Super-Resolution STED Microscopy in live Brain Tissue

STED microscopy is one of several fluorescence microscopy techniques that permit imaging at higher spatial resolution than what the diffraction-limit of light dictates. STED imaging is unique among these super-resolution modalities in being a beam-scanning microscopy technique based on confocal or 2-photon imaging, which provides the advantage of superior optical sectioning in thick samples. Compared to the other super-resolution techniques that are based on widefield microscopy, this makes STED particularly suited for imaging inside live brain tissue, such as in slices or in vivo. Notably, the 50nm resolution provided by STED microscopy enables analysis of neural morphologies that conventional confocal and 2-photon microscopy approaches cannot resolve, including all-important synaptic structures. Over the course of the last 20years, STED microscopy has undergone extensive developments towards ever more versatile use, and has facilitated remarkable neurophysiological discoveries. The technique is still not widely adopted for live tissue imaging, even though one of its particular strengths is exactly in resolving the nanoscale dynamics of synaptic structures in brain tissue, as well as in addressing the complex morphologies of glial cells, and revealing the intricate structure of the brain extracellular space. Not least, live tissue STED microscopy has so far hardly been applied in settings of pathophysiology, though also here it shows great promise for providing new insights. This review outlines the technical advantages of STED microscopy for imaging in live brain tissue, and highlights key neurobiological findings brought about by the technique.The authors acknowledge funding for their general work from the Spanish Ministry of Science and Innovation (SAF-2017-83776-R, RYC-2014-15994 and IJCI-2017-32114), the Basque Government (PIBA19-0065 and PIBA-2020-1-0061), and the University of the Basque Country (GIU18/094 and INF19-29

Assessing the Impact of Sepiolite-Based Bio-Pigment Infused with Indigo Extract on Appearance and Durability of Water-Based White Primer

The objective of this study is to evaluate how two varying amounts of sepiolite-based powder, infused with indigo extract, affect the appearance and durability of a water-based, white primer. To examine the influence of this eco-friendly pigment on the coatings’ overall appearance, assessments were performed for color, gloss, and surface roughness. Additionally, the coatings were investigated through optical and electron microscopic observations, to evaluate the distribution of the pigment within the polymer matrix. The effect of the pigment on the coating’s durability was assessed through accelerated tests, including exposure in a salt spray chamber and a UV-B chamber. These tests aimed to evaluate the emergence of defects and changes in the appearance of the samples over time. Furthermore, the impact of different quantities of sepiolite-based powder on the coating’s ability to act as a barrier was assessed using liquid resistance tests and contact angle measurements. These evaluations aimed to understand how the coating responded to various liquids and its surface properties concerning repellency or absorption. In essence, this study underscores the considerable influence of the eco-friendly pigment, demonstrating its capacity to introduce unique color and texture variations in the paint. Moreover, the inclusion of the pigment has enhanced the coating’s color stability, its ability to act as a barrier, and its overall durability when exposed to harsh environments

Eco-Friendly Multilayer Coating Harnessing the Functional Features of Curcuma-Based Pigment and Rice Bran Wax as a Hydrophobic Filler

This work aims to highlight the multiple features shown by curcuma-based pigment and rice bran wax, which can be selectively employed as bio-based additives for the realization of multilayer wood coatings with multiple functionalities, harnessing the capabilities of the two environmentally friendly fillers, in line with current environmental sustainability trends. The role of the two green materials on the morphology of the composite layers was examined through observations employing scanning electron and optical microscopy, revealing a strong alteration of the film’s appearance, both its color and reflectivity. Additionally, their influence on the paint’s resilience was assessed by exposing the samples to UV-B radiation and consecutive thermal shocks. The coating displayed a clear and uniform change in color because of substantial curcuma powder photo-degradation but it remained exceptionally stable when subjected to thermal stresses. Moreover, the protective properties of the coatings were evaluated by conducting liquid resistance tests and water uptake tests, while the hardness and the abrasion resistance of the coatings were assessed to evaluate the effect of the additives on the mechanical properties of the coatings. In conclusion, this study showcases the promising joint action of curcuma-based pigment and rice bran wax in multilayer coatings. This combination offers vibrant yellow tones and an appealing appearance to the paint, enhances the surface’s water-repellent properties, and improves the mechanical resistance of the coatings

Durability and Thermal Behavior of Functional Paints Formulated with Recycled-Glass Hollow Microspheres of Different Size

This study aims to assess the effect of hollow glass microspheres of different sizes derived from glass industry waste on the durability and thermal behavior of waterborne paint. The coatings were characterized by electron microscopy to investigate the distribution of the spheres and their influence on the layer morphology. The impact of the various glassy spheres on the mechanical feature of the coatings was assessed using the Buchholz hardness test and the Scrub abrasion test. The role of the spheres in altering the durability of the samples was analyzed by the salt spray exposure test and the electrochemical impedance spectroscopy measurements. Finally, a specific accelerated degradation test was carried out to explore the evolution of the thermal behavior of the composite coatings. Ultimately, this work revealed the pros and cons of using hollow glass spheres as a multifunctional paint filler, highlighting the size of the spheres as a key parameter. For example, spheres with adequate size (25–44 µm), totally embedded in the polymeric matrix, are able to reduce the thermal conductivity of the coating avoiding local heat accumulation phenomena

Functional Olive Pit Powders: The Role of the Bio-Based Filler in Reducing the Water Uptake Phenomena of the Waterborne Paint

