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1.
Anal Chem ; 94(25): 8966-8974, 2022 06 28.
Artigo em Inglês | MEDLINE | ID: mdl-35708243

RESUMO

Atmospheric particles and droplets contain numerous organic substances, some of which form complexes with metal ions, significantly affecting bulk physicochemical properties and chemical reactivity. However, the detection and identification of complexing agents and their corresponding metal complexes remains an analytical challenge. In this study, we developed an LC/HRMS nontarget screening (NTS) approach which allows the selective detection of complexing agents in aerosol particle extracts and rainwater. To achieve this, a T-junction is installed between the LC outlet and the ion source, and a FeCl3 solution is added for postcolumn complexation. The resulting mass spectra are screened for the three characteristic iron(III)-complexes [M - H + FeCl3]-, [M - 2H + FeCl2]-, and [M - 3H + FeCl]- with mass differences (Δm/z) between the complexing agent and the iron complex of 160.8416, 124.8648, and 89.8959, respectively. Up to 29 di- or tricarboxylic acids were identified as complexing agents in aerosol particle samples from two different sites (Melpitz, Germany, and Wangdu, China) at concentrations as low as 50 nM. Thirteen complexing agents were detected even in measurements without postcolumn iron addition from complexation with background Fe3+ traces from the analytical system. At least for the highest concentrated complexing agents, the proposed screening approach can thus be exploited in a NTS approach without any device modification. Besides carboxylic acids, 4-nitrophenol and 4-nitrocatechol were identified as further complexing agents, demonstrating the applicability of the approach to other matrices and to a range of different complexing agents.


Assuntos
Compostos Férricos , Ferro , Aerossóis , Ácidos Carboxílicos/química , Ferro/química , Espectrometria de Massas/métodos
2.
Mol Cancer ; 20(1): 69, 2021 04 15.
Artigo em Inglês | MEDLINE | ID: mdl-33858437

RESUMO

Synthetic mRNA provides a template for the synthesis of any given protein, protein fragment or peptide and lends itself to a broad range of pharmaceutical applications, including different modalities of cancer immunotherapy. With the ease of rapid, large scale Good Manufacturing Practice-grade mRNA production, mRNA is ideally poised not only for off-the shelf cancer vaccines but also for personalized neoantigen vaccination. The ability to stimulate pattern recognition receptors and thus an anti-viral type of innate immune response equips mRNA-based vaccines with inherent adjuvanticity. Nucleoside modification and elimination of double-stranded RNA can reduce the immunomodulatory activity of mRNA and increase and prolong protein production. In combination with nanoparticle-based formulations that increase transfection efficiency and facilitate lymphatic system targeting, nucleoside-modified mRNA enables efficient delivery of cytokines, costimulatory receptors, or therapeutic antibodies. Steady but transient production of the encoded bioactive molecule from the mRNA template can improve the pharmacokinetic, pharmacodynamic and safety properties as compared to the respective recombinant proteins. This may be harnessed for applications that benefit from a higher level of expression control, such as chimeric antigen receptor (CAR)-modified adoptive T-cell therapies. This review highlights the advancements in the field of mRNA-based cancer therapeutics, providing insights into key preclinical developments and the evolving clinical landscape.


Assuntos
Terapia Genética , Imunoterapia , Neoplasias/etiologia , Neoplasias/terapia , RNA Mensageiro/administração & dosagem , Animais , Anticorpos/genética , Anticorpos/imunologia , Apresentação de Antígeno/imunologia , Células Apresentadoras de Antígenos/imunologia , Células Apresentadoras de Antígenos/metabolismo , Antígenos de Neoplasias/genética , Antígenos de Neoplasias/imunologia , Biomarcadores Tumorais , Vacinas Anticâncer/administração & dosagem , Vacinas Anticâncer/genética , Vacinas Anticâncer/imunologia , Citocinas/metabolismo , Células Dendríticas/imunologia , Células Dendríticas/metabolismo , Terapia Genética/métodos , Humanos , Fatores Imunológicos/genética , Imunoterapia/métodos , Neoplasias/patologia , RNA Mensageiro/química , RNA Mensageiro/genética , RNA Mensageiro/imunologia , Receptores de Antígenos de Linfócitos T/genética , Receptores de Antígenos de Linfócitos T/imunologia , Linfócitos T/imunologia , Linfócitos T/metabolismo
3.
PLoS Biol ; 16(12): e2006841, 2018 12.
Artigo em Inglês | MEDLINE | ID: mdl-30513079

