Search

Autoimmune diseases, allergies, transplant rejections, generation of antidrug antibodies, and chronic inflammatory diseases have impacted a large group of people across the globe. Conventional treatments and therapies often use systemic or broad immunosuppression with serious efficacy and safety issues. Tolerogenic vaccines represent a concept that has been extended from their traditional immune-modulating function to induction of antigen-specific tolerance through the generation of regulatory T cells. Without impairing immune homeostasis, tolerogenic vaccines dampen inflammation and induce tolerogenic regulation. However, achieving the desired potency of tolerogenic vaccines as preventive and therapeutic modalities calls for precise manipulation of the immune microenvironment and control over the tolerogenic responses against the autoantigens, allergens, and/or alloantigens. Engineered nano-/microparticles possess desirable design features that can bolster targeted immune regulation and enhance the induction of antigen-specific tolerance. Thus, particle-based tolerogenic vaccines hold great promise in clinical translation for future treatment of aforementioned immune disorders. In this review, we highlight the main strategies to employ particles as exciting tolerogenic vaccines, with a focus on the particles' role in facilitating the induction of antigen-specific tolerance. We describe the particle design features that facilitate their usage and discuss the challenges and opportunities for designing next-generation particle-based tolerogenic vaccines with robust efficacy to promote antigen-specific tolerance for immunotherapy.

Extracellular vesicles (EVs), through their complex cargo, can reflect the state of their cell of origin and change the functions and phenotypes of other cells. These features indicate strong biomarker and therapeutic potential and have generated broad interest, as evidenced by the steady year-on-year increase in the numbers of scientific publications about EVs. Important advances have been made in EV metrology and in understanding and applying EV biology. However, hurdles remain to realising the potential of EVs in domains ranging from basic biology to clinical applications due to challenges in EV nomenclature, separation from non-vesicular extracellular particles, characterisation and functional studies. To address the challenges and opportunities in this rapidly evolving field, the International Society for Extracellular Vesicles (ISEV) updates its Minimal Information for Studies of Extracellular Vesicles, which was first published in 2014 and then in 2018 as MISEV2014 and MISEV2018, respectively. The goal of the current document, MISEV2023, is to provide researchers with an updated snapshot of available approaches and their advantages and limitations for production, separation and characterisation of EVs from multiple sources, including cell culture, body fluids and solid tissues. In addition to presenting the latest state of the art in basic principles of EV research, this document also covers advanced techniques and approaches that are currently expanding the boundaries of the field. MISEV2023 also includes new sections on EV release and uptake and a brief discussion of in vivo approaches to study EVs. Compiling feedback from ISEV expert task forces and more than 1000 researchers, this document conveys the current state of EV research to facilitate robust scientific discoveries and move the field forward even more rapidly.

Endothelial dysfunction exacerbates hypertension and other vascular complications in diabetes mellitus (DM). Circulating microparticles (MPs) and extracellular vesicles released in patients with DM have emerged as novel regulators of endothelial dysfunction. The obstruction of mineralocorticoid receptors (MRs) is a potential therapeutic approach to reduce cardiovascular complications. Their impact on the obstruction of MRs on circulating MPs and endothelial dysfunction in DM remains unclear. DM was induced in mice through a single intravenous dose of streptozotocin (STZ; 200 mg/kg). Esaxerenone (ESAX; 3 mg/kg/day), a MR blocker was administered via diet for 8 weeks. In this study, the aortas of the DM group showed the endothelial dysfunction and the administration of ESAX ameliorated the endothelial-dependent responses. Moreover, ESAX influences the impaired endothelial-dependent responses of DM-derived MPs. Interestingly, MP levels increased in DM whereas decreased after ESAX administration. In the aorta, the DM-derived MPs increased the expression of intercellular adhesion molecule-1 (ICAM-1). ESAX inhibited the adhesion of DM-derived MPs. Moreover, the ICAM-1 inhibitor A205804 shows similar effects as ESAX. These results indicate that the release and adhesion properties of MPs can be partially obstructed by ESAX via the ICAM-1 signaling pathway, which clarifies the other functions beyond the anti-hypertensive effects of ESAX. [ABSTRACT FROM AUTHOR]

To detect cellular activities deep within the body using magnetic resonance platforms, magnetosomes are the ideal model of genetically-encoded nanoparticles. These membrane-bound iron biominerals produced by magnetotactic bacteria are highly regulated by approximately 30 genes; however, the number of magnetosome genes that are essential and/or constitute the root structure upon which biominerals form is largely undefined. To examine the possibility that key magnetosome genes may interact in a foreign environment, we expressed mamI and mamL as fluorescent fusion proteins in mammalian cells. Localization and potential protein-protein interaction(s) were investigated using confocal microscopy and fluorescence correlation spectroscopy (FCS). Enhanced green fluorescent protein (EGFP)-MamI and the red fluorescent Tomato-MamL displayed distinct intracellular localization, with net-like and punctate fluorescence, respectively. Remarkably, co-expression revealed co-localization of both fluorescent fusion proteins in the same punctate pattern. An interaction between MamI and MamL was confirmed by co-immunoprecipitation. In addition, changes in EGFP-MamI distribution were accompanied by acquisition of intracellular mobility which all Tomato-MamL structures displayed. Analysis of extracts from these cells by FCS was consistent with an interaction between fluorescent fusion proteins, including an increase in particle radius. Co-localization and interaction of MamI and MamL demonstrate that select magnetosome proteins may associate in mammalian cells. [ABSTRACT FROM AUTHOR]

The current work aims to develop a bigel-containing clobetasol propionate-loaded PLGA microparticles and further assess its in vitro, ex vivo, and in vivo behavior for psoriasis management. PLGA microparticles (2%w/w) containing clobetasol propionate were developed by solvent evaporation technique. For the developed particles, size, drug loading, entrapment efficiency, and surface morphology were determined. Further, the particles were suspended into bigel developed from oleogel and hydrogel (40:60) and assessed for stability, in vitro drug release, ex vivo skin permeation, retention, and in vivo study in BALB c mice for antipsoriatic potential. PLGA microparticles developed by solvent evaporation were found to have a mean particle size of 19.45 ± 1.74 μm. Drug loading and entrapment efficiency for clobetasol were found to be 43.5 ± 4.94% and 94.5 ± 3.68%, respectively. For the developed bigel, sustained in vitro drug release was observed till 7 h. Ex vivo skin permeation with the developed formulation was found to be higher than the marketed formulation and drug suspended in bigel. A retention study performed on pig skin suggested the topical skin retention of the drug. Further, the psoriatic model was developed in BALB c mice with IMQ cream, and it was observed that the developed formulation helped considerably reduce the irritation score and PASI scoring in mice as compared to the standard treatment. The same is corroborated with the help of histopathological studies performed by Hematoxylin and Eosin (H&E) staining in the same animals. The study findings suggest that clobetasol microparticle-loaded bigel formulation appeared to be a promising therapy option for psoriasis. [ABSTRACT FROM AUTHOR]

The combination of paclitaxel (PTX) with other chemotherapy drugs (e.g., gemcitabine, GEM) or genetic drugs (e.g., siRNA) has been shown to enhance therapeutic efficacy against tumors, reduce individual drug dosages, and prevent drug resistance associated with single-drug treatments. However, the varying solubility of chemotherapy drugs and genetic drugs presents a challenge in co-delivering these agents. In this study, nanoparticles loaded with PTX were prepared using the biodegradable polymer material poly(3-hydroxybutyrate-co-3-hydroxyhexanoate) (PHBHHx). These nanoparticles were surface-modified with target proteins (Affibody molecules) and RALA cationic peptides to create core-shell structured microspheres with targeted and cationic functionalization. A three-drug co-delivery system (PTX@PHBHHx-ARP/siRNAGEM) were developed by electrostatically adsorbing siRNA chains containing GEM onto the microsphere surface. The encapsulation efficiency of PTX in the nanodrug was found to be 81.02%, with a drug loading of 5.09%. The chemogene adsorption capacity of siRNAGEM was determined to be 97.3%. Morphological and size characterization of the nanodrug revealed that PTX@PHBHHx-ARP/siRNAGEM is a rough-surfaced microsphere with a particle size of approximately 150 nm. This nanodrug exhibited targeting capabilities toward BT474 cells with HER2 overexpression while showing limited targeting ability toward MCF-7 cells with low HER2 expression. Results from the MTT assay demonstrated that PTX@PHBHHx-ARP/siRNAGEM exhibits high cytotoxicity and excellent combination therapy efficacy compared to physically mixed PTX/GEM/siRNA. Additionally, Western blot analysis confirmed that siRNA-mediated reduction of Bcl-2 expression significantly enhanced cell apoptosis mediated by PTX or GEM in tumor cells, thereby increasing cell sensitivity to PTX and GEM. This study presents a novel targeted nanosystem for the co-delivery of chemotherapy drugs and genetic drugs. [ABSTRACT FROM AUTHOR]

