Allergic reactions following contrast material administration: nomenclature, classification, and mechanisms

In forensic pathology routine, fatal cases of contrast agent exposure can be occasionally encountered. In such situations, beyond the difficulties inherent in establishing the cause of death due to nonspecific or absent autopsy and histology findings as well as limited laboratory investigations, pathologists may face other problems in formulating exhaustive, complete reports, and conclusions that are scientifically accurate. Indeed, terminology concerning adverse drug reactions and allergy nomenclature is confusing. Some terms, still utilized in forensic and radiological reports, are outdated and should be avoided. Additionally, not all forensic pathologists master contrast material classification and pathogenesis of contrast agent reactions. We present a review of the literature covering allergic reactions to contrast material exposure in order to update used terminology, explain the pathophysiology, and list currently available laboratory investigations for diagnosis in the forensic setting

Microscopic versus Macroscopic Glass Transitions and Relevant Length Scales in Mixtures of Industrial Interest

We have combined X-ray diffraction, neutron diffraction with polarization analysis, small-angle neutron scattering (SANS), neutron elastic fixed window scans (EFWS), and differential scanning calorimetry (DSC) to investigate polymeric blends of industrial interest composed by isotopically labeled styrene–butadiene rubber (SBR) and polystyrene (PS) oligomers of size smaller than the Kuhn length. The EFWS are sensitive to the onset of liquid-like motions across the calorimetric glass transition, allowing the selective determination of the “microscopic” effective glass transitions of the components. These are compared with the “macroscopic” counterparts disentangled by the analysis of the DSC results in terms of a model based on the effects of thermally driven concentration fluctuations and self-concentration. At the microscopic level, the mixtures are dynamically heterogeneous for blends with intermediate concentrations or rich in PS, while the sample with highest content of the fast SBR component looks as dynamically homogeneous. Moreover, the combination of SANS and DSC has allowed determining the relevant length scale for the α-relaxation through its loss of equilibrium to be ≈30 Å. This is compared with the different characteristic length scales that can be identified in these complex mixtures from structural, thermodynamical, and dynamical points of view because of the combined approach followed. We also discuss the sources of the non-Gaussian effects observed for the atomic displacements and the applicability of a Lindemann-like criterion in these materials.We thank Marc Couty for fruitful discussions and Karine Vernay (Michelin Advanced Research) for dSBR synthesis. The authors acknowledge Grant PID2021-123438NB-I00 funded by MCIN/AEI/10.13039/501100011033 and by “ERDF A way of making Europe”, as well as financial support of Eusko Jaurlaritza (code: IT1566-22) and from the IKUR Strategy under the collaboration agreement between Ikerbasque Foundation and the Materials Physics Center on behalf of the Department of Education of the Basque Government. We acknowledge support of the publication fee by the CSIC Open Access Publication Support Initiative through its Unit of Information Resources for Research (URICI)

Imaging thrombosis with 99mTc-labeled RAM.1-antibody in vivo.

Platelets play a major role in thrombo-embolic diseases, notably by forming a thrombus that can ultimately occlude a vessel. This may provoke ischemic pathologies such as myocardial infarction, stroke or peripheral artery diseases, which represent the major causes of death worldwide. The aim of this study was to evaluate the specificity of radiolabeled Rat-Anti-Mouse antibody (RAM.1).We describe a method to detect platelets by using a RAM.1 coupled with the chelating agent hydrazinonicotinic acid (HYNIC) conjugated toWe demonstrated a quick and strong affinity of the radiolabeled RAM.1 for the platelet thrombus. Results clearly demonstrated the ability of this radioimmunoconjugate for detecting thrombi from 10 min post injection with an exceptional thrombi uptake. Using FeClThanks to the high sensitivity of SPECT, we provided evidence that [journal articleresearch support, non-u.s. gov't2018 062018 03 17importe

Brain simulation as a cloud service: The Virtual Brain on EBRAINS

The Virtual Brain (TVB) is now available as open-source services on the cloud research platform EBRAINS (ebrains.eu). It offers software for constructing, simulating and analysing brain network models including the TVB simulator; magnetic resonance imaging (MRI) processing pipelines to extract structural and functional brain networks; combined simulation of large-scale brain networks with small-scale spiking networks; automatic conversion of user-specified model equations into fast simulation code; simulation-ready brain models of patients and healthy volunteers; Bayesian parameter optimization in epilepsy patient models; data and software for mouse brain simulation; and extensive educational material. TVB cloud services facilitate reproducible online collaboration and discovery of data assets, models, and software embedded in scalable and secure workflows, a precondition for research on large cohort data sets, better generalizability, and clinical translation

nod Genes and Nod signals and the evolution of the rhizobium legume symbiosis.