RESUMO

Human use of the land (for agriculture and settlements) has a substantial negative effect on biodiversity globally. However, not all species are adversely affected by land use, and indeed, some benefit from the creation of novel habitat. Geographically rare species may be more negatively affected by land use than widespread species, but data limitations have so far prevented global multi-clade assessments of land-use effects on narrow-ranged and widespread species. We analyse a large, global database to show consistent differences in assemblage composition. Compared with natural habitat, assemblages in disturbed habitats have more widespread species on average, especially in urban areas and the tropics. All else being equal, this result means that human land use is homogenizing assemblage composition across space. Disturbed habitats show both reduced abundances of narrow-ranged species and increased abundances of widespread species. Our results are very important for biodiversity conservation because narrow-ranged species are typically at higher risk of extinction than widespread species. Furthermore, the shift to more widespread species may also affect ecosystem functioning by reducing both the contribution of rare species and the diversity of species' responses to environmental changes among local assemblages.


Assuntos
Agricultura/métodos , Biodiversidade , Conservação dos Recursos Naturais/métodos , Animais , Ecossistema , Humanos , Recursos Naturais
4.
J Biol Chem ; 291(39): 20417-26, 2016 09 23.
Artigo em Inglês | MEDLINE | ID: mdl-27493205

RESUMO

Transglutaminase from Streptomyces mobaraensis (MTG) is an important enzyme for cross-linking and modifying proteins. An intrinsic substrate of MTG is the dispase autolysis-inducing protein (DAIP). The amino acid sequence of DAIP contains 5 potential glutamines and 10 lysines for MTG-mediated cross-linking. The aim of the study was to determine the structure and glutamine cross-linking sites of the first physiological MTG substrate. A production procedure was established in Escherichia coli BL21 (DE3) to obtain high yields of recombinant DAIP. DAIP variants were prepared by replacing four of five glutamines for asparagines in various combinations via site-directed mutagenesis. Incorporation of biotin cadaverine revealed a preference of MTG for the DAIP glutamines in the order of Gln-39 ≫ Gln-298 > Gln-345 ∼ Gln-65 ≫ Gln-144. In the structure of DAIP the preferred glutamines do cluster at the top of the seven-bladed ß-propeller. This suggests a targeted cross-linking of DAIP by MTG that may occur after self-assembly in the bacterial cell wall. Based on our biochemical and structural data of the first physiological MTG substrate, we further provide novel insight into determinants of MTG-mediated modification, specificity, and efficiency.


Assuntos
Proteínas de Bactérias/metabolismo , Streptomyces/metabolismo , Transglutaminases/metabolismo , Proteínas de Bactérias/química , Proteínas de Bactérias/genética , Escherichia coli/química , Escherichia coli/genética , Escherichia coli/metabolismo , Proteínas Recombinantes/química , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Streptomyces/química , Streptomyces/genética , Transglutaminases/química , Transglutaminases/genética
5.
Ecol Lett ; 19(9): 1009-22, 2016 09.
Artigo em Inglês | MEDLINE | ID: mdl-27358193

RESUMO

We introduce a novel framework for conceptualising, quantifying and unifying discordant patterns of species richness along geographical gradients. While not itself explicitly mechanistic, this approach offers a path towards understanding mechanisms. In this study, we focused on the diverse patterns of species richness on mountainsides. We conjectured that elevational range midpoints of species may be drawn towards a single midpoint attractor - a unimodal gradient of environmental favourability. The midpoint attractor interacts with geometric constraints imposed by sea level and the mountaintop to produce taxon-specific patterns of species richness. We developed a Bayesian simulation model to estimate the location and strength of the midpoint attractor from species occurrence data sampled along mountainsides. We also constructed midpoint predictor models to test whether environmental variables could directly account for the observed patterns of species range midpoints. We challenged these models with 16 elevational data sets, comprising 4500 species of insects, vertebrates and plants. The midpoint predictor models generally failed to predict the pattern of species midpoints. In contrast, the midpoint attractor model closely reproduced empirical spatial patterns of species richness and range midpoints. Gradients of environmental favourability, subject to geometric constraints, may parsimoniously account for elevational and other patterns of species richness.


