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1.
Trends Ecol Evol ; 39(3): 258-266, 2024 03.
Artículo en Inglés | MEDLINE | ID: mdl-38114338

RESUMEN

Atoll islands are often perceived as inevitably lost due to rising sea levels. However, unlike other islands, atoll islands are dynamic landforms that have evolved, at least historically, to vertically accrete at a pace commensurate with changing sea levels. Rather than atoll islands' low elevation per se, the impairment of natural accretion processes is jeopardising their persistence. While global marine impacts are deteriorating coral reefs, local impacts also significantly affect accretion, together potentially tipping the scales toward atoll island erosion. Maintaining atoll island accretion requires intact sediment generation on coral reefs, unobstructed sediment transport from reef to island, and available vegetated deposition sites on the island. Ensuring the persistence of atoll islands must include global greenhouse gas emission reduction and local restoration of accretion processes.


Asunto(s)
Antozoos , Resiliencia Psicológica , Animales , Arrecifes de Coral
2.
Proc Natl Acad Sci U S A ; 120(16): e2214574120, 2023 04 18.
Artículo en Inglés | MEDLINE | ID: mdl-37036988

RESUMEN

The global loss of biodiversity has inspired actions to restore nature across the planet. Translocation and social attraction actions deliberately move or lure a target species to a restoration site to reintroduce or augment populations and enhance biodiversity and ecosystem resilience. Given limited conservation funding and rapidly accelerating extinction trajectories, tracking progress of these interventions can inform best practices and advance management outcomes. Seabirds are globally threatened and commonly targeted for translocation and social attraction ("active seabird restoration"), yet no framework exists for tracking these efforts nor informing best practices. This study addresses this gap for conservation decision makers responsible for seabirds and coastal management. We systematically reviewed active seabird restoration projects worldwide and collated results into a publicly accessible Seabird Restoration Database. We describe global restoration trends, apply a systematic process to measure success rates and response times since implementation, and examine global factors influencing outcomes. The database contains 851 active restoration events in 551 locations targeting 138 seabird species; 16% of events targeted globally threatened taxa. Visitation occurred in 80% of events and breeding occurred in 76%, on average 2 y after implementation began (SD = 3.2 y). Outcomes varied by taxonomy, with the highest and quickest breeding response rates for Charadriiformes (terns, gulls, and auks), primarily with social attraction. Given delayed and variable response times to active restoration, 5 y is appropriate before evaluating outcomes. The database and results serve as a model for tracking and evaluating restoration outcomes, and is applicable to measuring conservation interventions for additional threatened taxa.


Asunto(s)
Charadriiformes , Restauración y Remediación Ambiental , Animales , Conservación de los Recursos Naturales , Extinción Biológica , Internacionalidad , Cruzamiento , Ecosistema , Bases de Datos Factuales
3.
Proc Natl Acad Sci U S A ; 119(51): e2122354119, 2022 12 20.
Artículo en Inglés | MEDLINE | ID: mdl-36508667

RESUMEN

Islands support unique plants, animals, and human societies found nowhere else on the Earth. Local and global stressors threaten the persistence of island ecosystems, with invasive species being among the most damaging, yet solvable, stressors. While the threat of invasive terrestrial mammals on island flora and fauna is well recognized, recent studies have begun to illustrate their extended and destructive impacts on adjacent marine environments. Eradication of invasive mammals and restoration of native biota are promising tools to address both island and ocean management goals. The magnitude of the marine benefits of island restoration, however, is unlikely to be consistent across the globe. We propose a list of six environmental characteristics most likely to affect the strength of land-sea linkages: precipitation, elevation, vegetation cover, soil hydrology, oceanographic productivity, and wave energy. Global databases allow for the calculation of comparable metrics describing each environmental character across islands. Such metrics can be used today to evaluate relative potential for coupled land-sea conservation efforts and, with sustained investment in monitoring on land and sea, can be used in the future to refine science-based planning tools for integrated land-sea management. As conservation practitioners work to address the effects of climate change, ocean stressors, and biodiversity crises, it is essential that we maximize returns from our management investments. Linking efforts on land, including eradication of island invasive mammals, with marine restoration and protection should offer multiplied benefits to achieve concurrent global conservation goals.


