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1.
Nat Ecol Evol ; 8(7): 1216-1223, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38831016

RESUMO

Although invasive alien species have long been recognized as a major threat to nature and people, until now there has been no comprehensive global review of the status, trends, drivers, impacts, management and governance challenges of biological invasions. The Intergovernmental Science-Policy Platform on Biodiversity and Ecosystem Services (IPBES) Thematic Assessment Report on Invasive Alien Species and Their Control (hereafter 'IPBES invasive alien species assessment') drew on more than 13,000 scientific publications and reports in 15 languages as well as Indigenous and local knowledge on all taxa, ecosystems and regions across the globe. Therefore, it provides unequivocal evidence of the major and growing threat of invasive alien species alongside ambitious but realistic approaches to manage biological invasions. The extent of the threat and impacts has been recognized by the 143 member states of IPBES who approved the summary for policymakers of this assessment. Here, the authors of the IPBES assessment outline the main findings of the IPBES invasive alien species assessment and highlight the urgency to act now.


Assuntos
Biodiversidade , Conservação dos Recursos Naturais , Espécies Introduzidas , Animais , Ecossistema
2.
Sci Data ; 11(1): 191, 2024 Feb 12.
Artigo em Inglês | MEDLINE | ID: mdl-38346970

RESUMO

Sub-Saharan Africa is under-represented in global biodiversity datasets, particularly regarding the impact of land use on species' population abundances. Drawing on recent advances in expert elicitation to ensure data consistency, 200 experts were convened using a modified-Delphi process to estimate 'intactness scores': the remaining proportion of an 'intact' reference population of a species group in a particular land use, on a scale from 0 (no remaining individuals) to 1 (same abundance as the reference) and, in rare cases, to 2 (populations that thrive in human-modified landscapes). The resulting bii4africa dataset contains intactness scores representing terrestrial vertebrates (tetrapods: ±5,400 amphibians, reptiles, birds, mammals) and vascular plants (±45,000 forbs, graminoids, trees, shrubs) in sub-Saharan Africa across the region's major land uses (urban, cropland, rangeland, plantation, protected, etc.) and intensities (e.g., large-scale vs smallholder cropland). This dataset was co-produced as part of the Biodiversity Intactness Index for Africa Project. Additional uses include assessing ecosystem condition; rectifying geographic/taxonomic biases in global biodiversity indicators and maps; and informing the Red List of Ecosystems.


Assuntos
Conservação dos Recursos Naturais , Ecossistema , Animais , Biodiversidade , Mamíferos , Vertebrados , Plantas , África
3.
Evol Med Public Health ; 11(1): 438-447, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38022797

RESUMO

Background and objectives: Pathogen avoidance is a fundamental motive that shapes many aspects of human behavior including bias against groups stereotypically linked to disease (e.g. immigrants, outgroup members). This link has only been examined in convenience samples and it is unknown how pathogen avoidance processes operate in populations experiencing prolonged and heightened pathogen threat such as healthcare professionals. We examined whether healthcare professionals demonstrate the same link between pathogen disgust and intergroup bias as has been documented among the general population. Methodology: Participants (N = 317; 210 healthcare professionals) were recruited using snowball sampling to take an online survey. Participants completed the Three Domain Disgust Scale to assess pathogen, sexual and moral disgust. Participants then rated their perceptions of a fictitious immigrant group ('Krasneeans') and the degree to which they endorsed group-binding moral values. Results: Compared to control participants, healthcare professionals reported lower levels of pathogen disgust, but not sexual or moral disgust. However, regardless of profession, higher pathogen disgust was associated with viewing Krasneeans as less likeable and more unclean. Additionally, regardless of profession, higher pathogen disgust was associated with greater endorsement of group-binding moral values, although healthcare professionals reported greater overall endorsement of group-binding moral values than did control participants. Conclusions and implications: Although healthcare professionals demonstrated lower levels of pathogen disgust, they nevertheless exhibited largely the same relationship between pathogen disgust and interpersonal biases as did control participants. One practical implication of this association is that pathogen avoidance motives may contribute to inequitable patient treatment in healthcare settings.

4.
RSC Adv ; 13(45): 31411-31425, 2023 Oct 26.
Artigo em Inglês | MEDLINE | ID: mdl-37901257

RESUMO

While immunotherapies have revolutionized treatment for other cancers, glioblastoma multiforme (GBM) patients have not shown similar positive responses. The limited response to immunotherapies is partly due to the unique challenges associated with the GBM tumor microenvironment (TME), which promotes resistance to immunotherapies, causing many promising therapies to fail. There is, therefore, an urgent need to develop strategies that make the TME immune permissive to promote treatment efficacy. Bioactive nano-delivery systems, in which the nanoparticle, due to its chemical composition, provides the pharmacological function, have recently emerged as an encouraging option for enhancing the efficacy of immunotherapeutics. These systems are designed to overcome immunosuppressive mechanisms in the TME to improve the efficacy of a therapy. This review will discuss different aspects of the TME and how they impede therapy success. Then, we will summarize recent developments in TME-modifying nanotherapeutics and the in vitro models utilized to facilitate these advances.