The demand for sustainable polymer particles production is growing, driven by the need for efficient, biocompatible, and biodegradable materials. In this context, the present study explores the production of poly(butylene succinate) (PBS) particles in a single step using a green heterogeneous suspension process, using vegetable oil as the suspending medium. Particularly, the effects of oil type (soybean, corn, sunflower), dispersed phase holdup (10–30 wt.%), stabilizers (Span 20, Span 80, Tween 80, Brij 52, Brij 93, Igepal‐co‐520,  Polyglycerol polyricinoleate (PGPR)), reaction time (1–5 h), and temperature (100–160 °C) on the suspension polymerization are investigated. Results indicate that particle size and shape are influenced by the vegetable oil and stabilizer. Additionally, it is shown that the particle size distribution is affected by the use of a sonicator, allowing the manufacture of even smaller microsized particles. Based on the results, a 30 wt.% holdup in corn oil with a blend of surfactants can be recommended, producing spherical particles with an average diameter of 100 µm. Moreover, higher reaction temperatures (160 °C) and longer reaction times (5 h) positively impacted the molar mass of the obtained particles. Finally, cytotoxicity tests using Bone Marrow‐Derived Macrophages cells confirmed the safe use of PBS microparticles at concentrations up to 1000 µg mL⁻¹ [ABSTRACT FROM AUTHOR]

This study explores the impact on the stability of drying and the encapsulation of a camu camu extract (CCX) using the non-thermal, high-throughput electrospraying assisted by pressurized gas (EAPG) technique. The dried and encapsulated products by the EAPG processing techniques were compared in terms of total soluble phenolic compounds, antioxidant activity, and storage stability. Whey protein concentrate (WPC) and zein (ZN) were selected as the protective excipients for encapsulation. Dried and encapsulated products were obtained in the form of microparticles, which were smaller and more spherical in the case of the encapsulates. No significant differences were observed in the total polyphenolic content (TSP), and only relatively small differences in the antioxidant capacity were measured among samples. The generated products were subjected to various storage conditions to assess their stability and the preservation of the TSP and the antioxidant properties, i.e., 0% relative humidity (RH) and 4 °C; 0% RH and 21 °C; 23% RH and 21 °C; 56% RH and 21 °C; and UV light exposure. The results indicated that ZN encapsulation notably enhanced the retention of total soluble polyphenols and the antioxidant activity compared to WPC and dried CCX, especially in the ratio of 2:1 (encapsulating polymer: dried CCX). This study demonstrates the potential of protein-based encapsulation, particularly using ZN, for stabilizing bioactive compounds against degradation mechanisms induced by humidity, temperature, or ultraviolet radiation exposure. [ABSTRACT FROM AUTHOR]

Porous organic cobaltocenium‐containing particles are scarce in literature but highly interesting for their electrochemical properties and reusability in, for example, catalysis or magnetic systems. In this work, we present a scalable one‐pot strategy to introduce tailorable amounts of cobaltocenium on a porous substrate, adjusting the electrochemical switching capability. For this purpose, 3‐(triethoxysilyl)propan‐1‐amine (APTES) and ethynyl cobaltocenium hexafluorophosphate is used as functionalization agents for in‐situ catalyst‐free hydroamination, followed by silane condensation at the particles' surface. Functionalized particles are characterized by attenuated total reflection infrared spectroscopy (ATR‐IR), thermogravimetric analysis (TGA), laser scanning confocal microscopy (LSCM), scanning electron microscopy (SEM), energy dispersive X‐ray spectroscopy (EDS), inductively coupled plasma mass spectrometry (ICP‐MS), powder X‐ray diffraction (PXRD) and cyclic voltammetry (CV) showing excellent control over the degree of functionalization, i. e., the added cobaltocenium reagents. The electrochemical stability and good addressability while preserving the porous structure are shown. By utilizing higher amounts of APTES, the overall cobaltocenium amount can be reduced in favor of additional amine groups, strongly affecting the electrochemical behavior, making this functionalization strategy a good platform for metallopolymer immobilization and tailored functionalization. Additionally, thermal treatment of the synthesized metallopolymer microparticles paves the way to magnetic properties with tailorable microporous architectures for end‐of‐life and upcycling aspects. [ABSTRACT FROM AUTHOR]

This study investigated the high‐intensity focused ultrasound (HIFU)‐mediated propulsion of mesoporous silica nanoparticles (MSNs) and microspheres (MSMs). Nanoparticles are heavily sought as vehicles for drug delivery, but their transport through tissue is often restricted. Here, MSNs and MSMs are hydrophobically modified and coated with phospholipids to facilitate inertial cavitation to promote propulsion under HIFU. Modified nanoparticles show significantly enhanced cavitation and propulsion, achieving a maximum displacement of 250 µm (≈2500 body length) and speed of ≈1600 µm s−1 (16 000 body length s−1), compared to unmodified nanoparticles (2 µm, 20 body length, 60 µm s−1, 600 body length). In contrast, microparticles demonstrate comparable cavitation responses. Modified microparticles reached a maximum speed of 4000 µm s−1 (800 body length s−1) and displacement of 230 µm (46 body length), and unmodified microparticles achieved 2000 µm s−1 (400 body length s−1) and 75 µm (15 body length). In all HIFU‐responsive samples, displacement and speed decreased with successive pulses, implying that particles fatigue with continued pulsing. Analyses of particle trajectories and rotational diffusion times suggest that cavitation occurs uniformly on particle surfaces rather than at specific sites. These principles are important for the design of future drug‐delivery vehicles capable of ultrasound‐triggered motion. [ABSTRACT FROM AUTHOR]

Background/Objectives: Microparticle-based drug delivery systems offer several advantages for protein-based drug formulations, enhancing patient compliance and therapeutic efficiency through the sustained delivery of the active pharmaceutical ingredient. Over the past few decades, the microfluidics method has emerged as a continuous manufacturing process for preparing drug-encapsulating microparticles, mainly for small molecule drugs. However, comparative assessments for the conventional batch method vs. the microfluidics method for protein-based drug formulations have been lacking. The main objective of this study was to generate immunomodulatory protein drug-loaded injectable formulations using both conventional batch and microfluidics methods. Methods: Therefore, rhCCL22-loaded poly(lactic-co-glycolic) acid (PLGA) microparticles were prepared by conventional homogenization and microfluidics methods. Results: The resulting microparticles were analyzed comparatively, focusing on critical quality attributes such as microparticle size, size distribution, morphology, drug encapsulation efficiency, release kinetics, and batch-to-batch variations in relation to the manufacturing method. Our results demonstrated that the conventional method resulted in microparticles with denser surface porosity and wider size distribution as opposed to microparticles prepared by the microfluidics method, which could contribute to a significant difference in the drug-release kinetics. Additionally, our findings indicated minimal variation within batches for the microparticles prepared by the microfluidics method. Conclusions: Overall, this study highlights the comparative assessment of several critical quality attributes and batch variations associated with the manufacturing methods of protein-loaded microparticles which is crucial for ensuring consistency in efficacy, regulatory compliance, and quality control in the drug formulation manufacturing process. [ABSTRACT FROM AUTHOR]

