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Notes: Tuberoinfundibular corticotropin-releasing hormone (CRH) neurones are the principal regulators of the hypothalamic-pituitary-adrenal (HPA)-axis. Vasopressin is primarily a neurohypophysial hormone, produced in magnocellular neurones of the hypothalamic paraventricular and supraoptic nuclei, but parvocellular CRH neurones also coexpress vasopressin, which acts as a second ‘releasing factor’ for adrenocorticotropic hormone along with CRH. All stress inputs converge on these hypothalamic neuroendocrine neurones, and the input signals are integrated to determine the output secretion of CRH and vasopressin. Aminergic, cholinergic, GABAergic, glutamatergic and a number of peptidergic inputs have all been implicated in the regulation of CRH/vasopressin neurones. Glucocorticoids inhibit the HPA-axis activity by negative feedback. Interleukin-1 stimulates CRH and vasopressin gene expression, and is implicated in immune-neuroendocrine regulation. cAMP-response element-binding protein phosphorylation may mediate transcriptional activation of both CRH and vasopressin genes, but the roles of AP-1 and other transcription factors remain controversial. Expression profiles of the CRH and vasopressin genes are not uniform after stress exposure, and the vasopressin gene appears to be more sensitive to glucocorticoid suppression.

Notes: Field experiments were conducted to quantify the natural levels of post-dispersal seed predation of arable weed species in spring barley and to identify the main groups of seed predators. Four arable weed species were investigated that were of high biodiversity value, yet of low to moderate competitive ability with the crop. These were Chenopodium album, Sinapis arvensis, Stellaria media and Polygonum aviculare. Exclusion treatments were used to allow selective access to dishes of seeds by different predator groups. Seed predation was highest early in the season, followed by a gradual decline in predation over the summer for all species. All species were taken by invertebrates. The activity of two phytophagous carabid genera showed significant correlations with seed predation levels. However, in general carabid activity was not related to seed predation and this is discussed in terms of the mainly polyphagous nature of many Carabid species that utilized the seed resource early in the season, but then switched to carnivory as prey populations increased. The potential relevance of post-dispersal seed predation to the development of weed management systems that maximize biological control through conservation and optimize herbicide use, is discussed.

Notes: 1. Algal taste and odour is usually associated with open water blooms and eutrophic systems. However, some algal species can produce high biomass under ice-cover, even at low nutrient concentrations, that can impact water quality. This paper describes a winter odour outbreak in oligotrophic Glenmore Reservoir (Calgary, Alberta, Canada), the major algal species, volatile organic compounds (VOCs) and some treatment implications.2. Using sensory, chemical and microscope analyses, we monitored odour, algal biomass and taxa, bacteria and major nutrients. In a preliminary assessment of the effectiveness of standard water treatment with this type of algal biomass and odour, we used bench-scale tests and sampled raw water from the Glenmore treatment plant at successive treatment stages.3. In the winter of 1999–2000 Glenmore ice-cover was delayed, nutrients were characteristically low (TP 〈 ∼5 μg L–1), but organic carbon and bacteria were higher than in previous years.4. During this period there was an increase in algal biomass dominated by the mixotrophic chrysoflagellate Dinobryon divergens. Temporal dynamics of this species were inversely correlated with bacteria, and biomass declined following the establishment of ice-cover, while depth profiles showed the highest abundance at subsurface layers. This suggested that the population outbreak was triggered by high bacteria abundance but depended on a minimum amount of light, consistent with in vitro studies of other mixotrophic chrysophytes.5. Other non-bactiverous taxa were also numerous, notably Asterionella formosa, cryptomonads, dinoflagellates and the synurophyte Synura petersenii.6. Raw water odour was characteristically fishy, mainly caused by the VOCs 2,4,7-decatrienal, 2,4-heptadienal and 2,4-decadienal. Based on algal population and VOC dynamics, these compounds were attributed to Dinobryon. Trace amounts of 2,6-nonadienal (S. petersenii) and 1,3,5 and 1,3,6-octatriene (A. formosa) were also detected. It was concluded that 2,4,7-decatrienal was the major source of the raw water odour.7. Sensory and microscopic analyses of pre- and post-treatment samples in the treatment plant indicated a complete removal of odour, but only a 30–60% removal of algal biomass and evident rupture of residual algal cells. Laboratory experiments showed that using standard treatment, chlorination rapidly oxidized 2,4,7-decatrienal and 2,6-nonadienal but had little effect on 2,4-hepta- and decadienal.

