38 resultados para Aggressive

em CentAUR: Central Archive University of Reading - UK


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For the tracking of extrema associated with weather systems to be applied to a broad range of fields it is necessary to remove a background field that represents the slowly varying, large spatial scales. The sensitivity of the tracking analysis to the form of background field removed is explored for the Northern Hemisphere winter storm tracks for three contrasting fields from an integration of the U. K. Met Office's (UKMO) Hadley Centre Climate Model (HadAM3). Several methods are explored for the removal of a background field from the simple subtraction of the climatology, to the more sophisticated removal of the planetary scales. Two temporal filters are also considered in the form of a 2-6-day Lanczos filter and a 20-day high-pass Fourier filter. The analysis indicates that the simple subtraction of the climatology tends to change the nature of the systems to the extent that there is a redistribution of the systems relative to the climatological background resulting in very similar statistical distributions for both positive and negative anomalies. The optimal planetary wave filter removes total wavenumbers less than or equal to a number in the range 5-7, resulting in distributions more easily related to particular types of weather system. For the temporal filters the 2-6-day bandpass filter is found to have a detrimental impact on the individual weather systems, resulting in the storm tracks having a weak waveguide type of behavior. The 20-day high-pass temporal filter is less aggressive than the 2-6-day filter and produces results falling between those of the climatological and 2-6-day filters.

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Metastatic malignant melanoma remains a highly aggressive form of skin cancer for which no reliable methods for treatment exist. Given the increasing incidence of this cancer, considerable attention has focused on the development of new and improved methods for tackling this disease. Within this article, methods for treating melanoma are reviewed and discussed with particular attention focusing on prodrugs that are activated by the tyrosinase enzyme. This enzyme is up-regulated and is of elevated activity within malignant melanomas compared with healthy melanocytes, providing an ideal in-situ tool for the activation of melanoma prodrugs. By way of background to the prodrug strategies discussed within this review, the causes of melanoma, the enzymology of tyrosinase, and the chemistry of the biosynthetic pathways associated with melanogenesis are presented. Aspects of the design, mode of action, and biological profiles of key prodrugs that are activated by tyrosinase, and that show potential for the treatment of melanoma, are then presented and compared.

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The overall immunopathogenesis relevant to a large series of disorders caused by a drug or its associated hyperimmune condition is discussed based upon the examination of the genetics of severe drug-induced bullous skin problems (sporadic idiosyncratic adverse events, including Stevens-Johnson syndrome and toxic epidermal necrolysis). An overarching pharmacogenetic schema is proposed. Immune cognition and early-effector processes are focused upon and a challenging synthesis around systems evolution is explained by a variety of projective analogies. Etiology, human leukocyte antigen-B, immune stability, clysiregulation, pharmacomimicry, viruses and an aggressive ethnically differentiated 'karmic' response are discussed.

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Despite theoretical predictions, dishonest signalling has rarely been observed in aggressive interactions. We present evidence of such signalling in the nonpollinating. g wasp Philotrypesis sp. A ex Ficus rubiginosa. First, morphometric data indicated that an alternative 'atypical' male morph (17.8% of individuals) exists that tends to be larger in body size and has longer mandibles for a given body size than other 'typical' males. Second, behavioural observations suggested that males use mandible gape width (which depends on mandible length) as a cue to assess opponents before fights and retreat without escalating if they are unlikely to win, and, probably because their greater mandible gape width causes more opponents to retreat without escalating, that atypical males engaged in fewer fights than typical males for a given body size but had higher mating success. Third, atypical males were less likely to win fights than typical males of similar mandible length relative to opponents. In addition, we found that atypical males incur more injuries (greater receiver-dependent signal costs) than typical males of similar body size relative to rivals. We discuss the implications of our findings for future work on dishonest signalling. (C) 2009 The Association for the Study of Animal Behaviour. Published by Elsevier Ltd. All rights reserved.