Assuntos
Biodiversidade , Ecossistema , Modelos Biológicos , Animais , Teorema de Bayes , Insetos/fisiologia , Fenômenos Fisiológicos Vegetais , Vertebrados/fisiologia
6.
Angew Chem Int Ed Engl ; 54(45): 13420-4, 2015 Nov 02.
Artigo em Inglês | MEDLINE | ID: mdl-26367875

RESUMO

Based on the crystal structure of a natural protein substrate for microbial transglutaminase, an enzyme that catalyzes protein crosslinking, a recognition motif for site-specific conjugation was rationally designed. Conformationally locked by an intramolecular disulfide bond, this structural mimic of a native conjugation site ensured efficient conjugation of a reporter cargo to the therapeutic monoclonal antibody cetuximab without erosion of its binding properties.


Assuntos
Cetuximab/química , Transglutaminases/química , Animais , Células CHO , Linhagem Celular Tumoral , Cetuximab/metabolismo , Cricetulus , Dissulfetos/química , Dissulfetos/metabolismo , Humanos , Modelos Moleculares , Conformação Proteica , Transglutaminases/metabolismo
7.
Ecol Appl ; 24(4): 617-32, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-24988764

RESUMO

Biodiversity offsets are seen as a policy mechanism to balance development and conservation goals. Many offset schemes employ habitat restoration in one area to recreate biodiversity value that is destroyed elsewhere, assuming that recovery is timely and predictable. Recent research has challenged these assumptions on the grounds that restoration implies long time delays and a low certainty of success. To investigate these assertions, and to assess the strength of empirical support for offset policy, we used a meta-analytic approach to analyze data from 108 comparative studies of secondary growth (SG) and old-growth (OG) habitat (a total of 1228 SG sites and 716 OG reference sites). We extracted species checklists and calculated standardized response ratios for species richness, Fisher's alpha, Sorenson similarity, and Morisita-Horn similarity. We modeled diversity change with habitat age using generalized linear models and multi-model averaging, correcting for a number of potential explanatory variables. We tested whether (1) diversity of passively and actively restored habitat converges to OG values over time, (2) active restoration significantly accelerates this process, and (3) current offset policies are appropriate to the predicted uncertainties and time lags associated with restoration. The results indicate that in the best case, species richness converges to OG reference values within a century, species similarity (Sorenson) takes about twice as long, and assemblage composition (Morisita-Horn) up to an order of magnitude longer (hundreds to thousands of years). Active restoration significantly accelerates the process for all indices, but the inherently large time lags, uncertainty, and risk of restoration failure require offset ratios that far exceed what is currently applied in practice. Restoration offset policy therefore leads to a net loss of biodiversity, and represents an inappropriate use of the otherwise valuable tool of ecosystem restoration.


Assuntos
Biodiversidade , Conservação dos Recursos Naturais , Animais , Espécies em Perigo de Extinção , Monitoramento Ambiental , Modelos Biológicos
8.
Cancer Immunol Res ; 12(2): 144-148, 2024 02 02.
Artigo em Inglês | MEDLINE | ID: mdl-38231158

RESUMO

From September 20 to 23, 2023, the Seventh International Cancer Immunotherapy Conference was hosted jointly by the Cancer Research Institute, the European Network for Cancer Immunotherapy (ENCI), and the American Association for Cancer Research (AACR) in Milan, Italy. The four-day event covered the latest advances in cancer immunology and immunotherapy.


Assuntos
Neoplasias , Humanos , Neoplasias/terapia , Imunoterapia
9.
Cancer Cell ; 42(4): 568-582.e11, 2024 Apr 08.
Artigo em Inglês | MEDLINE | ID: mdl-38490213

RESUMO

Major histocompatibility complex (MHC) class I antigen presentation deficiency is a common cancer immune escape mechanism, but the mechanistic implications and potential strategies to address this challenge remain poorly understood. Studying ß2-microglobulin (B2M) deficient mouse tumor models, we find that MHC class I loss leads to a substantial immune desertification of the tumor microenvironment (TME) and broad resistance to immune-, chemo-, and radiotherapy. We show that treatment with long-lasting mRNA-encoded interleukin-2 (IL-2) restores an immune cell infiltrated, IFNγ-promoted, highly proinflammatory TME signature, and when combined with a tumor-targeting monoclonal antibody (mAB), can overcome therapeutic resistance. Unexpectedly, the effectiveness of this treatment is driven by IFNγ-releasing CD8+ T cells that recognize neoantigens cross-presented by TME-resident activated macrophages. These macrophages acquire augmented antigen presentation proficiency and other M1-phenotype-associated features under IL-2 treatment. Our findings highlight the importance of restoring neoantigen-specific immune responses in the treatment of cancers with MHC class I deficiencies.