In this study, olive pit powders were added to a polyurethane-acrylate paint for examining the impact of two alternative functionalization processes in increasing the filler hydrophobicity in an effort to increase the durability of the paint. In order to look into potential changes in morphology and appearance owing to the surface conversion treatments of the two bio-based additives, the coatings were examined using electron microscopy and colorimetric tests. The coating’s resilience and the hydrophobic/hydrophilic role of the fillers were evaluated by salt spray chamber exposure, contact angle measurements, paint liquid resistance, UV-B exposure, and electrochemical impedance spectroscopy measurements, which highlighted the reduction in water absorption inclination of the filler made of lignocellulose due to the silane and wax functionalization. This study demonstrated that the bio-based filler, if properly functionalized, can actually be implemented as multifunctional pigment in waterborne paints, giving specific aesthetic characteristics, but also improving the barrier performance of the polymeric matrix and increasing the durability of the composite coating

Powder Coating for Healthcare Aluminum Packaging

Restrictive regulations concerning the toxicity of certain compounds and the use and disposal of solvents present in the liquid epoxy protection system have been analyzed in this work to evaluate powder coatings as an alternative in the protection of aerosol aluminum cans, which are employed in cosmetics and pharmaceutical product packaging. In this paper, the chemical resistance of polyester and mixed epoxy-polyester powder coatings is assessed, considering different aggressive environments employed in healthcare commercial products. The samples’ performances are also compared with the currently used liquid organic coatings. The pack test has been used to evaluate the protective system behavior in contact with both the liquid and the gaseous part of the cosmetic product. However, the visual observation, required by the test, enabled the highlight of only very evident degradation phenomena. The chemical resistance of the powder coatings has proved to be appropriate only for less aggressive environment, where the critical compounds are propellants, propane, butane and isobutane. When exposed to other environments containing alcohol, water and dimethyl ether, most samples have been susceptible to layer degradation phenomena. Polyester layers lose their corrosion protection properties. Epoxy systems, instead, result more performant than polyester resins, but they particularly suffer from the contact with dimethyl ether

Microglia and the Purinergic Signaling System

Microglia are the main resident immune-competent cell type of the central nervous system (CNS); these cells are highly sensitive to subtle changes in the chemical environment of the brain. Microglia are activated during diverse conditions, such as apoptosis, trauma, inflammation, and infection. The specific activities of microglia result from the confluence of environmental stimuli and the cellular state. It is likely that several signaling systems with different biological functions operate in competition and/or synergy, thus regulating similar microglial behaviors. The purinergic system is one of the fundamental signaling systems that establish microglial behavior in a wide spectrum of conditions. Adenosine tri-phosphate (ATP) belongs to the purinergic signaling system, which includes P2X, P2Y, and P1 receptors, as well as other proteins participating in ATP secretion and extracellular ATP degradation, and molecules that recognize purines as a ligand. In this review, we focus on the latest pre-clinical and basic purinergic system and microglial research, with particular attention to data collected in vivo and ex vivo. This chapter is divided into sections related to microglial ATP release, ATP degradation, and ATP-related actions mediated by P2X and P2Y receptor activation

The Influence of NIR Pigments on Coil Coatings’ Thermal Behaviors

The effect of over-heating in urban areas, called the urban heat island effect (UHI effect), is responsible for greater energy consumption for cooling buildings. Several reflective near-infrared (NIR) coatings, called cool coatings have proved to be effective for contrasting the UHI effect. The thermal and appearance properties of cool coatings depend on the color and they often have been studied only at the initial state, without undergoing atmospheric degradation and soiling. In this work, the thermal, visual and durability behaviors of red and brown polyester-based organic coatings for roof applications were studied. All samples were subjected to accelerated degradation cycles composed of UV-B and salt spray chamber exposure. The sample degradation was assessed by infrared spectroscopy, gloss and colorimetric analyses. Moreover, the thermal behavior was studied by means of a simplified experimental setup. Finally, a soiling and weathering test was conducted to simulate the soiling of three years’ external exposure. Despite the phenomena of chemical degradation and a decrease in aesthetic properties, the samples maintain their thermal performance, which is not even influenced by dirt products. In addition, NIR pigments significantly improve the thermal behavior of brown coatings

Antimicrobial Performance of Innovative Functionalized Surfaces Based on Enamel Coatings: The Effect of Silver-Based Additives on the Antibacterial and Antifungal Activity

Frequently touched surfaces (FTS) that are contaminated with pathogens are one of the main sources of nosocomial infections, which commonly include hospital-acquired and healthcare-associated infections (HAIs). HAIs are considered the most common adverse event that has a significant burden on the public’s health worldwide currently. The persistence of pathogens on contaminated surfaces and the transmission of multi-drug resistant (MDR) pathogens by way of healthcare surfaces, which are frequently touched by healthcare workers, visitors, and patients increase the risk of acquiring infectious agents in hospital environments. Moreover, not only in hospitals but also in high-traffic public places, FTS play a major role in the spreading of pathogens. Consequently, attention has been devoted to developing novel and alternative methods to tackle this problem. This study planned to produce and characterize innovative functionalized enameled coated surfaces supplemented with 1% AgNO3 and 2% AgNO3. Thus, the antimicrobial properties of the enamels against relevant nosocomial pathogens including the Gram-positive Staphylococcus aureus and the Gram-negative Escherichia coli and the yeast Candida albicans were assessed using the ISO:22196:2011 norm