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Abstract The aim of this work was to develop an experimental protocol that takes into account the influence of experimental conditions on these perineal tissues, before determining their mechanical properties. Samples of each perineal tissue layer were obtained from the skin, the vagina, the external anal sphincter (EAS), the internal anal sphincter (IAS) and anal mucosa of freshly dead sows. They were tested in quasi-static uniaxial tension using the Mach-1 testing machine. Stress-strain curves of each perineal tissue layer before the first damage for each sow were obtained and modeled by hyperelastic laws described by three coefficients: C1, C2, and C3 (Yeoh model). The influence of sample preparation conditions such as tissue freezing, hygrometry and sample orientation were evaluated, and the conditions under which the tests were performed such as the displacement velocity during testing were also evaluated by analysing C1-coefficient. This study suggested that sample preparation conditions such as tissue freezing for 24 h, storage in cellophane paper for two hours and the strain rate did not statistically affect the C1-hyperelastic coefficient for each perineal layer (p > 0.05). Samples should not be stored in saline for 2 h (p 0.05). This experimental protocol could be used to study in vitro biomechanical properties of perineal tissues in order to better understand perineal tears during delivery.

Abstract We have previously introduced the first generation of C3P3, an artificial system that allows the autonomous in-vivo production of mRNA with m7GpppN-cap. While C3P3-G1 synthesized much larger amounts of capped mRNA in human cells than conventional nuclear expression systems, it produced a proportionately much smaller amount of the corresponding proteins, indicating a clear defect of mRNA translatability. A possible mechanism for this poor translatability could be the rudimentary polyadenylation of the mRNA produced by the C3P3-G1 system. We therefore sought to develop the C3P3-G2 system using an artificial enzyme to post-transcriptionally lengthen the poly(A) tail. This system is based on the mutant mouse poly(A) polymerase alpha fused at its N terminus with an N peptide from the λ virus, which binds to BoxBr sequences placed in the 3′UTR region of the mRNA of interest. The resulting system selectively brings mPAPαm7 to the target mRNA to elongate its poly(A)-tail to a length of few hundred adenosine. Such elongation of the poly(A) tail leads to an increase in protein expression levels of about 2.5–3 times in cultured human cells compared to the C3P3-G1 system. Finally, the coding sequence of the tethered mutant poly(A) polymerase can be efficiently fused to that of the C3P3-G1 enzyme via an F2A sequence, thus constituting the single-ORF C3P3-G2 enzyme. These technical developments constitute an important milestone in improving the performance of the C3P3 system, paving the way for its applications in bioproduction and non-viral human gene therapy.

Abstract Clinical value of pelvimetry in modern obstetrics practices has never been established and normal values are set since the middle of the twentieth century. The aim of this study was to describe current dimensions of pelvis in a female French Caucasian population. A retrospective, bi-centric observational study was conducted from August 2013 to August 2019 in two French departments of Obstetrics. We included all Caucasian women who had a computed tomography pelvimetry during pregnancy. The primary outcome was the values of the obstetric transverse diameter, obstetric conjugate diameter and bispinous diameter. Five hundred and fifty-one CT pelvimetries were analyzed. The median Obstetric Transverse Diameter (OTD) was 12.41 cm and the 3rd percentile was 11 cm. The median Obstetric Conjugate Diameter (OCD) was 12.2 cm and the 3rd percentile was 10.5 cm. The median Bispinous Diameter (BSD) in our data collection was 10.9 cm and the 3rd percentile was 9.3 cm. A significant correlation coefficient between women’s height and OTD, OCD and BSD was found. In our study, the OCD and the BSD have not evolved since the middle of the twentieth century. The obstetric transverse diameter was smaller than the standard currently used.

Abstract The aim of this work was to evaluate and compare the incidence of perineal tears and Obstetrical anal sphincter injuries (OASIS) after vaginal delivery following a in utero fetal death (IUFD) compared with those with a live-birth. We conducted a single-center, retrospective cohort study using a database of all women who underwent a spontaneous vaginal delivery in the level III maternity ward. Exclusion criteria were breech presentation, cesarean section birth, instrumental delivery, multiple pregnancy, delivery before 24 + 6 weeks of gestation (WG) and termination of pregnancy for medical reasons. Women from the database were divided into two groups: an "in utero fetal death" (IUFD) group and a control group. Women were included in the IUFD group if they had a spontaneous vaginal delivery following a fetal demise after 24 + 6 WG in cephalic presentation between January 2006 and June 2020. Women in the "control" group were selected from the same database and were included if they underwent a spontaneous vaginal delivery of a live fetus in cephalic presentation, after 24 + 6 WG, during the same period. Each woman in the "IUFD" group was matched to two women (ratio 1:2) in the control group for parity, maternal age, body mass index, gestation and birth weight. The primary outcome was the presence of a sutured or unsutured perineal tear. During the study period, 31,208 patients delivered at a level III maternity hospital. Among them, 215 and 430 women were included in the IUFD group and the control group respectively. The two groups were comparable for all demographic and clinical characteristics except for an epidural analgesia (92% versus 70% in the control group, p

Abstract Thiolation of uridine 34 in the anticodon loop of several tRNAs is conserved in the three domains of life and guarantees fidelity of protein translation. U34-tRNA thiolation is catalyzed by a complex of two proteins in the eukaryotic cytosol (named Ctu1/Ctu2 in humans), but by a single NcsA enzyme in archaea. We report here spectroscopic and biochemical experiments showing that NcsA from Methanococcus maripaludis (MmNcsA) is a dimer that binds a [4Fe-4S] cluster, which is required for catalysis. Moreover, the crystal structure of MmNcsA at 2.8 Å resolution shows that the [4Fe-4S] cluster is coordinated by three conserved cysteines only, in each monomer. Extra electron density on the fourth nonprotein-bonded iron most likely locates the binding site for a hydrogenosulfide ligand, in agreement with the [4Fe-4S] cluster being used to bind and activate the sulfur atom of the sulfur donor. Comparison of the crystal structure of MmNcsA with the AlphaFold model of the human Ctu1/Ctu2 complex shows a very close superposition of the catalytic site residues, including the cysteines that coordinate the [4Fe-4S] cluster in MmNcsA. We thus propose that the same mechanism for U34-tRNA thiolation, mediated by a [4Fe-4S]-dependent enzyme, operates in archaea and eukaryotes.

