Decontamination of genetically modified mice strains by embryo transfer for obtaining SPF colonies in a Brazilian animal facility

The introduction of new strains of mice in specific pathogen-free (SPF) animal facilities should be performed carefully to avoid breaking sanitary barriers. To meet this need, animals should be rederived to reduce infection risk and thus avoid research interference caused by loss of animal health status and welfare. The objective of this study was to implement mice embryo transfer in the laboratory mouse facility of the Department of Immunology at the Institute of Biomedical Sciences/University of São Paulo, Brazil. Embryo transfers were performed to rederive genetically modified mouse strains with undefined sanitary status, received from different research and educational institutions. Fertilized eggs at two-cell stage were obtained by natural means and transferred into the oviducts of SPF pseudo-pregnant female mice. All surgical procedures were performed under aseptic conditions. A total of 625 embryos were transferred into therecipients. 148 pups were born, of which 140 were reared. Viruses, bacteria and intestinal protozoa were eliminated using this technique. The improvement in the microbiological status of mice allowed their expansion in our SPF facility. With these results, we can stimulate the use of embryo transfer technique between rodent facilities in Brazil and thus encourage the distribution of better models to our scientific community.A introdução de novas linhagens de camundongos em biotérios livres de patógenos específicos (SPF) deve ser realizada com critérios para evitar a quebra das barreiras sanitárias. Dessa forma, os animais devem ser rederivados para reduzir os riscos de infecção e evitar as interferências provocadas pela perda do status sanitário e do bem-estar dos animais. O objetivo deste estudo foi implementar a transferência de embriões murinos no Biotério do Departamento de Imunologia do Instituto de Ciências Biomédicas da Universidade de São Paulo, Brasil. As transferências embrionárias foram realizadas para rederivar linhagens de camundongos geneticamente modificadas com status sanitário não conhecido, recebidas de diferentes instituições de pesquisa e de ensino. Os embriões em duas células foram obtidos pelos métodos naturais e transferidos para os ovidutos de fêmeas de camundongos SPF pseudoprenhas. Todos os procedimentos cirúrgicos foramrealizados sob condições assépticas. Um total de 625 embriões foram transferidos para as receptoras. Foram obtidos 148 filhotes nascidos vivos, destes 140 foram desmamados. Por meio desta técnica, foram eliminados vírus, bactérias e protozoários intestinais. A melhora no status microbiológico dos camundongos permitiu a expansão destes em nossa colônia SPF. Com esses resultados, podemos promover o uso da técnica de transferência de embriões entre os biotérios brasileiros e assim incentivar a distribuição de modelos mais adequados para a nossa comunidade científica

Papillomaviruses: a systematic review

Abstract In the last decades, a group of viruses has received great attention due to its relationship with cancer development and its wide distribution throughout the vertebrates: the papillomaviruses. In this article, we aim to review some of the most relevant reports concerning the use of bovines as an experimental model for studies related to papillomaviruses. Moreover, the obtained data contributes to the development of strategies against the clinical consequences of bovine papillomaviruses (BPV) that have led to drastic hazards to the herds. To overcome the problem, the vaccines that we have been developing involve recombinant DNA technology, aiming at prophylactic and therapeutic procedures. It is important to point out that these strategies can be used as models for innovative procedures against HPV, as this virus is the main causal agent of cervical cancer, the second most fatal cancer in women

Mutagenic Potential ofBos taurus Papillomavirus Type 1 E6 Recombinant Protein: First Description

Bovine papillomavirus (BPV) is considered a useful model to study HPV oncogenic process. BPV interacts with the host chromatin, resulting in DNA damage, which is attributed to E5, E6, and E7 viral oncoproteins activity. However, the oncogenic mechanisms of BPV E6 oncoprotein per se remain unknown. This study aimed to evaluate the mutagenic potential of Bos taurus papillomavirus type 1 (BPV-1) E6 recombinant oncoprotein by the cytokinesis-block micronucleus assay (CBMNA) and comet assay (CA). Peripheral blood samples of five calves were collected. Samples were subjected to molecular diagnosis, which did not reveal presence of BPV sequences. Samples were treated with 1 μg/mL of BPV-1 E6 oncoprotein and 50 μg/mL of cyclophosphamide (positive control). Negative controls were not submitted to any treatment. The samples were submitted to the CBMNA and CA. The results showed that BPV E6 oncoprotein induces clastogenesis per se, which is indicative of genomic instability. These results allowed better understanding the mechanism of cancer promotion associated with the BPV E6 oncoprotein and revealed that this oncoprotein can induce carcinogenesis per se. E6 recombinant oncoprotein has been suggested as a possible vaccine candidate. Results pointed out that BPV E6 recombinant oncoprotein modifications are required to use it as vaccine

Comentarios a una sentencia anunciada : el proceso Lula

El centenar de textos que conforman este libro -escritos por un movimiento de prestigiosos/as juristas y abogados- desgranan el procedimiento al que fue sometido Lula. En la opinión de las y los autores de los artículos las normas no fueron observadas, y su inobservancia llevó a que se dictaminase una decisión injusta. Frases del estilo "Voy a tomar una decisión revolucionaria, dejando de lado la ley, porque por la ley no se puede condenarlo de ninguna manera”, dichas en los juicios por las más altas autoridades judiciales militares y civiles, hoy son conocidas gracias a quienes se abocaron al trabajo de escuchar los audios de aquellas sesiones, nutriendo las reflexiones que argumentan sobre el imperativo de la hora: restablecer el estado de derecho y absolver al presidente Lula Da Silva

Comentários a uma sentença anunciada : o processo Lula

“Comentários a uma sentença: o Caso Lula” é talvez o mais importante documento jurídico publicado no Brasil em décadas. A presente coletânea de artigos nasceu de um movimento espontâneo e bastante significativo de juristas brasileiros e estrangeiros que examinaram cuidadosamente a sentença proferida no âmbito do processo que tramitou na 13ª Vara Federal de Curitiba, no caso que ficou conhecido na mídia como o do “tríplex do Guarujá”. <br>De la presentación de Geraldo Prad

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