Influence of particle size on the SARS-CoV-2 spike protein detection using IgG-capped gold nanoparticles and dynamic light scattering.

Due to the unprecedented and ongoing nature of the coronavirus outbreak, the development of rapid immunoassays to detect severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) and its highly contagious variants is an important and challenging task. Here, we report the development of polyclonal antibody-functionalized spherical gold nanoparticle biosensors as well as the influence of the nanoparticle sizes on the immunoassay response to detect the SARS-CoV-2 spike protein by dynamic light scattering. By monitoring the increment in the hydrodynamic diameter (ΔDH) by dynamic light scattering measurements in the antigen-antibody interaction, SARS-CoV-2 S-protein can be detected in only 5 min. The larger the nanoparticles, the larger ΔDH in the presence of spike protein. From adsorption isotherm, the calculated binding constant (K D ) was 83 nM and the estimated limit of detection was 13 ng/mL (30 pM). The biosensor was stable up to 90 days at 4 °C. Therefore, the biosensor developed in this work could be potentially applied as a fast and sensible immunoassay to detect SARS-CoV-2 infection in patient samples.

A review of LCA assessments of forest-based bioeconomy products and processes under an ecosystem services perspective.

The emergence of politically driven bioeconomy strategies worldwide calls for considering the ecological issues associated with bio-based products. Traditionally, life cycle analysis (LCA) approaches are key tools used to assess impacts through product life cycles, but they present limitations regarding the accounting of multiple ecosystem service-related issues, at both the land-use and supply chain levels. Based on a systematic review of empirical articles, this study provides insights on using LCA assessments to account for ecosystem service-related impacts in the context of bioeconomy activities. We address the following research questions: what is the state of the art of the literature performing LCA assessments of forest-based bioeconomy activities, including the temporal distribution, the geographic areas and products/processes at study, and the approaches and methods used? 2. Which impacts and related midpoints are considered by the reviewed studies and what types of ecosystem service- related information do they bear? Out of over 600 articles found through the Scopus search, 155 were deemed relevant for the review. The literature focuses on North-America and Europe. Most of the articles assessed the environmental impact of lower-value biomass uses. Climate change was assessed in over 90% of the studies, while issues related to ozone, eutrophication, human toxicity, resource depletion, acidification, and environmental toxicity were assessed in 40% to 60% of the studies. While the impact categories accounted for in the reviewed LCA studies bear information relevant to certain provisioning and regulating services, several ecosystem services (especially cultural ones) remain unaccounted for. The implications of our study are relevant for professionals working in the ecosystem services, circular bioeconomy, and/or LCA communities.

Differential cellular analysis of bronchoalveolar lavage fluid obtained at various stages during the development of bleomycin-induced pulmonary fibrosis in the rat.

The purpose of this study was to analyze the cellular components of bronchoalveolar lavage fluid throughout the development of bleomycin-induced pulmonary fibrosis in the rat. Animals were killed and lavaged at various times after the administration of a single intratracheal injection of bleomycin. The results demonstrate that a significant influx of inflammatory cells appear in the lavage fluid as early as Day 1 after bleomycin treatment. Polymorphonuclear leukocytes are the first cells to appear and significant concentrations persist for as long as 1 month after bleomycin treatment. There is a very transient yet significant influx of eosinophils on Day 7 after bleomycin treatment. Lymphocytes are present from 3 to 14 days after bleomycin treatment; greater than 97% are T-cells and less than 3% are B-cells. There is a 1:1 ratio of W3/25+ cells (helper cell activity) to OX8+ cells (suppressor cell activity) comprising the lymphocyte population. The blood and lymphoid tissue of these animals contain a normal 2:1 ratio of these subsets. The data demonstrate that specific T-cell populations are present in the air spaces of the lung in response to bleomycin-induced pulmonary fibrosis in this model.

Continuous in vivo recordings of intraocular capillary and aqueous humor flows.

Multiple-point recordings of the initial slopes of xenon 133 and human serum albumin I125 washout from various ocular regions were utilized to visualize changes in capillary and aqueous humor bulk flow in vivo. Preservation of slope linearity is essential for sensitive responsiveness of recordings to flow change. Linearity is enhanced by the initial slope approach in which stability of physiological values and drug effects are maintained and slopes are closely fitted to multiple points. As examples of intraocular flow changes which may be observed and computed from such slopes, responses recorded in forty feline washout studies are presented and the fundamentals of washout recording interpretation are discussed.

Application of a minicomputer-based system in measuring intraocular fluid dynamics.

A complete, computerized system has been developed to automate and display radionuclide clearance studies in an ophthalmology clinical laboratory. The system is based on a PDP-8E computer with a 16-k core memory and includes a dual-drive Decassette system and an interactive display terminal. The software controls the acquisition of data from an NIM scaler, times the procedures, and analyzes and simultaneously displays logarithmically converted data on a fully annotated graph. Animal studies and clinical experiments are presented to illustrate the nature of these displays and the results obtained using this automated eye physiometer.

Emergency management of acute congestive glaucoma using an anterior chamber microsyringe and needle.

A microsyringe-needle assembly is described for use in aspiration and microinfusion procedures in the anterior chamber. Assets of a lancet pointed 30-gauge needle, surface anesthesia, and fine control of ocular pressure and aqueous humor volume are stressed. Use of the assembly for emergency treatment of acute congestive glaucoma, surgical paracentesis, aqueous sampling, and drug infusion are described. Drug volumes and concentrations must be maintained at levels which do not damage corneal endothelium.