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AimThe knowledge of biodiversity facets such as species composition, distribu-tion and ecological niche is fundamental for the construction of biogeographichypotheses and conservation strategies. However, the knowledge on these facetsis affected by major shortfalls, which are even more pronounced in the tropics.This study aims to evaluate the effect of sampling bias and variation in collec-tion effort on Linnean, Wallacean and Hutchinsonian shortfalls and diversitymeasures as species richness, endemism and beta-diversity.LocationBrazil.MethodsWe have built a database with over 1.5 million records of arthro-pods, vertebrates and angiosperms of Brazil, based on specimens deposited inscientific collections and on the taxonomic literature. We used null models totest the collection bias regarding the proximity to access routes. We also testedthe influence of sampling effort on diversity measures by regression models. Toinvestigate the Wallacean shortfall, we modelled the geographic distribution ofover 4000 species and compared their observed distribution with models. Toquantify the Hutchinsonian shortfall, we used environmental Euclidean distanceof the records to identify regions with poorly sampled environmental condi-tions. To estimate the Linnean shortfall, we measured the similarity of speciescomposition between regions close to and far from access routes.ResultsWe demonstrated that despite the differences in sampling effort, thestrong collection bias affects all taxonomic groups equally, generating a patternof spatially biased sampling effort. This collection pattern contributes greatly tothe biodiversity knowledge shortfalls, which directly affects the knowledge onthe distribution patterns of diversity.Main conclusionsThe knowledge on species richness, species composition andendemism in the Brazilian biodiversity is strongly biased spatially. Despite dif-ferences in sampling effort for each taxonomic group, roadside bias affectedthem equally. Species composition similarity decreased with the distance fromaccess routes, suggesting collection surveys at sites far from roads couldincrease the probability of sampling new geographic records or new species. ObjetivoO conhecimento das facetas da biodiversidade como composição, distribuição e nicho ecológico das espécies é fundamental para a construção de hipóteses biogeográficas e estratégias de conservação. No entanto, o conhecimento sobre essas facetas é afetado por grandes déficits, que são ainda mais pronunciados nos trópicos. Este estudo visa avaliar o efeito do viés de amostragem e variação no esforço de coleta sobre os déficits e medidas de diversidade de Linnean, Wallacean e Hutchinsonian como riqueza de espécies , endemismo e beta-diversidade.LocalizaçãoBrasil.MétodosConstruímos um banco de dados com mais de 1,5 milhão de registros de artrópodes, vertebrados e angiospermas do Brasil, com base em espécimes depositados em coleções científicas e na literatura taxonômica. Utilizamos modelos nulos para testar o viés de coleta quanto à proximidade das vias de acesso. Também testamos a influência do esforço amostral nas medidas de diversidade por meio de modelos de regressão. Para investigar o déficit Wallaceano, modelamos a distribuição geográfica de mais de 4.000 espécies e comparamos sua distribuição observada com modelos. Para quantificar o déficit hutchinsoniano, utilizamos a distância euclidiana ambiental dos registros para identificar regiões com condições ambientais pouco amostradas. Para estimar o déficit de Linne, medimos a similaridade da composição de espécies entre regiões próximas e distantes das vias de acesso. Resultados Demonstramos que apesar das diferenças no esforço amostral, o forte viés de coleta afeta igualmente todos os grupos taxonômicos, gerando um padrão de esforço amostral enviesado espacialmente. Esse padrão de coleta contribui muito para as deficiências de conhecimento da biodiversidade, o que afeta diretamente o conhecimento sobre os padrões de distribuição da diversidade.Principais conclusõesO conhecimento sobre riqueza de espécies, composição de espécies e endemismo na biodiversidade brasileira é fortemente enviesado espacialmente. Apesar das diferenças no esforço amostral para cada grupo taxonômico, o viés de beira de estrada os afetou igualmente. A similaridade da composição de espécies diminuiu com a distância das vias de acesso, sugerindo que levantamentos de coleta em locais distantes de estradas podem aumentar a probabilidade de amostragem de novos registros geográficos ou novas espécies.

