Nanoanalytical analysis of bisphosphonate-driven alterations of microcalcifications using a 3D hydrogel system and in vivo mouse model

Vascular calcification predicts atherosclerotic plaque rupture and cardiovascular events. Retrospective studies of women taking bisphosphonates (BiPs), a proposed therapy for vascular calcification, showed that BiPs paradoxically increased morbidity in patients with prior acute cardiovascular events but decreased mortality in event-free patients. Calcifying extracellular vesicles (EVs), released by cells within atherosclerotic plaques, aggregate and nucleate calcification. We hypothesized that BiPs block EV aggregation and modify existing mineral growth, potentially altering microcalcification morphology and the risk of plaque rupture. Three-dimensional (3D) collagen hydrogels incubated with calcifying EVs were used to mimic fibrous cap calcification in vitro, while an ApoE-/- mouse was used as a model of atherosclerosis in vivo. EV aggregation and formation of stress-inducing microcalcifications was imaged via scanning electron microscopy (SEM) and atomic force microscopy (AFM). In both models, BiP (ibandronate) treatment resulted in time-dependent changes in microcalcification size and mineral morphology, dependent on whether BiP treatment was initiated before or after the expected onset of microcalcification formation. Following BiP treatment at any time, microcalcifications formed in vitro were predicted to have an associated threefold decrease in fibrous cap tensile stress compared to untreated controls, estimated using finite element analysis (FEA). These findings support our hypothesis that BiPs alter EV-driven calcification. The study also confirmed that our 3D hydrogel is a viable platform to study EV-mediated mineral nucleation and evaluate potential therapies for cardiovascular calcification

Resolving protein mixtures using microfluidic diffusional sizing combined with synchrotron radiation circular dichroism

Circular dichroism spectroscopy has become a powerful tool to characterise proteins and other biomolecules. For heterogeneous samples such as those present for interacting proteins, typically only average spectroscopic features can be resolved. Here we overcome this limitation by using free-flow microfluidic size separation in-line with synchrotron radiation circular dichroism to resolve the secondary structure of each component of a model protein mixture containing monomers and fibrils. To enable this objective, we have integrated far-UV compatible measurement chambers into PDMS-based microfluidic devices. Two architectures are proposed so as to accommodate for a wide range of concentrations. The approach, which can be used in combination with other bulk measurement techniques, paves the way to the study of complex mixtures such as the ones associated with protein misfolding and aggregation diseases including Alzheimer’s and Parkinson’s diseases

Image processing tools for the validation of CryoEM maps

The number of maps deposited in public databases (Electron Microscopy Data Bank, EMDB) determined by cryo-electron microscopy has quickly grown in recent years. With this rapid growth, it is critical to guarantee their quality. So far, map validation has primarily focused on the agreement between maps and models. From the image processing perspective, the validation has been mostly restricted to using two halfmapsand the measurement of their internal consistency. In this article, we suggest that map validation can be taken much further from the point of view of image processing if 2D classes, particles, angles, coordinates, defoci, and micrographs are also provided. We present a progressive validation scheme that qualifies a result validation status from 0 to 5 and offers three optional qualifiers (A, W, and O) that can be added. The simplest validation state is 0, while the most complete would be 5AWO. This scheme has been implemented in a website https://biocomp.cnb.csic.es/EMValidationService/ to which reconstructed maps and their ESI can be uploaded.We are thankful to Philip Baldwin, Dmitry Lyumkis, and Gabriel Lander for making their validation methods available (4.h and A.c). Javier Vargas and Jordi Burguet would like to thank the Spanish Ministry of Science and Innovation for financial support through the call 2019 Proyectos de I+D+i – RTI Tipo A (PID2019- 108850RA-I00) and Arrate Muñoz Barrutia, PID2019-109820RB-I00, MCIN/AEI/ 10.13039/501100011033/, cofinanced by European Regional Development Fund (ERDF), “A way of making Europe.”. The authors acknowledge the economic support from MICIN of the Instruct Image Processing Center (I2PC) as part of the Spanish participation in Instruct-ERIC, the European Strategic Infrastructure Project (ESFRI) in the area of Structural Biology, Grant PID2019-104757RB-I00 funded by MCIN/AEI/10.13039/501100011033/ and “ERDF A way of making Europe”, by the European Union and Grant PRE2020 - 093527 funded by MCIN/ AEI/ 10.13039/501100011033 and by “ESF Investing in your future”. We also acknowledge support from “Comunidad Autónoma de Madrid” through Grant: S2017/BMD-3817, Instituto de Salud Carlos III (project IMPaCT-Data, exp. IMP/ 00019), co-funded by the European Union, European Regional Development Fund (ERDF, “A way to make Europe”), and European Union (EU) and Horizon 2020 through grants: EOSC Life (INFRAEOSC-04-2018, Proposal: 824087), High- ResCells (ERC – 2018 – SyG, Proposal: 810057), IMpaCT (WIDESPREAD-03-2018 – Proposal: 857203), EOSC – Synergy (EINFRA-EOSC-5, Proposal: 857647), iNEXTDiscovery (Proposal: 871037), EnLaCES (H2020-MSCA-IF-2020, Proposal: 101024130)