Asunto(s)
Conservación de los Recursos Naturales , Ecosistema , Animales , Humanos , Biodiversidad , Especies Introducidas , Cambio Climático , Mamíferos
4.
Sci Rep ; 12(1): 13391, 2022 08 10.
Artículo en Inglés | MEDLINE | ID: mdl-35948555

RESUMEN

Islands are global hotspots for biodiversity and extinction, representing ~ 5% of Earth's land area alongside 40% of globally threatened vertebrates and 61% of global extinctions since the 1500s. Invasive species are the primary driver of native biodiversity loss on islands, though eradication of invasive species from islands has been effective at halting or reversing these trends. A global compendium of this conservation tool is essential for scaling best-practices and enabling innovations to maximize biodiversity outcomes. Here, we synthesize over 100 years of invasive vertebrate eradications from islands, comprising 1550 eradication attempts on 998 islands, with an 88% success rate. We show a significant growth in eradication activity since the 1980s, primarily driven by rodent eradications. The annual number of eradications on islands peaked in the mid-2000s, but the annual area treated continues to rise dramatically. This trend reflects increases in removal efficacy and project complexity, generating increased conservation gains. Our synthesis demonstrates the collective contribution of national interventions towards global biodiversity outcomes. Further investment in invasive vertebrate eradications from islands will expand biodiversity conservation while strengthening biodiversity resilience to climate change and creating co-benefits for human societies.


Asunto(s)
Biodiversidad , Conservación de los Recursos Naturales , Animales , Cambio Climático , Humanos , Especies Introducidas , Vertebrados
5.
Ecol Appl ; 32(8): e2694, 2022 12.
Artículo en Inglés | MEDLINE | ID: mdl-35708073

RESUMEN

Advances in artificial intelligence for computer vision hold great promise for increasing the scales at which ecological systems can be studied. The distribution and behavior of individuals is central to ecology, and computer vision using deep neural networks can learn to detect individual objects in imagery. However, developing supervised models for ecological monitoring is challenging because it requires large amounts of human-labeled training data, requires advanced technical expertise and computational infrastructure, and is prone to overfitting. This limits application across space and time. One solution is developing generalized models that can be applied across species and ecosystems. Using over 250,000 annotations from 13 projects from around the world, we develop a general bird detection model that achieves over 65% recall and 50% precision on novel aerial data without any local training despite differences in species, habitat, and imaging methodology. Fine-tuning this model with only 1000 local annotations increases these values to an average of 84% recall and 69% precision by building on the general features learned from other data sources. Retraining from the general model improves local predictions even when moderately large annotation sets are available and makes model training faster and more stable. Our results demonstrate that general models for detecting broad classes of organisms using airborne imagery are achievable. These models can reduce the effort, expertise, and computational resources necessary for automating the detection of individual organisms across large scales, helping to transform the scale of data collection in ecology and the questions that can be addressed.


Asunto(s)
Aprendizaje Profundo , Humanos , Animales , Ecosistema , Inteligencia Artificial , Redes Neurales de la Computación , Aves
6.
Sci Rep ; 11(1): 5395, 2021 03 08.
Artículo en Inglés | MEDLINE | ID: mdl-33686134

RESUMEN

Eleven years after invasive Norway rats (Rattus norvegicus) were eradicated from Hawadax Island, in the Aleutian Islands, Alaska, the predicted three-level trophic cascade in the rocky intertidal, with native shorebirds as the apex predator, returned, leading to a community resembling those on rat-free islands with significant decreases in invertebrate species abundances and increases in fleshy algal cover. Rats had indirectly structured the intertidal community via their role as the apex predator in a four-level trophic cascade. Our results are an excellent example of an achievable and relatively short-term community-level recovery following removal of invasive animals. These conservation successes are especially important for islands as their disproportionately high levels of native biodiversity are excessively threatened by invasive mammals.