Previous article in issueNext article in issue Fonseca and Venticinque (2018) (hereafter FV) present a critical assessment of a paper in which we attempt to estimate the biodiversity coverage of the Brazilian conservation units (Oliveira et al., 2017). We appreciate their contribution to this important debate. We have no doubts that conservation planning should be based on a variety of information sources, including not only the coverage of species? ranges but also the contribution of each area to the preservation of ecosystem services, landscape features and socioeconomic and cultural aspects. This systematic and integrative conservation planning is certainly a complex process, which requires the contribution of experts from different fields. However, we have shown, in this reply, that our paper (Oliveira et al., 2017) aims to quantify the knowledge and protection gaps of biodiversity in protected areas, not to propose priority areas or to test whether the current proposal of priority areas is efficient. Objectives and the conclusions of our paper. We hope this short response can clarify this debate. Fil: Oliveira, Ubirajara. Universidade Federal de Minas Gerais; Brasil Fil: Soares Filho, Britaldo Silveira. Universidade Federal de Minas Gerais; Brasil Fil: Paglia, Adriano Pereira. Universidade Federal de Minas Gerais; Brasil Fil: Brescovit, Antonio Domingos. Governo do Estado de Sao Paulo. Secretaria da Saude. Instituto Butantan; Brasil Fil: de Carvalho, Claudio J. B.. Universidade Federal do Paraná; Brasil Fil: Silva, Daniel Paiva. Instituto Federal Goiano; Brasil Fil: Teixeira de Rezende, Daniella. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Museo Argentino de Ciencias Naturales “Bernardino Rivadavia”; Argentina Fil: Leite, Felipe Sá Fortes. Universidade Federal de Viçosa; Brasil Fil: Batista, João Aguiar Nogueira. Universidade Federal de Minas Gerais; Brasil Fil: Barbosa, João Paulo Peixoto Pena. Governo do Estado de Sao Paulo. Secretaria da Saude. Instituto Butantan; Brasil Fil: Stehmann, João Renato. Universidade Federal de Minas Gerais; Brasil Fil: Ascher, John S.. National University Of Singapore; Singapur Fil: Vasconcelos, Marcelo Ferreira de. Instituto Prístino; Brasil Fil: De Marco, Paulo. Universidade Federal de Goiás; Brasil Fil: Löwenberg-Neto, Peter. Universidade Federal Da Integração Latino-americana; Brasil Fil: Ferro, Viviane Gianluppi. Universidade Federal de Goiás; Brasil Fil: Santos, Adalberto J.. Universidade Federal de Minas Gerais; Brasil

A promising antitumor xanthone derivative was optimized following a multidimensional approach that involved the synthesis of 17 analogues, the study of their lipophilicity and solubility, and the evaluation of their growth inhibitory activity on four human tumor cell lines. A new synthetic route for the hit xanthone derivative was also developed and applied for the synthesis of its analogues. Among the used cell lines, the HL-60 showed to be in general more sensitive to the compounds tested, with the most potent compound having a GI50 of 5.1 μM, lower than the hit compound. Lipophilicity was evaluated by the partition coefficient (K(p)) of a solute between buffer and two membrane models, namely liposomes and micelles. The compounds showed a logK(p) between 3 and 5 and the two membrane models showed a good correlation (r(2)=0.916) between each other. Studies concerning relationship between solubility and structure were developed for the hit compound and 5 of its analogues.

(1) Background: Our previous studies unveiled the hit thioxanthone TXA1 as an inhibitor of,P-glycoprotein (drug efflux pump) and of human tumor cells growth, namely of melanoma cells. SinceTXA1 is structurally similar to lucanthone (an autophagy inhibitor and apoptosis inducer) and to N10-substituted phenoxazines (isosteres of thioxanthones, and autophagy inducers), this study aimed at further assessing its cytotoxic mechanism and evaluating its potential as an autophagy modulator in A375-C5 melanoma cells; (2) Methods: Flow cytometry with propidium iodide (PI) for cell cycle profile analysis; Terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL) assay, flow cytometry with Annexin V/PI labeling and Western blot for apoptosis analysis were conducted. A pharmacophore approach was used for mapping TXA1 onto pharmacophores for autophagy induction. Autophagy analyses included transmission electron microscopy for visualization of autophagic structures, fluorescence microscopy for observation of monodansylcadaverine (MDC) staining, pattern of LC3 expression in the cells and acridine orange staining, and Western blot for autophagic proteins expression; (3) Results: TXA1 induced autophagy of melanoma cells at the GI50 concentration (3.6 μM) and apoptosis at twice that concentration. Following treatment with TXA1, autophagic structures were observed, together with the accumulation of autophagosomes and the formation of autophagolysosomes. An increase in LC3-II levels was also observed, which was reverted by 3-methyladenine (3-MA) (an early stage autophagy-inhibitor) but further increased by E-64d/pepstatin (late-stage autophagy inhibitors). Finally, 3-MA also reverted the effect of TXA1 in cellular viability; (4) Conclusion: TXA1 decreases the viability of melanoma cells by modulation of autophagy and may, therefore, serve as a lead compound for the development of autophagy modulators with antitumor activity. This work was financed by FEDER—Fundo Europeu de Desenvolvimento Regional funds through the COMPETE 2020—Operacional Programme for Competitiveness and Internationalisation (POCI), Portugal 2020, and by Portuguese funds through FCT—Fundação para a Ciência e a Tecnologia/ Ministério da Ciência, Tecnologia e Inovação in the framework of the project “Institute for Research and Innovation in Health Sciences (POCI-01-0145-FEDER-007274)”. The work was also funded by ERDF, COMPETE, and FCT under the projects PTDC/SAU-OSM/101437/2008, PTDC/MAR-BIO/4694/2014, and INNOVMAR—reference NORTE-01-0145-FEDER-000035, Research Line NOVELMAR. The authors also thank: FCT for D. Sousa and R.T. Lima grants (PTDC/SAU-FCT/100930/2008 and SFRH/BPD/68787/2010, respectively), QREN for D. Sousa grant (NORTE-07-0124-FEDER-000023).