Background: Ulcerative colitis (UC) increases the risk for venous thromboembolism. Tissue factor (TF) initiates the extrinsic coagulation pathway (ECP). Aims: To investigate the correlation of UC severity with latent ECP activation and TF expression in primary colonic stromal cells (PCSC). Methods: In plasma of 38 UC patients (31 males, disease duration 151 ± 25 months) and 28 healthy controls, exosomes and microparticles (EM) were counted. Moreover, TF protein concentration, activities of EM-bound TF (EM-TFa) and coagulation factor VII (FVIIa) were assessed. In PCSC in culture, TF mRNA (F3) from 12 patients with active UC and 7 controls was evaluated. Results: UC patients had 4– and 3.7– times more exosomes and microparticles, respectively, than controls. TF protein in UC was correlated with several disease severity indices, such as partial Mayo score (pMs; r 0.443), albumin (− 0.362), ESR (0.353), PLT (0.575), and endoscopic Ms (eMs 0.468). EM-TFa was also significantly higher in UC and was correlated to SIBDQ (− 0.64), albumin (− 0.624), disease extent and eMs (0.422). Refractory-to-treatment patients had significantly higher TF protein, EM-TFa and FVIIa. Even within responders, the need for steroids or biologics correlated with a 2.2–times higher EM-TFa. PCSC from active UC maintained higher F3 than controls, which was correlated to pMs (0.56), albumin (− 0.543) and eMs. Treatment with cytokines further upregulated F3. P for all comparisons was < 0.05. Conclusion: Low-grade activation of the ECP associates with clinical, endoscopic UC activity and response to treatment. TF in PCSC mirrors its systemic activity and points to them as a source. [ABSTRACT FROM AUTHOR]

Valorization of agricultural and food by-products (agri-food waste) and maximum utilization of this raw material constitute a highly relevant topic worldwide. Agri-food waste contains different types of phytochemical compounds such as polyphenols, that display a set of biological properties, including anti-inflammatory, chemo-preventive, and immune-stimulating effects. In this work, the microencapsulation of strawberry (Fragaria vesca) plant extract was made by spray-drying using individual biopolymers, as well as binary and ternary blends of pectin, alginate, and carrageenan. The microparticle morphologies depended on the formulation used, and they had an average size between 0.01 μm and 16.3 μm considering a volume size distribution. The encapsulation efficiency ranged between 81 and 100%. The kinetic models of Korsmeyer–Peppas (R2: 0.35–0.94) and Baker–Lonsdale (R2: 0.73–1.0) were fitted to the experimental release profiles. In general, the releases followed a "Fickian Diffusion" mechanism, with total release times varying between 100 and 350 (ternary blends) seconds. The microparticles containing only quercetin (one of the main polyphenols in the plant) showed higher antioxidant power compared to the extract and empty particles. Finally, the addition of the different types of microparticles to the gelatine (2.7 mPa.s) and to the aloe vera gel (640 mPa.s) provoked small changes in the viscosity of the final gelatine (2.3 and 3.3 mPa.s) and of the aloe vera gel (621–653 mPa.s). At a visual level, it is possible to conclude that in the gelatine matrix, there was a slight variation in color, while in the aloe vera gel, no changes were registered. In conclusion, these microparticles present promising characteristics for food, nutraceutical, and cosmetic applications. [ABSTRACT FROM AUTHOR]

Purpose: The study aimed to assess the accumulation levels, spatial distribution, and sources of the potentially toxic elements (PTEs), such as Zn, As, Cd, Pb, Cr, Co, Ni, Cu, Sb, Mo, V, W, Sr, Mn, Bi, Sn, Fe, Cs, Be, and Ba, in urban soils, road dust and their PM10 fractions in Yalta, a seaside resort town of the Crimean Peninsula. Materials and methods: The concentrations of the PTEs were measured in the urban topsoil (0–10 cm), road dust, and their fine particles, < 10 μm in diameter (PM10), using ICP-MS and ICP-AES methods. The soil and road dust samples were collected in 2018 in various functional zones of Yalta and on different types of roads. In total, 69 soil samples and 57 road-dust samples were taken. The PM10 fraction was isolated by sedimentation method according to Stokes' law. Results and discussion: The urban soils and the road dust were contaminated by Pb, Sb, Zn, Sn, Cd, Cu, Bi, Mo, and Mn. The finer particles (PM10) separated from the urban soils and the road dust showed higher accumulation of the PTEs than the bulk samples. The contribution of the PM10 fraction to the total amount of the pollutants in the bulk soil and road-dust samples accounted for 50–80%. The strongest contamination of the urban soils was found in the residential areas, while the road dust was mostly contaminated on the major highways. Conclusion: According to the results of the principal component analysis, most of the pollutants can be attributed to anthropogenic sources − non-exhaust and exhaust vehicle emissions. The other important sources of the PTEs are soil parent materials and the resuspension of soil particles. The contents of PTEs in the bulk soil and road-dust samples correspond to low and medium pollution levels. The elevated levels of the PTEs in the PM10 fraction pose the greatest environmental hazard. [ABSTRACT FROM AUTHOR]

It is urgently demanded to develop biomaterials with balanced hemostatic/antibacterial ability and facile preparation methods. In this work, cationic starch microparticles (MSQP), prepared by the facile grafting of microporous starch particles (MS) with tunable quaternized polyethyleneimine, were readily constructed as promising hemostatic materials for integrated antibacterial and hemostatic performance. The cationic grafts not only endowed MSQP with good antibacterial ability, but also benefited from biocompatible MS to achieve favorable biocompatibility. Moreover, in vitro results confirmed the superior hemostatic property of MSQP2 (with the medium content of cationic grafts) among three MSQP and pristine MS. After investigating the blood-material interactions of MSQP/MS, the procoagulant mechanism of MSQP2 was revealed that the optimal amount of cationic grafts achieves highly balanced plasma-protein adhesion, platelet adhesion and blood coagulation system. In vivo artery-injury model further demonstrated the superior hemostatic performance of MSQP2 for potential severe hemorrhage. This work sheds light on the design of cationic polymer-based biomaterials for balanced antibacterial and hemostatic functions. [ABSTRACT FROM AUTHOR]

BACKGROUND RESULTS CONCLUSION A colorimetric method for the quantification of hydrogen sulfide (H₂S) produced in microbial fermentations was developed using lead gelled alginate microparticles packed in glass columns. The formation of a lead sulfide complex, between H₂S and lead ion (Pb2+) immobilized on the microparticles, allowed simple and accurate quantification by colorimetry.The microparticle‐loaded columns were calibrated and showed significant analytical sensitivity. The calibration curve of the system showed a correlation coefficient (r2) of 0.995 and a detection limit of 1.29 ± 0.02 μg L−1. The application of the columns in laboratory wine fermentations was able to detect variations in H2S production from 10.6 to 23.5 μg L−1 by increasing the sugar content in the medium, and from 10.6 to 3.2 μg L−1 with decreasing nitrogen content in the medium.Validation of the proposed method was carried out by determining H₂S in a vinic fermentation model, the results of which were compared with those obtained using a reference chemical method. The data obtained showed no statistically significant differences between the two methods, confirming the reliability and accuracy of the developed system. © 2024 Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

Purpose: The removal of the residual solvent dichloromethane from biodegradable poly(D,L-lactic-co-glycolic acid) (PLGA) microparticles was investigated by aqueous or alcoholic wet extraction or vacuum-drying. Methods: Microparticles were prepared by the O/W solvent extraction/evaporation method. The solidified microparticles were separated by filtration and the effect of subsequent drying and wet extraction methods were investigated. The residual solvent content was analysed with gas chromatography (organic solvents) and Karl Fischer titration (water). The effect of extraction conditions on microparticle aggregation, surface morphology and encapsulation of the drugs dexamethasone and risperidone was investigated. Results: Residual dichloromethane was reduced to 2.43% (w/w) (20 °C) or 0.03% (w/w) (35 °C) by aqueous wet extraction. With vacuum-drying, residual dichloromethane only decreased from about 5% (w/w) to 4.34% (w/w) (20 °C) or 3.20% (w/w) (35 °C) due to the lack of the plasticizing effect of water. Redispersion of filtered, wet microparticles in alcoholic media significantly improved the extraction due to an increased PLGA plasticization. The potential of different extractants was explained with the Gordon-Taylor equation and Hansen solubility parameters. Extraction in methanol: or ethanol:water mixtures reduced residual dichloromethane from 4 - 7% (w/w) to 0.5 - 2.3% (w/w) within 1 h and 0.08 - 0.18% (w/w) within 6 h. Higher alcohol contents and higher temperature resulted in aggregation of microparticles and lower drug loadings. Conclusion: The final removal of residual dichloromethane was more efficient with alcoholic wet extraction followed by aqueous wet extraction at elevated temperature and vacuum drying of the microparticles. [ABSTRACT FROM AUTHOR]

