Search Results (58,276)

Cellular heterogeneity, an inherent feature of biological systems, plays a critical role in processes such as development, immune response, and disease progression. Human mesenchymal stem cells (hMSCs) exemplify this heterogeneity due to their multi-lineage differentiation potential. However, their inherent variability complicates clinical use, and there is no universally accepted method for detecting and quantifying cell population heterogeneity. Dielectrophoresis (DEP) has emerged as a powerful electrokinetic technique for characterizing and manipulating cells based on their dielectric properties, offering label-free analysis capabilities. Quantitative information from the DEP spectrum, such as transient slope, measure cells’ transition between negative and positive DEP behaviors. In this study, we employed DEP to estimate transient slope of various cell populations, including relatively homogeneous HEK-293 cells, heterogeneous hMSCs, and cancer cells (PC3 and DU145). Our analysis encompassed hMSCs derived from bone marrow, adipose, and umbilical cord tissue, to capture tissue-specific heterogeneity. Transient slope was assessed using two methods, involving linear trendline fitting to different low-frequency regions of the DEP spectrum. We found that transient slope serves as a reliable indicator of cell population heterogeneity, with more heterogeneous populations exhibiting lower transient slopes and higher standard deviations. Validation using cell morphology, size, and stemness further supported the utility of transient slope as a heterogeneity metric. This label-free approach holds promise for advancing cell sorting, biomanufacturing, and personalized medicine. Full article

Nanocomposites based on Fe₃O₄ and carbonaceous nanoparticles (CNPs), including carbon nanotubes (CNTs) and graphene derivatives (graphene oxide (GO) and reduced graphene oxide (RGO)), such as Fe₃O₄@GO, Fe₃O₄@RGO, and Fe₃O₄@CNT, have demonstrated considerable potential in a number of health applications, including tissue regeneration and innovative cancer treatments such as hyperthermia (HT). This is due to their ability to transport drugs and generate localized heat under the influence of an alternating magnetic field on Fe₃O₄. Despite the promising potential of CNTs and graphene derivatives as drug delivery systems, their use in biological applications is hindered by challenges related to dispersion in physiological media and particle agglomeration. Hence, a solid foundation has been established for the integration of various synthesis techniques for these nanocomposites, with the wet co-precipitation method being the most prevalent. Moreover, the dimensions and morphology of the composite nanoparticles are directly correlated with the value of magnetic saturation, thus influencing the efficiency of the composite in drug delivery and other significant biomedical applications. The current demand for this type of material is related to the loading of a larger quantity of drugs within the hybrid structure of the carrier, with the objective of releasing this amount into the tumor cells. A second demand refers to the biocompatibility of the drug carrier and its capacity to permeate cell membranes, as well as the processes occurring within the drug carriers. The main objective of this paper is to review the synthesis methods used to prepare hybrids based on Fe₃O₄ and CNPs, such as GO, RGO, and CNTs, and to examinate their role in the formation of hybrid nanoparticles and the correlation between their morphology, the dimensions, and optical/magnetic properties. Full article

This study introduces a novel method for the fabrication of concave microwells involving water vapor permeation through polydimethylsiloxane (PDMS). This method leverages the exceptional water vapor permeability of PDMS to enable a scalable and cost-effective fabrication process, addressing the limitations of existing techniques such as photolithography that are resource-intensive and complex. PDMS is more permeable to water vapor than to other gas molecules, resulting in the formation of microwells. Smooth-sloped concave microwells are formed by depositing droplets of 10% ethylene glycol on a PDMS substrate followed by curing at 70 °C and evaporation of water vapor. These microwells exhibit a unique structural gradient that is highly conducive for biological applications. Concave microwells were further used as a platform to generate animal cell spheroids, demonstrating their potential for three-dimensional cell culture. Unlike conventional methods, this approach allows precise control over microwell morphology by simply adjusting droplet size and curing conditions, offering enhanced tunability and reproducibility. The formation yield of these microwells is dependent on the volume of the water droplets, demonstrating the importance of droplet size in controlling microwell morphology. This approach provides a simple and effective method for creating microwells without complex lithographic processes, making it a highly promising tool for a range of biomedical applications, including tissue engineering, cancer research, and high-throughput drug screening. Full article

