Cockayne Syndrome: The many challenges and approaches to understand a multifaceted disease

The striking and complex phenotype of Cockayne syndrome (CS) patients combines progeria-like features with developmental deficits. Since the establishment of the in vitro culture of skin fibroblasts derived from patients with CS in the 1970s, significant progress has been made in the understanding of the genetic alterations associated with the disease and their impact on molecular, cellular, and organismal functions. In this review, we provide a historic perspective on the research into CS by revisiting seminal papers in this field. We highlighted the great contributions of several researchers in the last decades, ranging from the cloning and characterization of CS genes to the molecular dissection of their roles in DNA repair, transcription, redox processes and metabolism control. We also provide a detailed description of all pathological mutations in genes ERCC6 and ERCC8 reported to date and their impact on CS-related proteins. Finally, we review the contributions (and limitations) of many genetic animal models to the study of CS and how cutting-edge technologies, such as cell reprogramming and state-of-the-art genome editing, are helping us to address unanswered questions

Avaliação de diferentes modelos de indução do diabete moderado em ratas Wistar e suas repercussões no organismo materno-fetal

Diabetes mellitus (DM) é uma doença crônica na qual a homeostase da glicose está comprometida, levando a um quadro hiperglicêmico que pode gerar outras complicações. A insulina, hormônio produzido pelo pâncreas, está diretamente relacionada à morbidade, por ser um dos principais mecanismos de regulação da glicemia. DM pode ser apresentar três classes: I) Tipo 1 (DM1), quando as células beta (β)-pancreáticas, produtoras de insulina, são destruídas de forma auto imune. II) Tipo 2 (DM 2), quando há deficiência na excreção ou ação da insulina e III) DM Gestacional, quando o quadro hiperglicêmico é diagnosticado pela primeira vez durante a gestação. Por motivos éticos e de controle de variáveis, modelos animais são utilizados para melhor compreensão dos mecanismos fisiopatológicos envolvidos no diabete. Para isso, existem diferentes modelos de indução em animais como o uso diferentes tipos de agentes β-citotóxicos, doses e vias para mimetizar a condição hiperglicêmica. Visando obter um modelo que apresente maior similaridade com o quadro diabético em humanos, este estudo avaliou e comparou diferentes modelos de indução do diabete de intensidade glicêmica moderada em ratas Wistar. Foram testados neste estudo quatro modelos em ratas Wistar com a administração de droga β-citotóxica, o streptozotocin (STZ) em diferentes momentos do período neonatal: 1) Administração de STZ no 1º dia de vida (D0) e acasalamento ao 90º dia de vida; 2) Administração de STZ no 4º dia de vida (D4) e acasalamento ao 90º dia de vida; 3) Administração de STZ no D0 e acasalamento ao 120º dia de vida e 4) Administração da STZ no D4 e acasalamento ao 120º dia de vida. Foram avaliados a eficiência da produção de animais diabéticos, a glicemia pós-prandial antes e durante a prenhez, performance no Teste de Tolerância à Glicose (TOTG), Teste de Tolerância a Insulina (TTI), desempenho reprodutivo materno, e peso...Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP

Brazilian Flora 2020: Leveraging the power of a collaborative scientific network

International audienceThe shortage of reliable primary taxonomic data limits the description of biological taxa and the understanding of biodiversity patterns and processes, complicating biogeographical, ecological, and evolutionary studies. This deficit creates a significant taxonomic impediment to biodiversity research and conservation planning. The taxonomic impediment and the biodiversity crisis are widely recognized, highlighting the urgent need for reliable taxonomic data. Over the past decade, numerous countries worldwide have devoted considerable effort to Target 1 of the Global Strategy for Plant Conservation (GSPC), which called for the preparation of a working list of all known plant species by 2010 and an online world Flora by 2020. Brazil is a megadiverse country, home to more of the world's known plant species than any other country. Despite that, Flora Brasiliensis, concluded in 1906, was the last comprehensive treatment of the Brazilian flora. The lack of accurate estimates of the number of species of algae, fungi, and plants occurring in Brazil contributes to the prevailing taxonomic impediment and delays progress towards the GSPC targets. Over the past 12 years, a legion of taxonomists motivated to meet Target 1 of the GSPC, worked together to gather and integrate knowledge on the algal, plant, and fungal diversity of Brazil. Overall, a team of about 980 taxonomists joined efforts in a highly collaborative project that used cybertaxonomy to prepare an updated Flora of Brazil, showing the power of scientific collaboration to reach ambitious goals. This paper presents an overview of the Brazilian Flora 2020 and provides taxonomic and spatial updates on the algae, fungi, and plants found in one of the world's most biodiverse countries. We further identify collection gaps and summarize future goals that extend beyond 2020. Our results show that Brazil is home to 46,975 native species of algae, fungi, and plants, of which 19,669 are endemic to the country. The data compiled to date suggests that the Atlantic Rainforest might be the most diverse Brazilian domain for all plant groups except gymnosperms, which are most diverse in the Amazon. However, scientific knowledge of Brazilian diversity is still unequally distributed, with the Atlantic Rainforest and the Cerrado being the most intensively sampled and studied biomes in the country. In times of “scientific reductionism”, with botanical and mycological sciences suffering pervasive depreciation in recent decades, the first online Flora of Brazil 2020 significantly enhanced the quality and quantity of taxonomic data available for algae, fungi, and plants from Brazil. This project also made all the information freely available online, providing a firm foundation for future research and for the management, conservation, and sustainable use of the Brazilian funga and flora