Assuntos
Linfócitos T CD8-Positivos , Neoplasias , Animais , Camundongos , Antígenos de Histocompatibilidade Classe I/genética , Interleucina-2/genética , Interleucina-2/imunologia , Neoplasias/genética , RNA Mensageiro , Microambiente Tumoral
10.
Biol Lett ; 9(3): 20121146, 2013 Jun 23.
Artigo em Inglês | MEDLINE | ID: mdl-23536440

RESUMO

Many amphibian lineages show terrestrialization of their reproductive strategy and breeding is partially or completely independent of water. A number of causal factors have been proposed for the evolution of terrestrialized breeding. While predation has received repeated attention as a potential factor, the influence of other factors such as habitat has never been tested using appropriate data or methods. Using a dataset that comprises 180 amphibian species from various East African habitats, we tested whether species occurring in different habitats show different patterns of terrestrialization in their breeding strategy. We recovered a significant association between terrestrialized breeding strategies and forest habitats. In general, forest seems to act as a facilitator, providing a permissive environment for the evolution of terrestrialized breeding strategies. However, while terrestrial oviposition is strongly correlated with lowland and montane forest habitat, complete terrestrial development is significantly correlated with montane forest only, indicating different selective pressures acting at different steps towards complete terrestrial development.


Assuntos
Anfíbios/fisiologia , Árvores , África Oriental , Anfíbios/classificação , Animais , Ecossistema
11.
Am Nat ; 180(3): E64-74, 2012 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-22854086

RESUMO

Tropical beta diversity, and particularly that of herbivorous insects in rainforests, is often considered to be enormous, but this notion has recently been challenged. Because tropical beta diversity is highly relevant to our view on biodiversity, it is important to gain more insights and to resolve methodological problems that may lead to contradictions in different studies. We used data on two ecologically distinct moth families from Southeast Asia and analyzed separately the contribution of beta components to overall species richness at three spatial scales. Observed diversity partitions were compared under different types of null models. We found that alpha diversity was lower than expected on the basis of null models, whereas hierarchical beta components were larger than expected. Beta components played a significant role in shaping gamma diversity, and their contribution can be high (multiplicative beta >5). We found a reduction in beta components when comparing primary forests to agricultural sites (cf. "biotic homogenization"), but even in these habitats, beta components were still substantial. Our analyses show that beta components do play an important role in our data on tropical herbivorous insects and that these results are not attributable to lumping different habitats when sampling environmental gradients.


Assuntos
Biodiversidade , Mariposas , Animais , Bornéu , Malásia , Clima Tropical
12.
Hum Vaccin Immunother ; 18(6): 2124785, 2022 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-36222759

RESUMO

The 19th Annual Meeting of the Association for Cancer Immunotherapy (CIMT), Europe's cancer immunotherapy meeting, was the first in-person event organized by CIMT since the beginning of the COVID-19 pandemic. As a hybrid event from May 10-12, the meeting attracted 920 academic and clinical professionals from over 40 countries, who met to discuss the latest advances in cancer immunology and immunotherapy research. This report summarizes the highlights of CIMT2022.


Assuntos
COVID-19 , Neoplasias , Humanos , Pandemias , Neoplasias/terapia , COVID-19/terapia , Imunoterapia , Microambiente Tumoral
14.
Nat Ecol Evol ; 3(4): 539-551, 2019 04.
Artigo em Inglês | MEDLINE | ID: mdl-30858594

RESUMO

Species distributions and abundances are undergoing rapid changes worldwide. This highlights the significance of reliable, integrated information for guiding and assessing actions and policies aimed at managing and sustaining the many functions and benefits of species. Here we synthesize the types of data and approaches that are required to achieve such an integration and conceptualize 'essential biodiversity variables' (EBVs) for a unified global capture of species populations in space and time. The inherent heterogeneity and sparseness of raw biodiversity data are overcome by the use of models and remotely sensed covariates to inform predictions that are contiguous in space and time and global in extent. We define the species population EBVs as a space-time-species-gram (cube) that simultaneously addresses the distribution or abundance of multiple species, with its resolution adjusted to represent available evidence and acceptable levels of uncertainty. This essential information enables the monitoring of single or aggregate spatial or taxonomic units at scales relevant to research and decision-making. When combined with ancillary environmental or species data, this fundamental species population information directly underpins a range of biodiversity and ecosystem function indicators. The unified concept we present links disparate data to downstream uses and informs a vision for species population monitoring in which data collection is closely integrated with models and infrastructure to support effective biodiversity assessment.