This study aimed to evaluate the influence of indirect-plasma-treated water (IPTW) in the preparation of hydrogels. Three commonly used natural, biodegradable polymers with the ability to form gels were selected: gelatin, carrageenan, and sodium alginate. The pH, gelling temperature, texture profile, swelling degree, and color of hydrogels were evaluated, and the polymers were subjected to Fourier-transform infrared (FTIR) spectroscopy. The morphology of the hydrogels was investigated using Scanning Electron Microscopy (SEM). Additionally, the physiochemical properties of the water media, which were distilled water (DW) and IPTW, were analyzed. The results indicated that the gels prepared using IPTW were characterized by a lower pH, higher hardness and lower gelation temperature. After 48 h of swelling ratio (SR) testing, gelatin and alginate hydrogels made with IPTW were characterized by lower SR, while an inverse relationship was found in the case of SR of carrageenan gels. The FTIR analysis confirmed changes in the water binding ability. The use of IPTW also significantly affected the microstructure of the tested materials. A statistically significant change in the color of IPTW gel samples was also noted. The results showed that IPTW induces physicochemical changes in hydrogels, which can lead to the enhancement of their practical applications. Full article

Urban elements influence atmospheric flow, turbulence, and the local microclimate, modifying the transport and composition of pollutants. However, although this focus on cities is crucial for managing climate change, our knowledge of most cities in the world is still quite limited. Thus, the classification of Local Climate Zones (LCZs) aims to increase the accuracy of urban studies and has already been applied in various regions of the world, including, more recently, in Brazil. This article aimed to apply the LCA to Santarém, a city in the Brazilian Amazon. The methodological procedures included the digital mapping protocol of the World Urban Database and Access Portal Tools (WUDAPT-Level 0) and the supervised classification tool of the LCZ Generator application, resulting in 78 polygons representing 10.02% of the training area and 13.94% of the study area (urban zone). The research identified 7 of the 17 main LCZ classes in Santarém. The use of the NDVI was essential for assessing the vegetation in each class, highlighting variations in green areas and emphasizing that vegetation is reduced in built environments. This approach enhances the understanding of urban morphology and enables future research into urbanization and the climate in the Amazon. Full article

Cadmium (Cd) is one of the foremost phytotoxic elements. Its proportion in agricultural soil is increasing critically due to anthropogenic activities. Cd stress is a major crop production threat affecting food security globally. Triacontanol (TRIA) is a phytohormone that promotes growth, development, and metabolic processes in plants. The current study explicates the mitigation of Cd toxicity in Vigna radiata L. (mung bean) seedlings through the application of TRIA by a seed priming technique under Cd stress. The role of TRIA in improving metabolic processes to promote Vigna radiata (mung bean, green gram) vegetative growth and performance under both stressed and unstressed conditions was examined during this study. To accomplish this, three doses of TRIA (10, 20, and 30 µmol L⁻¹) were used to pretreat V. radiata seeds before they were allowed to grow for 40 days in soil contaminated with 20 mg kg⁻¹ Cd. Cd stress lowered seed germination, morphological growth, and biomass in V. radiata plants. The maximum root and shoot lengths, fresh and dry weights of roots, and shoot and seed germination rates were recorded for TRIA2 compared with those of TRIA1 and TRIA3 under Cd stress. In Cd-stressed V. radiata plants, TRIA2 increased the content of chlorophyll a (2.1-fold) and b (3.1-fold), carotenoid (4.3-fold), total chlorophyll (3.1-fold), and gas exchange attributes, such as the photosynthetic rate (2.9-fold), stomatal conductance (6.0-fold), and transpiration rate (3.5-fold), compared with those in plants treated with only Cd. TRIA seed priming increased nutrient uptake (K¹⁺, Na¹⁺, Mg²⁺, and Zn²⁺), total phenolic content, total soluble protein content, and DPPH (2,2-diphenyl-1-picrylhydrazyl) activity. Additionally, TRIA2 significantly reduced the quantity of Cd in the plants (3.0-fold) and increased the metal tolerance index (6.6-fold) in plants contrasted with those in the Cd-treated plants. However, TRIA2 promoted plant growth and biomass production by lowering Cd-induced stress through modifying the plant antioxidant machinery and reducing oxidative stress. The improved yield characteristics of V. radiata seedlings treated with TRIA suggest that exogenous TRIA may be used to increase plant tolerance to Cd stress. Full article