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Artificial pod inoculation was used to compare the relative aggressiveness of seven Colombian isolates of Moniliophthora roreri (the causal agent of moniliasis or frosty pod disease), representing four major genetic groupings of the pathogen in cacao (cocoa), when applied to five diverse cacao genotypes (ICS-1, ICS-95, TSH-565, SCC-61 and CAP-34) at La Suiza Experimental Farm, Santander Department, Colombia. The following variables were evaluated 9 weeks after inoculation of 2- to 3-month-old pods with spore suspensions (1.2 x 10(5) spores mL(-1)): (i) disease incidence (DI); (ii) external severity (ES); and (iii) internal severity (IS). IS was found to be of greatest value in classifying the reaction of the host genotype against M. roreri. Genetic variation reported between isolates and cacao genotypes was not matched by similar diversity in their aggressiveness. All isolates were generally highly aggressive against most cacao genotypes, with only two isolates showing reduced IS and ES reactions. There was considerable variation between clones in the IS and ES scores, but one cultivated clone (ICS-95) displayed a significant level of resistance against all seven isolates. This clone may be useful in cacao breeding initiatives for resistance to moniliasis of cacao.

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The development of normal and abnormal glandular structures in the prostate is controlled at the endocrine and paracrine levels by reciprocal interactions between epithelium and stroma. To study these processes it is useful to have an efficient method of tissue acquisition for reproducible isolation of cells from defined histologies. Here we assessed the utility of a standardized system for acquisition and growth of prostatic cells from different regions of the prostate with different pathologies, and we compared the abilities of stromal cells from normal peripheral zone (PZ-S), benign prostatic hyperplasia (BPH-S), and cancer (CA-S) to induce the growth of a human prostatic epithelial cell line (BPH-1) in vivo. Using the tissue recombination method, we showed that grafting stromal cells (from any histology) alone, or BPH-1 epithelial cells alone produced no visible grafts. Recombining PZ-S with BPH-1 cells also produced no visible grafts (n = 15). Recombining BPH-S with BPH-1 cells generated small, well-organized and sharply demarcated grafts approximately 3-4 mm in diameter (n = 9), demonstrating a moderate inductive ability of BPH-S. Recombining CA-S with BPH-1 cells generated highly disorganized grafts that completely surrounded the host kidney and invaded into adjacent renal tissue, demonstrating induction of an aggressive phenotype. We conclude that acquisition of tissue from toluidine blue dye stained specimens is an efficient method to generate high quality epithelial and/or stromal cultures. Stromal cells derived by this method from areas of BPH and cancer induce epithelial cell growth in vivo which mimics the natural history of these diseases.

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Objectives: To determine the incidence and clinical relevance of newly diagnosed cases of prostate cancer in a group of men who had an elevated PSA and benign prostate biopsy 7 years previously. Patients and Method: Patients under the age of 80 years with an elevated PSA who had had a benign prostate biopsy in the 12 months between March 1, 1994 and February 28, 1995 were studied. One hundred and sixty four patients with a mean age of 66.8 years (range 47-79 years) were identified. The mean PSA for this group was 10.3 ng/ml (range 4.1-81 ng/ml). One hundred and fifty nine of the 164 (97%) hospital records were available for review and all but 21 (12.8%) of the General Practitioners were contacted. Results: Eighteen (11%) of the original 164 patients were subsequently diagnosed with prostate cancer, 2 died from their disease. Conclusions: In a population where the follow-up of patients with a benign biopsy was arranged on clinical grounds alone, 11% of the study group were diagnosed with prostate cancer during a seven-year follow-up. Although some of these cancers appear to be slow growing, most of those diagnosed in the initial follow-up period were deemed to be clinically significant and a small proportion progressed rapidly to metastases. All patients who have an elevated PSA, but benign biopsy, should undergo a period of PSA monitoring until it is clear that their PSA is not rising. We propose an initial intensive monitoring period to avoid missing those with clinically aggressive disease. (C) 2003 Elsevier Science B.V. All rights reserved.

