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Non-invasive neuromodulation assisted by exogenous stimuli-responsive nanoplatforms for Alzheimer’s disease and Parkinson's disease therapy
No full textIn recent decades, the incidence of neurodegenerative diseases such as Alzheimer’s disease (AD) and Parkinson’s disease (PD) has risen continuously, significantly impairing patients’ quality of life while imposing growing economic and social burdens. Traditional treatments exhibit limited effectiveness in halting disease progression. Non-invasive neuromodulation techniques, utilizing electromagnetic fields, light, or ultrasound, have emerged as promising strategies to modulate neural activity and alleviate symptoms. However, achieving spatially precise and targeted neuromodulation remains challenging. The integration of stimuli-responsive nanoplatforms addresses this limitation. These nanoplatforms, engineered to respond to specific stimuli, can deliver therapeutic agents to the desired brain regions. By enabling controlled and localized drug release, they facilitate precise neuromodulation. Despite their potential, several hurdles must be overcome, including the optimization of nanoplatform design, elucidating complex nanoplatform-brain interactions, and ensuring long-term safety and efficacy. Nonetheless, combining non-invasive neuromodulation with stimuli-responsive nanoplatforms holds revolutionary potential for neurodegenerative disease therapy, offering targeted, personalized treatments that may halt or slow disease progression. This comprehensive review explores the therapeutic potential and applications of non-invasive neuromodulation assisted by exogenous stimuli-responsive nanoplatforms for AD and PD therapy
Effect of Aluminium Addition on Mechanical and Corrosion Characteristics of Sterling Silver AgCuZnSi Alloy
No full textThis study investigates the effects of aluminum addition on the mechanical and corrosion properties of a sterling silver alloy in the Ag-Cu-Zn-Si system. Corrosion behavior was evaluated using potentiodynamic polarization tests, open-circuit potential measurements, and the linear polarization resistance method. The alloys were tested in four different solutions: artificial sweat, 0.9% NaCl, and 0.1M and 0.01M Na₂S solutions. Mechanical properties were assessed through Brinell hardness testing. The results indicate that aluminum improves the corrosion resistance of the alloy, but only up to a certain concentration. A small aluminum addition enhances corrosion resistance compared to the reference alloy, while a further increase reduces it. The best performance was observed for the AgCu1.9Zn3.7Al1.6Si0.3 alloy
Optimizing Ex Vivo Joint Models: Investigating Glucose and Oxygen Levels for Enhanced Tissue Maintenance
No full textThere are several challenges in using ex vivo and in vitro culture
models in cartilage research. First, monocultures of chondrocytes or
cartilage tissue fail to capture the complexity of the joint, where cartilage cells interact with cells from the synovium and subchondral
bone. Second, there is significant variability in the glucose and oxygen levels used across different studies, with no standardized protocol for employing high-glucose (HG) or low-glucose (LG) DMEM,
the two most commonly used culture media. This lack of standardization could affect the reproducibility of results and hinder clinical
translation in subsequent phases. The aim of the present study is to
develop an ex vivo co-culture system using osteochondral and synovium tissue and to investigate the impact of different levels of glucose in the establishment of an ex vivo joint model under different
oxygen conditions.Abstracts TERMIS EU Congress Freiburg, Germany May 20–23, 202
Uticaj tartarata na taloženje-rastvaranje cinka za primenu u baterijama na bazi vodenih rastvora
No full textZinc-ion batteries (ZIBs) have recently gained significant attention as a sustainable energy storage
solution due to their cost-effectiveness and safety. Despite offering high theoretical capacity and
low redox potential, ZIBs face challenges such as dendrite growth and low zinc utilization rates,
which hinder their performance. The objective of this study was to optimize the electrolyte
composition to enhance the performance of a zinc electrode electrochemically deposited on a
copper substrate within the zinc(II)–NH4Cl system. The influence of Zn2+ and NH4
+
ion
concentrations, current density, and the addition of sodium tartrate on the morphology and
behavior of the anode material during charge and discharge cycles was examined. Results
demonstrated that the addition of sodium tartrate significantly improves the electrochemical
performance of the anode material and reduces corrosion in the electrolyte. The findings from this
study suggest that electrolyte engineering could potentially provide a solution for better
performance and extended longevity of ZIBsCink-jonske baterije (ZIB) su nedavno dobile značajnu pažnju kao održivo rešenje za skladištenje
energije zbog svoje isplativosti i sigurnosti. Uprkos tome što nude visok teoretski kapacitet i nizak
redoks potencijal, ZIB se suočavaju sa izazovima kao što su rast dendrita i niske stope
iskorišćenja cinka, što ometa njihov učinak. Cilj ove studije je bio da se optimizuje sastav
elektrolita kako bi se poboljšale performanse cink elektrode elektrohemijski deponovane na
bakarnoj podlozi u sistemu cink(II)–NH4Cl. Ispitivan je uticaj koncentracija jona Zn2+ i NH4
+
,
gustine struje i dodatka natrijum-tartarata na morfologiju i ponašanje anodnog materijala tokom
ciklusa punjenja i pražnjenja. Rezultati su pokazali da dodatak natrijum tartarata značajno
poboljšava elektrohemijske performanse anodnog materijala i smanjuje koroziju u elektrolitu.