The traditional catalytic oxidation of carbon monoxide (CO) using metal oxide catalysts often requires either high temperatures (thermocatalysis) or ultraviolet light (UV) excitation (photocatalysis), limiting practical applications under ambient conditions. Our research aimed to develop a catalytic system capable of oxidizing CO to CO2 at room temperature and in the dark. Using the Strong Metal–Support Interaction (SMSI) methodology, several titanium oxide (TiO2)-complexed metals were prepared (Ag, Au, Pd, and Pt). The highest catalytic efficiency of CO oxidation at room temperature was demonstrated for the TiO2-Pt complex. Therefore, this complex was further examined structurally and functionally. Two modes of operation were addressed. The first involved applying the catalytic system to remove CO from an individual's environment (environmental system), while the second involved the installation of the catalysis chamber as a part of a personal protection unit (e.g., a mask). The catalytic activity exhibited a significant reduction in CO levels in both the environmental and personal protection scenarios. The practical application of the system was demonstrated through efficient CO oxidation in air emitted from a controlled fire experiment conducted in collaboration with the Israel Fire and Rescue Authority. [ABSTRACT FROM AUTHOR]

Different reaction control methods for producing nano/microstructures of poly(butyl cyanoacrylate) (PBCA) have been studied, focusing on pH and monomer-to-initiator ratios. However, these methods often require multiple steps and reagents. In the synthesis of PBCA microparticles using three versions of micromixers designed with HH geometry and varying numbers of channels (4, 10, and 15), different synthesis formulations were investigated by varying monomer concentrations. PBCA microparticles synthesized with 19.2% (w/w) n-butyl cyanoacrylate (n-BCA) monomer, a residence time of 0.06 s, a flow rate of 78 mL·min−1, and a phase ratio of 45/55 (W/O), exhibited an average diameter of 642.2 nm as determined by dynamic light scattering (DLS) analysis. In contrast, PBCA microparticles synthesized with 5.0% (w/w) n-BCA monomer, the same residence time of 0.06 s, a flow rate of 39 mL·min−1, and a phase ratio of 20/80 (W/O), exhibited an average diameter of 74.73 µm according to laser diffraction particle size analysis. Polymer formation was confirmed by Fourier-transform infrared (FTIR) spectroscopy in both formulation and process conditions. These results indicate that the parameters for the production of microparticles with different monomer concentrations in the microfluidic system with HH geometry and 15 channels can be optimized for potential applications in cosmetics and pharmaceutical ingredients. [ABSTRACT FROM AUTHOR]

Cannabigerol's (CBG) therapeutic effects are limited by its poor water solubility and low dissolution rate. To improve these properties, supercritical CO2-assisted atomization (SAA) was applied to produce coprecipitates, i.e., CBG nanoparticles coprecipitated in polyvinylpyrrolidone (PVP) microparticles. The experiments were performed by varying the CBG/PVP mass ratio (R) and the overall concentration of solutes CBG+PVP to study the influence of these parameters on particle morphology, particle size, and size distribution. Periodic dynamic light scattering (DLS) analysis was performed at regular time intervals to measure the size of CBG nanoparticles in PVP microparticles. It showed that CBG nanoparticles down to 105 nm were successfully produced through SAA. Dissolution tests were used to verify that a reduction of CBG particle size significantly increased its dissolution rate. In the liquid medium adopted, untreated CBG powder was released in 210 min, whereas CBG nanoparticles of 105 nm were completely dissolved in only 15 min. [ABSTRACT FROM AUTHOR]

Precisely co-delivering antigens and immunosuppressants via nano/microcarriers to antigen-presenting cells (APCs) to induce antigen-specific immune tolerance represents a highly promising strategy for treating or preventing autoimmune diseases. The physicochemical properties of nano/microcarriers play a pivotal role in regulating immune function, with particle size and surface charge emerging as crucial parameters. In particular, very few studies have investigated micron-scale carriers of antigens. Herein, various nanoparticles and microparticles (NPs/MPs) with diverse particle sizes (ranging from 200 nm to 5 μm) and surface charges were prepared. Antigen peptides (MOG35–55) and immunosuppressants were encapsulated in these particles to induce antigen-specific immune tolerance. Two emulsifiers, PVA and PEMA, were employed to confer different surface charges to the NPs/MPs. The in vitro and in vivo studies demonstrated that NP/MP-PEMA could induce immune tolerance earlier than NP/MP-PVA and that NP/MP-PVA could induce immune tolerance more slowly and sustainably, indicating that highly negatively charged particles can induce immune tolerance more rapidly. Among the different sizes and charged particles tested, 200-nm-NP-PVA and 3-μm-MP-PEMA induced the greatest immune tolerance. In addition, the combination of NPs with MPs can further improve the induction of immune tolerance. In particular, combining 200 nm-NP-PVA with 3 μm-MP-PEMA or combining 500 nm-NP-PEMA with 3 μm-MP-PVA had optimal therapeutic efficacy. This study offers a new perspective for treating diseases by combining NPs with MPs and applying different emulsifiers to prepare NPs and MPs. [Display omitted] • A systematic comparison of different sized particles was conducted for designing optimal particle-based treatments for autoimmune diseases. • By comparing different sized nanoparticles and microparticles with different negative surface charges, 200-nm-NP-PVA and 3-μm-MP-PEMA were discovered to be optimal in inducing immune tolerance. • A new perspective for inducing antigen-specific immune tolerance by combining NPs together with specific MPs was proposed. [ABSTRACT FROM AUTHOR]

Metformin is a medication that is commonly prescribed to manage type 2 diabetes. It has been used for more than 60 years and is highly effective in lowering blood glucose levels. Recent studies indicate that metformin may have additional medical benefits beyond treating diabetes, revealing its potential therapeutic uses. Oral medication is commonly used to administer metformin because of its convenience and cost‐effectiveness. However, there are challenges in optimizing its effectiveness. Gastrointestinal side effects and limitations in bioavailability have led to the underutilization of metformin. Innovative drug‐delivery systems such as fast‐dissolving tablets, micro/nanoparticle formulations, hydrogel and microneedles have been explored to optimize metformin therapy. These strategies enhance metformin dosage, targeting, bioavailability and stability, and provide personalized treatment options for improved glucose homeostasis, antiobesity and metabolic health benefits. Developing new delivery systems for metformin shows potential for improving therapeutic outcomes, broadening its applications beyond diabetes management and addressing unmet medical needs in various clinical settings. However, it is important to improve drug‐delivery systems, addressing issues such as complexity, cost, biocompatibility, stability during storage and transportation, loading capacity, required technologies and biomaterials, targeting precision and regulatory approval. Addressing these limitations is crucial for effective, safe and accessible drug delivery in clinical practice. In this review, recent advances in the development and application of metformin‐delivery systems for diabetes and obesity are discussed. [ABSTRACT FROM AUTHOR]

Although tumor cell-derived microparticles (MPs) vaccines have reportedly induced antitumor immune reactions for various cancers, the mechanism by which MPs derived from Hepa1-6 cells are taken up by dendritic cells (DCs) and provide the MPs antigens message to CD8+ T cells to exert their anti-hepatocellular carcinoma (HCC) effects remain unclear. Furthermore, the role of MPs in combination with the small-molecule drug MSI-1436, an inhibitor of protein tyrosine phosphatase 1B (PTP1B), in HCC has not yet been reported. In this study, protein mass spectrometry combined with cytology revealed that MPs are mainly taken up by DCs via the clathrin-mediated endocytosis and phagocytosis pathway and localized mainly in lysosomes. High concentration of tumor necrosis factor-α and interferon-γ was detected in CD8+ T cells stimulated with MPs-loaded DCs. Moreover, MPs combined with MSI-1436 further suppressed the proliferation of HCC cells in C57BL/6 tumor-bearing mice, which was closely correlated with CD4+/CD8+ T cells counts in peripheral blood, spleen, and the tumor microenvironment. Mechanistically, the combination of MPs and MSI-1436 exerts a more powerful anti-HCC effect, which may be related to the further inhibition of the expression of PTP1B. Overall, MPs combined with MSI-1436 exerted stronger antitumor effects than MPs or MSI-1436 alone. Therefore, the combination of MPs and MSI-1436 may be a promising means of treating HCC. [ABSTRACT FROM AUTHOR]

