New particle formation (NPF) is considered a major source of aerosol particles and cloud condensation nuclei (CCN); however, our understanding of NPF and the subsequent particle growth mechanisms in coastal areas remains limited. This study provides evidence of frequent NPF events followed by particle growth in the middle Adriatic Sea during the summer months at the coastal station of Rogoznica in Croatia. To our knowledge, this is the first study to report such events in this region.
View Article and Find Full Text PDFRapid and reliable immunosensing is undoubtedly one of the priorities in the efficient management and combat against a pandemic, as society has experienced with the SARS-CoV-2 outbreak; simple and cost-effective sensing strategies are at the forefront of these efforts. In this regard, 2D-layered MXenes hold great potential for electrochemical biosensing due to their attractive physicochemical properties. Herein, we present a VCT MXene-based sensing layer as an integral part of a label-free immunosensor for sensitive and selective detection of the SARS-CoV-2 spike protein.
View Article and Find Full Text PDFListeriosis is one of the most serious foodborne diseases caused by the intracellular bacterium Listeria monocytogenes. Its two major virulence factors, broad-range phospholipase C (LmPC-PLC) and the pore-forming toxin listeriolysin O (LLO), enable the bacterium to spread in the host by destroying cell membranes. Here, we determine the crystal structure of LmPC-PLC and complement it with the functional analysis of this enzyme.
View Article and Find Full Text PDFSpinal cord injury (SCI) is a life-altering event, which often results in loss of sensory and motor function below the level of trauma. Biomaterial therapies have been widely investigated in SCI to promote directional regeneration but are often limited by their pre-constructed size and shape. Herein, the design parameters of microporous annealed particles (MAPs) are investigated with tubular geometries that conform to the injury and direct axons across the defect to support functional recovery.
View Article and Find Full Text PDFThe development of sensitive, selective, and reliable gaseous hydrogen peroxide (HO) sensors operating at room temperature still represents a remaining challenge. In this work, we have investigated and combined the advantageous properties of a two-dimensional TiCT MXene material that exhibits a large specific surface area and high surface activity, with favorable conducting and stabilizing properties of chitosan. The MXene-chitosan membrane was deposited on the ferrocyanide-modified screen-printed working carbon electrode, followed by applying poly(acrylic acid) as an electrolyte and accumulation medium for gaseous HO.
View Article and Find Full Text PDFEngineered gold nanoparticles (GNPs) have become a useful tool in various therapeutic and diagnostic applications. Uncertainty remains regarding the possible impact of GNPs on the immune system. In this regard, we investigated the interactions of polymer-coated GNPs with B cells and their functions in mice.
View Article and Find Full Text PDFCan the advantage of risk-managing life-history strategies become a disadvantage under human-induced evolution? Organisms have adapted to the variability and uncertainty of environmental conditions with a vast diversity of life-history strategies. One such evolved strategy is multiple-batch spawning, a spawning strategy common to long-lived fishes that 'hedge their bets' by distributing the risk to their offspring on a temporal and spatial scale. The fitness benefits of this spawning strategy increase with female body size, the very trait that size-selective fishing targets.
View Article and Find Full Text PDFThe preconditioning and modification of the supporting electrode surface is an essential step in every biosensor architecture. In particular, when using screen-printed carbon electrodes (SPEs) as inexpensive and convenient disposable sensor substrates, their somewhat lower electrochemical (surface) reproducibility might represent a complex hurdle. Herein, we investigated the effect of selected preconditioning strategies, such as cyclic voltammetric pretreatment, in HSO and HO and plasma pretreatment with a positive and negative glow discharge, which all improved the electrochemical stability of the unmodified SPEs.
View Article and Find Full Text PDFAtmospheric gases and particulate matter (PM) in contact with the material's surface lead to chemical and physical changes, which in most cases cause degradation of the cultural heritage material. Atmospheric damage and soiling are recognized as two pivotal forms of deterioration of cultural heritage materials caused by air pollution. However, the atmospheric damage effect of PM is rather complicated; its variable composition accelerates the deterioration process.
View Article and Find Full Text PDFFisheries exploitation can cause genetic changes in heritable traits of targeted stocks. The direction of selective pressure forced by harvest acts typically in reverse to natural selection and selects for explicit life histories, usually for younger and smaller spawners with deprived spawning potential. While the consequences that such selection might have on the population dynamics of a single species are well emphasized, we are just beginning to perceive the variety and severity of its propagating effects within the entire marine food webs and ecosystems.
View Article and Find Full Text PDFStochastic environments shape life-history traits and can promote selection for risk-spreading strategies, such as bet-hedging. Although the strategy has often been hypothesized to exist for various species, empirical tests providing firm evidence have been rare, mainly due to the challenge in tracking fitness across generations. Here, we take a 'proof of principle' approach to explore whether the reproductive strategy of multiple-batch spawning constitutes a bet-hedging.