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Background Little is known about the relative effects of exposure to postnatal depression and parental conflict on the social functioning of school-aged children. This is, in part, because of a lack of specificity in the measurement of child and parental behaviour and a reliance on children's reports of their hypothetical responses to conflict in play. Methods In the course of a prospective longitudinal study of children of postnatally depressed and well women, 5-year-old children were videotaped at home with a friend in a naturalistic dressing-up play setting. As well as examining possible associations between the occurrence of postnatal depression and the quality of the children's interactions, we investigated the influence of parental conflict and co-operation, and the continuity of maternal depression. The quality of the current mother-child relationship was considered as a possible mediating factor. Results Exposure to postnatal depression was associated with increased likelihood, among boys, of displaying physical aggression in play with their friend. However, parental conflict mediated the effects of postnatal depression on active aggression during play, and was also associated with displays of autonomy and intense conflict. While there were no gender effects in terms of the degree or intensity of aggressive behaviours, girls were more likely to express aggression verbally using denigration and gloating whereas boys were more likely to display physical aggression via interpersonal and object struggles. Conclusions The study provided evidence for the specificity of effects, with strong links between parental and child peer conflict. These effects appear to arise from direct exposure to parental conflict, rather than indirectly, through mother-child interactions.

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Experiments are presented which show that Botrytis cinerea, the cause of gray mould disease, is often present in symptomless lettuce plants as a systemic, endophytic, infection which may arise from seed. The fungus was isolated on selective media from surface sterilized sections of roots, stem pieces and leaf discs from symptomless plants grown in a conventional glasshouse and in a spore-free air-flow provided by an isolation propagator. The presence of B. cinerea was confirmed by immuno-labelling the tissues with the Botrytis-specific monoclonal antibody BC-12.CA4. As plants grew, infection spread from the roots to stems and leaves. Surface sterilization of seeds reduced the number of infected symptomless plants. Artificial infection of seedlings with dry conidia increased the rate of infection in some experiments. Selected isolates were genetically finger-printed using microsatellite loci. This confirmed systemic spread of the inoculating isolates but showed that other isolates were also present and that single plants hosted multiple isolates. This shows that B. cinerea commonly grows in lettuce plants as an endophyte, as has already been shown for Primula. If true for other hosts, the endophytic phase may be as important a component of the species population as the aggressive necrotrophic phase.

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This study tested the hypothesis that aggressive, localized infections and asymptomatic systemic infections were caused by distinct specialized groups of Botrytis cinerea, using microsatellite genotypes at nine loci of 243 isolates of B. cinerea obtained from four hosts (strawberry (Fragaria ´ananassa), blackberry (Rubus fruticosus agg.), dandelion, (Taraxacum of®- cinale agg.) and primrose (Primula vulgaris)) in three regions in southern England (in the vicinities of Brighton, Reading and Bath). The populations were extremely variable, with up to 20 alleles per locus and high genic diversity. Each host in each region had a population of B. cinerea with distinctive genetic features, and there were also consistent host and regional distinctions. The B. cinerea population from strawberry was distinguished from that on other hosts, including blackberry, most notably by a common 154-bp amplicon at locus 5 (present in 35 of 77 samples) that was rare in isolates from other hosts (9¤166), and by the rarity (3¤77) of a 112-bp allele at locus 7 that was common (58¤166) in isolates from other hosts. There was signi®cant linkage disequilibrium overall within the B. cinerea populations on blackberry and strawberry, but with quite different patterns of association among isolates from the two hosts. No evidence was found for differentiation between populations of B. cinerea from systemically infected hosts and those from locally infected fruits.

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A bias towards attributing hostile intent to others has been linked to aggression. In an adolescent sample, we investigated whether peer group homophily exists in the tendency towards attributing hostile intent. We assessed hostile attribution tendencies and self-reported aggressive behaviours in a normative sample of 910 adolescents, and computed average peer group scores based on nominated friend scores. Results indicated that adolescents showed significant correlations between their own level of hostile attributions and that of their peer group. Further analyses indicated that this effect occurred specifically in reciprocal friendships, and was retained even once own and peer group level of aggression were controlled.

