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1.
Biochem J ; 472(2): 169-81, 2015 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-26385991

RESUMEN

High temperature requirement A1 (HtrA1) is a trypsin-fold serine protease implicated in the progression of age-related macular degeneration (AMD). Our interest in an antibody therapy to neutralize HtrA1 faces the complication that the target adopts a trimeric arrangement, with three active sites in close proximity. In the present study, we describe antibody 94, obtained from a human antibody phage display library, which forms a distinct macromolecular complex with HtrA1 and inhibits the enzymatic activity of recombinant and native HtrA1 forms. Using biochemical methods and negative-staining EM we were able to elucidate the molecular composition of the IgG94 and Fab94 complexes and the associated inhibition mechanism. The 246-kDa complex between the HtrA1 catalytic domain trimer (HtrA1_Cat) and Fab94 had a propeller-like organization with one Fab bound peripherally to each protomer. Low-resolution EM structures and epitope mapping indicated that the antibody binds to the surface-exposed loops B and C of the catalytic domain, suggesting an allosteric inhibition mechanism. The HtrA1_Cat-IgG94 complex (636 kDa) is a cage-like structure with three centrally located IgG94 molecules co-ordinating two HtrA1_Cat trimers and the six active sites pointing into the cavity of the cage. In both complexes, all antigen-recognition regions (paratopes) are found to bind one HtrA1 protomer and all protomers are bound by a paratope, consistent with the complete inhibition of enzyme activity. Therefore, in addition to its potential therapeutic usefulness, antibody 94 establishes a new paradigm of multimeric serine protease inhibition.


Asunto(s)
Anticuerpos Neutralizantes/farmacología , Complejo Antígeno-Anticuerpo/química , Antineoplásicos/farmacología , Melanoma/tratamiento farmacológico , Proteínas de Neoplasias/antagonistas & inhibidores , Inhibidores de Proteasas/farmacología , Serina Endopeptidasas/metabolismo , Regulación Alostérica , Sustitución de Aminoácidos , Animales , Anticuerpos Neutralizantes/química , Anticuerpos Neutralizantes/genética , Anticuerpos Neutralizantes/metabolismo , Especificidad de Anticuerpos , Antineoplásicos/química , Antineoplásicos/metabolismo , Sitios de Unión de Anticuerpos , Dominio Catalítico , Línea Celular Tumoral , Mapeo Epitopo , Serina Peptidasa A1 que Requiere Temperaturas Altas , Humanos , Fragmentos Fab de Inmunoglobulinas/química , Fragmentos Fab de Inmunoglobulinas/genética , Fragmentos Fab de Inmunoglobulinas/metabolismo , Fragmentos Fab de Inmunoglobulinas/farmacología , Inmunoglobulina G/química , Inmunoglobulina G/genética , Inmunoglobulina G/metabolismo , Inmunoglobulina G/farmacología , Melanoma/enzimología , Melanoma/metabolismo , Ratones , Proteínas Mutantes/química , Proteínas Mutantes/metabolismo , Proteínas Mutantes/farmacología , Proteínas de Neoplasias/química , Proteínas de Neoplasias/genética , Proteínas de Neoplasias/metabolismo , Fragmentos de Péptidos/química , Fragmentos de Péptidos/genética , Fragmentos de Péptidos/metabolismo , Fragmentos de Péptidos/farmacología , Inhibidores de Proteasas/química , Inhibidores de Proteasas/metabolismo , Subunidades de Proteína/antagonistas & inhibidores , Subunidades de Proteína/química , Subunidades de Proteína/genética , Subunidades de Proteína/metabolismo , Proteínas Recombinantes/química , Proteínas Recombinantes/metabolismo , Proteínas Recombinantes/farmacología , Serina Endopeptidasas/química , Serina Endopeptidasas/genética
3.
PLoS One ; 10(6): e0127693, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-26029890