Asunto(s)
Biodiversidad , Especies Introducidas , Alaska , Animales , Islas , Ratas
7.
Autism Adulthood ; 3(2): 195-203, 2021 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-36601467

RESUMEN

This article explores coproduction in relation to autistic people. We reflect on the coproduction process with autistic adults from the Authentistic Research Collective at University College London. We aimed to support the autistic population's mental health needs by coproducing a document on adapting psychological therapy, and by developing a set of reflective guidelines to guide and encourage future coproduction initiatives between autistic and nonautistic team members. We reflect upon six elements that are of potential importance for future coproduction projects with autistic adults: (1) the meaning of coproduction; (2) ground rules and a traffic light system; (3) environmental adaptations; (4) digital communication tools; (5) encouraging authenticity; and (6) supporting autistic strengths. We conclude by discussing future research avenues into optimizing coproduction with autistic people, and how such research may influence both practice and policy. Lay summary: Why is coproduction important?: Coproduction means creating things jointly with others. Ideally, autistic people should be involved in research that is about them so that their thoughts and opinions are included. Coproduction allows this to happen.What is the purpose of this article?: There is little advice for how autistic and nonautistic people can work together to coproduce useful research. This article hopes to encourage discussion by sharing our reflections on how we used coproduction in our project.What did we do?: Our group was made up of autistic and nonautistic people. One of our goals was to gain experience in using coproduction. We created this article containing our reflections-what we found worked well, and what we felt could be done differently in the future.What did we learn?: We learnt the importance of five key areas: (1) group rules, and a "traffic light" system to help group members show how they like to communicate; (2) adapting the environment to suit people's needs; (3) inclusion of digital communication tools; (4) encouraging group members to feel they are authentic (be fully themselves); and (5) supporting autistic strengths. We hope that the discussion of these themes will be helpful for future coproduction projects.

8.
J Addict ; 2020: 3427270, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32547803

RESUMEN

Constraint theory (Hammersley, 2014) offers a novel way of understanding addiction as a lack of cognitive, behavioural, and social constraints on substance use. Here, cannabis constraints were studied in a large online opportunity sample: N = 302; 205 men, 97 women. Age ranged from 14 to 60 years (mean = 25, SD = 8.0). Most participants were from UK or North America. Participants completed a questionnaire assessing 15 cannabis constraints and standard self-report frequency measures of drug use. Factor analysis of the constraint questionnaire found 15 factors, similar to those proposed theoretically. These factors could discriminate well between past and current users and heavy and light users. The best discriminator was concerns about the possibility of becoming addicted; the less concerned the heavier was use, although those who actually felt addicted were more concerned than others. Past users also constrained due to using legal highs instead, concerns about illegality, and using only when others used. Light users constrained due to availability and cost issues, as well as unpleasant effects. These findings suggest that there is utility in constraint theory and that heavy use occurs due to a relative lack of constraints.

9.
PLoS One ; 14(3): e0212128, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-30917126

RESUMEN

Invasive alien species are a major threat to native insular species. Eradicating invasive mammals from islands is a feasible and proven approach to prevent biodiversity loss. We developed a conceptual framework to identify globally important islands for invasive mammal eradications to prevent imminent extinctions of highly threatened species using biogeographic and technical factors, plus a novel approach to consider socio-political feasibility. We applied this framework using a comprehensive dataset describing the distribution of 1,184 highly threatened native vertebrate species (i.e. those listed as Critically Endangered or Endangered on the IUCN Red List) and 184 non-native mammals on 1,279 islands worldwide. Based on extinction risk, irreplaceability, severity of impact from invasive species, and technical feasibility of eradication, we identified and ranked 292 of the most important islands where eradicating invasive mammals would benefit highly threatened vertebrates. When socio-political feasibility was considered, we identified 169 of these islands where eradication planning or operation could be initiated by 2020 or 2030 and would improve the survival prospects of 9.4% of the Earth's most highly threatened terrestrial insular vertebrates (111 of 1,184 species). Of these, 107 islands were in 34 countries and territories and could have eradication projects initiated by 2020. Concentrating efforts to eradicate invasive mammals on these 107 islands would benefit 151 populations of 80 highly threatened vertebrates and make a major contribution towards achieving global conservation targets adopted by the world's nations.