The establishment of the nitrogen-fixing symbiosis between rhizobia and legumes requires an exchange of signals between the two partners. In response to flavonoids excreted by the host plant, rhizobia synthesize Nod factors (NFs) which elicit, at very low concentrations and in a specific manner, various symbiotic responses on the roots of the legume hosts. NFs from several rhizobial species have been characterized. They all are lipo-chitooligosaccharides, consisting of a backbone of generally four or five glucosamine residues N-acylated at the non-reducing end, and carrying various O-substituents. The N-acyl chain and the other substituents are important determinants of the rhizobial host specificity. A number of nodulation genes which specify the synthesis of NFs have been identified. All rhizobia, in spite of their diversity, possess conserved nodABC genes responsible for the synthesis of the N-acylated oligosaccharide core of NFs, which suggests that these genes are of a monophyletic origin. Other genes, the host specific nod genes, specify the substitutions of NFs. The central role of NFs and nod genes in the Rhizobium-legume symbiosis suggests that these factors could be used as molecular markers to study the evolution of this symbiosis. We have studied a number of NFs which are N-acylated by α,β-unsaturated fatty acids. We found that the ability to synthesize such NFs does not correlate with taxonomic position of the rhizobia. However, all rhizobia that produce NFs such nodulate plants belonging to related tribes of legumes, the Trifolieae, Vicieae, and Galegeae, all of them being members of the so-called galegoid group. This suggests that the ability to recognize the NFs with α,β-unsaturated fatty acids is limited to this group of legumes, and thus might have appeared only once in the course of legume evolution, in the galegoid phylum

Antiplatelet Drug Regimen in Patients With Stent Thrombosis ― Insights From the PESTO French Optical Coherence Tomography Registry ―

International audienceThrombosis) French multicenter prospective observational registry reported that a stent mechanical abnormality was present in 97% of subjects with ST explored by intracoro-nary optical coherence tomography (OCT) imaging. 5 Premature discontinuation and incomplete individual response to APT have previously been reported as major risk factors for ST. 6,7 However, the interactions between APT regimen and potential underlying stent abnormalities remain largely unknown, even though different mechanical substrates could favor a rheological environment that might promote thrombosis. For example, uncovered/poorly healed struts behave as foreign bodies that induce platelet A lthough its frequency has decreased over the recent past years, stent thrombosis (ST) remains a major complication of percutaneous coronary interventions (PCI) and still carries a high mortality. 1 ST is a mul-tifaceted process that can be triggered by different factors such as the patient's clinical characteristics, efficacy of anti-platelet therapy (APT) or underlying mechanical stent abnormalities. 2 However, coronary angiography has limited sensitivity to correctly identify these latter mechanisms and recent studies suggest that intracoronary imaging is a valuable option to achieve this purpose. 3,4 Therefore, the PESTO (Morphological Parameters Explaining Sten

Characteristics of stent thrombosis in bifurcation lesions analysed by optical coherence tomography

International audienceAIMS:This work aimed to investigate a cohort of patients presenting with stent thrombosis (ST) explored by optical coherence tomography (OCT) to identify the underlying mechanical abnormalities in case of bifurcation lesions.METHODS AND RESULTS:The PESTO study was a prospective national registry involving 29 French catheterisation facilities. Patients with acute coronary syndromes were prospectively screened for presence of definite ST and analysed by OCT after culprit lesion reopening. The cohort involved 120 subjects, including 21 patients (17.5% of the global PESTO group; median age: 62.6 yrs; 76% male) with bifurcation lesions. The clinical presentation was acute or subacute ST in 34%, late ST in 5% and very late ST in 62% of the patients. The main underlying mechanisms were strut malapposition in 33%, stent underexpansion in 19% and isolated strut uncoverage in 19% of the cases. The proximal main branch was involved in 71%, distal main branch in 52% and jailed side branch in 5% of the patients.CONCLUSIONS:In this cohort, bifurcation lesions represented a limited number of all ST cases. Different sections of the bifurcation could be involved. Although the underlying mechanisms were various, strut malapposition was the most frequently observed cause

Co/Ni(111) superlattices studied by microscopy, x-ray absorption, and ab initio calculations

International audienceWe explore the origins of perpendicular magnetic anisotropy in epitaxial and textured Co/Ni(111) superlattices using a combination of thin-film growth, structural characterization, x-ray magnetic circular dichroism (XMCD), and ab initio calculations. Transmission electron microscopy and x-ray diffraction experiments allow us to show that the " bulk " magnetoelastic contribution to the total magnetic energy is small compared to the interface anisotropy. The magnetic properties are studied by using XMCD at the Co and Ni L 2,3 edges. Hysteresis loops performed at the Co L 3 edge confirm the perpendicular magnetization for Co thicknesses up to four monolayers. The spin and orbital moments were deduced using the XMCD sum rules. The results are explained by considering two kinds of magnetic moments for Co, distinguishing the interfaces from the rest of the layers. Both effective spin and orbital moments of Co atoms are found to be enhanced at the Co-Ni interfaces, whereas the magnetic moment of Co surrounded by Co is similar to the bulk value. Ab initio calculations allow us to show a strong enhancement of the dipole operator contribution on Co atoms at the interface that is partly responsible for this high effective spin moment at the interface. Such a moment enhancement is not observed for Ni, with the dipole operator contribution being close to zero. Finally, we observed a very surprising proportionality between the effective spin and orbital moments, independent of the absorption edge or deposition technique used. We assign this peculiar behavior to the fact that the magnetic dipole operator involved in the sum rules is closely linked to the increase of the Co orbital moment at the interface. Based on XMCD results obtained on both molecular beam epitaxy and sputter-deposited samples, this link allows us to show the extreme sensitivity of the perpendicular anisotropy with the chemical ordering at the interface