Abstract To detect cellular activities deep within the body using magnetic resonance platforms, magnetosomes are the ideal model of genetically-encoded nanoparticles. These membrane-bound iron biominerals produced by magnetotactic bacteria are highly regulated by approximately 30 genes; however, the number of magnetosome genes that are essential and/or constitute the root structure upon which biominerals form is largely undefined. To examine the possibility that key magnetosome genes may interact in a foreign environment, we expressed mamI and mamL as fluorescent fusion proteins in mammalian cells. Localization and potential protein-protein interaction(s) were investigated using confocal microscopy and fluorescence correlation spectroscopy (FCS). Enhanced green fluorescent protein (EGFP)-MamI and the red fluorescent Tomato-MamL displayed distinct intracellular localization, with net-like and punctate fluorescence, respectively. Remarkably, co-expression revealed co-localization of both fluorescent fusion proteins in the same punctate pattern. An interaction between MamI and MamL was confirmed by co-immunoprecipitation. In addition, changes in EGFP-MamI distribution were accompanied by acquisition of intracellular mobility which all Tomato-MamL structures displayed. Analysis of extracts from these cells by FCS was consistent with an interaction between fluorescent fusion proteins, including an increase in particle radius. Co-localization and interaction of MamI and MamL demonstrate that select magnetosome proteins may associate in mammalian cells.

Abstract Endothelial dysfunction exacerbates hypertension and other vascular complications in diabetes mellitus (DM). Circulating microparticles (MPs) and extracellular vesicles released in patients with DM have emerged as novel regulators of endothelial dysfunction. The obstruction of mineralocorticoid receptors (MRs) is a potential therapeutic approach to reduce cardiovascular complications. Their impact on the obstruction of MRs on circulating MPs and endothelial dysfunction in DM remains unclear. DM was induced in mice through a single intravenous dose of streptozotocin (STZ; 200 mg/kg). Esaxerenone (ESAX; 3 mg/kg/day), a MR blocker was administered via diet for 8 weeks. In this study, the aortas of the DM group showed the endothelial dysfunction and the administration of ESAX ameliorated the endothelial-dependent responses. Moreover, ESAX influences the impaired endothelial-dependent responses of DM-derived MPs. Interestingly, MP levels increased in DM whereas decreased after ESAX administration. In the aorta, the DM-derived MPs increased the expression of intercellular adhesion molecule-1 (ICAM-1). ESAX inhibited the adhesion of DM-derived MPs. Moreover, the ICAM-1 inhibitor A205804 shows similar effects as ESAX. These results indicate that the release and adhesion properties of MPs can be partially obstructed by ESAX via the ICAM-1 signaling pathway, which clarifies the other functions beyond the anti-hypertensive effects of ESAX.

This study presents a mathematical modeling and numerical investigation of oscillatory flow induced microdroplet breakup in low melting point alloy (LMPA)-in-water two-phase flow system in a microchannel. The effects of perturbation flow Weber number, and oscillating frequencies on the droplet breakup dynamics have been elucidated. Lowering the wall temperature will accelerate the solidification process of LMPA droplets, giving rise to the rapid formation of ultra-small particles with size down to 1 micron in less than 3 ms. The versatile approach combines oscillatory flow dominated droplet breakup process and phase change process, leading to the formation of LMPA microparticles with monodispersed size distribution and well-tailored properties by using a straight microchannel, which obviates the need for sophisticated design and complex fabrication process of microdevices. This work will provide a strategy to manipulating LMPA droplet size and structure for the massive production of ultra-small LMPA microparticles via a facile control over the flow conditions in the two-phase flow in a microfluidic system. It will open up for a diversity of applications of LMPA microparticles in various fields such as energy storage and thermal management. [ABSTRACT FROM AUTHOR]

The processes of recharging, heating and evaporation of a positively charged microparticle (MP) introduced into the plasma with an injected high-energy electron beam are considered. It is assumed that the MP is charged outside the plasma and then introduced into the plasma by an accelerating field, where plasma and beam electrons hitting the MP heat and evaporate it. In addition to introducing the MP into the plasma, the positive MP charge provides an additional source of energy needed to heat and evaporate it. Using the OML theory, the system of current and energy balance equations was numerically solved and the conditions, under which the MP is heated to the boiling point of its substance, resulting in its intense evaporation, were determined. The influence of the energy of the electron beam on the process of MP recharging, as well as on the rate of its heating and evaporation, has been studied. An estimate of the particle entry velocity into the plasma has been made; the distances at which its recharging, heating to the boiling point and complete evaporation occur are determined. The work is carried out in order to creating plasma of a given elemental composition.

Abstract Helicobacter pylori infection is involved in gastric diseases such as peptic ulcer and adenocarcinoma. Approved antibiotherapies still fail in 10 to 40% of the infected patients and, in this scenario, targeted nanotherapeutics emerged as powerful allies for H. pylori eradication. Nano/microparticles conjugated with H. pylori binding molecules were developed to eliminate H. pylori by either (i) blocking essential mechanisms of infection, such as adhesion to gastric mucosa or (ii) binding and killing H. pylori through the release of drugs within the bacteria or at the site of infection. Glycan antigens (as Lewis B and sialyl-Lewis X), pectins, lectins, phosphatidylethanolamine and epithelial cell membranes were conjugated with nano/microparticles to successfully block H. pylori adhesion. Urea-coated nanoparticles were used to improve drug delivery inside bacteria through H. pylori UreI channel. Moreover, nanoparticles coated with antibodies against H. pylori and loaded with sono/photosensitizers, were promising for their application as targeted sono/photodynamic therapies. Further, non-specific H. pylori nano/microparticles, but only active in the acidic gastric environment, coated with binders to bacterial membrane, extracellular polymeric substances or to high temperature requirement A protease, were evaluated. In this review, an overview of the existing nanotherapeutics targeting H. pylori will be given and their rational, potential to counteract infection, as well as level of development will be presented and discussed.

Background Acute myocardial infarction (AMI) is one of the common cardiovascular diseases, and despite the widespread use of biomarkers for myocardial necrosis, morbidity and mortality of AMI remain high. Objective To investigate the expression levels and clinical significance of miR-126, mitochondrial components and adhesion molecules in endothelial microparticles (EMPs) . Methods A total of 50 patients with AMI (AMI group), 50 patients with stable coronary artery disease (SCAD) (SCAD group) and 50 healthy subjects (control group) were enrolled in the People's Hospital of Xinjiang Uygur Autonomous Region from September 2021 to September 2022. AMI patients and SCAD patients were hospitalized in our hospital and received percutaneous coronary intervention (PCI), and all healthy subjects were evaluated by the physical examination center of our hospital. Peripheral blood samples and general data of three groups were collected. The morphology of the microparticles (MPs) was observed by transmission electron microscopy (TEM), the level of EMPs was identified by flow cytometry, and the expression of miR-126 in EMPs was detected by fluorescence quantitative PCR. ELISA was used to detect the levels of mitochondrial reactive oxygen species (ROS) and intracellular adhesion molecules [vascular cell adhesion molecule-1 (VCAM-1), intercellular adhesion molecule-1 (ICAM-1), E-selectin, and P-selectin] in EMPs. Results As observed by TEM, the membrane structure of the isolated MPs was intact and its diameter ranged from 100 to 400 nm. Compared with the control group, the expression of miR-126 in plasma EMPs in the AMI group was significantly decreased (P

Lime (Citrus aurantifolia) juice was reported to contain ascorbic acid (AA) and flavonoids, which has bioactivity as antioxidants. To develop an antioxidant product, improving its stability is necessary due to the perishable characteristics of compounds in lime. Therefore, the formulation of polyelectrolyte microparticles using chitosan and alginate was conducted to overcome the weaknesses. This study aims to evaluate the effect of various chitosan, alginate, and lime juice powder (LJP) concentrations on the physical characteristics and antioxidant activity of LJP encapsulated in chitosan-alginate microparticles (CALM). Microparticles with various concentrations of chitosan and alginate were prepared by ionic gelation method using CaCl2 as a crosslinker. The microparticles were evaluated for its physical properties and its antioxidant activity using 2-2-diphenyl-1-picrylhydrazyl reagent. A one-way ANOVA test and Tukey’s honest significant difference post hoc were used to determine the effect of LJP amount on the antioxidant activity. The highest AA content in CALM was 0.14 mg/100 mg, with a % encapsulation efficiency of 18.38% ± 0.02%. Antioxidant activity tests revealed that LJP possessed the strong antioxidant activity with an IC50 value of 32.59 μg/mL, whereas IC50 values of the microparticles ranged from 24.79 ± 0.03 μg/mL to 39.96 ± 0.07 μg/mL. During storage, the IC50 of LJP decreased from 32.59 ± 0.13 μg/mL to 65.53 ± 0.03 μg/mL, whereas the IC50 of microparticles remained stable. This study concluded that the chitosan-alginate polyelectrolyte microparticle formulation can improve and protect LJP’s antioxidant activity.

