230 research outputs found
Synapsin phosphorylation by SRC tyrosine kinase enhances SRC activity in synaptic vesicles.
Synapsins are synaptic vesicle-associated phosphoproteins implicated in the regulation of neurotransmitter release. Synapsin I is the major binding protein for the SH3 domain of the kinase c-Src in synaptic vesicles. Its binding leads to stimulation of synaptic vesicle-associated c-Src activity. We investigated the mechanism and role of Src activation by synapsins on synaptic vesicles. We found that synapsin is tyrosine phosphorylated by c-Src in vitro and on intact synaptic vesicles independently of its phosphorylation state on serine. Mass spectrometry revealed a single major phosphorylation site at Tyr(301), which is highly conserved in all synapsin isoforms and orthologues. Synapsin tyrosine phosphorylation triggered its binding to the SH2 domains of Src or Fyn. However, synapsin selectively activated and was phosphorylated by Src, consistent with the specific enrichment of c-Src in synaptic vesicles over Fyn or n-Src. The activity of Src on synaptic vesicles was controlled by the amount of vesicle-associated synapsin, which is in turn dependent on synapsin serine phosphorylation. Synaptic vesicles depleted of synapsin in vitro or derived from synapsin null mice exhibited greatly reduced Src activity and tyrosine phosphorylation of other synaptic vesicle proteins. Disruption of the Src-synapsin interaction by internalization of either the Src SH3 or SH2 domains into synaptosomes decreased synapsin tyrosine phosphorylation and concomitantly increased neurotransmitter release in response to Ca(2+)-ionophores. We conclude that synapsin is an endogenous substrate and activator of synaptic vesicle-associated c-Src and that regulation of Src activity on synaptic vesicles participates in the regulation of neurotransmitter release by synapsin
The integration of an augmented reality module within the Way- Cyberparks app. : the case study of Valletta city
Latest improvements on mobile devices capabilities are changing the way people
interact with their surroundings. Nowadays, devices are able to sense the environment and
user’s location, enabling the user to experience improved digital services. This is a key
aspect of public spaces enhancement, which plays a pivotal role for the improvement of
public spaces; a key to make public locations more accessible, interactive and enjoyable.
One of the most powerful technologies enabling this innovative set of services is known
as Augmented Reality (AR). More in depth, AR allows users to visualise in real time virtual
information about the physical objects of the real world, directly on the display of their
own devices. AR provides innovative way-finding widgets and context-awareness services.
Along with the aims of the COST Action Cyberparks, our aim is to improve the App delivered
during the first stages of the project (Way-Cyberparks) with AR functionalities, by developing
a location-based AR module tailored to be integrated within Way-Cyberparks. The AR section
will link virtual geo-tagged annotations as an interface to (geo) spatial and attribute data,
allowing users to quick access digital sensory inputs. The overarching idea is to populate
the App with virtual signage fostering the fruition of public spaces by allowing users to
experience new ways of moving within specific places. Thanks to that, on one hand, the
App works as an interactive path-finder tool, heading visitors towards the most interesting
locations or landmarks within a specific area (Points of Interest or POIs). On the other,
users are enabled to create their own contents and upload them into the network of available
POIs, enabling a true participative community. The city of Valletta has been chosen as first
case study; here the AR module will be tested to identify historical locations and heritage
buildings, acting as contextual objects for the Way- Cyberparks App.Funded by the Horizon 2020 Framework Programme of the European Union.peer-reviewe
In vitro and in vivo efficacy of 6-(7-nitro-2,1,3-benzoxadiazol-4-ylthio)hexanol (NBDHEX) on human melanoma