RESUMEN

There is interest in large-scale and unbiased monitoring of biodiversity status and trend, but there are few published examples of such monitoring being implemented. The New Zealand Department of Conservation is implementing a monitoring program that involves sampling selected biota at the vertices of an 8-km grid superimposed over the 8.6 million hectares of public conservation land that it manages. The introduced brushtail possum (Trichosurus Vulpecula) is a major threat to some biota and is one taxon that they wish to monitor and report on. A pilot study revealed that the traditional method of monitoring possums using leg-hold traps set for two nights, termed the Trap Catch Index, was a constraint on the cost and logistical feasibility of the monitoring program. A phased implementation of the monitoring program was therefore conducted to collect data for evaluating the trade-off between possum occupancy-abundance estimates and the costs of sampling for one night rather than two nights. Reducing trapping effort from two nights to one night along four trap-lines reduced the estimated costs of monitoring by 5.8% due to savings in labour, food and allowances; it had a negligible effect on estimated national possum occupancy but resulted in slightly higher and less precise estimates of relative possum abundance. Monitoring possums for one night rather than two nights would provide an annual saving of NZ$72,400, with 271 fewer field days required for sampling. Possums occupied 60% (95% credible interval; 53-68) of sampling locations on New Zealand's public conservation land, with a mean relative abundance (Trap Catch Index) of 2.7% (2.0-3.5). Possum occupancy and abundance were higher in forest than in non-forest habitats. Our case study illustrates the need to evaluate relationships between sampling design, cost, and occupancy-abundance estimates when designing and implementing large-scale occupancy-abundance monitoring programs.


Asunto(s)
Conservación de los Recursos Naturales/economía , Análisis Costo-Beneficio , Especies Introducidas , Trichosurus/fisiología , Animales , Australia , Biodiversidad , Geografía , Nueva Zelanda , Proyectos Piloto
4.
Mar Pollut Bull ; 76(1-2): 16-27, 2013 Nov 15.
Artículo en Inglés | MEDLINE | ID: mdl-24054784

RESUMEN

The European Marine Strategy Framework Directive (MSFD) requires EU Member States (MS) to achieve Good Environmental Status (GEnS) of their seas by 2020. We address the question of what GEnS entails especially with regard to the level at which targets are set (descriptors, criteria, indicators), to scales for assessments (regional, sub-divisions, site-specific), and to difficulties in putting into practice the GEnS concept. We propose a refined and operational definition of GEnS, indicating the data and information needed to all parts of that definition. We indicate the options for determining when GEnS has been met, acknowledge the data and information needs for each option, and recommend a combination of existing quantitative targets and expert judgement. We think that the MSFD implementation needs to be less complex than shown for other similar directives, can be based largely on existing data and can be centred on the activities of the Regional Seas Conventions.


Asunto(s)
Conservación de los Recursos Naturales , Ecosistema , Contaminación del Agua/estadística & datos numéricos , Monitoreo del Ambiente , Política Ambiental , Océanos y Mares , Contaminación del Agua/prevención & control
5.
Mar Pollut Bull ; 64(8): 1564-79, 2012 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-22705072

RESUMEN

The construction of a new generation of coastal power stations in the UK and other western European countries has highlighted the absence of robust standards for thermal discharges to transitional and coastal waters. The proposed discharge volumes are greater than hitherto, yet there has been little independent critical examination of their potential impact, whilst much of the existing guidance has been adapted from freshwater practice. This review considers the available knowledge on the tolerance and behaviour of fish and other marine biota to heated effluents. Appropriate ways are suggested of grouping fish species to reflect their sensitivity to thermal effects. The plethora of existing standards are considered and their validity assessed in a framework of predicted seawater temperature rise. Those species or groups of organisms most likely to be affected are identified and finally specific recommendations for thermal standards consistent with long term sustainability are proposed.


Asunto(s)
Organismos Acuáticos/fisiología , Calor/efectos adversos , Agua de Mar/química , Calidad del Agua/normas , Adaptación Fisiológica , Animales , Peces , Calentamiento Global
6.
Mar Pollut Bull ; 62(2): 215-26, 2011 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-21215974

RESUMEN

Ever increasing and diverse use of the marine environment is leading to human-induced changes in marine life, habitats and landscapes, making necessary the development of marine policy that considers all members of the user community and addresses current, multiple, interacting uses. Taking a systems approach incorporating an understanding of The Ecosystem Approach, we integrate the DPSIR framework with ecosystem services and societal benefits, and the focus this gives allows us to create a specific framework for supporting decision making in the marine environment. Based on a linking of these three concepts, we present a set of basic postulates for the management of the marine environment and emphasise that these postulates should hold for marine management to be achieved. We illustrate these concepts using two case studies: the management of marine aggregates extraction in UK waters and the management of marine biodiversity at Flamborough Head, UK.