This study investigates the effects of homopolymer additives and kinetic traps on the self-assembly of poly(ethylene glycol)-b-poly(lactide) (PEG-PLA) block copolymer (BCP) nanostructures in aqueous environments. By using non-adsorbing PEG homopolymers to kinetically trap PEG-PLA nanostructures, we demonstrate that varying the concentration and molecular weight of the added PEG induces a reversible micelle-to-vesicle transition. This transition is primarily driven by changes in the molecular geometry of the PEG-PLA BCPs due to excluded volume screening effects. Additionally, the reversible vesicle-to-micelle transition upon PEG’s removal shows time and temperature dependency, highlighting the influence of the system’s kinetic nature. Intermediate structures observed during the transition support a mechanism based on shifts in the molecular geometry of PEG-PLA. As a proof of concept, we show that PEG-PLA vesicles can act as thermoresponsive delivery systems, retaining dye at low temperatures (4 °C) and releasing it upon heating (37 °C). Overall, this work presents a novel approach to controlling BCP nanostructures’ morphology, with implications for drug delivery and material science applications. Full article

In the present work, we achieved the fabrication of MgO-Fe₂O₃/γ-Al₂O₃ NCs using a deposition–coprecipitation process. XRD, TEM, and SEM with EDX, XPS, FTIR, and PL spectroscopy were applied to examine the physicochemical properties of the samples. XRD analysis confirmed the successful incorporation of γ-Al₂O₃, MgO, and Fe₂O₃ phases. TEM and SEM images indicate that the nanocomposites exhibited an agglomerated morphology with spherical shapes and particle sizes in the range of 6–12 nm. EDX and XPS spectra revealed a composition of MgO-Fe₂O₃/γ-Al₂O₃ NCs. FTIR spectra identified characteristic vibrational bands corresponding to the chemical bonds present in the samples, confirming their successful synthesis. PL analysis showed the reduced recombination rate of electron–hole pairs and enhanced charge separation efficiency, which are important factors for improved photocatalytic activity. Photocatalysis results show that the MgO-Fe₂O₃/γ-Al₂O₃ NCs exhibited significantly higher photocatalysis efficiencies of 87.5% for Rh B and 90.4% for MB after 140 min, compared to γ-Al₂O₃ NPs and Fe₂O₃/γ-Al₂O₃ NPs. In addition, prepared MgO-Fe₂O₃/γ-Al₂O₃ NCs demonstrated superior stability after six runs. Biochemical data showed that the MgO-Fe₂O₃/γ-Al₂O₃ NCs exhibited significant toxicity toward A549 cancer cells while displaying low toxicity toward IMR90 normal cells. The IC₅₀ values (µg/mL ± SD) for γ-Al₂O₃ NPs, Fe₂O₃/γ-Al₂O₃ NPs, and MgO-Fe₂O₃/γ-Al₂O₃ NCs were 16.54 ± 0.8 µg/mL, 14.75 ± 0.4 µg/mL, and 11.40 ± 0.6 µg/mL, respectively. These results suggest that the addition of Fe₂O₃ and MgO to γ-Al₂O₃ not only enhances photocatalytic activity but also improves biocompatibility and anticancer properties. This study highlights that the MgO-Fe₂O₃/γ-Al₂O₃ NCs warrant further exploration of their potential applications in environmental remediation and biomedicine. Full article

The study aimed to explore if milkability parameters could reliably predict the dimensions of teat structures and their milking-induced changes. Ultrasonography repeatedly measured the teat structures of 48 Holstein cows from mid to late lactation. We found that milking-induced changes in each structure are affected by different milkability parameters. Regression models for teat canal change and length change were significant, and variability was found to be 46.03% and 21.50%, respectively. Similarly, the teat structure’s dimensions significantly affected milkability parameters, which differed for each structure. However, regression models only explained between 3.36% (teat length) and 7.59% (cistern) of variability. The prediction potential, performed based on milkability, is limited if the initial dimensions of structures are not provided. If teat dimensions were measured at the beginning of the production life, automatically collected milkability data could be used to calculate milking-induced changes incurred with each milking and the development of teat dimensions over the production life. If perfected, this tool could provide alerts about critical milking-induced changes and risky teat conformation traits, as they have a proven effect on udder health and are reliable indicators of milking effectiveness. Full article

