, testosterone and prolactin during prolonged physical strain and sleep deprivation, and the influence of a high calorie diet

The changes in oestradiol, testosterone and prolactin, and the effects of a high calorie diet, were investigated in eleven young males cadets participating in a 5 days' ranger training course involving heavy and continuous physical activities with less than 1500 kcal . day-1 and almost without sleep. Prolactin decreased continuously during the first 24 h to 25% of precourse values. Testosterone decreased during the day time and reached below 25% of precourse values after 48 h. Oestradiol did not change during the first 48 h but then decreased to about 50% of precourse values. In conclusion, oestradiol, testosterone and prolactin are strongly reduced during prolonged strain. These changes were not reversed by a high calorie diet.     

Activity and swimming speed at time of first feeding of halibut (Hippoglossus hippoglossus) larvae

Atlantic halibut larvae show an increase in activity, together with a decrease in swimming speed during active periods, occurring from day 26 onwards, which corresponds approximately to 50% yolk absorption.     

The Edinburgh Mouse Atlas: using the CD

This paper provides a simple introduction to the reconstructions and data-handling tools stored on the Edinburgh Mouse Atlas CD, together with some of the ways in which the viewers and software can be used to understand mouse development and analyse data. The key aspect of the Mouse Atlas is that the underlying models are a complete representation of the histology, which has not been constrained to a particular interpretation. This means, for example, that the current anatomy domains can be further subdivided as required to any resolution up to the resolution of the models (2-7 microm). In the CD of the early embryos described here, virtually all tissues that can be usefully distinguished either by the histology or morphologically have been delineated.     

Behavioural correlates of phenotypic plasticity in mouthpart chemoreceptor numbers in locusts

Rearing locusts in an impoverished chemosensory environment leads to fewer chemoreceptors developing on the mouthparts and antennae as adults but the behavioural relevance of these changes remains unknown. To address this question, locusts were reared for the final two larval stadia on either a single, nutritionally near-optimal synthetic food ('plain' pretreatment), or a diet comprising two nutritionally complementary foods containing two added flavours ('mix' pretreatment). Insects reared on the 'mix' diet had a mean 20% more chemosensilla on the maxillary palps than those fed on the 'plain' diet. Following an equilibration period, when all newly moulted adults could feed on two nutritionally complementary foods, insects were food deprived for 2 or 6 h, and then given a test meal of a single balanced food at one of two dilutions whilst their behaviour was recorded. 'Mix'-pretreated locusts had a shorter latency to feed and were more likely to reject the test food upon first contact if deprived for only 2 h; but if they did take a meal it lasted longer and contained fewer pauses. Using sensilla number as a covariate removed the statistical significance of pretreatment regime, indicating that sensilla number, or some close correlate of it, can largely account for the variation in behaviour. This suggests that sensilla numbers are behaviourally relevant; particularly where locusts are not greatly food deprived and faced with marginally acceptable foods.