Density-based crystal plasticity : from the discrete to the continuum

Because of the enormous range of time and space scales involved in dislocation dynamics, plastic modeling at macroscale requires a continuous formulation. In this paper, we present a rigorous formulation of the transition between the discrete, where plastic flow is resolved at the scale of individual dislocations, and the continuum, where dislocations are represented by densities. First, we focus on the underlying coarse-graining procedure and show that the emerging correlation-induced stresses are scale-dependent. Each of these stresses can be expanded into the sum of two components. The first one depends on the local values of the dislocation densities and always opposes the sum of the applied stress and long-range mean field stress generated by the geometrically necessary dislocation (GND) density; this stress acts as a friction stress. The second component depends on the local gradients of the dislocation densities and is inherently associated to a translation of the elastic domain; therefore, it acts as a back-stress. We also show that these friction and back- stresses contain symmetry-breaking components that make the local stress experienced by dislocations to depend on the sign of their Burgers vector

Isoforms of endothelin-converting enzyme-1 (ECE-1) have opposing effects on prostate cancer cell invasion

Cross-talk between tumour and stromal cells can profoundly influence cancer cell invasion by increasing the availability of mitogenic peptides such as endothelin-1 (ET-1). Endothelin-1 is elevated in men with metastatic prostate cancer (PC), and can exert both an autocrine (epithelial) and a paracrine (stromal) influence on growth. Endothelin-1 is generated from its inactive precursor big-ET-1 by endothelin-converting enzyme 1 (ECE-1). We and others have demonstrated that ECE-1 expression is significantly elevated in tumours and surrounding stromal tissue. Our current data show siRNA-mediated knockdown of stromal ECE-1 reduces epithelial (PC-3) cell invasion in coculture. Interestingly, readdition of ET-1 only partially recovers this effect suggesting a novel role for ECE-1 independent of ET-1 activation. Parallel knockdown of ECE-1 in both stromal and epithelial compartments results in an additive decrease in cell invasion. We extrapolated this observation to the four recognised isoforms ECE-1a, ECE-1b, ECE-1c and ECE-1d. Only ECE-1a and ECE-1c were significant but with reciprocal effects on cell invasion. Transient ECE-1c overexpression increased PC-3 invasiveness through matrigel, whereas transient ECE-1a expression suppressed invasion. Furthermore, transient ECE-1a expression in stromal cells strongly counteracts the effect of transient ECE-1c expression in PC-3 cells. The ECE-1 isoforms may, therefore, be relevant targets for antiinvasive therapy in prostate and other cancers

Trials

BACKGROUND: Recent data suggest that 10-20% of injury patients will suffer for several months after the event from diverse symptoms, generally referred to as post-concussion-like symptoms (PCLS), which will lead to a decline in quality of life. A preliminary randomized control trial suggested that this condition may be induced by the stress experienced during the event or emergency room (ER) stay and can be prevented in up to 75% of patients with a single, early, short eye movement desensitization and reprocessing (EMDR) psychotherapeutic session delivered in the ER. The protocol of the SOFTER 3 study was designed to compare the impact on 3-month PCLS of early EMDR intervention and usual care in patients presenting at the ER. Secondary outcomes included 3-month post-traumatic stress disorder, 12-month PCLS, self-reported stress at the ER, self-assessed recovery expectation at discharge and 3 months, and self-reported chronic pain at discharge and 3 months. METHODS: This is a two-group, open-label, multicenter, comparative, randomized controlled trial with 3- and 12-month phone follow-up for reports of persisting symptoms (PCLS and post-traumatic stress disorder). Those eligible for inclusion were adults (>/=18 years old) presenting at the ER departments of the University Hospital of Bordeaux and University Hospital of Lyon, assessed as being at high risk of PCLS using a three-item scoring rule. The intervention groups were a (1) EMDR Recent Traumatic Episode Protocol intervention performed by a trained psychologist during ER stay or (2) usual care. The number of patients to be enrolled in each group was 223 to evidence a 15% decrease in PCLS prevalence in the EMDR group. DISCUSSION: In 2012, the year of the last national survey in France, 10.6 million people attended the ER, some of whom did so several times since 18 million visits were recorded in the same year. The SOFTER 3 study therefore addresses a major public health challenge. TRIAL REGISTRATION: Clinical Trials. NCT03400813 . Registered 17 January 2018 - retrospectively registered

Organization and chromosomal localization of the human ECEL1 (XCE) gene encoding a zinc metallopeptidase involved in the nervous control of respiration

ECEL1 (endothelin-converting enzyme-like 1; previously known as XCE) is a putative zinc metalloprotease that was identified recently on the basis of its strong identity with endothelin-converting enzyme. Although the physiological function of ECEL1 is unknown, inactivation of the corresponding gene in mice points to a critical role of this protein in the nervous control of respiration. In the present study we have characterized the human ECEL1 gene. It was located to region q36-q37 of chromosome 2 and shown to be composed of 18 exons spanning approx. 8 kb. The structure of the ECEL1 gene displays some striking similarities with those of genes of related metallopeptidases, supporting the hypothesis that they are all derived from a common ancestor. A short phylogenetic study describing the relationship between the various members of this gene family is also presented

Eur J Clin Microbiol Infect Dis

Campylobacter enteritis is the most frequent bacterial enteritis including in children. Its diagnosis suffers from the lack of sensitivity and delayed result of culture. Our aim was to test a new PCR-derived method for Campylobacter diagnosis in comparison to a composite reference. Patients presenting to the emergency ward of our hospital with enteric symptoms during the 2016 summer season were included. In addition to culture, an ELISA and an in-house real-time PCR were performed, as well as the new method (Orion GenRead Campylobacter) on all stool specimens. The composite reference used to consider a case positive for Campylobacter was either culture positive and in case of negative culture both the ELISA and real-time PCR positive. One hundred fifty patients were included, 64 being infants or children. There were 29 cases positive by the composite reference, with 19 of the 64 children (29.7%) and 10 of the 86 adults (11.6%). If performed alone, culture would have missed six cases. The Orion GenRead Campylobacter detected all the positives by the composite reference but also 12 cases negative by the composite reference (sensitivity 100%, specificity 90.1%). Given the characteristics of the new method, it can be used as a screening method for Campylobacter detection