5.
Nanoscale Adv ; 4(12): 2671-2681, 2022 Jun 14.
Artigo em Inglês | MEDLINE | ID: mdl-36132292

RESUMO

The protein corona (PC) that forms on nanoparticles (NPs) after in vivo injection influences their biodistribution, pharmacokinetics, and cell interaction. Although injected NPs traverse vascular networks, the impact of vascular features on the protein corona composition is mainly unexplored. Using an in vitro flow model that introduces bifurcations, a common feature of blood vessels, we show that vessels are not passive bystanders in the formation of the PC but that their features play active roles in defining the PC on NPs. The addition of bifurcation significantly increased the amount of proteins associated with NP. The bifurcation's introduction also changed the PC's composition on the NPs and affected the NP interactions with cells. Correlation analysis and modeling showed that these changes in the PC are mediated by both the branching and diameter reduction associated with vessel bifurcation and the resulting change in flow rate. The results indicate that blood vessel structures play an active part in the information of the PC, and their role should be studied critically for a better understanding of the PC and its biological implications.

6.
Biomaterials ; 257: 120232, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-32768727

RESUMO

Cell encapsulation is an attractive transplantation strategy to treat endocrine disorders. Transplanted cells offer a dynamic and stimulus-responsive system that secretes therapeutics based on patient need. Despite significant advancements, a challenge in allogeneic cell encapsulation is maintaining sufficient oxygen and nutrient exchange, while providing protection from the host immune system. To this end, we developed a subcutaneously implantable dual-reservoir encapsulation system integrating in situ prevascularization and local immunosuppressant delivery, termed NICHE. NICHE structure is 3D-printed in biocompatible polyamide 2200 and comprises of independent cell and drug reservoirs separated by a nanoporous membrane for sustained local release of immunosuppressant. Here we present the development and characterization of NICHE, as well as efficacy validation for allogeneic cell transplantation in an immunocompetent rat model. We established biocompatibility and mechanical stability of NICHE. Further, NICHE vascularization was achieved with the aid of mesenchymal stem cells. Our study demonstrated sustained local elution of immunosuppressant (CTLA4Ig) into the cell reservoir protected transcutaneously-transplanted allogeneic Leydig cells from host immune destruction during a 31-day study, and reduced systemic drug exposure by 12-fold. In summary, NICHE is the first encapsulation platform achieving both in situ vascularization and immunosuppressant delivery, presenting a viable strategy for allogeneic cell transplantation.


Assuntos
Transplante de Células-Tronco Hematopoéticas , Preparações Farmacêuticas , Animais , Encapsulamento de Células , Imunossupressores , Masculino , Ratos , Transplante Homólogo
7.
Sci Total Environ ; 747: 141006, 2020 Dec 10.
Artigo em Inglês | MEDLINE | ID: mdl-32768767

RESUMO

Many ecosystem services (ES) models exist to support sustainable development decisions. However, most ES studies use only a single modelling framework and, because of a lack of validation data, rarely assess model accuracy for the study area. In line with other research themes which have high model uncertainty, such as climate change, ensembles of ES models may better serve decision-makers by providing more robust and accurate estimates, as well as provide indications of uncertainty when validation data are not available. To illustrate the benefits of an ensemble approach, we highlight the variation between alternative models, demonstrating that there are large geographic regions where decisions based on individual models are not robust. We test if ensembles are more accurate by comparing the ensemble accuracy of multiple models for six ES against validation data across sub-Saharan Africa with the accuracy of individual models. We find that ensembles are better predictors of ES, being 5.0-6.1% more accurate than individual models. We also find that the uncertainty (i.e. variation among constituent models) of the model ensemble is negatively correlated with accuracy and so can be used as a proxy for accuracy when validation is not possible (e.g. in data-deficient areas or when developing scenarios). Since ensembles are more robust, accurate and convey uncertainty, we recommend that ensemble modelling should be more widely implemented within ES science to better support policy choices and implementation.