This investigation developed a novel polyester composite based on the addition of zinc oxide (ZnO) of different sizes. We prepared nine samples Containing different percentages and sizes of ZnO as well as the control sample (Pol-ZnO0). The attenuation factors of Pol-micro ZnO were estimated using Phy-x software, while the HPGe detector and various gamma sources were used to experimentally measure the all-prepared composites. In terms of the two methods for micro composites, good agreement was observed. The linear attenuation coefficient (LAC) of Pol-ZnO20, Pol-ZnO40, and Pol-ZnO60, two more samples one with ZnO nanoparticles instead of microparticles, and the other with half microparticles and half nanoparticles (referenced as 0.5 M + 0.5 N) were determined. For all the Polyester composites and energies, the mixture of microparticles and nanoparticles had greater LAC values than each of the particles on their own. For example, the LAC values for the Pol-ZnO20 polymer at 1.330 MeV are 0.0836, 0.0888, and 0.0903 cm−1 for the microparticles, nanoparticles, and mixture, respectively. The values of the prepared polymer samples' radiation protection efficiency (RPE) against energy with a thickness of 2 cm was determined experimentally. The Pol-ZnO60 0.5 M + 0.5 N sample has the highest RPE out of all the samples, followed by its nanoparticle counterpart, and then its microparticle counterpart. On the other hand, the Pol-ZnO0 sample, the polymer with no ZnO content, at all energies has the lowest RPE, followed by the three Pol-ZnO20 samples.

Introduction: Plastics carried in the outflow of major rivers can be made available and subsequently ingested by marine fishes, causing lethal and sublethal effects. Highly abundant, vertically migrating myctophids play a crucial role in facilitating nutrient cycling between the epi- and mesopelagic zones. However, this diel movement may also make myctophids significant conduits for transporting ingested microparticles from surface waters to deeper food webs. Methods: We examined the gastrointestinal tracts of 340 myctophids caught at varying distances from the Columbia River mouth in the epipelagic zone of the northeast Pacific Ocean to determine if proximity to a presumed point source influences microparticle ingestion. Results: While we found no direct spatial connection with ingestion frequency, we discovered that (a) ~34% of myctophids had either synthetic or other anthropogenic particles retained in their GI tract, (b) microparticle ingestion was higher in an active-feeding species of myctophid (Tarletonbeania crenularis) than an inactive-feeding species (Stenobrachius leucopsarus), and (c) species and standard length were the most influential predictors of microparticle consumption in our best fit model. Discussion: Our failure to detect a significant relationship between distance from a source and ingestion by myctophids is likely due to the particles undergoing fluctuations in dispersal patterns once they enter the ocean, particularly for microfibers which can be transported across large distances. Biological factors like body size may be more relevant to understanding microparticle ingestion patterns in mesopelagic fishes. Overall, our study highlights the potential role myctophids serve as multidirectional transporters of microparticles in Northern California Current food webs, with potential impacts on fisheries and human food systems. [ABSTRACT FROM AUTHOR]

In this study, novel iron-based spiky microparticles (approximately 1–2μm in diameter) were synthesized using iron oxalate precursors using a straightforward one-step hydrothermal reaction. The microparticles’ morphological, mineralogical and chemical properties were investigated using scanning electron microscopy (SEM), X-ray diffractometry (XRD), Raman spectroscopy and UV-Vis spectroscopy. The physico-chemical characteristics of spiky microparticles were also compared with cubic iron microparticles synthesized using standalone iron as well as with the addition of glycine. XRD and Raman analyses identified substantial presence of humboldtine, a type of ferrous oxalate dehydrate mineral, in the resultant yellowish solid hydrothermal product. The mechanism involving reactions of species in the hydrothermal process was described herein. The results described in this study afford vital insights into the design of iron oxalate-based microparticles synthesis processes. [ABSTRACT FROM AUTHOR]

Helicobacter pylori infection is involved in gastric diseases such as peptic ulcer and adenocarcinoma. Approved antibiotherapies still fail in 10 to 40% of the infected patients and, in this scenario, targeted nanotherapeutics emerged as powerful allies for H. pylori eradication. Nano/microparticles conjugated with H. pylori binding molecules were developed to eliminate H. pylori by either (i) blocking essential mechanisms of infection, such as adhesion to gastric mucosa or (ii) binding and killing H. pylori through the release of drugs within the bacteria or at the site of infection. Glycan antigens (as Lewis B and sialyl-Lewis X), pectins, lectins, phosphatidylethanolamine and epithelial cell membranes were conjugated with nano/microparticles to successfully block H. pylori adhesion. Urea-coated nanoparticles were used to improve drug delivery inside bacteria through H. pylori UreI channel. Moreover, nanoparticles coated with antibodies against H. pylori and loaded with sono/photosensitizers, were promising for their application as targeted sono/photodynamic therapies. Further, non-specific H. pylori nano/microparticles, but only active in the acidic gastric environment, coated with binders to bacterial membrane, extracellular polymeric substances or to high temperature requirement A protease, were evaluated. In this review, an overview of the existing nanotherapeutics targeting H. pylori will be given and their rational, potential to counteract infection, as well as level of development will be presented and discussed. [ABSTRACT FROM AUTHOR]

Periodontitis is a common chronic inflammatory disease primarily caused by the prevalence of bacterial overgrowth resulting in the development of an inflammatory condition that destroys the tooth's supporting tissues and eventual tooth loss. Comparatively, to other treatment methods, it is difficult for topical antibacterial drugs to effectively permeate the biofilm's physical barrier, making conventional therapy for periodontitis more challenging. This novel study combines thermosensitive in situ hydrogel with microparticles (MPs) to enhance the targeted delivery of metronidazole (MET) to the periodontal pocket. Polycaprolactone (PCL) polymer was utilized to produce bacteria-sensitive MPs. Additionally, the study assessed the attributes of MPs and demonstrated an enhancement in the in vitro antibacterial efficacy of MPs towards Staphylococcus aureus (SA) and Escherichia coli (EC). Subsequently, we incorporated MET-MPs into thermosensitive in situ hydrogel formulations using chitosan. The optimized formulations exhibited stability, appropriate gelation temperature, mucoadhesive strength, and viscosity. In vitro permeation tests showed selective and prolonged drug release against SA and EC. Ex vivo experiments demonstrated no significant differences between in situ hydrogel containing pure MET and MET–MPs in biofilm quantity, bacterial counts, and metabolic activity in biofilms. According to in vitro tests and the effectiveness of the antibacterial activity, this study has exhibited a novel methodology for more efficacious therapies for periodontitis. This study aims to utilize MET in MPs to improve its effectiveness, enhance its antibacterial activity, and improve patient treatment outcomes. In further research, the efficacy of the treatment should be investigated in vivo using an appropriate animal model. [ABSTRACT FROM AUTHOR]

