A cohort study reveals different dynamics of SARS-CoV-2-specific antibody formation after Comirnaty and Vaxzevria vaccination.

The Coronavirus (COVID-19) Disease Pandemic, caused by the Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2), has affected millions of people worldwide, prompting a collective effort from the global scientific community to develop a vaccine against it. This study purports to investigate the influence of factors such as sex, age, type of vaccination (Comirnaty, BNT162b2, Pfizer Inc. or Vaxzevria, ChAdOx1-S, Oxford/AstraZeneca), and time since vaccine administration on the process of antibody production. Both of them are based on the introduction of SARS-CoV-2 spike protein (S protein) to the body using different mechanisms (mRNA and recombinant adenovirus, respectively). S protein is responsible for host cell attachment and penetration via its receptor-binding domain (RBD domain). The level of anti-RBD IgG antibodies was tested with an ELISA-based immunodiagnostic assay in serum samples from a total of 1395 patients at 3 time points: before vaccination, after the first dose, and after the second dose. Our novel statistical model, the Generalized Additive Model, revealed variability in antibody production dynamics for both vaccines. Interestingly, no discernible variation in antibody levels between men and women was found. A nonlinear relationship between age and antibody production was observed, characterized by decreased antibody levels for people up to 30 and over 60 years of age, with a lack of correlation in the middle age range. Collectively, our findings further the understanding of the mechanism driving vaccine-induced immunity. Additionally, we propose the Generalized Additive Model as a standardized way of presenting data in similar research.

Hyaluronic acid and multiwalled carbon nanotubes as bioink additives for cartilage tissue engineering.

Articular cartilage and meniscus injuries are prevalent disorders with insufficient regeneration responses offered by available treatment methods. In this regard, 3D bioprinting has emerged as one of the most promising new technologies, offering novel treatment options. Additionally, the latest achievements from the fields of biomaterials and tissue engineering research identified constituents facilitating the creation of biocompatible scaffolds. In this study, we looked closer at hyaluronic acid and multi-walled carbon nanotubes as bioink additives. Firstly, we assessed the minimal concentrations that stimulate cell viability, and decrease reactive oxygen species and apoptosis levels in 2D cell cultures of normal human knee articular chondrocytes (NHAC) and human adipose-derived mesenchymal stem cells (hMSC-AT). In this regard, 0.25 mg/ml of hyaluronic acid and 0.0625 mg/ml of carbon nanotubes were selected as the most optimal concentrations. In addition, we investigated the protective influence of 2-phospho-L-ascorbic acid in samples with carbon nanotubes. Tests conducted on 3D bioprinted constructs revealed that only a combination of components positively impacted cell viability throughout the whole experiment. Gene expression analysis of COL1A1, COL6A1, HIF1A, COMP, RUNX2, and POU5F1 showed significant changes in the expression of all analyzed genes with a progressive overall loss of transcriptional activity in most of them.

Analysis of the Planar Point Identification Accuracy in CMM Measurements.

The paper presents the results of the investigations on the direction-dependent accuracy of the point identification during contact probe measurements with a coordinate measuring machine (CMM). Considering the contact point identified by an orthogonal to the surface probe movement, the transformation of coordinates was made in order to calculate the displacement of the measured point. As a result, the positioning accuracy was estimated in three axes. The experiments demonstrated a strong dependence of the displacement on the declination angle. Moreover, it was found that the directional surface texture which provided different roughness in perpendicular directions, had an impact on the positioning accuracy.

Budget impact analysis of a machine learning algorithm to predict high risk of atrial fibrillation among primary care patients.

AIMS: We investigated whether the use of an atrial fibrillation (AF) risk prediction algorithm could improve AF detection compared with opportunistic screening in primary care and assessed the associated budget impact. METHODS AND RESULTS: Eligible patients were registered with a general practice in UK, aged 65 years or older in 2018/19, and had complete data for weight, height, body mass index, and systolic and diastolic blood pressure recorded within 1 year. Three screening scenarios were assessed: (i) opportunistic screening and diagnosis (standard care); (ii) standard care replaced by the use of the algorithm; and (iii) combined use of standard care and the algorithm. The analysis considered a 3-year time horizon, and the budget impact for the National Health Service (NHS) costs alone or with personal social services (PSS) costs. Scenario 1 would identify 79 410 new AF cases (detection gap reduced by 22%). Scenario 2 would identify 70 916 (gap reduced by 19%) and Scenario 3 would identify 99 267 new cases (gap reduction 27%). These rates translate into 2639 strokes being prevented in Scenario 1, 2357 in Scenario 2, and 3299 in Scenario 3. The 3-year NHS budget impact of Scenario 1 would be £45.3 million, £3.6 million (difference ‒92.0%) with Scenario 2, and £46.3 million (difference 2.2%) in Scenario 3, but for NHS plus PSS would be ‒£48.8 million, ‒£80.4 million (64.8%), and ‒£71.3 million (46.1%), respectively. CONCLUSION: Implementation of an AF risk prediction algorithm alongside standard opportunistic screening could close the AF detection gap and prevent strokes while substantially reducing NHS and PSS combined care costs.