Notes: A 70-year-old Caucasian male developed a left groin tumor with epidermal infiltration of Paget's type. Five months later the ureter was found to be obstructed by a bladder adenocarcinoma cytologically identical to the skin lesion. Both tumors contained carcinoembryonic antibodies, using the immunoperoxidase method. Despite radiation therapy, the patient died a month later. There are no previous reports of association between urinary bladder adenocarcinoma and extramammary Paget's disease of the skin.

Notes: Announces the research done to support the writing of a new text on human resources issues in the international field of tourism and hospitality. Pinpoints the 34 current areas of interest and those identified as of strategic importance for the future.

Notes: The aggressiveness of 20 Northern Ireland single-lesion isolates of Phytophthora infestans was compared following their inoculation onto detached leaflets of three potato cultivars chosen on the basis of their differing levels of race-nonspecific resistance to late blight: Bintje (highly susceptible); Cara (moderately resistant); and Stirling (more resistant). Five isolates from outside Northern Ireland were included for comparative purposes: two from the Republic of Ireland; two from the USA (representing the US-1 and US-8 clonal lineages); and one from Mexico. To control the variation between tests, a balanced incomplete block design was used, as opposed to either a complete block design or the method of inclusion of standard isolates, where such variation would have increased the error. Highly significant variation for disease parameters, including latent period, infection frequency, area under the lesion expansion curve (AULEC) and sporulation capacity, was found between isolates. These differences were much more marked on the cultivars exhibiting higher levels of race-nonspecific resistance. There was a significant interaction between isolate and cultivar for all parameters assessed and, overall, no one isolate was the most aggressive across all three potato cultivars. However, a group comprising seven of the 20 Northern Ireland isolates was consistently found to exhibit the highest levels of aggression towards all three cultivars for each of the disease parameters. These results demonstrate that significant variation for foliar aggressiveness exists within the Northern Ireland population of P. infestans, and indicate the importance of selecting appropriately aggressive isolates for evaluation of host resistance to late blight within breeding programmes.

Notes: The polypeptide hormone gastrin was identified nearly a hundred years ago and its role in the regulation of acid secretion is well established. Gastrin also acts as a growth factor and is trophic for the normal gastric oxyntic mucosa. This growth promoting action has led to the extensive investigation of its role in carcinogenesis, in particular colorectal neoplasia. The relationship between gastrin and colorectal adenocarcinoma has been subject to controversy, however the findings from several recent studies have resulted in a clearer understanding of the mechanism of action of gastrin in this is common cancer.The majority of colorectal cancers produce their own gastrin, which may act in an autocrine manner. The tumour cells also express gastrin/CCKB receptors (and/or a combination of isoforms) which mediate the proliferative action. This locally produced gastrin gives rise to a small increase in systemic gastrin levels. Autocrine gastrin may also have a role in tumour development, as expression occurs early in the adenoma–carcinoma sequence. In addition, several studies using animal models have shown that systemic hypergastrinaemia promotes the proliferation of both normal and neoplastic colonic epithelium. Hyperproliferative colonic epithelium in the presence of hypergastrinaemia has been recorded in humans and a well-designed epidemiological study has demonstrated an increased incidence of colorectal cancer.Gastrin is a potential therapeutic target in the treatment of colorectal cancer and several approaches have been assessed. Receptor antagonists and antisecretory agents have been demonstrated to be ineffectual. Novel methods of inhibition, including the use of anti-gastrin antibodies, are currently being evaluated.