Abstract To compare pelvic organ prolapse (POP) recurrence and morbidity between first and second line sacrocolpopexies. We conducted a retrospective chart review of all laparoscopic or robotic sacrocolpopexies for POP-Q stage ≥ 2, with or without a history of previous prolapse repair, performed with a similar technique between January 2012 and June 2019 in 3 European Gynecologic Surgery Departments. Patients were separated into two groups: first line sacrocolpopexy (FLS) and second line sacrocolpopexy (SLS). Each patient from the SLS group was age-matched with a patient from the FLS group. The primary outcome measure was reoperation procedures for recurrent POP defined as a symptomatic POP-Q stage ≥ 2 POP in at least one vaginal compartment. Secondary outcomes included operative time, intraoperative organ trauma, intraoperative blood loss, postoperative POP recurrence (operated on or not), global reoperation and mesh-related complications. During this period, 332 patients were included. After age-matching, 170 patients were analyzed: 85 patients in the FLS and SLS groups, respectively. After a mean follow-up of 3 years, there was no statistically significant difference between the two groups in terms of recurrent POP (9.4% versus 10.6%, p = 0.7), recurrent POP reoperation (3.5% versus 5.9% p = 0.7), mesh-related reoperation (0% versus 2.4%, p = 0.5), global reoperation (3.5 versus 8.2%, p = 0.3), operative time (198 ± 67 min versus 193 ± 60 min, p = 0.5), intraoperative complications such as organ injury (4.7% versus 7.1%, p = 0.7) and blood loss > 500 mL (2.4% versus 0%, p = 0.5). Patients who underwent a first or a second line sacrocolpopexy seemed to have similar rates of prolapse recurrence and complications.

Abstract Glomerular hyperfiltration alone or associated with albuminuria is a well-known feature of sickle cell associated nephropathy. Though, glomerular hyperfiltration is currently considered to be related to a high renal plasma flow and chronic hemolysis, cardiac output influence on measured glomerular filtration rate (mGFR) have not been investigated so far. Thirty seven homozygous sickle cell patients (SCA) from the RAND study investigated before and under angiotensin converting enzyme inhibitor (ACEI) were included. Both mGFR and cardiac index (CI) were high (> 110 ml/min/1.73 m2 and > 3.5 l/m2 in 81% and 97% of cases) with low systemic vascular resistance (SVR) (

Abstract The ability of cells to respond to substrate-bound protein gradients is crucial for many physiological processes, such as immune response, neurogenesis and cancer cell migration. However, the difficulty to produce well-controlled protein gradients has long been a limitation to our understanding of collective cell migration in response to haptotaxis. Here we use a photopatterning technique to create circular, square and linear fibronectin (FN) gradients on two-dimensional (2D) culture substrates. We observed that epithelial cells spread preferentially on zones of higher FN density, creating rounded or elongated gaps within epithelial tissues over circular or linear FN gradients, respectively. Using time-lapse experiments, we demonstrated that the gap closure mechanism in a 2D haptotaxis model requires a significant increase of the leader cell area. In addition, we found that gap closures are slower on decreasing FN densities than on homogenous FN-coated substrate and that fresh closed gaps are characterized by a lower cell density. Interestingly, our results showed that cell proliferation increases in the closed gap region after maturation to restore the cell density, but that cell–cell adhesive junctions remain weaker in scarred epithelial zones. Taken together, our findings provide a better understanding of the wound healing process over protein gradients, which are reminiscent of haptotaxis.

Abstract Radiotherapy (RT) is one of the most frequently used methods for cancer treatment. Despite remarkable advancements in RT techniquesthe treatment of radioresistant tumours (i.e. high-grade gliomas) is not yet satisfactory. Finding novel approaches less damaging for normal tissues is of utmost importance. This would make it possible to increase the dose applied to tumours, resulting in an improvement in the cure rate. Along this line, proton minibeam radiation therapy (pMBRT) is a novel strategy that allows the spatial modulation of the dose, leading to minimal damage to brain structures compared to a high dose (25 Gy in one fraction) of standard proton therapy (PT). The aim of the present study was to evaluate whether pMBRT also preserves important cerebral functions. Comprehensive longitudinal behavioural studies were performed in irradiated (peak dose of 57 Gy in one fraction) and control rats to evaluate the impact of pMBRT on motor function (motor coordination, muscular tonus, and locomotor activity), emotional function (anxiety, fear, motivation, and impulsivity), and cognitive function (learning, memory, temporal processing, and decision making). The evaluations, which were conducted over a period of 10 months, showed no significant motor or emotional dysfunction in pMBRT-irradiated rats compared with control animals. Concerning cognitive functions, similar performance was observed between the groups, although some slight learning delays might be present in some of the tests in the long term after irradiation. This study shows the minimal impact of pMBRT on the normal brain at the functional level.