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1.
Nature ; 611(7936): 512-518, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-36261519

RESUMO

Long-term analyses of biodiversity data highlight a 'biodiversity conservation paradox': biological communities show substantial species turnover over the past century1,2, but changes in species richness are marginal1,3-5. Most studies, however, have focused only on the incidence of species, and have not considered changes in local abundance. Here we asked whether analysing changes in the cover of plant species could reveal previously unrecognized patterns of biodiversity change and provide insights into the underlying mechanisms. We compiled and analysed a dataset of 7,738 permanent and semi-permanent vegetation plots from Germany that were surveyed between 2 and 54 times from 1927 to 2020, in total comprising 1,794 species of vascular plants. We found that decrements in cover, averaged across all species and plots, occurred more often than increments; that the number of species that decreased in cover was higher than the number of species that increased; and that decrements were more equally distributed among losers than were gains among winners. Null model simulations confirmed that these trends do not emerge by chance, but are the consequence of species-specific negative effects of environmental changes. In the long run, these trends might result in substantial losses of species at both local and regional scales. Summarizing the changes by decade shows that the inequality in the mean change in species cover of losers and winners diverged as early as the 1960s. We conclude that changes in species cover in communities represent an important but understudied dimension of biodiversity change that should more routinely be considered in time-series analyses.


Assuntos
Biodiversidade , Plantas , Alemanha , Plantas/classificação , Especificidade da Espécie , Fatores de Tempo , Conjuntos de Dados como Assunto
2.
Eur J Haematol ; 90(4): 291-300, 2013 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-23294316

RESUMO

Chemotherapy and tyrosine kinase inhibitors provide high remission rates. However, prognosis of adult patients with Philadelphia chromosome-positive acute lymphoblastic leukaemia (Ph(+) ALL) still remains poor. Because most adults eventually relapse without allogeneic stem cell transplantation, which is not available for all patients, novel strategies are required for relapse prevention. As the integrity of the immune system is essential for the control of remaining leukaemia cells, we compared the efficacy of anthocyanins, imatinib and a DNA-based vaccine as non-immunosuppressant components with 6-mercaptopurine (6-MP) to control minimal residual disease in vitro and in vivo using different leukaemia cell lines and syngeneic mice. Proliferation of Ph(+) ALL was significantly better inhibited by anthocyanin-rich berry extract or imatinib compared with 6-MP. Although anthocyanins induced apoptosis in some leukaemia cell lines, the level of caspase-3, caspase-8 and caspase-9 was significantly lower compared with imatinib and 6-MP. When used as single components, anthocyanins and imatinib mesylate failed to eradicate pre-existing Ph(+) ALL in syngeneic mice, while 6-MP led to 10% and DNA vaccination to 56% survival. Intriguingly, only the combination of DNA vaccination with berry extract but not with the isolated anthocyanin, cyanidin-3-rutinoside or imatinib further increased leukaemia-free and overall survival, and 90% of lethally challenged mice survived. We suggest that induction and enhancement of a leukaemia-specific immunity by DNA vaccination and anthocyanin-rich berry extract can also decrease the relapse rate in patients with Ph(+) ALL. Furthermore, this approach may serve as strategy for maintenance therapy of other malignancies.


Assuntos
Antocianinas/uso terapêutico , Antineoplásicos Fitogênicos/uso terapêutico , Leucemia-Linfoma Linfoblástico de Células Precursoras/tratamento farmacológico , Adulto , Animais , Apoptose/efeitos dos fármacos , Benzamidas/uso terapêutico , Caspases/metabolismo , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Células HL-60 , Humanos , Mesilato de Imatinib , Células K562 , Quimioterapia de Manutenção , Camundongos , Camundongos Transgênicos , Piperazinas/uso terapêutico , Extratos Vegetais/uso terapêutico , Leucemia-Linfoma Linfoblástico de Células Precursoras/metabolismo , Leucemia-Linfoma Linfoblástico de Células Precursoras/patologia , Pirimidinas/uso terapêutico , Vacinas de DNA/uso terapêutico
3.
Sci Data ; 9(1): 631, 2022 10 19.
Artigo em Inglês | MEDLINE | ID: mdl-36261458

RESUMO

Vegetation-plot resurvey data are a main source of information on terrestrial biodiversity change, with records reaching back more than one century. Although more and more data from re-sampled plots have been published, there is not yet a comprehensive open-access dataset available for analysis. Here, we compiled and harmonised vegetation-plot resurvey data from Germany covering almost 100 years. We show the distribution of the plot data in space, time and across habitat types of the European Nature Information System (EUNIS). In addition, we include metadata on geographic location, plot size and vegetation structure. The data allow temporal biodiversity change to be assessed at the community scale, reaching back further into the past than most comparable data yet available. They also enable tracking changes in the incidence and distribution of individual species across Germany. In summary, the data come at a level of detail that holds promise for broadening our understanding of the mechanisms and drivers behind plant diversity change over the last century.


Assuntos
Biodiversidade , Ecossistema , Alemanha , Plantas
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