Assuntos
Biodiversidade , Animais , Modelos Teóricos
15.
Oncoimmunology ; 8(3): 1553478, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30723585

RESUMO

Cancer-associated mutations, mostly single nucleotide variations, can act as neoepitopes and prime targets for effective anti-cancer T-cell immunity. T cells recognizing cancer mutations are critical for the clinical activity of immune checkpoint blockade (ICB) and they are potent vaccine antigens. High frequencies of mutation-specific T cells are rarely spontaneously induced. Hence, therapies that broaden the tumor specific T-cell response are of interest. Here, we analyzed neoepitope-specific CD8+ T-cell responses mounted either spontaneously or after immunotherapy regimens, which induce local tumor inflammation and cell death, in mice bearing tumors of the widely used colon carcinoma cell line CT26. A comprehensive immune reactivity screening of 2474 peptides covering 628 transcribed CT26 point mutations was conducted. All tested treatment regimens were found to induce a single significant CD8+ T-cell response against a non-synonymous D733A point mutation in the Smc3 gene. Surprisingly, even though Smc3 D733A turned out to be the immune-dominant neoepitope in CT26 tumor bearing mice, neither T cells specific for this neoepitope nor their T cell receptors (TCRs) were able to recognize or lyse tumor cells. Moreover, vaccination with the D733A neoepitope did not result in anti-tumoral activity despite induction of specific T cells. This is to our knowledge the first report that neoepitope specific CD8+ T cells primed by tumor-released antigen exposure in vivo can be functionally irrelevant.

16.
J Diabetes Sci Technol ; 13(2): 261-267, 2019 03.
Artigo em Inglês | MEDLINE | ID: mdl-30241444

RESUMO

In the last 10 years tremendous progress has been made in the development of artificial pancreas (AP) systems for people with type 1 diabetes (T1D). The pan-European consortium CLOSE (Automated Glu cose Contro l at H ome for People with Chronic Disea se) is aiming to develop integrated AP solutions (APplus) tailored to the needs of people with type 2 diabetes (T2D). APplus comprises a product and service package complementing the AP system by obligatory training as well as home visits and telemedical consultations on demand. Outcome predictors and performance indicators shall help to identify people who could benefit most from AP usage and facilitate the measurement of AP impact in diabetes care. In a first step CLOSE will establish a scalable APplus model case working at the interface between patients, homecare service providers, and payers in France. CLOSE will then scale up APplus by pursuing geographic distribution, targeting additional audiences, and enhancing AP functionalities and interconnectedness. By being part of the European Institute of Innovation and Technology (EIT) Health public-private partnership, CLOSE is committed to the EIT "knowledge triangle" pursuing the integrated advancement of technology, education, and business creation. Putting stakeholders, education, and impact into the center of APplus advancement is considered key for achieving wide AP use in T2D care.


Assuntos
Automonitorização da Glicemia/instrumentação , Glicemia/efeitos dos fármacos , Diabetes Mellitus Tipo 2/tratamento farmacológico , Sistemas de Infusão de Insulina , Pâncreas Artificial , Animais , Biomarcadores , Glicemia/metabolismo , Diabetes Mellitus Tipo 2/sangue , Diabetes Mellitus Tipo 2/diagnóstico , Desenho de Equipamento , Europa (Continente) , Humanos , Sistemas de Infusão de Insulina/efeitos adversos , Pâncreas Artificial/efeitos adversos , Projetos de Pesquisa , Participação dos Interessados , Resultado do Tratamento
17.
Hum Vaccin Immunother ; 14(12): 2864-2873, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30111232

RESUMO

The 16th Annual Meeting of the Association for Cancer Immunotherapy (CIMT), Europe's largest meeting series of its kind, took place in Mainz, Germany from 15-17 May, 2018. Cutting-edge advancements in cancer immunotherapy were discussed among more than 700 scientists under the motto "Pushing Frontiers in Cancer Immunotherapy". This meeting report is a summary of some of the CIMT 2018 highlights.