In confined and intricate aquatic environments, fish frequently encounter the need to propel themselves under oblique flow conditions. This study employs a self-developed ghost-cell immersed boundary method coupled with GPU acceleration technology to numerically simulate the propulsion dynamics of flexible biomimetic fish swimming in oblique flow environments. This research scrutinizes diverse biomimetic fish fin morphologies, with particular emphasis on variations in the Strouhal number and angle of attack, to elucidate hydrodynamic performance and wake evolution. The results demonstrate that as the fin thickness increases, the propulsion efficiency decreases within the Strouhal number range of St = 0.2, 0.4. Conversely, within the range of St = 0.6 to 1.0, the efficiency variations stabilize. For all three fin morphologies, an increase in the Strouhal number significantly augmented both the lift-to-drag ratio and thrust, concomitant with a transition in the wake structure from smaller vortices to a larger alternating vortex shedding pattern. Furthermore, within the Strouhal number range of St = 0.2 to 0.4, the propulsion efficiency exhibits an increase, whereas in the range of St = 0.6 to 1.0, the propulsion efficiency stabilizes. As the angle of attack increases, the drag coefficient increases significantly, while the lift coefficient exhibits a diminishing rate of increase. An increased fin thickness adversely affects the hydrodynamic performance. However, this effect attenuates at higher Strouhal numbers. Conversely, variations in the angle of attack manifest a more pronounced effect on hydrodynamic performance. A thorough investigation and implementation of the hydrodynamic mechanisms demonstrated by swimming fish in complex flow environments enables the development of bio-inspired propulsion systems that not only accurately replicate natural swimming patterns, but also achieve superior locomotion performance and robust environmental adaptability. Full article

A large sample of 65 individuals of the recently described goby Zebrus pallaoroi was collected in France. The species identity of these individuals was confirmed based on morphology. In addition, the species identity was validated through genetic analysis for one of the two specimens collected from the new depth records for the species. The diagnostic characters of Z. pallaoroi, originally based on a limited number of type specimens, were tested on this larger sample and critically analyzed. The diagnostic characters of Z. pallaoroi were revised, and recommendations were made for improving the study of diagnostic characters in gobiid species description, particularly when based on small sample sizes. The record of Z. pallaoroi in the western Mediterranean significantly expands its known geographic range, increases the maximum recorded depth of the species, and reveals syntopic co-occurrence with its phylogenetically closest relatives. Full article

Major depressive disorder (MDD) exhibits notable sex differences in prevalence and clinical and neurobiological manifestations. Though the relationship between peripheral inflammation and MDD-related brain changes is well studied, the role of sex as a modifying factor is underexplored. This study aims to assess how sex influences brain and inflammatory markers in MDD. We utilized voxel-based and surface-based morphometry to analyze gray matter (GM) structure, along with GM-based spatial statistics (GBSS) to examine GM microstructure among treatment-naive patients with depression (n = 174) and age-matched healthy controls (n = 133). We uncovered sex-by-diagnosis interactions in several limbic system structures, the frontoparietal operculum and temporal regions. Post hoc analyses revealed that male patients exhibit pronounced brain abnormalities, while no significant differences were noted in females despite their higher depressive scores. Additionally, heightened inflammation levels in MDD were observed in both sexes, with sex-specific effects on sex-specific brain phenotypes, particularly including a general negative correlation in males. Intriguingly, mediation analyses highlight the specific role of the parahippocampal gyrus (PHG) in mediating interleukin (IL)-8 and depression in men. The findings suggest that in clinical practice, it would be beneficial to prioritize sex-specific assessments and interventions for MDD. This includes recognizing the possibility that male patients may experience significant brain alterations, especially when identifying male patients who may underreport symptoms. Possible limitations encompass a small sample size and the cross-sectional design. In future research, the incorporation of longitudinal studies or diverse populations, while considering illness duration, will enhance our understanding of how inflammation interacts with brain changes in depression. Full article