Melanoma is one of the most aggressive forms of skin cancer, which is characterized by metastasis and poor prognosis due to the limited effectiveness of current therapies and the toxicity of conventional drugs. For this reason and in recent years, one of the most promising strategies in the treatment of this form of cancer is the use of drug delivery systems as carriers capable of conveying the therapeutic agent into the tumor microenvironment, thus preventing its degradation and improving its safety and effectiveness profiles. In the present work, microparticles based on silk fibroin and epifibroin 0039, silk-derived proteins loaded with idebenone, were created, which act as therapeutic carriers for topical use in the treatment of melanoma. The resulting particles have a spherical shape, good loading efficiency, and release capacity of idebenone. Efficacy studies have demonstrated a reduction in the proliferation of COLO-38, melanoma tumor cells, while safety tests have demonstrated that the microparticles are not cytotoxic and do not possess prosensitizing activity. Notably, transdermal release studies revealed that all particles released idebenone over more days. The analysis of the stimulatory markers of the proinflammatory process, CD54 and CD86, did not show any increase in expression, thus confirming the absence of potential prosesensitization effects of the silk fibroin-based particles. The research, therefore, found that idebenone-loaded silk protein microparticles could effectively reduce the proliferation of melanoma cells without cytotoxicity. This indicates the promise of a safe and effective treatment of melanoma. [ABSTRACT FROM AUTHOR]

The scientific field of microcarrier systems has gained significant advancements, especially in drug delivery and controlled release mechanisms. This manuscript provides a comprehensive overview of the progress in developing pectin-derived microcarriers fabricated using microfluidic technology. Pectin, a naturally occurring polysaccharide, has garnered attention due to its biocompatibility, biodegradability, and ability to form hydrogels, making it an ideal candidate for forming microcarriers. The integration of microfluidic technology in synthesizing these carriers has revolutionized their design and functionality, enabling precise control over size, morphology, and encapsulation efficiency. This review systematically analyzes the methodologies employed in the microfluidic fabrication of pectin-based microparticles, highlighting the significant advantages this technology offers, such as reduced use of solvents, enhanced reproducibility, and scalability. [ABSTRACT FROM AUTHOR]

To improve the therapeutic activity of inhaled glucocorticoids and reduce potential side effects, we designed a formulation combining the advantages of nanoparticles, which have an enhanced uptake by alveolar cells, allow targeted delivery and sustained drug release, as well as limited drug systemic passage, with those of microparticles, which display good alveolar deposition. Herein, a polymer-drug conjugate, poly(malic acid)-budesonide (PMAB), was first synthesized with either 11, 20, 33, or 43 mol% budesonide (drug:polymer from 1:8 to 3:4), the drug creating hydrophobic domains. The obtained conjugates self-assemble into nanoconjugates in water, yielding excellent drug loading of up to 73 wt%, with 80–100 nm diameters. In vitro assays showed that budesonide could be steadily released from the nanoconjugates, and the anti-inflammatory activity was preserved, as evidenced by reduced cytokine production in LPS-activated RAW 264.7 macrophages. Nanoconjugates were then embedded into microparticles through spray-drying with L-leucine, forming nano-embedded microparticles (NEMs). NEMs were produced with an aerodynamic diameter close to 1 µm and a density below 0.1 g.cm−3, indicative of a high alveolar deposition. NEMs spray-dried with the less hydrophobic nanoconjugates, PMAB 1:4, were readily dissolved in simulated lung fluid and were chosen for in vivo experiments to study pharmacokinetics in healthy rats. As it was released in vivo from NEMs, sustained distribution of budesonide was obtained for 48 h in lung tissue, cells, and lining fluid. With high loading rates, modulable release kinetics, and low cytotoxicity, these nanoconjugates delivered by NEMs are promising for the more efficient treatment of pulmonary inflammatory diseases. [ABSTRACT FROM AUTHOR]

Polyvinylpyrrolidone (PVP) exhibits remarkable qualities; owing to the strong affinity for water of its pyrrolidone group, which enhances compatibility with aqueous systems, it is effective for stabilizing, binding, or carrying food, drugs, and cosmetics. However, coating the surface of polymeric films with PVP is not practical, as the coatings dissolve easily in water and ethanol. Poly(silane–pyrrolidone) nano/microparticles were prepared by combining addition polymerization of methacryloxypropyltriethoxysilane and N-vinylpyrrolidone, followed by step-growth Stöber polymerization of the formed silane–pyrrolidone monomer. The silane–pyrrolidone monomeric solution was spread on oxidized polyethylene films with a Mayer rod and polymerized to form siloxane (Si-O-Si) self-cross-linked durable anti-fog thin coatings with pyrrolidone groups exposed on the outer surface. The coatings exhibited similar wetting properties to PVP with significantly greater stability. The particles and coatings were characterized by microscopy, contact angle measurements, and spectroscopy, and tested using hot fog. Excellent anti-fogging activity was found. [ABSTRACT FROM AUTHOR]

Plastics are present in almost every aspect of our lives. Polyethylene terephthalate (PET) is commonly used in the food industry. Microparticles can contaminate food and drinks, posing a threat to consumers. The presented study aims to determine the effect of microparticles of PET on the population of neurons positive for selected neurotransmitters in the enteric nervous system of the jejunum and histological structure. An amount of 15 pigs were divided into three groups (control, receiving 0.1 g, and 1 g/day/animal orally). After 28 days, fragments of the jejunum were collected for immunofluorescence and histological examination. The obtained results show that histological changes (injury of the apical parts of the villi, accumulations of cellular debris and mucus, eosinophil infiltration, and hyperaemia) were more pronounced in pigs receiving a higher dose of microparticles. The effect on neuronal nitric oxide synthase-, and substance P-positive neurons, depends on the examined plexus and the dose of microparticles. An increase in the percentage of galanin-positive neurons and a decrease in cocaine and amphetamine-regulated transcript-, vesicular acetylcholine transporter-, and vasoactive intestinal peptide-positive neurons do not show such relationships. The present study shows that microparticles can potentially have neurotoxic and pro-inflammatory effects, but there is a need for further research to determine the mechanism of this process and possible further effects. [ABSTRACT FROM AUTHOR]

The processes of recharging, heating and evaporation of a positively charged microparticle (MP) introduced into the plasma with an injected high-energy electron beam are considered. It is assumed that the MP is charged outside the plasma and then introduced into the plasma by an accelerating field, where plasma and beam electrons hitting the MP heat and evaporate it. In addition to introducing the MP into the plasma, the positive MP charge provides an additional source of energy needed to heat and evaporate it. Using the OML theory, the system of current and energy balance equations was numerically solved and the conditions, under which the MP is heated to the boiling point of its substance, resulting in its intense evaporation, were determined. The influence of the energy of the electron beam on the process of MP recharging, as well as on the rate of its heating and evaporation, has been studied. An estimate of the particle entry velocity into the plasma has been made; the distances at which its recharging, heating to the boiling point and complete evaporation occur are determined. The work is carried out in order to creating plasma of a given elemental composition. [ABSTRACT FROM AUTHOR]

Microparticles (MPs) are secreted by all cells, where they play a key role in intercellular communication, differentiation, inflammation, and cell energy transfer. P2X7 receptor (P2X7R) activation by extracellular ATP (eATP) causes a large MP release and affects their contents in a cell-specific fashion. We investigated MP release and functional impact in microglial cells from P2X7R-WT or P2X7R-KO mice, as well as mouse microglial cell lines characterized for high (N13-P2X7RHigh) or low (N13-P2X7RLow) P2X7R expression. P2X7R stimulation promoted release of a mixed MP population enriched with naked mitochondria. Released mitochondria were taken up and incorporated into the mitochondrial network of the recipient cells in a P2X7R-dependent fashion. NLRP3 and the P2X7R itself were also delivered to the recipient cells. Microparticle transfer increased the energy level of the recipient cells and conferred a pro-inflammatory phenotype. These data show that the P2X7R is a master regulator of intercellular organelle and MP trafficking in immune cells. Graphical Abstract [ABSTRACT FROM AUTHOR]