Nalazi ove studije sugerišu da bi inženjering elektrolita potencijalno mogao da pruži rešenje za
bolje performanse i produženi vek ZIB-a
Incorporation of Pork Meat and Blood Plasma Proteins into a Cocoa Cream Matrix: Characterization, Comparison of Functional Properties, and In Vitro Simulated Digestion
No full textConsumer requirements for confectionery products have changed significantly over the past decade. These changes are evident in the growing demand for products that are high in protein but lower in energy content and, as a result, the market for these types of products is expanding. This study compared the chemical composition and functional properties of pork meat protein (MP) and blood plasma protein (BP) and evaluated their incorporation into cocoa cream formulations. Functional properties, such as water-holding capacity (WHC) and oil-holding capacity (OHC), were determined. Essential amino acid profiles were determined using HPLC analysis, and protein digestibility was evaluated both in the native form and after incorporation into the cocoa cream matrix via in vitro enzymatic digestion assays. Additionally, antioxidant activity of the enriched cocoa creams was assessed using the established ABTS assay. Results showed that BP contained a higher proportion of essential amino acids (26.44% of total amino acids), meeting the FAO/WHO recommendations, and exhibited superior digestibility compared to MP. Both proteins demonstrated high WHC and OHC values. The antioxidant potential of BP-enriched cocoa cream further supported its functional benefits. These findings indicate that blood plasma protein is a promising ingredient for enhancing the nutritional and functional quality of cocoa cream products
Natural deep eutectic solvents for efficient mild pretreatment of crop residues
No full textCrop residues consist predominantly of lignin, cellulose, and hemicellulose, organized together as lignocellulose. With approximately 200 billion tons produced per year, lignocellulosic biomass is the most abundant source of plant-based raw materials available in nature [1]. Burning crop residues worldwide emits around 70,000 kt of CO2eq in total [2] and this can be prevented by implementing these residues in biorefinery. The prerequisite step to utilize these residues is to pretreat them and break down the complex lignocellulose structure. Natural deep eutectic solvents (NADES) are emerging as a green, biocompatible, biodegradable, and cheaper alternative to ionic liquids that are widely used as a highly efficient pretreatment. Their physicochemical properties can be fine-tuned by altering the number, type, and molar ratio of NADES constituents. Acidic NADES composed of choline chloride and carboxylic acids proved to be suitable for lignocellulosic biomass delignification. However, to increase the pretreatment’s efficiency, elevated temperatures and prolonged pretreatment duration are needed. This study aimed to test the possibility of subjecting corn stalks to NADES pretreatment at room temperature and in short time intervals to improve the sustainability of the pretreatment. Experimental: Taguchi orthogonal array design (L9) was used to select the best pretreatment conditions for achieving the highest delignification rate. Key parameters of the process, namely choline chloride to lactic acid ratio in NADES, water addition, and pretreatment duration, were optimized through nine experimental runs. Biomass was pretreated at room temperature while being stirred constantly. After pretreatment, biomass was recovered, analyzed for residual lignin content, and subsequently subjected to enzymatic hydrolysis using commercial Cellic CTec2 mixture to estimate the pretreatment’s efficiency in terms of improving both biomass delignification and digestibility. Results: The optimal conditions for achieving the highest delignification rate were defined based on the results obtained, as follows: choline chloride-tolactic acid ratio 1:5, addition of 20% water, and 10-minute-long pretreatment performed at room temperature. Analysis of variance confirmed that the composition of NADES contributed mostly to the pretreatment’s efficiency. Sugar yields obtained after 48-hour-long enzymatic hydrolysis were mostly correlated to the biomass delignification. This suggests that corn stalks could be successfully delignified and further used through various fermentation processes with reduced energy demands. However, different types of NADES could be tested to make this pretreatment energy-efficient and cost-effective on a larger scale. Moreover, the reusability of NADES and the potential valorization of extracted lignin should also be examined to shift this pretreatment toward a zero-waste approach
Liposome-Based Encapsulation of Extract from Wild Thyme (Thymus serpyllum L.) Tea Processing Residues for Delivery of Polyphenols
