745 research outputs found

    Digestive Proteolytic Activity in the Sunn Pest, Eurygaster integriceps

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    The Sunn pest, Eurygaster integriceps Puton (Heteroptera: Scutelleridae), is one of the most important pests of wheat and causes considerable damage to this valuable crop annually. Digestive proteinase activity of adult insects was investigated using general and specific substrates and inhibitors. Proteolytic activity was low when the common conventional substrates, azoalbumin, azocasein and hemoglobin were used to assay salivary glands and midguts. Using the fluorescent casein substrate (BODIPY FL casein), total proteolytic activity was measured at different pH. Maximum proteolytic activity was detected at pH 7 (100%) and 8(65%) which suggested the presence of serine proteinases in the salivary glands. There was no detectable proteolytic activity in midgut extracts. The inhibitors; PMSF (inhibitor of serine proteinases) and TPCK (a specific chymotrypsin inhibitor) showed greater than 50% inhibitory effect on total proteolytic activity, however, TLCK (specific trypsin inhibitor) and E-64(specific cysteine proteinase inhibitor) did not inhibit total proteolytic activity. Using fluorescent specific substrates for serine and cysteine proteinases (Z-Arg-AMC, Z-Arg-Arg-AMC, Z-Arg-Phe-AMC and Suc-Ala-Ala-Pro-Phe-AMZ) revealed the presence of tryptic and chymotryptic activity in the salivary gland extract. Zymogram analysis under non-reducing SDS-PAGE conditions and using the substrate APNE showed at least 8 tryptic and chymotryptic activity bands in salivary gland extracts. A single high molecular weight band with tryptic activity (165 kDa) was detected using the substrate BApNA in a zymogram analysis uisng native-PAGE. Kinetic studies showed a km value of 0.6 mM for this enzyme against the substrate BApNA .The inhibitor TLCK decreased activity of the trypsin-like enzyme up to 73% and almost completely eliminated the only band related to this proteinase in the zymogram. Soybean Kunitz type trypsin inhibitor showed no effect on proteolytic activity of the trypsin-like serine proteinase. In general, the results revealed the presence of chymotrypsin- and trypsin-like serine proteinases in the salivary gland of E. integriceps, and it seems that the major total proteolytic activity is due to chymotrypsin proteinases

    Game Theoretical Interactions of Moving Agents

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    Game theory has been one of the most successful quantitative concepts to describe social interactions, their strategical aspects, and outcomes. Among the payoff matrix quantifying the result of a social interaction, the interaction conditions have been varied, such as the number of repeated interactions, the number of interaction partners, the possibility to punish defective behavior etc. While an extension to spatial interactions has been considered early on such as in the "game of life", recent studies have focussed on effects of the structure of social interaction networks. However, the possibility of individuals to move and, thereby, evade areas with a high level of defection, and to seek areas with a high level of cooperation, has not been fully explored so far. This contribution presents a model combining game theoretical interactions with success-driven motion in space, and studies the consequences that this may have for the degree of cooperation and the spatio-temporal dynamics in the population. It is demonstrated that the combination of game theoretical interactions with motion gives rise to many self-organized behavioral patterns on an aggregate level, which can explain a variety of empirically observed social behaviors

    Retrospective harm benefit analysis of pre-clinical animal research for six treatment interventions

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    The harm benefit analysis (HBA) is the cornerstone of animal research regulation and is considered to be a key ethical safeguard for animals. The HBA involves weighing the anticipated benefits of animal research against its predicted harms to animals but there are doubts about how objective and accountable this process is.i. To explore the harms to animals involved in pre-clinical animal studies and to assess these against the benefits for humans accruing from these studies; ii. To test the feasibility of conducting this type of retrospective HBA.Data on harms were systematically extracted from a sample of pre-clinical animal studies whose clinical relevance had already been investigated by comparing systematic reviews of the animal studies with systematic reviews of human studies for the same interventions (antifibrinolytics for haemorrhage, bisphosphonates for osteoporosis, corticosteroids for brain injury, Tirilazad for stroke, antenatal corticosteroids for neonatal respiratory distress and thrombolytics for stroke). Clinical relevance was also explored in terms of current clinical practice. Harms were categorised for severity using an expert panel. The quality of the research and its impact were considered. Bateson's Cube was used to conduct the HBA.The most common assessment of animal harms by the expert panel was 'severe'. Reported use of analgesia was rare and some animals (including most neonates) endured significant procedures with no, or only light, anaesthesia reported. Some animals suffered iatrogenic harms. Many were kept alive for long periods post-experimentally but only 1% of studies reported post-operative care. A third of studies reported that some animals died prior to endpoints. All the studies were of poor quality. Having weighed the actual harms to animals against the actual clinical benefits accruing from these studies, and taking into account the quality of the research and its impact, less than 7% of the studies were permissible according to Bateson's Cube: only the moderate bisphosphonate studies appeared to minimise harms to animals whilst being associated with benefit for humans.This is the first time the accountability of the HBA has been systematically explored across a range of pre-clinical animal studies. The regulatory systems in place when these studies were conducted failed to safeguard animals from severe suffering or to ensure that only beneficial, scientifically rigorous research was conducted. Our findings indicate a pressing need to: i. review regulations, particularly those that permit animals to suffer severe harms; ii. reform the processes of prospectively assessing pre-clinical animal studies to make them fit for purpose; and iii. systematically evaluate the benefits of pre-clinical animal research to permit a more realistic assessment of its likely future benefits