Asunto(s)
Conservación de los Recursos Naturales/métodos , Ecosistema , Ambiente , Análisis de Sistemas , Biodiversidad , Política Ambiental , Océanos y Mares , Medio Social , Reino Unido
7.
Mar Pollut Bull ; 60(12): 2175-86, 2010 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-20965524

RESUMEN

Through implementing environmental Directives, Europe has moved towards coordinated and integrated catchment-to-coast management, following the most novel legislation on ecosystem-based approaches worldwide. The novel joint synthesis of this direction reviewed here allows us to regard the Water Framework Directive (WFD) as a 'deconstructing structural approach' whereas the Marine Strategy Framework Directive (MSFD) is a 'holistic functional approach', i.e. the WFD has split the ecosystem into several biological quality elements, then it compares the structure of these (such as species complement) individually before combining them and attempting to determine the overall condition. In contrast the MSFD concentrates on the set of 11 descriptors which together summarize the way in which the whole system functions. We emphasize that both Directives are frameworks on which many other directives are linked but that they need to be fully and seamlessly integrated to give a land to open sea system of assessment and management. Hence, by taking account of the experience gained in the WFD implementation, together with that from regional sea conventions, such as OSPAR (North East Atlantic) or HELCOM (Baltic Sea), we propose in this contribution an integrative approach for the environmental status assessment, within the MSFD.


Asunto(s)
Conservación de los Recursos Naturales/métodos , Política Ambiental/legislación & jurisprudencia , Integración de Sistemas , Contaminación del Agua/prevención & control , Ecosistema , Monitoreo del Ambiente , Unión Europea , Océanos y Mares , Contaminación del Agua/legislación & jurisprudencia
8.
Sci Total Environ ; 408(19): 4007-19, 2010 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-20557924

RESUMEN

The European Water Framework Directive (WFD), which was adopted in 2000, changed water management in all member states of the European Union fundamentally, putting aquatic ecology at the base of management decisions. Here we review the successes and problems encountered with implementation of the WFD over the past 10years and provide recommendations to further improve the implementation process. We particularly address three fields: (i) the development of assessment methods (including reference conditions, typologies and intercalibration); (ii) the implementation of assessment systems in monitoring programmes; and (iii) the consequences for river basin management plans (such as the design, monitoring and success of restoration measures). The development of assessment methods has been a transparent process and has resulted in improved and more standardised tools for assessing water bodies across Europe. The process has been more time consuming, and methods are more complex, than originally expected. Future challenges still remain, including the estimation of uncertainty of assessment results and a revision of rules in combining the results obtained with different Biological Quality Elements. A huge amount of monitoring data is now being generated for WFD purposes. Monitoring data are not centrally stored and thus poorly accessible for purposes beyond the WFD. Future challenges include enhanced data accessibility and the establishment of a Europe-wide central monitoring network of reference sites. The WFD river basin management plans base management decisions on the response of aquatic organisms to environmental stress. In contrast to the effects of degradation, the biotic response to restoration is less well-known and poorly predictable. The timescale of the WFD (obtaining good ecological status in all surface waters by 2027) is over-ambitious. Future challenges include long-term monitoring of restoration measures to understand the requirements for ecosystems to recover and prioritisation of measures according to re-colonisation potential.


Asunto(s)
Conservación de los Recursos Naturales/métodos , Regulación Gubernamental , Contaminación del Agua/legislación & jurisprudencia , Conservación de los Recursos Naturales/tendencias , Ambiente , Monitoreo del Ambiente/legislación & jurisprudencia , Monitoreo del Ambiente/métodos , Unión Europea , Agua Dulce , Contaminación del Agua/prevención & control , Contaminación del Agua/estadística & datos numéricos
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