No full textThis study developed phospholipid-based liposomes loaded with extract from wild thyme (Thymus serpyllum L.) tea processing residues to enhance polyphenol stability and delivery. Liposomes were prepared with phospholipids alone or combined with 10–30 mol% cholesterol or β-sitosterol. The effect of different lipid compositions on encapsulation efficiency (EE), particle size, polydispersity index (PDI), zeta potential, stability, thermal properties, diffusion coefficient, and diffusion resistance of the liposomes was investigated. Liposomes with 10 mol% sterols (either cholesterol or β-sitosterol) exhibited the highest EE of polyphenols, while increasing sterol content to 30 mol% resulted in decreased EE. Particle size and PDI increased with sterol content, while liposomes prepared without sterols showed the smallest vesicle size. Encapsulation of the extract led to smaller liposomal diameters and slight increases in PDI values. Zeta potential measurements revealed that sterol incorporation enhanced the surface charge and stability of liposomes, with β-sitosterol showing the most pronounced effect. Stability testing demonstrated minimal changes in size, PDI, and zeta potential during storage. UV irradiation and lyophilization processes did not cause significant polyphenol leakage, although lyophilization slightly increased particle size and PDI. Differential scanning calorimetry revealed that polyphenols and sterols modified the lipid membrane transitions, indicating interactions between extract components and the liposomal bilayer. FT-IR spectra confirmed successful integration of the extract into the liposomes, while UV exposure did not significantly alter the spectral features. Thiobarbituric acid reactive substances (TBARS) assay demonstrated the extract’s efficacy in mitigating lipid peroxidation under UV-induced oxidative stress. In contrast, liposomes enriched with sterols showed enhanced peroxidation. Polyphenol diffusion studies showed that encapsulation significantly delayed release, particularly in sterol-containing liposomes. Release assays in simulated gastric and intestinal fluids confirmed controlled, pH-dependent polyphenol delivery, with slightly better retention in β-sitosterol-enriched systems. These findings support the use of β-sitosterol- and cholesterol-enriched liposomes as stable carriers for polyphenolic compounds from wild thyme extract, as bioactive antioxidants, for food and nutraceutical applications
A simple alginate-based 3D in vitro model for preclinical anticancer drug evaluation
No full textThe development of novel anticancer drugs is a slow and costly process, with only 5 out of 5,000 compounds ultimately reaching the market. A major limitation lies in the low predictability of traditional preclinical methods, such as two-dimensional (2D) cell cultures and animal experiments, which often fail to replicate the cellular responses to drugs observed in patients. Therefore, three-dimensional (3D) in vitro models have emerged as valuable tools for drug screening. The aim of this study was to establish a 3D in vitro model based on alginate microfibers suitable for immobilizing various cancer cell types for anticancer drug testing. Murine osteosarcoma cells K7M2-wt (cell density: 4×106 cells cm-3) were immobilized in 2 wt.% Ca-alginate microfibers (diameter: 500−600 µm) with or without 2 wt.% hydroxyapatite (HAP) particles, while human non-small cell lung carcinoma cells NCI-H460 (cell density: 4×106 cells cm-3) were immobilized in 2 wt.% Ba-alginate microfibers (diameter ~ 550 µm) by manual extrusion. During long-term cultivation, cells in microfibers stayed viable and metabolically active, forming aggregates over time. Anticancer drug testing revealed that the half-maximal inhibitory concentration (IC50) values for 3D cultures of both K7M2-wt and NCI-H460 cells were up to 50-fold higher compared to those for 2D cultures. Additionally, the gene expression analysis showed a significant upregulation of drug resistance–related genes in 3D cultures. Overall, the obtained results align with the observed higher resistance to anticancer drugs in patients compared to traditional preclinical models, highlighting the potential of the proposed model to improve in vitro drug screening reliability
Bio-catalytic preparation of poly(methacrylic acid) hydrogels using peroxidase from potato peel waste and preliminary evaluation of their anti-inflammatory potential
No full textA new eco-friendly initiator based on potato peel peroxidase, vitamin C and H2O2 (PP/VC/H2O2) is used for free
radical polymerization of methacrylic acid. Fifty million tons of global potato peel waste is generated annually,
so isolation of active substances, such as peroxidase is a favorable solution from economic and environmental
aspects. By employing the PP/VC/H2O2 initiator, pH sensitive hydrogels based on poly(methacrylic acid)
(PMAA) can be successfully prepared by simple, energy efficient and sustainable synthesis under ambient conditions.