    GMOs: Non-Health Issues

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    The controversy over genetically modified [GM] organisms is often framed in terms of possible hazards for human health. Articles in a previous volume of this *Encyclopedia* give a general overview of GM crops [@Mulvaney2014] and specifically examine human health [@Nordgard2014] and labeling [@Bruton2014] issues surrounding GM organisms. This article explores several other aspects of the controversy: environmental concerns, political and legal disputes, and the aim of "feeding the world" and promoting food security. Rather than discussing abstract, hypothetical GM organisms, this article explores the consequences of the GM organisms that have actually been deployed in the particular contexts that they have been deployed, on the belief that there is little point in discussing GM organisms in an idealized or context-independent way

    Neuroscience, Ethics, and National Security: The State of the Art

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    Military involvement and research in neuroscience generates unique ethical, legal, and social issues that require careful elucidation and consideration in order to align the potentially conflicting needs of national defense, public interest, and scientific progress

    The Eastern Origins of the Rise of the West and the “Return” of Asia

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    With the current interest in China (and India) proliferating within the Western Academy, this article claims that what we are witnessing today is not the rise but the “return” of China (and India). Many academics assume that the West has been the dominant civilization in the world economy in the last 500 years and that the current “rise” of China threatens to knock the West off its perch. However, this article provides an alternative take to this cherished axiom of Eurocentric world history by inverting the standard belief that the West pioneered modernity and then expanded outwards to remake the world. Thus, I argue not only that globalization preceded the rise of the West but that it was Eastern-led on the one hand and that it enabled the Western breakthrough into modernity on the other. This, in turn, rests on my claim that Chinese development stems back not to 1978 but to 960 ce as the Sung Dynasty emerged and subsequently undertook a quasi-industrial miracle. Moreover, between 1450/1492 and ca. 1830 China lay at the centre of the nascent global economy, fanning the integration process alongside other key non-Western regions such as India and West Asia/North Africa. And, while the West was the dominant player after ca. 1830 down to the turn of the third millennium, nevertheless, what we witness today is the return of China to the centre of the global economy whence it came

    Divergent mind-sets, convergent policies: Policing models against organized crime in Italy and in England within international frameworks

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    The fight against organized crime is a very fertile ground for policymaking at various levels. On one side, because of the perceived transnationality of the phenomenon, national states are inclined to develop harmonized responses within the European or international law frameworks. On the other side, national conceptualizations and manifestations of organized crime often make these harmonizations quite challenging. This paper shares the findings of a socio-legal investigation carried out in England and in Italy through interviews and document analysis, comparing the two national models against organized crime. The paper presents these two models ? the Italian Structure Model and the English Activity Model, which are very different in many ways ? in order to identify divergences and convergences of policies and practices. This comparative exercise not only improves our understanding of national approaches, beyond cultural, linguistic and legal boundaries, but also improves the dialogue towards concerted efforts at the international level. Nevertheless, the globalization of criminal markets and the internationalization of policies have influenced perceptions of organized crime and related policing tactics at national levels too. This paper will briefly look at international perspectives to assess to what extent divergent and convergent areas between the two models are also areas of interest and focus at the international level, in order to conclude with an enhanced understanding of both models before drawing conclusions

    Weekends-off efavirenz-based antiretroviral therapy in HIV-infected children, adolescents and young adults (BREATHER): Extended follow-up results of a randomised, open-label, non-inferiority trial

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    BACKGROUND: Weekends off antiretroviral therapy (ART) may help engage HIV-1-infected young people facing lifelong treatment. BREATHER showed short cycle therapy (SCT; 5 days on, 2 days off ART) was non-inferior to continuous therapy (CT) over 48 weeks. Planned follow-up was extended to 144 weeks, maintaining original randomisation. METHODS: BREATHER was an open-label, non-inferiority trial. Participants aged 8-24yrs with virological suppression on efavirenz-based first-line ART were randomised 1:1, stratified by age and African/non-African sites, to remain on CT or change to SCT. The Kaplan-Meier method was used to estimate the proportion of participants with viral rebound (confirmed VL≥50 copies/mL) under intent-to-treat at 48 weeks (primary outcome), and in extended follow-up at 96, 144, and 192 weeks. SCT participants returned to CT following viral rebound, 3 VL blips or discontinuation of efavirenz. FINDINGS: Of 199 participants (99 SCT, 100 CT), 97 per arm consented to extended follow-up. Median follow-up was 185.3 weeks (IQR 160.9-216.1). 69 (70%) SCT participants remained on SCT at last follow-up. 105 (53%) were male, baseline median age 14 years (IQR 12-18), median CD4 count 735 cells/μL (IQR 576-968). 16 SCT and 16 CT participants had confirmed VL≥50 copies/mL by the end of extended follow-up (HR 1.00, 95% CI 0.50-2.00). Estimated difference in percentage with viral rebound (SCT minus CT) by week 144 was 1.9% (90% CI -6.6-10.4; p = 0.72) and was similar in a per-protocol analysis. There were no significant differences between arms in proportions of participants with grade 3/4 adverse events (18 SCT vs 16 CT participants; p = 0.71) or ART-related adverse events (10 vs 12; p = 0.82). 20 versus 8 serious adverse events (SAEs) were reported in 16 SCT versus 4 CT participants, respectively (p = 0.005 comparing proportions between groups; incidence rate ratio 2.49, 95%CI 0.71-8.66, p = 0.15). 75% of SAEs (15 SCT, 6 CT) were hospitalisations for a wide range of conditions. 3 SCT and 6 CT participants switched to second-line ART following viral failure (p = 0.50). CONCLUSIONS: Sustainable non-inferiority of virological suppression in young people was shown for SCT versus CT over median 3.6 years. Standard-dose efavirenz-based SCT is a viable option for virologically suppressed HIV-1 infected young people on first-line ART with 3-monthly VL monitoring. TRIAL REGISTRATION: EudraCT 2009-012947-40 ISRCTN 97755073 ClinicalTrials.gov NCT01641016
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