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BACKGROUND: Due to the heterogeneity in the biological behavior of prostate cancer, biomarkers that can reliably distinguish indolent from aggressive disease are urgently needed to inform treatment choices. METHODS: We employed 8-plex isobaric Tags for Relative and Absolute Quantitation (iTRAQ), to profile the proteomes of two distinct panels of isogenic prostate cancer cells with varying growth and metastatic potentials, in order to identify novel biomarkers associated with progression. The LNCaP, LNCaP-Pro5, and LNCaP-LN3 panel of cells represent a model of androgen-responsive prostate cancer, while the PC-3, PC-3M, and PC-3M-LN4 panel represent a model of androgen-insensitive disease. RESULTS: Of the 245 unique proteins identified and quantified (>or=95% confidence; >or=2 peptides/protein), 17 showed significant differential expression (>or=+/-1.5), in at least one of the variant LNCaP cells relative to parental cells. Similarly, comparisons within the PC-3 panel identified 45 proteins to show significant differential expression in at least one of the variant PC-3 cells compared with parental cells. Differential expression of selected candidates was verified by Western blotting or immunocytochemistry, and corresponding mRNA expression was determined by quantitative real-time PCR (qRT-PCR). Immunostaining of prostate tissue microarrays for ERp5, one of the candidates identified, showed a significant higher immunoexpression in pre-malignant lesions compared with non-malignant epithelium (P < 0.0001, Mann-Whitney U-test), and in high Gleason grade (4-5) versus low grade (2-3) cancers (P < 0.05). CONCLUSIONS: Our study provides proof of principle for the application of an 8-plex iTRAQ approach to uncover clinically relevant candidate biomarkers for prostate cancer progression.

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Aggression in young people has been associated with a bias towards attributing hostile intent to others; however, little is known about the origin of biased social information processing. The current study explored the potential role of peer contagion in the emergence of hostile attribution in adolescents. 134 adolescents were assigned to one of two manipulated ‘chat-room’ conditions, where they believed they were communicating with online peers (e-confederates) who endorsed either hostile or benign intent attributions. Adolescents showed increased hostile attributions following exposure to hostile e-confederates and reduced hostility in the benign condition. Further analyses demonstrated that social anxiety was associated with a reduced tendency to take on hostile peer attitudes. Neither gender nor levels of aggression influenced individual susceptibility to peer influence, but aggressive adolescents reported greater affinity with hostile e-confederates.

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This paper proposes hybrid capital securities as a significant part of senior bank executive incentive compensation in light of Basel III, a new global regulatory standard on bank capital adequacy and liquidity agreed by the members of the Basel Committee on Banking Supervision. The committee developed Basel III in a response to the deficiencies in financial regulation brought about by the global financial crisis. Basel III strengthens bank capital requirements and introduces new regulatory requirements on bank liquidity and bank leverage. The hybrid bank capital securities we propose for bank executives’ compensation are preferred shares and subordinated debt that the June 2004 Basel II regulatory framework recognised as other admissible forms of capital. The past two decades have witnessed dramatic increase in performance-related pay in the banking industry. Stakeholders such as shareholders, debtholders and regulators criticise traditional cash and equity-based compensation for encouraging bank executives’ excessive risk taking and short-termism, which has resulted in the failure of risk management in high profile banks during the global financial crisis. Paying compensation in the form of hybrid bank capital securities may align the interests of executives with those of stakeholders and help banks regain their reputation for prudence after years of aggressive risk-taking. Additionally, banks are desperately seeking to raise capital in order to bolster balance sheets damaged by the ongoing credit crisis. Tapping their own senior employees with large incentive compensation packages may be a viable additional source of capital that is politically acceptable in times of large-scale bailouts of the financial sector and economically wise as it aligns the interests of the executives with the need for a stable financial system.

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The Maitreyi (Friendship) Express, the rail service between India and Bangladesh that was restarted recently evoked nostalgia and hopes for stronger ties between the two nations. However, it will take more than a rail link to deal with fears of infiltration by Bangladeshi Muslims that is being used in aggressive political rhetoric.