Asunto(s)
Conservación de los Recursos Naturales/métodos , Especies Introducidas/tendencias , Animales , Biodiversidad , Especies en Peligro de Extinción , Extinción Biológica , Islas , Mamíferos
10.
Gene Ther ; 26(1-2): 40-56, 2019 02.
Artículo en Inglés | MEDLINE | ID: mdl-30514969

RESUMEN

We report the restoration of euglycaemia in chemically induced diabetic C57BL/6 mice and spontaneously diabetic Non Obese Diabetic (NOD) mice by intravenous systemic administration of a single-stranded adeno-associated virus (ssAAV2/8) codon optimised (co) vector encoding furin cleavable human proinsulin under a liver-specific promoter. There were no immunological barriers to efficacy of insulin gene therapy in chemically induced C57BL/6 mice, which enjoyed long-lasting correction of hyperglycaemia after therapy, up to 250 days. Euglycaemia was also restored in spontaneously diabetic NOD mice, although these mice required a 7-10-fold higher dose of vector to achieve similar efficacy as the C57BL/6 mice and the immunodeficient NODscid mice. We detected CD8+ T cell reactivity to insulin and mild inflammatory infiltration in the livers of gene therapy recipient NOD mice, neither of which were observed in the treated C57BL/6 mice. Efficacy of the gene therapy in NOD mice was partially improved by targeting the immune system with anti-CD4 antibody treatment, while transfer of NOD mouse AAV2/8-reactive serum to recipients prevented successful restoration of euglycaemia in AAV2/8-HLP-hINSco-treated NODscid mice. Our data indicate that both immune cells and antibodies form a barrier to successful restoration of euglycaemia in autoimmune diabetic recipient mice with insulin gene therapy, but that this barrier can be overcome by increasing the dose of vector and by suppressing immune responses.


Asunto(s)
Dependovirus/inmunología , Diabetes Mellitus Experimental/terapia , Terapia Genética/efectos adversos , Terapia de Inmunosupresión/métodos , Insulina/inmunología , Animales , Antígenos CD4/inmunología , Dependovirus/genética , Terapia Genética/métodos , Células HEK293 , Humanos , Insulina/genética , Hígado/inmunología , Masculino , Ratones , Ratones Endogámicos C57BL , Ratones Endogámicos NOD , Ratones SCID , Linfocitos T/inmunología
12.
PLoS One ; 13(7): e0200743, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-30016347

RESUMEN

Rat eradication has become a common conservation intervention in island ecosystems and its effectiveness in protecting native vertebrates is increasingly well documented. Yet, the impacts of rat eradication on plant communities remain poorly understood. Here we compare native and non-native tree and palm seedling abundance before and after eradication of invasive rats (Rattus rattus) from Palmyra Atoll, Line Islands, Central Pacific Ocean. Overall, seedling recruitment increased for five of the six native trees species examined. While pre-eradication monitoring found no seedlings of Pisonia grandis, a dominant tree species that is important throughout the Pacific region, post-eradication monitoring documented a notable recruitment event immediately following eradication, with up to 688 individual P. grandis seedlings per 100m2 recorded one month post-eradication. Two other locally rare native trees with no observed recruitment in pre-eradication surveys had recruitment post-rat eradication. However, we also found, by five years post-eradication, a 13-fold increase in recruitment of the naturalized and range-expanding coconut palm Cocos nucifera. Our results emphasize the strong effects that a rat eradication can have on tree recruitment with expected long-term effects on canopy composition. Rat eradication released non-native C. nucifera, likely with long-term implications for community composition, potentially necessitating future management interventions. Eradication, nevertheless, greatly benefitted recruitment of native tree species. If this pattern persists over time, we expect long-term benefits for flora and fauna dependent on these native species.


