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In syncytial embryos nuclei undergo cycles of division and rearrangement within a common cytoplasm. It is presently unclear to what degree and how the nuclear array maintains positional order in the face of rapid cell divisions. Here we establish a quantitative assay, based on image processing, for analysing the dynamics of the nuclear array. By tracking nuclear trajectories in Drosophila melanogaster embryos, we are able to define and evaluate local and time-dependent measures for the level of geometrical order in the array. We find that after division, order is re-established in a biphasic manner, indicating the competition of different ordering processes. Using mutants and drug injections, we show that the order of the nuclear array depends on cytoskeletal networks organised by centrosomes. While both f-actin and microtubules are required for re-establishing order after mitosis, only f-actin is required to maintain the stability of this arrangement. Furthermore, f-actin function relies on myosin-independent non-contractile filaments that suppress individual nuclear mobility, whereas microtubules promote mobility and attract adjacent nuclei. Actin caps are shown to act to prevent nuclear incorporation into adjacent microtubule baskets. Our data demonstrate that two principal ordering mechanisms thus simultaneously contribute: (1) a passive crowding mechanism in which nuclei and actin caps act as spacers and (2) an active self-organisation mechanism based on a microtubule network.

Background: Inflammatory bowel disease (IBD), a paradigm of chronic illness, requires for its safe clinical management ready access to complete information, not always possible using paper records., Aim: To develop an IBD database (DB) for both individual patient management and collating information across centres., Methods: Access® based, with a minimum dataset., Results: Prospectively collected data for 11,432 patients from 21 centres. PROFILE DIAGNOSIS: Ulcerative colitis (UC) 56%, Crohn's disease (CD) 40%, indeterminate colitis 4%. M:F ratio: UC 1.08:1, CD 0.72:1. Median age at diagnosis: UC 39, CD 30 years. Operated: UC 16%, CD 47%. Thiopurine use: UC 16%, CD 29%. IBD related mortality: 0.74%., Discussion: A snapshot of this large IBD cohort shows the disease profile across the UK is similar to other large series. Unexpected gaps, sometimes large emerged (e.g. data on smoking and immunosuppression) highlighting the need for clear definition, consistency and completeness of data collection. Clinical management is made easier by the 'at a glance' summary, automated clinic letters, and facility for monitoring and audit, but the time required limited its 'real-time' use., Conclusion: Our experience shows it is possible to collect data from centres across the country which truly reflects clinical practice. We have learned as much from the process itself as from the data, principally, information needs to be well defined, validated at entry, and updated at every visit, a time consuming sequence which we had underestimated. Our lessons learned may help inform the development of a national database, and support national IBD standards and audit., (Copyright © 2010 European Crohn's and Colitis Organisation. Published by Elsevier B.V. All rights reserved.)

Oxyntomodulin is derived from proglucagon processing in the intestine and the central nervous system. To date, no role in the central nervous system has been demonstrated. We report here that oxyntomodulin inhibits refeeding when injected intracerebroventricularly and into the hypothalamic paraventricular nucleus of 24-h fasted rats [intracerebroventricularly and into the paraventricular nucleus, 1 h, oxyntomodulin (1 nmol), 3.1 +/- 0.5 g; saline, 6.2 +/- 0.4 g; P < 0.005]. In addition, oxyntomodulin inhibits food intake in nonfasted rats injected at the onset of the dark phase (intracerebroventricularly, 1 h: oxyntomodulin, 3 nmol, 1.1 +/- 0.19 g vs. saline, 2.3 +/- 0.2 g; P < 0.05). This effect of oxyntomodulin on feeding is of a similar time course and magnitude as that of an equimolar dose of glucagon-like peptide-1. Other proglucagon-derived products investigated [glucagon, glicentin (intracerebroventricularly, 3 nmol; into the paraventricular nucleus, 1 nmol), and spacer peptide-1 (intracerebroventricularly and into the paraventricular nucleus, 3 nmol)] had no effect on feeding at any time point examined. The anorectic effect of oxyntomodulin (intracerebroventricularly, 3 nmol; into the paraventricular nucleus, 1 nmol) was blocked when it was coadministered with the glucagon-like peptide-1 receptor antagonist, exendin-(9-39) (intracerebroventricularly, 100 nmol; into the paraventricular nucleus, 10 nmol). However, oxyntomodulin has a lower affinity for the glucagon-like peptide-1 receptor compared with glucagon-like peptide-1 (IC(50): oxyntomodulin, 8.2 nM; glucagon-like peptide-1, 0.16 nM). One explanation for this is that there might be an oxyntomodulin receptor to which exendin-(9-39) can also bind and act as an antagonist.