Comparison of routine computed tomography and plain X-ray imaging for malleolar fractures-How much do we miss?

PURPOSE: Most patients with ankle arthrosis have a history of ankle fracture. Evaluation of malleolar fractures solely on X-ray may be insufficient to identify many pathologies that potentially contribute to ankle arthrosis, with a consequent poor prognosis. We investigated the pathologies that may be overlooked in malleolar fractures evaluated solely on plain X-ray. METHODS: During 2012-2019, 65,479 patients attended our Emergency Department, of which 6508 complained of an ankle joint problem. X-rays indicated a fracture in 454 of these patients. Patients with isolated, simple fracture of the lateral or medial malleolus, or talus, or a history of surgery to this area were excluded; finally, 67 patients were enrolled (31 males, 36 females; mean age: 51,2 years (range: 9-83 years). Patients underwent X-ray imaging of both ankles in anterio-posterior, lateral, and Mortise views, as well as CT scans. Three independent observers with varied experience in diagnostic imaging (orthopaedic resident, experienced orthopaedic surgeon, and musculoskeletal radiologist) evaluated X-ray images blinded to CT scans. Their diagnoses were subsequently compared with CT findings. RESULTS: Modeling results indicated that about 40% [95% CI: 32%, 50%] of pathologies may be overlooked based on X-ray evaluation, regardless of evaluator experience. The most frequently overlooked injuries were: Tillaux fracture, Pillon fracture, loose bodies and syndesmosis injury. All of that missed pathologies required dedicated treatment and could be easily missed with standard surgical approach. CONCLUSION: Evaluation of malleolar fractures by X-ray only inevitably results in overlooking of many pathologies, despite the clinician's experience. Routine CT scan can help to improve the accuracy of diagnosis, and thereby reduce the risk of ankle osteoarthrosis.

Photodegradation of Biohazardous Dye Brilliant Blue R Using Organometallic Silver Nanoparticles Synthesized through a Green Chemistry Method.

Nowadays, nanostructures having tremendous chemical and physical properties are gaining attention in the biomedical industry. However, when they are prepared through classical methods (physical and chemical), they are often non-biocompatible and toxic. Considering the mentioned factors, in this research, organometallic silver nanostructures (OMAgNs) have been prepared by the green chemistry method using the acetone, methanol, and methanol-hexane-based extracts of the medicinally important plant Cichorium intybus. Secondary metabolites from C. intybus can be used as an alternative to synthetic reagents at an industrial scale to manufacture biosafe and economical nanostructures with enhanced physicochemical parameters. Prepared nanostructures were characterized using SEM, XRD, FTIR, TGA, UV, and zeta potential measurement. SEM analysis revealed different shapes of OMAgNs, prepared with various extracts. XRD analysis showed the crystallinity of the nanostructures. FTIR spectroscopy helped to identify groups of compounds present in the extracts and used for the OMAgNs synthesis. Out of the three tested OMAgNs, those prepared with methanol extract were selected due to the highest obtained yield and stability (highest negative zeta potential) and were tested as a cost-efficient and active agent to photodegrade organic pollutant, Brilliant Blue R, using energy from sunlight. A decrease in UV-VIS absorbance confirmed the rapid degradation of the dye.

Carbon Nanotubes Interference with Luminescence-Based Assays.