6-(7-Nitro-2,1,3-benzoxadiazol-4-ylthio)hexanol (NBDHEX) is a powerful inhibitor of the glutathione transferase P1-1 (GSTP1-1) and causes the disruption of the complex between GSTP1-1 and c-Jun N-terminal Kinase (JNK). This induces JNK activation and apoptosis in tumour cells. in the present work we assess the in vitro and in vivo effectiveness of NBDHEX on two human melanoma cell lines, Me501 and A375. NBDHEX shows IC50 values in the low micromolar range (IC50 of 1.2 +/- 0.1 mu M and 2.0 +/- 0.2 mu M for Me501 and A375, respectively) and is over 100 times more cytotoxic to these cell lines than temozolomide. Apoptosis is observed in Me501 cells within 3 h of the addition of NBDHEX, while in A375 cells the apoptotic event is rather late, and is preceded by a G2/M phase arrest. In both melanoma cell lines, INK activity is required for the ability of NBDHEX to trigger apoptosis, confirming that the JNK pathway is an important therapeutic target for this tumour. NBDHEX is also both effective and well tolerated in in vivo tumour models. A tumour inhibition of 70% is observed in vivo against Me501 human melanoma and a similar result is obtained on A375 model, with 63% of turnout inhibition. These findings indicate that the activation of the JNK pathway, through a selective GSTP1-1 targeting, could prove to be a promising new strategy for treating melanoma, which responds poorly to conventional therapies. (C) 2009 Elsevier Ltd. All rights reserved
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Land Governance and Inclusive business in Agriculture: Advancing the Debate
This paper reviews the state of the global debate on the idea of inclusive agricultural investments by assessing, and makes an original contribution by interrogating the core features of inclusive business relations in Agriculture.
Based on an assessment of areas of agreement in what ‘inclusiveness’ in agribusiness means to different business, civil society and development agency stakeholders is considered to mean, drawn from the policy literature in a series of interviews, five “pillars” of inclusive agribusiness are identified: effective arrangements for farmer representation, fair value chain relations, respect for land rights and agreement on tenure relations, employment creation and respect for labour rights, and contributions to food security. A literature review of crop and market characteristics identified four key variables that influence business configurations in different sectors (crop characteristics, scope for mechanisation, capital investment requirements, and market destinations and conditions) to develop a simple typology of value chain types: perishables linked to distant markets; labour intensive, hard-to-mechanise crops with high perishability and bulk; and labour intensive crops with high perishability and bulk that can be fully mechanised. Each of these value chain types was then examined in relation to the five dimensions of inclusiveness through literature based case studies of specific commodity sectors and geographies, respectively: high value horticulture in East Africa and the Andes; oil palm in Southeast Asia and Colombia, and sugarcane in eastern and southern Africa.
Significantly, the analysis finds that without an understanding of how crop and value chain characteristics and market trends shape opportunities and constraints in specific geographies and commodity sectors it is difficult to advance inclusiveness in agribusiness or develop effective public policy. Inclusiveness is found not to be inherent in specific types of business models, such as large plantations, outgrower schemes or contract farming, but rather a matter of degree, dependent on context, the crops and commodities n question and the outcomes for different social groups. These outcomes are affected by trade-offs amongst the different pillars of inclusiveness and how they are managed. Large plantations may create employment but also pose risks to local community land rights and food security. Labour intensive crops that are hard to mechanise encourage firms to engage smallholder suppliers, but the quality and terms of engagement are highly variable. Drives to increase efficiency can undermine inclusiveness and market restructuring have raised the bar for smallholder participation. Where small farmers have secure control over land resources companies have greater incentives to work with them, and as control over land has a bearing on all five dimensions of inclusiveness, land governance is a key area for attention in promoting greater social and economic inclusion in agriculture.
