Neuroglia at the crossroads of homoeostasis, metabolism and signalling: evolution of the concept

Ever since Rudolf Virchow in 1858 publicly announced his apprehension of neuroglia being a true connective substance, this concept has been evolving to encompass a heterogeneous population of cells with various forms and functions. We briefly compare the 19th–20th century perspectives on neuroglia with the up-to-date view of these cells as an integral, and possibly integrating, component of brain metabolism and signalling in heath and disease. We conclude that the unifying property of otherwise diverse functions of various neuroglial cell sub-types is to maintain brain homoeostasis at different levels, from whole organ to molecular

An update on molecular cat allergens: Fel d 1 and what else? Chapter 1: Fel d 1, the major cat allergen

Background: Cats are the major source of indoor inhalant allergens after house dust mites. The global incidence of cat allergies is rising sharply, posing a major public health problem. Ten cat allergens have been identified. The major allergen responsible for symptoms is Fel d 1, a secretoglobin and not a lipocalin, making the cat a special case among mammals. Main body: Given its clinical predominance, it is essential to have a good knowledge of this allergenic fraction, including its basic structure, to understand the new exciting diagnostic and therapeutic applications currently in development. The recent arrival of the component-resolved diagnosis, which uses molecular allergens, represents a unique opportunity to improve our understanding of the disease. Recombinant Fel d 1 is now available for in vitro diagnosis by the anti-Fel d 1 specific IgE assay. The first part of the review will seek to describe the recent advances related to Fel d 1 in terms of positive diagnosis and assessment of disease severity. In daily practice, anti-Fel d 1 IgE tend to replace those directed against the overall extract but is this attitude justified? We will look at the most recent arguments to try to answer this question. In parallel, a second revolution is taking place thanks to molecular engineering, which has allowed the development of various forms of recombinant Fel d 1 and which seeks to modify the immunomodulatory properties of the molecule and thus the clinical history of the disease via various modalities of anti-Fel d 1-specific immunotherapy. We will endeavor to give a clear and practical overview of all these trends

Model-based 3-D Pose Estimation and Feature Tracking for Robot Assisted Surgery with Medical Imaging

Abstract — In this paper we address the problem of the pose estimation based on multiple geometrical features for monocular endoscopic vision with laparoscopes and for stereotaxy with CT scanners. Partial and full pose estimation (6 dofs) are considered with applications to minimally invasive surgery. At the University of Strasbourg, we have been developing a set of techniques for assisting surgeons in navigating and manipulating the three-dimensional space within the human body. In order to develop such systems, a variety of challenging visual tracking and registration problems with pre-operative and/or intra-operative images must be solved. This paper integrates several issues where computational vision can play a role. Depth recovery (from the tip of a surgical instrument w.r.t. living tissue), the Plücker coordinates (4 dofs) of a markerless cylindrical instrument, the 6 dofs of a needle-holder with an heterogeneous set of features and stereotaxy are the examples we describe. Projective invariants with perspective projection, quadrics of revolution and stereotactic markers are features which are useful to achieve the registration with uncalibrated or calibrated devices. Visual servoing-based tracking methods have been developed for image-guided robotic systems, for assisting surgeons in laparoscopic surgery and in interventional radiology. Real-time endoscopic vision and single-slice stereotactic registration has been proposed to retrieve the out-of-field of view instruments, to position a needle and to compensate small displacements like those due to patient breathing or any small disturbances which may occur during an image-guided surgical procedure. I

Aerobic and anaerobic biodegradability of polymer films and physico-chemical characterization

International audienceAerobic and anaerobic biodegradation of four different kinds of polymers, polylactic acid, polycaprolactone, a starch/polycaprolactone blend (Mater-bi®) and poly(butadiene adipate-co-terephthalate) (Eastar bio®) has been studied in the solid state under aerobic conditions and in the liquid phase under both aerobic and anaerobic conditions.Several standard test methods (ISO 14851, ISO 14853, ASTM G 21-90 and ASTM G 22-76 and NF X 41-514) were used to determine the biodegradability. To determine the efficiency of the biodegradation of polymers, quantitative (mass variations, oxygen uptake, pressure variations, biogas generation and composition, biodegradation percentages) and qualitative (variation of Tg and Tf, variation of molar mass by SEC, characterization by FTIR and NMR spectroscopy) analyses were made and materials were characterized before and after 28 days of degradation.After 28 days, the degradation of materials depends on the material and on the test conditions used. The degradation is better under aerobic conditions, in particular for Mater-bi and polycaprolactone. Nevertheless, we can notice that it is the amorphous part of the polymer which is more attacked by the micro-organisms but, after 28 days, they do not seem to cleave macromolecules inside the material: bacteria attack the surface of the polymer and seem to consume the macromolecules one after another (there is no significant variation in the molar mass and no difference between FTIR and NMR spectra before degradation and after 28 days of degradation)

Spontaneous skull base cerebrospinal fluid leak during pregnancy: a case report and review of the literature

BackgroundIdiopathic intracranial hypertension can lead to dural defects and spontaneous leakage of cerebrospinal fluid (CSF) from the skull base. Skull base CSF leaks are rarely reported in pregnancy but pose unique challenges for obstetricians and anesthesiologists.Case presentationA 31-year-old G4P1021 at 14 weeks developed debilitating headaches and CSF rhinorrhea. Brain imaging revealed a bony defect of the sphenoid sinus with a meningoencephalocele and a partially empty sella, consistent with CSF leakage from a skull base defect. The patient was neurologically stable without signs of meningitis; thus, management was focused on symptomatic alleviation. A planned cesarean section was performed at 38 weeks under spinal anesthesia. The patient had spontaneous marked improvement of her symptoms postpartum.ConclusionPregnancy may exacerbate skull base CSF leaks, requiring careful management with a multidisciplinary team. Neuraxial anesthesia can safely be performed in pregnant individuals with spontaneous skull base CSF leakage, but further studies are needed to determine the safest mode of delivery in these patients