Purpose: When operating near cranial motor nerves, transient postoperative weakness of target muscles lasting weeks to months is often observed. As nerves are typically intact at a procedure's completion, paresis is hypothesized to result from a combination of neurapraxia and axonotmesis. As both neurapraxia and axonotmesis involve Schwann cell injury and require remyelination, we developed an in vitro RSC96 Schwann cell model of injury using hydrogen peroxide (H2O2) to induce oxidative stress and investigated the efficacy of candidate therapeutic agents to promote RSC96 viability. As a first step in developing a long-term local administration strategy, the most promising of these agents was incorporated into sustained-release microparticles and investigated for bioactivity using this assay. Methods: The concentration of H2O2 which reduced viability by 50% was determined to establish a standard for inducing oxidative stress in RSC96 cultures. Fresh cultures were then co-dosed with H2O2 and the potential therapeutics melatonin, N-acetylcysteine, resveratrol, and 4-aminopyridine. Schwann cell viability was evaluated and the most efficacious agent, N-acetylcysteine, was encapsulated into microparticles. Eluted samples of N-acetylcysteine from microparticles was evaluated for retained bioactivity. Results: 100 µM N-acetylcysteine improved the viability of Schwann cells dosed with H2O2. 100 µM Microparticle-eluted N-acetylcysteine also enhanced Schwann cell viability. Conclusion: We developed a Schwann cell culture model of iatrogenic nerve injury and used this to identify N-acetylcysteine as an agent to promote recovery. N-acetylcysteine was packaged into microparticles and demonstrated promise as a locally administrable agent to reduce oxidative stress in Schwann cells. [ABSTRACT FROM AUTHOR]

5-Fluorouracil (5-FU) is a chemotherapeutic agent used in therapies for both systematically and topical treatment of different types of cancers. Depending on the period of application, its administration may lead to different side effects such as nausea, headache, pain or even photosensitivity. To avoid them, the drug may be encapsulated into polymeric particles. In the present study, bio polymeric spheres based on chitosan, a linear polysaccharide, are presented. The spheres are formulated by an emulsion technique with solvent evaporation. Three types of particles are synthesized: without crosslinker, with sodium tripolyphosphate and glutaraldehyde crosslinker. The resultant structures are evaluated regarding their size, morphology, and encapsulation efficiency. The crosslinking process and the drug presence in the particles is confirmed by FT-IR. A drug release study is conducted to examine the release kinetics and understand the release behaviour depending on the presence and the type of the crosslinker. [ABSTRACT FROM AUTHOR]

Microneedles (MNs) are micron-sized needles, typically <2 mm in length, arranged either as an array or as single needle. These MNs offer a minimally invasive approach to ocular drug delivery due to their micron size (reducing tissue damage compared to that of hypodermic needles) and overcoming significant barriers in drug administration. While various types of MNs have been extensively researched, significant progress has been made in the use of hollow MNs (HMNs) for ocular drug delivery, specifically through suprachoroidal injections. The suprachoroidal space, situated between the sclera and choroid, has been targeted using optical coherence tomography-guided injections of HMNs for the treatment of uveitis. Unlike other MNs, HMNs can deliver larger volumes of formulations to the eye. This review primarily focuses on the use of HMNs in ocular drug delivery and explores their ocular anatomy and the distribution of formulations following potential HMN administration routes. Additionally, this review focuses on the influence of formulation characteristics (e.g., solution viscosity, particle size), HMN properties (e.g., bore or lumen diameter, MN length), and routes of administration (e.g., periocular transscleral, suprachoroidal, intravitreal) on the ocular distribution of drugs. Overall, this paper highlights the distinctive properties of HMNs, which make them a promising technology for improving drug delivery efficiency, precision, and patient outcomes in the treatment of ocular diseases. [Display omitted] [ABSTRACT FROM AUTHOR]

The aim of the work. Terazosin HCL, which is a selective alpha-1 antagonist, has been recommended for the treatment of benign prostatic hyperplasia-related medical conditions, including hypertension and urinary tract disorders. The purpose of this research was to create microparticles that would have a prolonged release of terazosin hydrochloride (TZ). However, TZ is a medicine that is readily soluble and has a high capability of dissolving in water. Materials and methods. A validated HPLC method was established to assess TZ. The TZ microparticles were produced using the process of melt dispersion by utilising cetyl palmitate (CP), myristic acid (MA), Glycerol monostearate 4055 (type II) or Kolliwax® GMS II (GMS), polyethylene glycol 400 (PEG 400) as a plasticizer, and tween 80 as a stabilizing agent. Different formulations of TZ microparticles were evaluated with regard to particle size, zeta potential, and release, and morphological scanning was performed. Results. A zeta potential that falls between -22.9 and -29.4 mV is possessed by TZ microparticles. Furthermore, the size of TZ microparticles falls between 2.11 and 5.60 μm, and the polydispersity index (PDI) was between 0.24 to 0.41. In addition, the formula (F4) that included CP, GMS, PEG 400, and Tween 80 in the proportions of 0.8:0.2:1:0.5 had the highest zeta potential (ZP) and dissolved more than 85 % of TZ after 8 hours. Therefore, F4 was chosen for the purpose of conducting morphological research. Conclusion. Employing the use of CP, GMS, PEG 400, and Tween 80 in a ratio of 0.8:0.2:1:0.5 could result in the generation of microparticles of TZ that are the most acceptable. [ABSTRACT FROM AUTHOR]

The space environment is extremely hostile to the spacecraft but also to the equipment it carries. The materials which are used to the external side of the spacecraft, the solar panels, the sensors, and the electronics circuits, suffer greatly from their exposure to it. Extreme temperatures, ultraviolet radiation, ionizing radiation from solar proton events and cosmic rays, atomic oxygen in LEO, as well as collisions with micrometeoroids and space debris are factors that degrade the stuff, multiply the mission cost, and increase the risk. Therefore, the state-of-art of material technology is needed. In this study, a set of materials and technologies are presented, which reduce the above-mentioned risks. Extreme temperatures, ultra-vacuum, atomic oxygen, and high-energy radiation including particles as well as energy sources (X- and gamma rays) are potential extreme exposure conditions. Testing and qualification of materials exposed to these extreme conditions is a difficult task, to enable the design and manufacturing of high-endurance reliable components to be used in the world's most sophisticated satellite and spacecraft components, as well as in future endeavors into the vicinity of the Solar System. [ABSTRACT FROM AUTHOR]

We hypothesized that early intra-central nervous system (CNS) responses in a murine model of decompression sickness (DCS) would be reflected by changes in the microparticles (MPs) that exit the brain via the glymphatic system, and due to systemic responses the MPs would cause inflammatory changes lasting for many days leading to functional neurological deficits. Elevations on the order of threefold of blood-borne inflammatory MPs, neutrophil activation, glymphatic flow, and neuroinflammation in cerebral cortex and hippocampus were found in mice at 12 days after exposure to 760 kPa of air for 2 h. Mice also exhibited a significant decline in memory and locomotor activity, as assessed by novel object recognition and rotarod testing. Similar inflammatory changes in blood, neuroinflammation, and functional impairments were initiated in naïve mice by injection of filamentous (F-) actin-positive MPs, but not F-actin-negative MPs, obtained from decompressed mice. We conclude that high pressure/decompression stress establishes a systemic inflammatory process that results in prolonged neuroinflammation and functional impairments in the mouse decompression model. NEW & NOTEWORTHY: Elevated glymphatic flow due to astrocyte and microglial activation from high-pressure exposure triggers release of microparticles (MPs) to the circulation where neutrophil activation and production of filamentous (F)-actin expressing MPs result in a persistent feed-forward neuroinflammatory cycle and functional deficits lasting for at least 12 days. [ABSTRACT FROM AUTHOR]

Over the years, research regarding the Zika virus has been steadily increasing. Early immunization for ZIKV is a priority for preventing complications such as microencephaly and Guillain–Barré syndrome (GBS). Unlike traditional vaccination approaches, oral dissolving films (ODFs) or mucoadhesive film technology is an emerging, exciting concept that can be used in the field of pharmaceuticals for vaccine design and formulation development. This attractive and novel method can help patients who suffer from dysphagia as a complication of a disease or syndrome. In this study, we investigated a microparticulate Zika vaccine administered via the buccal route with the help of thin films or oral dissolving films (ODFs) with a prime dose and two booster doses two weeks apart. In vitro, the ODFs displayed excellent physiochemical properties, indicating that the films were good carriers for vaccine microparticles and biocompatible with the buccal mucosa. In vivo results revealed robust humoral (IgG, subtypes IgG1 and IgG2a) and T-cell responses (CD4+/CD8+) for ZIKV-specific immunity. Both the Zika MP vaccine and the adjuvanted Zika MP vaccine affected memory (CD45R/CD27) and intracellular cytokine (TNF-α and IL-6) expression. In this study, ZIKV vaccination via the buccal route with the aid of ODFs demonstrated great promise for the development of pain-free vaccines for infectious diseases. [ABSTRACT FROM AUTHOR]