Assuntos
Imunoterapia , Neoplasias/terapia , Animais , Congressos como Assunto , Modelos Animais de Doenças , Quimioterapia Combinada , Humanos , Microambiente Tumoral , Vacinação , Ensaios Antitumorais Modelo de Xenoenxerto
18.
Methods Mol Biol ; 1685: 311-331, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29086318

RESUMO

Fluorescence-activated cell sorting (FACS) in combination with yeast surface display (YSD) has proven to be a valuable tool for the engineering of antibodies. It enables the fast and robust identification and isolation of candidates with prescribed characteristics from combinatorial libraries. A novel application for FACS and YSD that has recently evolved addresses the engineering of antibodies toward pH-switchable antigen binding, aiming at reduced binding at acidic pH, compared to neutral pH. Therefore, we give guidance for the incorporation of such pH switches into antibody variable domains using combinatorial histidine scanning libraries. The protocol describes a flow cytometric sorting technique for the enrichment of antigen-specific molecules. Moreover, we provide information on how to screen the obtained antibody pools from initial sorting to isolate and characterize pH-sensitive variants.


Assuntos
Separação Celular/métodos , Citometria de Fluxo/métodos , Fragmentos de Imunoglobulinas/isolamento & purificação , Saccharomyces cerevisiae/crescimento & desenvolvimento , Clonagem Molecular , Histidina/química , Humanos , Concentração de Íons de Hidrogênio , Fragmentos de Imunoglobulinas/metabolismo , Biblioteca de Peptídeos , Engenharia de Proteínas/métodos , Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/metabolismo
19.
Mol Biotechnol ; 60(10): 727-735, 2018 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-30076531

RESUMO

In this study, we present a multiparameter screening procedure for the identification of target-specific antibodies with prescribed properties. Based on B cell receptor gene repertoires from transgenic rats, yeast surface display libraries were generated, and high-affinity human antibodies were readily isolated. We demonstrate that specific desirable features, i.e., species' cross-reactivity and a broad epitope coverage can be integrated into the screening procedure using high-throughput fluorescence-activated cell sorting. We show that the applied screening stringencies translate directly into binding properties of isolated human antibody variants.


Assuntos
Anticorpos Monoclonais/genética , Anticorpos Monoclonais/isolamento & purificação , Separação Celular/métodos , Citometria de Fluxo/métodos , Saccharomyces cerevisiae/crescimento & desenvolvimento , Animais , Anticorpos Monoclonais/metabolismo , Afinidade de Anticorpos , Linhagem Celular , Técnicas de Visualização da Superfície Celular , Clonagem Molecular , Feminino , Humanos , Masculino , Biblioteca de Peptídeos , Ratos , Ratos Transgênicos , Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/metabolismo
20.
Ecology ; 88(8): 1877-88, 2007 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-17824415

RESUMO

We compiled 46 broadscale data sets of species richness for a wide range of terrestrial plant, invertebrate, and ectothermic vertebrate groups in all parts of the world to test the ability of metabolic theory to account for observed diversity gradients. The theory makes two related predictions: (1) In-transformed richness is linearly associated with a linear, inverse transformation of annual temperature, and (2) the slope of the relationship is near -0.65. Of the 46 data sets, 14 had no significant relationship; of the remaining 32, nine were linear, meeting prediction 1. Model I (ordinary least squares, OLS) and model II (reduced major axis, RMA) regressions then tested the linear slopes against prediction 2. In the 23 data sets having nonlinear relationships between richness and temperature, split-line regression divided the data into linear components, and regressions were done on each component to test prediction 2 for subsets of the data. Of the 46 data sets analyzed in their entirety using OLS regression, one was consistent with metabolic theory (meeting both predictions), and one was possibly consistent. Using RMA regression, no data sets were consistent. Of 67 analyses of prediction 2 using OLS regression on all linear data sets and subsets, two were consistent with the prediction, and four were possibly consistent. Using RMA regression, one was consistent (albeit weakly), and four were possibly consistent. We also found that the relationship between richness and temperature is both taxonomically and geographically conditional, and there is no evidence for a universal response of diversity to temperature. Meta-analyses confirmed significant heterogeneity in slopes among data sets, and the combined slopes across studies were significantly lower than the range of slopes predicted by metabolic theory based on both OLS and RMA regressions. We conclude that metabolic theory, as currently formulated, is a poor predictor of observed diversity gradients in most terrestrial systems.


Assuntos
Biodiversidade , Ecossistema , Metabolismo Energético/fisiologia , Modelos Biológicos , Temperatura , Animais , Geografia , Invertebrados/crescimento & desenvolvimento , Modelos Lineares , Desenvolvimento Vegetal , Valor Preditivo dos Testes , Análise de Regressão , Especificidade da Espécie
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