Long COVID and cardiovascular disease: a prospective cohort study

Background Pre-existing cardiovascular disease (CVD) or cardiovascular risk factors have been associated with an increased risk of complications following hospitalisation with COVID-19, but their impact on the rate of recovery following discharge is not known. Objectives To determine whether the rate of patient-perceived recovery following hospitalisation with COVID-19 was affected by the presence of CVD or cardiovascular risk factors. Methods In a multicentre prospective cohort study, patients were recruited following discharge from the hospital with COVID-19 undertaking two comprehensive assessments at 5 months and 12 months. Patients were stratified by the presence of either CVD or cardiovascular risk factors prior to hospitalisation with COVID-19 and compared with controls with neither. Full recovery was determined by the response to a patient-perceived evaluation of full recovery from COVID-19 in the context of physical, physiological and cognitive determinants of health. Results From a total population of 2545 patients (38.8% women), 472 (18.5%) and 1355 (53.2%) had CVD or cardiovascular risk factors, respectively. Compared with controls (n=718), patients with CVD and cardiovascular risk factors were older and more likely to have had severe COVID-19. Full recovery was significantly lower at 12 months in patients with CVD (adjusted OR (aOR) 0.62, 95% CI 0.43 to 0.89) and cardiovascular risk factors (aOR 0.66, 95% CI 0.50 to 0.86). Conclusion Patients with CVD or cardiovascular risk factors had a delayed recovery at 12 months following hospitalisation with COVID-19. Targeted interventions to reduce the impact of COVID-19 in patients with cardiovascular disease remain an unmet need

Large-scale phenotyping of patients with long COVID post-hospitalization reveals mechanistic subtypes of disease

One in ten severe acute respiratory syndrome coronavirus 2 infections result in prolonged symptoms termed long coronavirus disease (COVID), yet disease phenotypes and mechanisms are poorly understood1. Here we profiled 368 plasma proteins in 657 participants ≥3 months following hospitalization. Of these, 426 had at least one long COVID symptom and 233 had fully recovered. Elevated markers of myeloid inflammation and complement activation were associated with long COVID. IL-1R2, MATN2 and COLEC12 were associated with cardiorespiratory symptoms, fatigue and anxiety/depression; MATN2, CSF3 and C1QA were elevated in gastrointestinal symptoms and C1QA was elevated in cognitive impairment. Additional markers of alterations in nerve tissue repair (SPON-1 and NFASC) were elevated in those with cognitive impairment and SCG3, suggestive of brain–gut axis disturbance, was elevated in gastrointestinal symptoms. Severe acute respiratory syndrome coronavirus 2-specific immunoglobulin G (IgG) was persistently elevated in some individuals with long COVID, but virus was not detected in sputum. Analysis of inflammatory markers in nasal fluids showed no association with symptoms. Our study aimed to understand inflammatory processes that underlie long COVID and was not designed for biomarker discovery. Our findings suggest that specific inflammatory pathways related to tissue damage are implicated in subtypes of long COVID, which might be targeted in future therapeutic trials

PERFORMANCE AND APPLICATIONS OF A STEM-CATHODOLUMINESCENCE SYSTEM

Une revue des considérations de conception dont on a tenu compte dans le développement d'un système STEM-CL est donnée. Les résultats de la mise en oeuvre sont évalués par comparaison avec d'autres montages de détection de la luminescence de semiconducteurs. Finalement, quelques résultats typiques obtenus à l'aide du système sont utilisés comme exemples de son application.A review is given of the design considerations taken into account in developing a STEM CL System. The results of the implementation are evaluated in comparison with other arrangements for obtaining luminescence from semiconductors. Finally some typical results obtained with the System are used as examples of its application

The Study of Individual Free Standing GaAs/AlGaAs Quantum-dots by STEM-CL

Individual free-standing quantum-dots fabricated from a GaAs/AlGaAs quantum well structure by reactive-ion etching have been investigated. Severe damage occurred at the directly etched surface. Luminescence from a single quantum dot was detected. A loss of luminescence efficiency from the dots was observed. Energy-selected luminescence images of individual quantum-dots in an array were obtained.Des points quantiques libres, fabriqués par gravure ionique réactive à partir d'une structure de puits quantiques de GaAs/AlGaAs, sont étudiés. La surface directement attaquée, est sévèrement endommagée. On detecte la luminescence d'un point quantique. On observe une réduction de la luminescence provenant de ces points. Finalement, des images de luminescence filtrées en longueur d'onde, ont permis de visualiser des points quantiques individuels organisés en réseau

High-resolution TEM-CL from the cross-sectional specimens of GaAs/AlGaAs QWs

One of the advantages of the scanning transmission electron microscope cathodoluminescence (STEM-CL) technique is its higher spatial resolution in comparison with CL performed in a scanning electron microscope (SEM-CL). Our studies of cross-sectional specimens of a GaAs/AlGaAs quantum well structure have clearly demonstrated this. We believe that it is the first time that STEM-CL has been applied successfully to an electron transparent cross-sectional specimen. The aim of this study was to investigate the effect of different growth sequences on QW luminescence and to compare the quality of the successive QW sets. CL spectra were obtained from the cross-sectional samples by directing the electron beam onto each of QWs in turn. We observed marked differences in these spectra. Monochromatic CL images were also generated and they revealed clearly resolved emission from each of the separate sets of QWs in the structure. A spatial resolution of about 50nm was achieved transverse to the QWs in the monochromatic images of this particular structure