Asunto(s)
Cocos/fisiología , Conservación de los Recursos Naturales , Ecosistema , Especies Introducidas , Árboles/fisiología , Animales , Biodiversidad , Ecología , Hawaii , Islas , Océano Pacífico , Ratas , Plantones , Clima Tropical
13.
Sci Adv ; 3(10): e1603080, 2017 10.
Artículo en Inglés | MEDLINE | ID: mdl-29075662

RESUMEN

Global biodiversity loss is disproportionately rapid on islands, where invasive species are a major driver of extinctions. To inform conservation planning aimed at preventing extinctions, we identify the distribution and biogeographic patterns of highly threatened terrestrial vertebrates (classified by the International Union for Conservation of Nature) and invasive vertebrates on ~465,000 islands worldwide by conducting a comprehensive literature review and interviews with more than 500 experts. We found that 1189 highly threatened vertebrate species (319 amphibians, 282 reptiles, 296 birds, and 292 mammals) breed on 1288 islands. These taxa represent only 5% of Earth's terrestrial vertebrates and 41% of all highly threatened terrestrial vertebrates, which occur in <1% of islands worldwide. Information about invasive vertebrates was available for 1030 islands (80% of islands with highly threatened vertebrates). Invasive vertebrates were absent from 24% of these islands, where biosecurity to prevent invasions is a critical management tool. On the 76% of islands where invasive vertebrates were present, management could benefit 39% of Earth's highly threatened vertebrates. Invasive mammals occurred in 97% of these islands, with Rattus sp. as the most common invasive vertebrate (78%; 609 islands). Our results provide an important baseline for identifying islands for invasive species eradication and other island conservation actions that reduce biodiversity loss.


Asunto(s)
Especies en Peligro de Extinción , Especies Introducidas , Vertebrados , Animales , Biodiversidad , Cruzamiento , Conservación de los Recursos Naturales , Ecosistema , Extinción Biológica , Geografía , Humanos , Islas , Vertebrados/clasificación
14.
Conserv Biol ; 31(5): 986-1001, 2017 10.
Artículo en Inglés | MEDLINE | ID: mdl-28151557

RESUMEN

Artificial lights at night cause high mortality of seabirds, one of the most endangered groups of birds globally. Fledglings of burrow-nesting seabirds, and to a lesser extent adults, are attracted to and then grounded (i.e., forced to land) by lights when they fly at night. We reviewed the current state of knowledge of seabird attraction to light to identify information gaps and propose measures to address the problem. Although species in families such as Alcidae and Anatidae can be grounded by artificial light, the most affected seabirds are petrels and shearwaters (Procellariiformes). At least 56 species of Procellariiformes, more than one-third of them (24) threatened, are subject to grounding by lights. Seabirds grounded by lights have been found worldwide, mainly on oceanic islands but also at some continental locations. Petrel breeding grounds confined to formerly uninhabited islands are particularly at risk from light pollution due to tourism and urban sprawl. Where it is impractical to ban external lights, rescue programs of grounded birds offer the most immediate and employed mitigation to reduce the rate of light-induced mortality and save thousands of birds every year. These programs also provide useful information for seabird management. However, these data are typically fragmentary, biased, and uncertain and can lead to inaccurate impact estimates and poor understanding of the phenomenon of seabird attraction to lights. We believe the most urgently needed actions to mitigate and understand light-induced mortality of seabirds are estimation of mortality and effects on populations; determination of threshold light levels and safe distances from light sources; documentation of the fate of rescued birds; improvement of rescue campaigns, particularly in terms of increasing recovery rates and level of care; and research on seabird-friendly lights to reduce attraction.


Asunto(s)
Aves , Conservación de los Recursos Naturales , Luz , Animales , Planificación Ambiental , Contaminación Ambiental , Islas , Mortalidad , Océanos y Mares
15.
Am J Trop Med Hyg ; 96(3): 749-757, 2017 03.
Artículo en Inglés | MEDLINE | ID: mdl-28138052

RESUMEN

Many neglected tropical zoonotic pathogens are maintained by introduced mammals, and on islands the most common introduced species are rodents, cats, and dogs. Management of introduced mammals, including control or eradication of feral populations, which is frequently done for ecological restoration, could also reduce or eliminate the pathogens these animals carry. Understanding the burden of these zoonotic diseases is crucial for quantifying the potential public health benefits of introduced mammal management. However, epidemiological data are only available from a small subset of islands where these introduced mammals co-occur with people. We examined socioeconomic and climatic variables as predictors for disease burdens of angiostrongyliasis, leptospirosis, toxoplasmosis, toxocariasis, and rabies from 57 islands or island countries. We found strong correlates of disease burden for leptospirosis, Toxoplasma gondii infection, angiostrongyliasis, and toxocariasis with more than 50% of the variance explained, and an average of 57% (range = 32-95%) predictive accuracy on out-of-sample data. We used these relationships to provide estimates of leptospirosis incidence and T. gondii seroprevalence infection on islands where nonnative rodents and cats are present. These predicted estimates of disease burden could be used in an initial assessment of whether the costs of managing introduced mammal reservoirs might be less than the costs of perpetual treatment of these diseases on islands.


