PULCHER – Pulsed Chemical Rocket with Green High Performance Propellants: Project Overview

PulCheR is a research project co-funded by the European Union Seventh Framework Programme (FP7/2007-2013) under grant agreement n°313271, officially started as of January 1st, 2013. The project is mainly aimed at demonstrating the feasibility of a pulsed propulsion system in which the propellants are fed in the combustion chamber at low pressure and the thrust is generated by means of high frequency pulses, reproducing the defence mechanism of a notable insect: the bombardier beetle. The suitable design of the feeding lines, comprehensive of the injectors, allows the low pressure injection of the correct amount of propellants into the combustion chamber: the decomposition or combustion reaction increase the chamber pressure that rises to values much higher than the one at which the propellants are stored, exploiting the advantages of quasi constant volume combustion. The combustion products are accelerated through a convergent-divergent nozzle generating the thrust pulse and once the pressure inside the combustion chamber decreases under the injection pressure, the cycle can be repeated. The feasibility of this new propulsion concept will be investigated at breadboard level in both mono and bipropellant configurations through the design, realization and testing of a platform of the overall propulsion system including all its main components. In addition, the concept will be investigated using green propellants with potential similar performance to the current state-of-the-art for monopropellant and bipropellant thrusters. The present paper aims at presenting the main objectives and the current status of the PulCheR project

Uncoupled Embryonic and Extra-Embryonic Tissues Compromise Blastocyst Development after Somatic Cell Nuclear Transfer

Somatic cell nuclear transfer (SCNT) is the most efficient cell reprogramming technique available, especially when working with bovine species. Although SCNT blastocysts performed equally well or better than controls in the weeks following embryo transfer at Day 7, elongation and gastrulation defects were observed prior to implantation. To understand the developmental implications of embryonic/extra-embryonic interactions, the morphological and molecular features of elongating and gastrulating tissues were analysed. At Day 18, 30 SCNT conceptuses were compared to 20 controls (AI and IVP: 10 conceptuses each); one-half of the SCNT conceptuses appeared normal while the other half showed signs of atypical elongation and gastrulation. SCNT was also associated with a high incidence of discordance in embryonic and extra-embryonic patterns, as evidenced by morphological and molecular “uncoupling”. Elongation appeared to be secondarily affected; only 3 of 30 conceptuses had abnormally elongated shapes and there were very few differences in gene expression when they were compared to the controls. However, some of these differences could be linked to defects in microvilli formation or extracellular matrix composition and could thus impact extra-embryonic functions. In contrast to elongation, gastrulation stages included embryonic defects that likely affected the hypoblast, the epiblast, or the early stages of their differentiation. When taking into account SCNT conceptus somatic origin, i.e. the reprogramming efficiency of each bovine ear fibroblast (Low: 0029, Med: 7711, High: 5538), we found that embryonic abnormalities or severe embryonic/extra-embryonic uncoupling were more tightly correlated to embryo loss at implantation than were elongation defects. Alternatively, extra-embryonic differences between SCNT and control conceptuses at Day 18 were related to molecular plasticity (high efficiency/high plasticity) and subsequent pregnancy loss. Finally, because it alters re-differentiation processes in vivo, SCNT reprogramming highlights temporally and spatially restricted interactions among cells and tissues in a unique way

Vitrification alters rabbit foetal placenta at transcriptomic and proteomic level

Although numerous studies have demonstrated that cryopreservation alters gene expression of early embryos and questions the neutrality of the technique in adulthood, less is known about those embryos that implanted successfully and continued in gestation. To raise the question of the neutrality of this technique, we examine the effects of vitrification through the rabbit gestation before and after the implantation. We monitored the distribution of losses of 569 vitrified morulae, observing that embryos which reach the last pre-implantatory stage are able to implant. However, we found that not all implanted embryos had the ability to continue with their gestation. The results reveal that vitrification decreased foetus and maternal placenta weights at mid-gestation, but led to a higher offspring birth weight. A novel finding is that while no differences in gene expression were detected in pre-implantatory embryos at day 6, vitrification affects a gene and protein expression in the placenta at day 14. Our results reveal for first time strong evidence of modifications in implanted embryos subjected to vitrification, suggesting that the crucial step that vitrified embryos must overcome is the placenta formation. Based on these findings, our work leaves the question open as to whether the effects we observed that cause vitrification during foetal development could give rise to some type of physiological or metabolic alteration in adulthood.This work was supported by the Generalitat Valenciana research program (Prometeo 2009/125) and the Spanish Research Projects (CICYT AGL2011-29831-C03-01). M D Saenz-de-Juano was supported by a research grant from Generalitat Valenciana (Programa VALI+d, ACIF/2011/254).Saenz De Juano Ribes, MDLD.; Marco Jiménez, F.; Schmaltz-Panneau, B.; Jiménez Trigos, ME.; Viudes De Castro, MP.; Peñaranda, D.; Jouneau, L.... (2014). Vitrification alters rabbit foetal placenta at transcriptomic and proteomic level. Reproduction. 147(6):789-801. doi:10.1530/REP-14-0019S789801147

Feasibility of a prehabilitation programme dedicated to older patients with cancer before complex medical–surgical procedures: the PROADAPT pilot study protocol

Background Ageing is associated with an increased prevalence of comorbidities and sarcopenia as well as a decline of functional reserve of multiple organ systems, which may lead, in the context of the disease-related and/or treatment-related stress, to functional deconditioning. The multicomponent ‘Prehabilitation & Rehabilitation in Oncogeriatrics: Adaptation to Deconditioning risk and Accompaniment of Patients’ Trajectories (PROADAPT)’ intervention was developed multiprofessionally to implement prehabilitation in older patients with cancer.Methods The PROADAPT pilot study is an interventional, non-comparative, prospective, multicentre study. It will include 122 patients oriented to complex medical–surgical curative procedures (major surgery or radiation therapy with or without chemotherapy). After informed consent, patients will undergo a comprehensive geriatric assessment and will be offered a prehabilitation kit that includes an advice booklet with personalised objectives and respiratory rehabilitation devices. Patients will then be called weekly and monitored for physical and respiratory rehabilitation, preoperative renutrition, motivational counselling and iatrogenic prevention. Six outpatient visits will be planned: at inclusion, a few days before the procedure and at 1, 3, 6 and 12 months after the end of the procedure. The main outcome of the study is the feasibility of the intervention, defined as the ability to perform at least one of the components of the programme. Clinical data collected will include patient-specific and cancer-specific characteristics.Ethics and dissemination The study protocol was approved by the Ile de France 8 ethics committee on 5 June 2018. The results of the primary and secondary objectives will be published in peer-reviewed journals.Trial registration number NCT03659123. Pre-results of the trial