The reaction time and the required amount of H₂O₂ are significantly reduced (to 8 h and 30 μL,
respectively) compared to the method employing H₂O₂/VC initiation system, in which reaction is completed after
24 h and requires 100 μL of H2O2. Various techniques are used for characterization of the PMAA hydrogels: DSC,
XRD, FTIR, SEM and single compression tests. PP is analyzed, and its optimal pH and temperature, specific
activity, and RZ factor, are determined. Considering that inflammation can cause damage to the human body and
lead to many serious diseases (such as osteoarthritis), anti-inflammatory drug - dexamethasone is encapsulated in
the PMAA hydrogels. Controlled release of dexamethasone lasts 24 h. The PMAA swelling properties and
dexamethasone release are investigated depending on various synthesis parameters in media with different pH
values. The anti-inflammatory effect of the PMAA hydrogel with dexamethasone is tested on bovine chondrocytes.
Results show that PMAA hydrogels have anti-inflammatory effect with properties achieved through
mild, eco-friendly, economical, and tunable synthesis conditions
Production and characterization of biochar and modified biochars by carbonization process of bearberry (Arctostaphylos uva-ursi. L.): Adsorption capacities and kinetic studies of Pb2+, Cd2+ and rhodamine B removal from aqueous solutions
No full textIn this work, Bearberry (Arctostaphylos uva-ursi L.) leaves and twigs were used as novel biomass source for production of biochar and modified biochars (manufacturing of microporous and mesoporous carbons by physical and chemical activations, using CO2 and H3PO4) via one-step carbonization (800 °C) with excellent physicochemical properties, for effective removal of Pb2+ and Cd2+ ions, and synthetic dye (Rhodamine B - RhB) from aqueous solutions. Results showed that carbonized (BL-C) and physically activated carbons (BL-CO2) as microporous adsorbents (specific surface areas 219.0 m2/g and 305.5 m2/g) show remarkable removal efficiency of Pb2+ (99.8 % and 99.9 %, for BL-C and BL-CO2), while these adsorbents showed moderate affinity for Cd2+ elimination (53.5 % and 48.5 %). BL-H3PO4 as mesoporous adsorbent with lower specific surface and larger pores (90.2 m2/g with Dmax = 33.6 nm), shows very good removal efficiency of PhB (~ 87 %). It was found that physical adsorption occurs during RhB removal onto BL-H3PO4, where dominant mechanism represents film diffusion, with reduced boundary layer effect. Adsorption process takes place over π–π, hydrogen bonding and electrostatic interactions. Adsorption processes of Pb2+ and Cd2+ onto BL-CO2 and BL-C take place via physical and chemical adsorption, but with different type of mechanism, including combination of diffusion and chemisorption (increased effect of boundary layer) and intra-particle diffusion (greatly reduced boundary layer effect), respectively. A very interesting fact found in this study, is that metal oxide surfaces (as Cu2O, SiO2, ZnO present in activated carbons) exhibit an efficient binding towards cadmium, providing physisorption capability onto non-metallic graphene features