Carbon nanotubes (CNTs) are one of the most promising nanomaterials synthesized to date. Thanks to their unique mechanical, electronic, and optical properties, they have found a wide application in electronics in the production of biosensors and nanocomposites. The functionalization of multiwalled carbon nanotubes (MWCNTs) is aimed at making them biocompatible by adding hydrophilic groups on their surface, increasing their solubility and thus rendering them applicable in the regenerative medicine. So far, there is conflicting information about carbon nanotubes in biological systems. This paper investigates the effect of functionalized, oxidized, multiwalled carbon nanotubes (MWCNT-Ox) on the cytotoxicity of normal human articular chondrocytes (NHAC-kn cell line). Since absorbance-based and fluorescence-based assays were shown to interfere with carbon nanotubes, luminescence-based tests were carried out, as they work on a different method of detection and provide advantages over the mentioned ones. Cell viability and reactive oxygen species (ROS) tests were carried out. The cell viability assay showed that with the increasing MWCNTs concentration, the number of viable chondrocytes was significantly decreasing. Exposure to MWCNT-Ox indicated oxidative stress in the lowest investigated concentration with a decreased amount of ROS with higher concentrations. However, control experiments with adenosine triphosphate (ATP) and H2O2-molecules that are detected by the assays-showed that carbon nanotubes interfere directly with measurement, thus rendering the results unreliable. To understand the exact interference mechanisms, further studies must be taken. In conclusion, this study shows that luminescence-based tests yield erroneous results, confirming that in vitro experiments in the literature concerning carbon nanotubes should be analyzed with caution.

Utilization of Carbon Nanotubes in Manufacturing of 3D Cartilage and Bone Scaffolds.

Cartilage and bone injuries are prevalent ailments, affecting the quality of life of injured patients. Current methods of treatment are often imperfect and pose the risk of complications in the long term. Therefore, tissue engineering is a rapidly developing branch of science, which aims at discovering effective ways of replacing or repairing damaged tissues with the use of scaffolds. However, both cartilage and bone owe their exceptional mechanical properties to their complex ultrastructure, which is very difficult to reproduce artificially. To address this issue, nanotechnology was employed. One of the most promising nanomaterials in this respect is carbon nanotubes, due to their exceptional physico-chemical properties, which are similar to collagens-the main component of the extracellular matrix of these tissues. This review covers the important aspects of 3D scaffold development and sums up the existing research tackling the challenges of scaffold design. Moreover, carbon nanotubes-reinforced bone and cartilage scaffolds manufactured using the 3D bioprinting technique will be discussed as a novel tool that could facilitate the achievement of more biomimetic structures.

Potential use of superparamagnetic iron oxide nanoparticles for in vitro and in vivo bioimaging of human myoblasts.

Myocardial infarction (MI) is one of the most frequent causes of death in industrialized countries. Stem cells therapy seems to be very promising for regenerative medicine. Skeletal myoblasts transplantation into postinfarction scar has been shown to be effective in the failing heart but shows limitations such, e.g. cell retention and survival. We synthesized and investigated superparamagnetic iron oxide nanoparticles (SPIONs) as an agent for direct cell labeling, which can be used for stem cells imaging. High quality, monodisperse and biocompatible DMSA-coated SPIONs were obtained with thermal decomposition and subsequent ligand exchange reaction. SPIONs' presence within myoblasts was confirmed by Prussian Blue staining and inductively coupled plasma mass spectrometry (ICP-MS). SPIONs' influence on tested cells was studied by their proliferation, ageing, differentiation potential and ROS production. Cytotoxicity of obtained nanoparticles and myoblast associated apoptosis were also tested, as well as iron-related and coating-related genes expression. We examined SPIONs' impact on overexpression of two pro-angiogenic factors introduced via myoblast electroporation method. Proposed SPION-labeling was sufficient to visualize firefly luciferase-modified and SPION-labeled cells with magnetic resonance imaging (MRI) combined with bioluminescence imaging (BLI) in vivo. The obtained results demonstrated a limited SPIONs' influence on treated skeletal myoblasts, not interfering with basic cell functions.

Surface topography analysis with application of roughness area dependence method.

At the moment the root mean square roughness (Rq) is the most commonly used parameter for quantitative description of surface properties. However, this parameter has one main disadvantage: for its calculation only height variations of surface profile are used which are then represented by a single number. To eliminate this restriction authors of the paper have developed a surface analysis method which is based on roughness calculation in the function of gradually increasing dimensions of a sampling area. By setting proper measurement parameters and further data processing, from Rq dependence on sampling area plot size there is a possibility to obtain more useful, additional information about specific surface properties than using the single roughness value. Roughness area dependence plots, obtained from AFM images, were analyzed to study the influence of different growth parameters on surface properties of GaN layers and AlGaN/GaN heterostructures grown on sapphire and silicon substrates by Metal Organic Chemical Vapor Deposition (MOVPE) epitaxy. Although the method was used to characterize the semiconductor material in micrometer range, it can be applied also for any topography imaging technique in wide scale ranges.