Relationship between mitral leaflets angles, left ventricular geometry and mitral deformation indices in patients with ischemic mitral regurgitation: imaging by echocardiography and cardiac magnetic resonance

Chronic ischemic mitral regurgitation (IMR) is associated with a markedly worse prognosis after myocardial infarction (MI).The study aimed to evaluate the relationship between anterior and posterior mitral leaflet angle (MLA) values, left ventricle remodeling and severity of ischaemic mitral regurgitation (IMR). Methods: Forty-two patients (age 63.5 ± 9.7 years, 36 men) with chronic IMR (regurgitant volume, RV > 20 ml; >6 months after MI) underwent transthoracic echocardiography (TTE) and cardiovascular magnetic resonance (CMR) imaging. Anterior and posterior MLA, determined by echocardiography, were correlated with indices of LV remodeling, mitral apparatus deformation and IMR severity by CMR. The anterior and posterior MLA was 25.41 ± 4.28 and 38.37 ± 8.89° (mean ± SD). In 5 patients (11.9%) the posterior MLA was ≥45°. There was a significant correlation between anterior MLA and RV (r = 0.74, P = 0.01). For patients with RV > 30 ml this correlation was stronger (r = 0.97, P = 0.005) and, in addition, there was a correlation between the RV and posterior MLA (r = 0.90, P = 0.037), between tenting area and posterior MLA (r = 0.90, P = 0.04), and between tenting area and anterior MLA (r = 0.82, P = 0.08). With regard to LV remodeling parameters, there was weaker but significant correlation between posterior MLA and LV end-diastolic volume index (r = 0.35, P = 0.031), LV end-systolic volume index (r = 0.37, P = 0.021), stroke volume (r = 0.35, P = 0.03), sphericity index (r = 0.33, P = 0.041). Anterior MLA correlated with wall motion score index (r = 0.41, P = 0.019). Besides, there was a correlation between posterior MLA and left atrial volume (r = 0.41, P = 0.012). Measurement of anterior and posterior MLA may play an important role in evaluating patients with IMR

Continuous population-level monitoring of SARS-CoV-2 seroprevalence in a large European metropolitan region

Effective public health measures against SARS-CoV-2 require granular knowledge of population-level immune responses. We developed a Tripartite Automated Blood Immunoassay (TRABI) to assess the IgG response against three SARS-CoV-2 proteins. We used TRABI for continuous seromonitoring of hospital patients and blood donors (n = 72'250) in the canton of Zurich from December 2019 to December 2020 (pre-vaccine period). We found that antibodies waned with a half-life of 75 days, whereas the cumulative incidence rose from 2.3% in June 2020 to 12.2% in mid-December 2020. A follow-up health survey indicated that about 10% of patients infected with wildtype SARS-CoV-2 sustained some symptoms at least twelve months post COVID-19. Crucially, we found no evidence of a difference in long-term complications between those whose infection was symptomatic and those with asymptomatic acute infection. The cohort of asymptomatic SARS-CoV-2-infected subjects represents a resource for the study of chronic and possibly unexpected sequelae

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Information and communication technologies for special needed persons: A case study with a student with cerebral paralysi

The effect of variable dose and release kinetics on neointimal hyperplasia using a novel paclitaxel-eluting stent platform - The paclitaxel in-stent controlled elution study (PISCES)

ObjectivesThe aim of this study was to evaluate the effect of variable dose and release kinetics of paclitaxel on neointimal hyperplasia.BackgroundConventional paclitaxel-eluting stents use a durable polymer coating as a vehicle for drug delivery. The Conor stent (Conor Medsystems, Menlo Park, California) with intra-strut wells and erodable polymer is specifically designed for drug delivery with programmable pharmacokinetics.MethodsTwo hundred and forty-four patients with single vessel disease received either a bare metal Conor stent (n = 53) or one of six different release formulations that varied in dose (10 or 30 μg) and elution release kinetics (first order, zero order), direction (abluminal, luminal), and duration (5, 10, and 30 days). End points at six months (bare stent group) and at four months (eluting stent groups) were angiographic late loss and neointimal tissue volume by intravascular ultrasound and the rate of major adverse cardiac events (MACE).ResultsThe lowest in-stent late loss (0.38 mm, p <0.01, and 0.30 mm, p <0.01) and volume obstruction (8%, p <0.01, and 5%, p <0.01) were observed with the 10-μg and 30-μg doses in the 30-day release groups respectively, whereas the highest in-stent late loss (0.88 mm), volume obstruction (26%), and restenosis rate (11.6%) were observed in the bare stent group. The overall MACE rate of the eluting stent group was 8.6%: death 0.5%, myocardial infarction 2.7%, and target lesion revascularization (TLR) 5.3%. Sub-acute thrombosis was 0.5%. The TLR rates in the two 30-day release groups were 0% and 3.4%.ConclusionsThis novel eluting stent platform, using an erodable polymer with complete elution of low doses of paclitaxel, is safe. The inhibition of the in-stent neointimal hyperplasia was best in the long release groups