Asunto(s)
Leptospirosis/epidemiología , Rabia/epidemiología , Infecciones por Strongylida/epidemiología , Toxocariasis/epidemiología , Toxoplasmosis Animal/epidemiología , Zoonosis/epidemiología , Animales , Animales Salvajes/parasitología , Animales Salvajes/virología , Humanos , Incidencia , Islas , Leptospirosis/veterinaria , Mamíferos/parasitología , Mamíferos/virología , Salud Pública , Rabia/veterinaria , Estudios Seroepidemiológicos , Factores Socioeconómicos , Infecciones por Strongylida/veterinaria , Zoonosis/parasitología , Zoonosis/virología
16.
Nat Commun ; 7: 12488, 2016 08 18.
Artículo en Inglés | MEDLINE | ID: mdl-27535095

RESUMEN

Invasive mammals on islands pose severe, ongoing threats to global biodiversity. However, the severity of threats from different mammals, and the role of interacting biotic and abiotic factors in driving extinctions, remain poorly understood at a global scale. Here we model global extirpation patterns for island populations of threatened and extinct vertebrates. Extirpations are driven by interacting factors including invasive rats, cats, pigs, mustelids and mongooses, native species taxonomic class and volancy, island size, precipitation and human presence. We show that controlling or eradicating the relevant invasive mammals could prevent 41-75% of predicted future extirpations. The magnitude of benefits varies across species and environments; for example, managing invasive mammals on small, dry islands could halve the extirpation risk for highly threatened birds and mammals, while doing so on large, wet islands may have little benefit. Our results provide quantitative estimates of conservation benefits and, when combined with costs in a return-on-investment framework, can guide efficient conservation strategies.


Asunto(s)
Especies en Peligro de Extinción , Especies Introducidas , Mamíferos/fisiología , Animales , Gatos , Conservación de los Recursos Naturales , Extinción Biológica , Humanos , Islas , Modelos Biológicos , Oportunidad Relativa , Probabilidad , Lluvia , Ratas , Reproducibilidad de los Resultados , Factores de Riesgo , Especificidad de la Especie
17.
Proc Natl Acad Sci U S A ; 113(15): 4033-8, 2016 Apr 12.
Artículo en Inglés | MEDLINE | ID: mdl-27001852

RESUMEN

More than US$21 billion is spent annually on biodiversity conservation. Despite their importance for preventing or slowing extinctions and preserving biodiversity, conservation interventions are rarely assessed systematically for their global impact. Islands house a disproportionately higher amount of biodiversity compared with mainlands, much of which is highly threatened with extinction. Indeed, island species make up nearly two-thirds of recent extinctions. Islands therefore are critical targets of conservation. We used an extensive literature and database review paired with expert interviews to estimate the global benefits of an increasingly used conservation action to stem biodiversity loss: eradication of invasive mammals on islands. We found 236 native terrestrial insular faunal species (596 populations) that benefitted through positive demographic and/or distributional responses from 251 eradications of invasive mammals on 181 islands. Seven native species (eight populations) were negatively impacted by invasive mammal eradication. Four threatened species had their International Union for the Conservation of Nature (IUCN) Red List extinction-risk categories reduced as a direct result of invasive mammal eradication, and no species moved to a higher extinction-risk category. We predict that 107 highly threatened birds, mammals, and reptiles on the IUCN Red List-6% of all these highly threatened species-likely have benefitted from invasive mammal eradications on islands. Because monitoring of eradication outcomes is sporadic and limited, the impacts of global eradications are likely greater than we report here. Our results highlight the importance of invasive mammal eradication on islands for protecting the world's most imperiled fauna.