In this work, an effective route for achieving high-performance all-polymer materials through the proper manipulation of the material microstructure and starting from a waste material is proposed. In particular, recycled polyethylene terephthalate (rPET) fibers from discarded safety belts were used as reinforcing phase in melt-compounded high-density polyethylene (HDPE)-based systems. The formulated composites were subjected to hot- and cold-stretching for obtaining filaments at different draw ratios. The performed characterizations pointed out that the material morphology can be profitably modified through the application of the elongational flow, which was proven able to promote significant microstructural evolutions of the rPET dispersed domains, eventually leading to the obtainment of micro-fibrillated all-polymer composites. Furthermore, tensile tests demonstrated that hot-stretched and, especially, cold-stretched materials show significantly enhanced tensile modulus and strength as compared to the unfilled HDPE filaments, likely due to the formation of a highly oriented and anisotropic microstructure. Full article

This study explores biochar (BC) derived from date palm seeds as a high-performance adsorbent for the removal of trichloroethylene (TCE) and tetrachloroethylene (PCE) from aqueous solutions, with comparative analysis against commercial activated carbon (AC). The optimized BC, characterized by a high BET surface area of 654.79 m²/g and unique nanotube morphology, demonstrated superior adsorption capacities of 86.68 mg/g for TCE and 85.97 mg/g for PCE, significantly surpassing the AC under identical conditions. Kinetic studies identified the pseudo-second-order model as the best fit, indicating chemisorption as the dominant mechanism. Isotherm modeling revealed a combination of multilayer and monolayer adsorption processes, underscoring the complexity of the BC’s adsorption behavior. Statistical analysis via two-way ANOVA further validated the BC’s significant superiority over the AC (p < 0.0001) for both contaminants. These results highlight the potential of date-palm-seed-derived biochar as a sustainable and cost-effective adsorbent for eco-friendly water treatment, emphasizing its role in reducing environmental impact and operational costs in real-world applications. Full article

Carbapenem-resistant Enterobacterales (CRE) is an emerging global concern. Specifically, carbapenemase-producing (CP) E. coli strains in CRE have recently been found in clinical, environmental, and food samples worldwide, causing many hospitalizations and deaths. Their rapid identification and characterization are paramount in control, management options, and treatment choices. Thus, this study aimed to characterize the cell surface properties of carbapenem-resistant (R) E. coli isolates and their interaction with glycan-coated magnetic nanoparticles (gMNPs) compared with carbapenem-susceptible (S) E coli. This study used two groups of bacteria: The first group included E. coli (R) isolates harboring carbapenemases and had no antibiotic exposure. Their initial gMNP–cell binding capacity, with cell surface characteristics, was assessed. In the second group, one of the E. coli (R) isolates and E. coli (S) had long-term serial antibiotic exposure, which we used to observe their cell surface characteristics and gMNP interactions. Initially, cell surface characteristics (cell morphology and cell surface charge) of the E. coli isolates were evaluated using confocal laser scanning microscope (LSCM) and a Zetasizer, respectively. The interaction of gMNPs with the E. coli isolates was assessed through LSCM and transmission electron microscope (TEM). Further, the gMNP–cell attachment was quantified as a concentration factor (CF) through the standard plating method. The results showed that the CF values of all E. coli (R) were significantly different from those of E. coli (S), which could be due to the differences in cell characteristics. The E. coli (R) isolates displayed heterogeneous cell shapes (rod and round cells) and lower negative zeta potential (cell surface charge) values compared to E. coli (S). Further, this research identified the differences in the cell surface characteristics of E. coli (S) under carbapenem exposure, compared to unexposed E. coli (S) that impact their attachment capacity. The gMNPs captured more E. coli (S) cells compared to carbapenem-exposed E. coli (S) and all E. coli (R) isolates. This study clearly found that differences in cell surface characteristics impact their interaction with magnetic nanoparticles. The gained insights aid in further understanding adhesion mechanisms to develop or improve bacterial isolation techniques and diagnostic and treatment methods for CRE. Full article