Assuntos
Mudança Climática , Ecossistema , Incerteza
8.
J Environ Manage ; 261: 110171, 2020 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-32148262

RESUMO

Invasive alien species (IAS) are known to pose a serious threat to biodiversity, and reduce the ability of ecosystems to provide benefits to humans. In recognition of this threat and to address the impacts of IAS, Parties to the Convention on Biological Diversity (CBD) adopted Aichi Biodiversity Target 9, which is dedicated to the control or eradication of priority IAS and the management of their introduction pathways by 2020. The achievement of Target 9 relies strongly on the commitment and ability of Parties to set ambitious national or regional targets and achive them, the availability of information and the requisite expertise on invasion biology. Now that the global community is gearing for the post-2020 Biodiversity Framework, it is time to take stock and identify opportunities to improve the performance of the African region beyond 2020. We approached this task by reviewing information on the impacts of IAS on ecosystem services in Africa, as a large proportion of Africans directly rely on ecosystem services, particularly in rural areas. Furthermore, we assessed the expertise on IAS in Africa. Our data sources were National Reports of African countries to the CBD, as well as peer-reviewed scientific literature. National Reports under the CBD provide information on measures taken to implement the Convention at country level, as well as progress towards the achievement of set targets. We found National Reports for 48 (about 90%) countries of which 73% provided feedback on IAS indicating commitment to fight IAS. However, there were few studies within peer-reviewed scientific literature looking at impacts of IAS on ecosystem services in Africa and almost half of the authors were non-Africans. This alludes to limited scientific expertise to inform and support IAS management on the continent. Both the National Reports and scientific literature showed that provisioning services were the most negatively affected by IAS. Also, more than 100 species were listed as problematic. More efforts and resources are needed to document IAS impacts across different realms (e.g. marine, terrestrial and freshwater) and for sub-regional bodies so that more integrated strategies and approaches can be developed. This information is also needed to support the development and implementation of national legislative and regulatory initiatives, as well as to report on international obligations such as the Aichi Biodiversity Targets.


Assuntos
Ecossistema , Espécies Introduzidas , África , Biodiversidade , Conservação dos Recursos Naturais , Água Doce , Humanos
9.
Trends Ecol Evol ; 34(1): 57-68, 2019 01.
Artigo em Inglês | MEDLINE | ID: mdl-30514580

RESUMO

Global biodiversity targets have far-reaching implications for nature conservation worldwide. Scenarios and models hold unfulfilled promise for ensuring such targets are well founded and implemented; here, we review how they can and should inform the Aichi Targets of the Strategic Plan for Biodiversity and their reformulation. They offer two clear benefits: providing a scientific basis for the wording and quantitative elements of targets; and identifying synergies and trade-offs by accounting for interactions between targets and the actions needed to achieve them. The capacity of scenarios and models to address complexity makes them invaluable for developing meaningful targets and policy, and improving conservation outcomes.


Assuntos
Biodiversidade , Conservação dos Recursos Naturais/métodos , Conservação dos Recursos Naturais/estatística & dados numéricos , Modelos Teóricos
10.
Am J Obstet Gynecol ; 186(3): 523-30, 2002 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-11904618

RESUMO

OBJECTIVE: We tested the hypothesis that intrauterine bacterial inoculation induces labor via expression of the inflammatory cytokine interleukin-1 (IL-1) in a murine model. STUDY DESIGN: Pregnant mice on day 14.5 of a 19-20 day gestation were inoculated with killed Escherichia coli or sterile media into either (a) the right uterine horn, (b) the right uterine horn following its surgical isolation from the contralateral horn and cervix, or (c) the kidney. Cytokine levels in gestational tissues and maternal serum were determined by use of enzyme-linked immunosorbent assay (ELISA). In a separate experiment, bacterially induced preterm delivery was compared between mice lacking a functional IL-1 receptor and wild-type control litter mates. RESULTS: Killed E coli induced delivery within 48 hours with similar dose-response curves regardless of inoculation site (intact uterine horn, isolated uterine horn, or kidney). Bacterial inoculation of an isolated right horn caused dramatic increases in local expression of IL-1 and IL-6. However, delivery occurred from the uninjected horn without corresponding upregulation of cytokines, with the exception of a modest rise within fetal membranes. Mice lacking a functional IL-1 receptor were no different from wild-type mice in their susceptibility to bacterially induced delivery. CONCLUSION: Bacterially induced labor in the murine model does not require IL-1 signaling.


Assuntos
Infecções por Escherichia coli/complicações , Interleucina-1/fisiologia , Trabalho de Parto Prematuro/microbiologia , Prenhez/fisiologia , Transdução de Sinais/fisiologia , Animais , Citocinas/metabolismo , Feminino , Mediadores da Inflamação/metabolismo , Camundongos , Camundongos Knockout/genética , Gravidez , Receptores de Interleucina-1/deficiência , Receptores de Interleucina-1/genética , Útero/metabolismo
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