Asunto(s)
Conservación de los Recursos Naturales , Especies Introducidas , Mamíferos , Animales , Biodiversidad , Islas
19.
Diabetes ; 65(1): 120-8, 2016 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-26450994

RESUMEN

CTLA-4 is a critical "checkpoint" regulator in autoimmunity. Variation in CTLA-4 isoform expression has been linked to type 1 diabetes development in human and NOD mouse studies. In the NOD mouse, a causative link between increased expression of the minor isoform ligand-independent CTLA-4 and a reduction in diabetes has become widely accepted. Altered splicing of CTLA-4 has been attributed to a single nucleotide polymorphism (SNP) in Ctla4 exon2 (e2_77A/G). To investigate this link, we have used NOD embryonic stem (ES) cells to generate a novel NOD transgenic line with the 77A/G SNP. This strain phenocopies the increase in splicing toward the liCTLA4 isoform seen in B10 Idd5.1 mice. Crucially, the SNP does not alter the spontaneous incidence of diabetes, the incidence of cyclophosphamide-induced diabetes, or the activation of diabetogenic T-cell receptor transgenic CD4(+) T cells after adoptive transfer. Our results show that one or more of the many other linked genetic variants between the B10 and NOD genome are required for the diabetes protection conferred by Idd5.1. With the NOD mouse model closely mimicking the human disease, our data demonstrate that knock-in transgenic mice on the NOD background can test causative mutations relevant in human diabetes.


Asunto(s)
Autoinmunidad/genética , Linfocitos T CD4-Positivos/inmunología , Antígeno CTLA-4/genética , Diabetes Mellitus Tipo 1/genética , Empalme del ARN/genética , ARN Mensajero/metabolismo , Traslado Adoptivo , Animales , Autoinmunidad/inmunología , Antígeno CTLA-4/inmunología , Diabetes Mellitus Tipo 1/inmunología , Técnicas de Sustitución del Gen , Predisposición Genética a la Enfermedad , Ratones , Ratones Endogámicos NOD , Ratones Transgénicos , Células Madre Embrionarias de Ratones , Polimorfismo de Nucleótido Simple , Isoformas de Proteínas
20.
Conserv Biol ; 29(1): 133-42, 2015 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-25065901

RESUMEN

Protected area delineation and conservation action are urgently needed on marine islands, but the potential biodiversity benefits of these activities can be difficult to assess due to lack of species diversity information for lesser known taxa. We used linear mixed effects modeling and simple spatial analyses to investigate whether conservation activities based on the diversity of well-known insular taxa (birds and mammals) are likely to also capture the diversity of lesser known taxa (reptiles, amphibians, vascular land plants, ants, land snails, butterflies, and tenebrionid beetles). We assembled total, threatened, and endemic diversity data for both well-known and lesser known taxa and combined these with physical island biogeography characteristics for 1190 islands from 109 archipelagos. Among physical island biogeography factors, island area was the best indicator of diversity of both well-known and little-known taxa. Among taxonomic factors, total mammal species richness was the best indicator of total diversity of lesser known taxa, and the combination of threatened mammal and threatened bird diversity was the best indicator of lesser known endemic richness. The results of other intertaxon diversity comparisons were highly variable, however. Based on our results, we suggest that protecting islands above a certain minimum threshold area may be the most efficient use of conservation resources. For example, using our island database, if the threshold were set at 10 km(2) and the smallest 10% of islands greater than this threshold were protected, 119 islands would be protected. The islands would range in size from 10 to 29 km(2) and would include 268 lesser known species endemic to a single island, along with 11 bird and mammal species endemic to a single island. Our results suggest that for islands of equivalent size, prioritization based on total or threatened bird and mammal diversity may also capture opportunities to protect lesser known species endemic to islands.


Asunto(s)
Biodiversidad , Aves/fisiología , Conservación de los Recursos Naturales , Islas , Mamíferos/fisiología , Animales , Embryophyta/fisiología , Geografía , Invertebrados/fisiología , Modelos Lineales , Modelos Biológicos , Análisis Espacial , Vertebrados/fisiología
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