The paper offers an original and rigorous approach to understanding inclusiveness in agribusiness by focussing on the processes and terms through which small scale farming communities are incorporated and the distributive outcomes of specific productive arrangements in different value chains. It has been welcomed within development agencies and the investment community as providing a fresh analytical perspective and a framework for advancing social and economic inclusion in agribusiness investment in practice
Quantitative Microbial Risk Assessment as support for bathing waters profiling
Profiling bathing waters supported by Quantitative Microbial Risk Assessment (QMRA) is key to the WHO's recommendations for the 2020/2021 revision of the European Bathing Water Directive. We developed an areaspecific QMRA model on four pathogens, using fecal indicator concentrations (E. coil, enterococci) for calculating pathogen loads. The predominance of illness was found to be attributable to Human Adenovirus, followed by Salmonella, Vibrio, and Norovirus. Overall, the cumulative illness risk showed a median of around 1 case/10000 exposures. The risk estimates were strongly influenced by the indicators that were used, suggesting the need for a more detailed investigation of the different sources of fecal contamination. Area-specific threshold values for fecal indicators were estimated on a risk-basis by modelling the cumulative risk against E. coll. and enterococci concentrations. To improve bathing waters assessment, we suggest considering source apportionment locally estimating of pathogen/indicator ratios, and calculating site-specific indicators thresholds based on risk assessment
Environmental conditions, air pollutants, and airway cells in runners: a longitudinal field study
Cysteinyl Leukotriene-1 Receptor Activation in a Human Bronchial Epithelial Cell Line Leads to Signal Transducer and Activator of Transcription 1-Mediated Eosinophil Adhesion
Environmental conditions, air pollutants, and airway cells in runners: A longitudinal field study
Substrate distortion and the catalytic reaction mechanism of 5-carboxyvanillate decarboxylase
5-Carboxyvanillate decarboxylase (LigW) catalyzes the conversion of 5-carboxyvanillate to vanillate in the biochemical pathway for the degradation of lignin. This enzyme was shown to require Mn2+ for catalytic activity and the kinetic constants for the decarboxylation of 5-carboxyvanillate by the enzymes from Sphingomonas paucimobilis SYK-6 (kcat = 2.2 s–1 and kcat/Km = 4.0 × 104 M–1 s–1) and Novosphingobium aromaticivorans (kcat = 27 s–1 and kcat/Km = 1.1 × 105 M–1 s–1) were determined. The three-dimensional structures of both enzymes were determined in the presence and absence of ligands bound in the active site. The structure of LigW from N. aromaticivorans, bound with the substrate analogue, 5-nitrovanillate (Kd = 5.0 nM), was determined to a resolution of 1.07 Å. The structure of this complex shows a remarkable enzyme-induced distortion of the nitro-substituent out of the plane of the phenyl ring by approximately 23°. A chemical reaction mechanism for the decarboxylation of 5-carboxyvanillate by LigW was proposed on the basis of the high resolution X-ray structures determined in the presence ligands bound in the active site, mutation of active site residues, and the magnitude of the product isotope effect determined in a mixture of H2O and D2O. In the proposed reaction mechanism the enzyme facilitates the transfer of a proton to C5 of the substrate prior to the decarboxylation step
Payers' views of the changes arising through the possible adoption of adaptive pathways
Payers are a major stakeholder in any considerations and initiatives concerning adaptive licensing of new medicinal products, also referred to as Medicines Adaptive Pathways to patients (MAPPs). Firstly, the scope and necessity of MAPPs need further scrutiny, especially with regard to the definition of unmet need. Conditional approval pathways already exist for new medicines for seriously debilitating or life-threatening diseases and only a limited number of new medicines are innovative. Secondly, MAPPs will result in new medicines on the market with limited evidence about their effectiveness and safety. Additional data are to be collected after approval. Consequently, adaptive pathways may increase the risk of exposing patients to ineffective or unsafe medicines. We have already seen medicines approved conventionally that subsequently proved ineffective or unsafe amongst a wider, more co-morbid population as well as medicines that could have been considered for approval under MAPPs but subsequently proved ineffective or unsafe in Phase III trials and were never licensed. Thirdly, MAPPs also put high demands on payers. Routine collection of patient level data is difficult with high transaction costs. It is not clear who will fund these. Other challenges for payers include shifts in the risk governance framework, implications for evaluation and HTA, increased complexity of setting prices, difficulty with ensuring equity in the allocation of resources, definition of responsibility and liability and implementation of stratified use. Exit strategies also need to be agreed in advance, including price reductions, rebates, or reimbursement withdrawals when price premiums are not justified. These issues and concerns will be discussed in detail including potential ways forward
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