Embryonic Diapause Is Conserved across Mammals

Embryonic diapause (ED) is a temporary arrest of embryo development and is characterized by delayed implantation in the uterus. ED occurs in blastocysts of less than 2% of mammalian species, including the mouse (Mus musculus). If ED were an evolutionarily conserved phenomenon, then it should be inducible in blastocysts of normally non-diapausing mammals, such as domestic species. To prove this hypothesis, we examined whether blastocysts from domestic sheep (Ovis aries) could enter into diapause following their transfer into mouse uteri in which diapause conditions were induced. Sheep blastocysts entered into diapause, as demonstrated by growth arrest, viability maintenance and their ED-specific pattern of gene expression. Seven days after transfer, diapausing ovine blastocysts were able to resume growth in vitro and, after transfer to surrogate ewe recipients, to develop into normal lambs. The finding that non-diapausing ovine embryos can enter into diapause implies that this phenomenon is phylogenetically conserved and not secondarily acquired by embryos of diapausing species. Our study questions the current model of independent evolution of ED in different mammalian orders

Accurate prediction of response to endocrine therapy in breast cancer patients: current and future biomarkers

WOS: 000390900700001PubMed ID: 27903276Approximately 70% of patients have breast cancers that are oestrogen receptor alpha positive (ER+) and are therefore candidates for endocrine treatment. Many of these patients relapse in the years during or following completion of adjuvant endocrine therapy. Thus, many ER+ cancers have primary resistance or develop resistance to endocrine therapy during treatment. Recent improvements in our understanding of how tumours evolve during treatment with endocrine agents have identified both changes in gene expression and mutational profiles, in the primary cancer as well as in circulating tumour cells. Analysing these changes has the potential to improve the prediction of which specific patients will respond to endocrine treatment. Serially profiled biopsies during treatment in the neoadjuvant setting offer promise for accurate and early prediction of response to both current and novel drugs and allow investigation of mechanisms of resistance. In addition, recent advances in monitoring tumour evolution through non-invasive (liquid) sampling of circulating tumour cells and cell-free tumour DNA may provide a method to detect resistant clones and allow implementation of personalized treatments for metastatic breast cancer patients. This review summarises current and future biomarkers and signatures for predicting response to endocrine treatment, and discusses the potential for using approved drugs and novel agents to improve outcomes. Increased prediction accuracy is likely to require sequential sampling, utilising preoperative or neoadjuvant treatment and/or liquid biopsies and an improved understanding of both the dynamics and heterogeneity of breast cancer.European CommissionEuropean Commission Joint Research Centre [658170]This work was funded by the European Commission H2020 Marie Sklodowska Curie Action Individual Fellowship (H2020-MSCA-IF, 658170) to CS and Breast Cancer Now to JMD and AHS

Anatomy and morphometric aspects of the trachea of Saimiri sciureus Linnaeus, 1758: knowledge for emergency procedures

The aim of this work is to study the morphological characteristics of the trachea of Saimiri sciureus through quantification and measurement of the cartilaginous rings, providing information to facilitate the election of more appropriate endotracheal tube, laryngeal mask or tracheostomy tube for anesthetic and emergency procedures, as it is a species of Neotropical primates most commonly used as biological models, and little is known about their morphology. Nine animals were investigated, being 4 adults and 5 young acquired from the Centro Nacional de Primatas (National Primate Center - CENP) - Ananindeua - PA, which died from natural causes and then fixed in aqueous buffered formalin 10%. Saimiri sciureus trachea comprises an average of 32.8 incomplete rings and an average length of 3.74 cm in young animals, while in adults it demonstrated an average of 30.25 rings and average length of 3.67 cm. The shape of the light and its proportion varied along the trachea. Endotracheal tube with a diameter the 2.0 - 2.5mm, laryngeal mask number 1.0 or tracheostomy tube neonatal Shiley number 3.0, can be placed in animals weighing 600g - 1.2 Kg. Given the great importance of the species studied, which is widely used as a biological model, the detailing on the morphology and morphometry of tracheal animal studies provides new approaches needed in respiratory emergency, as well as, facilitates the development of future anesthetic protocols.<br>Estudou-se as características morfológicas da traqueia do Saimiri sciureus através da quantificação e mensuração dos anéis cartilaginosos, a fim de fornecer informações que facilitem a eleição mais adequada de sonda endotraqueal, máscara laríngea ou cânula de trasqueostomia para procedimentos anestésicos e de emergência, visto que é uma das espécies de primatas neotropicais mais comumente utilizadas como modelos biológicos e pouco se sabe sobre sua morfologia. Foram utilizados nove animais, sendo quatro adultos e cinco jovens, oriundos do Centro Nacional de Primatas (CENP) - Ananindeua - PA, os quais vieram a óbito por causas naturais e, posteriormente, foram fixados em solução aquosa de formol tamponado a 10%. A traqueia do Saimiri sciureus é composta por uma média de 32, 8 anéis incompletos nos animais jovens e comprimento médio de 3, 74cm, já os adultos apresentam uma média de 30, 25 anéis e comprimento médio de 3, 67cm. A forma da luz e suas proporções variaram ao longo da traqueia. Sonda endotraqueal com diâmetro de 2, 0 - 2, 5mm, máscara laríngea número 1, 0 ou cânula de traqueostomia neonatal Shiley número 3, 0, podem ser colocados em animais pesando 600g - 1, 2 K. Dada a grande importância da espécie estudada, que é amplamente utilizada como modelo biológico, o detalhamento sobre o estudo da morfologia e morfometria traqueal animal, fornece novas abordagens necessárias em emergência respiratória, bem como facilita o desenvolvimento de futuros protocolos anestésicos