Plasma concentrations of neuropeptide Y (NPY) were measured in pregnant ewes and their fetuses under basal conditions and in response to acute hypoxemia during late gestation. The effects of fetal treatment with dexamethasone on these NPY responses were also examined. Under general anesthesia, 10 Welsh Mountain ewes and their fetuses were chronically instrumented between 117-120 days gestation (dGA; term is approximately 145 dGA) with vascular and amniotic catheters, and an ultrasonic probe around a femoral artery of each fetus. At 124 dGA, five fetuses were continuously infused i.v. with dexamethasone for 48 h at a rate of 1.73 +/- 0.16 microg x kg(-1) x h(-1) while the remaining five fetuses received vehicle at the same rate. At 126 dGA, 45 h from the onset of either infusion, 1 h of materno-fetal hypoxemia was induced by reducing maternal FiO2. During normoxia, maternal plasma NPY concentrations were three times those measured in fetal plasma in both groups. During hypoxemia, PaO2 fell to similar levels in the control and dexamethasone-treated groups in both mothers and fetuses. In control animals, there was a significant increase in the NPY concentration in fetal, but not maternal, plasma during hypoxemia. Fetal treatment with dexamethasone significantly enhanced the fetal NPY response to acute hypoxemia but had no effects on basal NPY levels in the fetal or maternal plasma or on the maternal response to acute hypoxemia. These data show: 1) differences between the maternal and fetal plasma NPY response to maternal inhalation hypoxia; 2) that NPY may play a role in mediating fetal defense responses to acute hypoxemia; and 3) that fetal exposure to glucocorticoids modifies the fetal plasma NPY response to acute hypoxemia.

Background: The faecal stream plays a significant role in the pathogenesis of Crohn's disease. This retrospective study aimed to assess the effect of faecal diversion on the natural history of refractory Crohn's colitis (RCC) and severe perianal disease (PAD)., Methods: All patients undergoing a defunctioning stoma without resection for RCC or PAD between 1970 and 1997 were studied. Indications for surgery, acute clinical response, subsequent outcome and stoma rates were recorded., Results: Some 73 patients underwent a defunctioning stoma (55 RCC and 18 PAD). Acute remission was achieved in 63 patients (48 RCC, 15 PAD). Twenty-nine patients had subsequent closure of the defunctioning stoma (25 of 48 acute responders with RCC and four of 15 acute responders with PAD). Eleven patients with RCC and two with PAD achieved good long-term function without disease relapse (median follow-up 36 months). Overall 52 patients have undergone proctocolectomy or remain with a defunctioning stoma (37 with RCC and 15 with PAD)., Conclusion: Faecal diversion is associated with acute clinical remission in the majority of patients with RCC and PAD, but sustained benefit occurs less often. For selected patients, diversionary surgery alone offers a realistic alternative to major bowel resection.

Central nervous system glucagon-like peptide-1-(7-36) amide (GLP-1) administration has been reported to acutely reduce food intake in the rat. We here report that repeated intracerebroventricular (i.c.v.) injection of GLP-1 or the GLP-1 receptor antagonist, exendin-(9-39), affects food intake and body weight. Daily i.c.v. injection of 3 nmol GLP-1 to schedule-fed rats for 6 days caused a reduction in food intake and a decrease in body weight of 16 +/- 5 g (P < 0.02 compared with saline-injected controls). Daily i.c.v. administration of 30 nmol exendin-(9-39) to schedule-fed rats for 3 days caused an increase in food intake and increased body weight by 7 +/- 2 g (P < 0.02 compared with saline-injected controls). Twice daily i.c.v. injections of 30 nmol exendin-(9-39) with 2.4 nmol neuropeptide Y to ad libitum-fed rats for 8 days increased food intake and increased body weight by 28 +/- 4 g compared with 14 +/- 3 g in neuropeptide Y-injected controls (P < 0.02). There was no evidence of tachyphylaxis in response to i.c.v. GLP-1 or exendin-(9-39). GLP-1 may thus be involved in the regulation of body weight in the rat.

Agouti-related protein (Agrp) is present in rat and human hypothalamus and is structurally related to agouti protein. Overexpression of either of these proteins results in obesity. However the effect of exogenous Agrp and its in vivo interaction with alpha-melanocyte stimulating hormone (alphaMSH), the likely endogenous melanocortin 3 and 4 receptor (MC3-R and MC4-R) agonist, have not been demonstrated. We report that 1 nmol of Agrp(83-132), a C-terminal fragment of Agrp, when administered intracerebroventricularly (ICV) into rats, increased food intake over a 24-h period (23.0+/-1.4 g saline vs 32.9+/-2.3 g Agrp, p<0.05). The hyperphagia was similar to that seen when 1 nmol of the synthetic MC3-R and MC4-R antagonist SHU9119 was given i.c.v. (19.6+/-1.8 g saline vs 32.5+/-1.7 g SHU9119, p<0.001). Both Agrp(83-132) and SHU9119 blocked the reduction in 1-h food intake of i.c.v. alphaMSH at the beginning of the dark phase. This effect occurred independently of whether the antagonists were administered simultaneously, or nine hours prior, to the alphaMSH. We have also shown Agrp(83-132) is an antagonist at the MC3-R and MC4-R, with similar inhibition of cAMP activation to that previously reported for the full length peptide. In conclusion, Agrp(83-132) administered i.c.v. increases feeding with long lasting effects and is able to inhibit the action of alphaMSH. This interaction may be mediated by the MC3-R and/or MC4-R.

