Search results for "MIM"

Structural commonalities and deviations in the hierarchical organization of crossed-lamellar shells: A case study on the shell of the bivalve Glycyme…

2016

11 pages; International audience; The structural organization of the palliostracum—the dominant part of the shell which is formed by the mantle cells—of Glycymeris glycymeris (Linné 1758) is comprised of five hierarchical levels with pronounced structural commonalities and deviations from other crossed-lamellar shells. The hierarchical level known as second order lamellae, present within other crossed-lamellar shells, is absent highlighting a short-coming of the currently used nomenclature. On the mesoscale, secondary microtubules penetrate the palliostracum and serve as crack arrestors. Moreover, the growth lamellae follow bent trajectories possibly impacting crack propagation, crack defle…

In Situ, Light-Guided Axon Growth on Biomaterials via Photoactivatable Laminin Peptidomimetic IK(HANBP)VAV

2018

The ability to guide the growth of neurites is relevant for reconstructing neural networks and for nerve tissue regeneration. Here, a biofunctional hydrogel that allows light-based directional control of axon growth in situ is presented. The gel is covalently modified with a photoactivatable derivative of the short laminin peptidomimetic IKVAV. This adhesive peptide contains the photoremovable group 2-(4′-amino-4-nitro-[1,1′-biphenyl]-3-yl)propan-1-ol (HANBP) on the Lys rest that inhibits its activity. The modified peptide is highly soluble in water and can be simply conjugated to -COOH containing hydrogels via its terminal -NH 2 group. Light exposure allows presentation of the IKVAV adhesi…

Intravenous thrombolysis for suspected ischemic stroke with seizure at onset

2019

Objective Seizure at onset (SaO) has been considered a relative contraindication for intravenous thrombolysis (IVT) in patients with acute ischemic stroke, although this appraisal is not evidence based. Here, we investigated the prognostic significance of SaO in patients treated with IVT for suspected ischemic stroke. Methods In this multicenter, IVT-registry-based study we assessed the association between SaO and symptomatic intracranial hemorrhage (sICH, European Cooperative Acute Stroke Study II definition), 3-month mortality, and 3-month functional outcome on the modified Rankin Scale (mRS) using unadjusted and adjusted logistic regression, coarsened exact matching, and inverse probabil…

Human molecular chaperones share with SARS-CoV-2 antigenic epitopes potentially capable of eliciting autoimmunity against endothelial cells: possible…

2020

Severe acute respiratory syndrome corona virus 2 (SARS-CoV-2), the cause of COVID-19 disease, has the potential to elicit autoimmunity because mimicry of human molecular chaperones by viral proteins. We compared viral proteins with human molecular chaperones, many of which are heat shock proteins, to determine if they share amino acid-sequence segments with immunogenic-antigenic potential, which can elicit cross-reactive antibodies and effector immune cells with the capacity to damage-destroy human cells by a mechanism of autoimmunity. We identified the chaperones that can putatively participate in molecular mimicry phenomena after SARS-CoV-2 infection, focusing on those for which endotheli…

PPARδ Modulation by GW501516: An Unsuccessful Exercise Mimetic.

2017

Ubiquitous giants: a plethora of giant viruses found in Brazil and Antarctica

2018

Background Since the discovery of giant viruses infecting amoebae in 2003, many dogmas of virology have been revised and the search for these viruses has been intensified. Over the last few years, several new groups of these viruses have been discovered in various types of samples and environments.In this work, we describe the isolation of 68 giant viruses of amoeba obtained from environmental samples from Brazil and Antarctica. Methods Isolated viruses were identified by hemacolor staining, PCR assays and electron microscopy (scanning and/or transmission). Results A total of 64 viruses belonging to the Mimiviridae family were isolated (26 from lineage A, 13 from lineage B, 2 from lineage C…

Development of a New Antileishmanial Aziridine-2,3-Dicarboxylate-Based Inhibitor with High Selectivity for Parasite Cysteine Proteases

2015

ABSTRACT Leishmaniasis is one of the major neglected tropical diseases of the world. Druggable targets are the parasite cysteine proteases (CPs) of clan CA, family C1 (CAC1). In previous studies, we identified two peptidomimetic compounds, the aziridine-2,3-dicarboxylate compounds 13b and 13e, in a series of inhibitors of the cathepsin L (CL) subfamily of the papain clan CAC1. Both displayed antileishmanial activity in vitro while not showing cytotoxicity against host cells. In further investigations, the mode of action was characterized in Leishmania major . It was demonstrated that aziridines 13b and 13e mainly inhibited the parasitic cathepsin B (CB)-like CPC enzyme and, additionally, ma…

A new twist on sea silk : the peculiar protein ultrastructure of fan shell and pearl oyster byssus

2018

11 pages; International audience; Numerous mussel species produce byssal threads - tough proteinaceous fibers, which anchor mussels in aquatic habitats. Byssal threads from Mytilus species, which are comprised of modified collagen proteins - have become a veritable archetype for bio-inspired polymers due to their self-healing properties. However, threads from different species are comparatively much less understood. In particular, the byssus of Pinna nobilis comprises thousands of fine fibers utilized by humans for millennia to fashion lightweight golden fabrics known as sea silk. P. nobilis is very different from Mytilus from an ecological, morphological and evolutionary point of view and …

Development of novel 1,4-benzodiazepine-based Michael acceptors as antitrypanosomal agents

2016

Novel 1,4-benzodiazepines, endowed with a Michael acceptor moiety, were designed taking advantage of a computational prediction of their pharmacokinetic parameters. Among all the synthesized derivatives, we identified a new lead compound (i.e., 4a), bearing a vinyl ketone warhead and endowed with a promising antitrypanosomal activity against Trypanosoma brucei brucei (IC50 = 5.29 µM), coupled with a lack of cytotoxicity towards mammalian cells (TC50>100 µM).

Hierarchical architecture of sponge spicules: biocatalytic and structure-directing activity of silicatein proteins as model for bioinspired applicati…

2016

Since the first description of the silicateins, a group of enzymes that mediate the formation of the amorphous, hydrated biosilica of the skeleton of the siliceous sponges, much progress has been achieved in the understanding of this biomineralization process. These discoveries include, beside the proof of the enzymatic nature of the sponge biosilica formation, the dual property of the enzyme, to act both as a structure-forming and structure-guiding protein, and the demonstration that the initial product of silicatein is a soft, gel-like material that has to undergo a maturation process during which it achieves its favorable physical-chemical properties allowing the development of various t…