View Article and Find Full Text PDFInner ear organoids derived from pluripotent stem cells could be a useful model system to study development, disease, and regeneration. However, there is considerable heterogeneity in the size, morphology, and efficiency of organoid production using standard protocols. Greater control of the culture microenvironment could decrease heterogeneity and increase the yield of organoids.
View Article and Find Full Text PDFNanoparticle-based delivery systems for cancer immunotherapies aim to improve the safety and efficacy of these treatments through local delivery to specialized antigen-presenting cells (APCs). Multifunctional mesoporous silica nanoparticles (MSNs), with their large surface areas, their tunable particle and pore sizes, and their spatially controlled functionalization, represent a safe and versatile carrier system. In this study, we demonstrate the potential of MSNs as a pH-responsive drug carrier system for the anticancer immune-stimulant R848 (resiquimod), a synthetic Toll-like receptor 7 and 8 agonist.
View Article and Find Full Text PDFIn mammals, spinal cord injuries often result in muscle paralysis through the apoptosis of lower motor neurons and denervation of neuromuscular junctions. Previous research shows that the inflammatory response to a spinal cord injury can cause additional tissue damage after the initial trauma. To modulate this inflammatory response, we delivered lentiviral anti-inflammatory interleukin-10, via loading onto an implantable biomaterial scaffold, into a left-sided hemisection at the C5 vertebra in mice.
View Article and Find Full Text PDFThe detection of volatile organic compounds with electrochemical gas sensors is still very challenging regarding their sensitivity, selectivity, and operation at room temperature. There is a need for robust, sensitive, inexpensive, and yet easy-to-operate sensors for phenol and other phenolic compounds that function reliably under ambient conditions. Herein, we present a phenol gas sensor based on a combination of a semisolid, alkaline sodium polyacrylate, and commercial screen-printed electrodes.
View Article and Find Full Text PDFJ Biochem Mol Toxicol
November 2020
Perfluoroalkyl substances, such as perfluorooctanoic acid (PFOA), are widely used in consumer and industrial applications. Human epidemiologic and animal studies suggest that PFOA exposure elicits adverse effects on the pancreas; however, little is known about the biological effects of PFOA in this organ. In this study, we show that PFOA treatment of mouse pancreatic acinar cells results in endoplasmic reticulum (ER) stress and activation of the protein kinase-like endoplasmic reticulum kinase (PERK), inositol-requiring kinase/endonuclease 1α (IRE1α), and activating transcription factor 6 arms of the unfolded protein response (UPR) pathway.
View Article and Find Full Text PDFMMWR Morb Mortal Wkly Rep
January 2020
Gold nanoparticles (GNPs) are intended for use within a variety of biomedical applications due to their physicochemical properties. Although, in general, biocompatibility of GNPs with immune cells such as macrophages and dendritic cells is well established, the impact of GNPs on B lymphocyte immune function remains to be determined. Since B lymphocytes play an important role in health and disease, the suitability of GNPs as a B cell-targeting tool is of high relevance.
View Article and Find Full Text PDFResiquimod (R848), a member of the imidazoquinoline family, is a Toll-like receptor 7/8 agonist with high potency for cancer immunotherapy. However, tolerance induction and adverse effects limit its development as a drug. Encapsulation in a polymer matrix can circumvent these limitations, as shown in our formerly published approach where R848 was loaded into polylactic acid (PLA)-based nanoparticles (NP).
View Article and Find Full Text PDFProgesterone is an important hormone responsible, among others, for maintaining pregnancy via inhibition of uterus muscles activity; thus, following its concentration levels in pregnant women is of immense importance in the endeavor to prevent premature birth. In this work, the nanostructured bismuth film electrode (nsBiFE) was studied for detection of progesterone in neutral medium. Due to the ability to accumulate progesterone at the nsBiFE, the adsorptive cathodic stripping voltammetry was beneficially exploited.
View Article and Find Full Text PDFIridium-based particles, regarded as the most promising proton exchange membrane electrolyzer electrocatalysts, were investigated by transmission electron microscopy and by coupling of an electrochemical flow cell (EFC) with online inductively coupled plasma mass spectrometry. Additionally, studies using a thin-film rotating disc electrode, identical location transmission and scanning electron microscopy, as well as X-ray absorption spectroscopy have been performed. Extremely sensitive online time-and potential-resolved electrochemical dissolution profiles revealed that Ir particles dissolve well below oxygen evolution reaction (OER) potentials, presumably induced by Ir surface oxidation and reduction processes, also referred to as transient dissolution.
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