The bioactivity of feverfew (Tanacetum parthenium) leaf extracts has been analysed, by use of a human polymorphonuclear leukocyte (PMNL) bioassay, to assess the relative contributions of solvent extraction and parthenolide content to the biological potency of the extract. Extracts prepared in acetone-ethanol (system 1) contained significantly more parthenolide (mean +/- s.d. 1.3 +/- 0.2% dry leaf weight) than extracts in chloroform-PBS (phosphate-buffered saline; system 2; 0.1 +/- 0.04% dry leaf weight) or PBS alone (system 3; 0.5 +/- 0.1% dry leaf weight). Extract bioactivity, measured as inhibition of phorbol 12-myristate 13-acetate-induced, 5-amino-2,3-dihydro-1,4-phthalazinedione (luminol)-enhanced PMNL, chemiluminescence, followed a similar trend. Extracts inhibited phorbol 12-myristate 13-acetate-induced oxidative burst by amounts which, if solely attributable to parthenolide, indicated parthenolide concentrations for the respective solvent systems of 2.2 +/- 0.6%, 0.2 +/- 0.1% and 0.9 +/- 0.1% dry leaf weight. The mean ratio of parthenolide concentration to the parthenolide equivalent/PMNL-bioactivity value, for acetone-ethanol and PBS extracts were both 1:1.7. Parthenolide, although a key determinant of biological activity for T. parthenium leaf extracts based on the PMNL-bioassay, seems not to be the sole pharmacologically-active constituent. The identical and elevated bioactivity-parthenolide ratios for both organic and aqueons-phase leaf extracts suggest that a proportion of the other bioactive compounds have solubilities similar to that of parthenolide.

There are now six recognized neuropeptide Y (NPY) receptor subtypes (Y1-Y4 and two recently cloned distinct receptors labeled Y5), of which Y1 and one of the Y5's have been suggested could mediate the effect of NPY on feeding. The fragments NPY(2-36) and NPY(3-36), which bind Y1 only poorly, were injected intracerebroventricularly (icv) and found to have similar dose-response relationships to NPY in the stimulation of feeding. However NPY (13-36), which stimulates both Y2 and Y5, caused no increase in food intake, even at high doses. Maximal stimulation with the classical Y1 agonist [Pro34]-NPY produced only 50% of the maximum effect of NPY itself despite fully inhibiting adenylyl cyclase activity in vitro in a Y1 system. The novel fragment [Pro34]-NPY(3-36) is as effective at stimulating food intake as the classical Y1 analogue [Pro34]-NPY but bound to the Y1 receptor with only 1/20th of the affinity of NPY and failed to inhibit adenylyl cyclase through this receptor. [Pro34]-NPY(3-36) is therefore a relatively appetite-selective ligand. Coadministration of high dose NPY(13-36) and [Pro34]NPY did not enhance feeding compared with [Pro34]-NPY alone. In addition, the NPY Y1 receptor antagonist BIBP-3226, which does not bind Y2, Y4, or Y5 receptors, significantly reduced NPY induced feeding. These results indicate that the feeding effect of icv NPY involves a novel receptor and that it is functionally distinct from the recognized receptor subtypes.

This study investigated the relationships between renal allograft interstitial fibrosis, renal function and graft survival. A total of 107 consecutive renal transplant recipients immunosuppressed with cyclosporin were studied. Needle core transplant biopsies were performed before operation and at 1, 6 and 12 months after transplantation. Allograft fibrosis was assessed by histomorphometric analysis of graft interstitial volume fraction. Renal function was measured by isotopic glomerular filtration rate (GFR) measurement at the same time points. Interstitial volume fraction was already high in preperfusion biopsies, significantly increased with time but stabilized at 6 months after transplantation. GFR correlated negatively with interstitial volume fraction at 6 months (P = 0.05). Interstitial volume fraction at 1 month was not a useful predictor of subsequent graft survival but for allografts surviving to 6 months an interstitial volume fraction above 25 per cent predicted significantly poorer survival (P = 0.04). It provides an objective measure of chronic allograft damage and may prove to be a useful surrogate endpoint in the study of therapeutic intervention.