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Heating magnetic nanoparticles (MNPs) with AC (Alternating Current) magnetic fields has received significant attention in recent years, particularly for biomedical uses. However, most studies focus on characterizing the heat release, overlooking the fact that the MNPs in the viscous cell environment constitute a dynamic magnetic colloid whose configuration may evolve over time, particularly if a driving force as the AC field is applied. Aiming to shed light on this matter, in this workthe dynamics of the colloid structure during hyperthermia experiments are studied. By combining various experimental and theoretical tools, it is concluded that the AC field may drive the formation of aligned structures, and the impact that such structures may have on the associated heating is assessed. Remarkably, the results show that those field‐driven structures are highly unstable for small particle sizes, rapidly disassembling upon field removal. Moreover, an analogous behavior in vitro is found, with the AC magnetic field also promoting a reversible alignment of vesicles containing the MNPs within the cells. The results suggest that the observed alignment, both of MNPs and intracellular vesicles, may be a common phenomenon in usual hyperthermia experiments, but unnoticed because of the intrinsic unstable nature of the aligned structures. [ABSTRACT FROM AUTHOR]

One of the hallmarks of tissue repair is the production of reactive oxygen species (ROS), which modulate processes such as cell proliferation. Although several attempts have been made to manipulate ROS levels to increase tissue repair, the lack of techniques able to remotely manipulate the redox homeostasis with spatio–temporal fashion has hindered its progress. Herein, a new approach for tuning the ROS levels using magnetic nanoparticles (MNPs) that act as nanoheaters when exposed to an alternating magnetic field is presented. Two manganese–iron oxide (MnxFe3−xO4) MNPs (with a low and a high Mn2+ content) are designed and probed for the possibility of modulating the ROS balance by magneto–thermal stimulation in the invertebrate model organism Hydra vulgaris, able to fully regenerate. By evaluating the expression of selected genes involved in the maintenance of ROS homeostasis and proliferation pathways, a biphasic modulation of the ROS levels played by the MNPs is found. While MNPs with a lower Mn2+ content are able to positively modulate the regeneration potential under magnetostimulation, MNPs with a higher Mn2+ content cause a different redox imbalance, negatively affecting the regeneration dynamic. This innovative approach reveals a novel way of manipulating redox homeostasis that can advance in the field of tissue engineering. [ABSTRACT FROM AUTHOR]

The accumulation of senescent cells, a hallmark of aging and age-related diseases, is also considered as a side effect of anticancer therapies, promoting drug resistance and leading to treatment failure. The use of senolytics, selective inducers of cell death in senescent cells, is a promising pharmacological antiaging and anticancer approach. However, more studies are needed to overcome the limitations of first-generation senolytics by the design of targeted senolytics and nanosenolytics and the validation of their usefulness in biological systems. In the present study, we have designed a nanoplatform composed of iron oxide nanoparticles functionalized with an antibody against a cell surface marker of senescent cells (CD26), and loaded with the senolytic drug HSP90 inhibitor 17-DMAG (MNP@CD26@17D). We have documented its action against oxidative stress-induced senescent human fibroblasts, WI-38 and BJ cells, and anticancer drug-induced senescent cutaneous squamous cell carcinoma A431 cells, demonstrating for the first time that CD26 is a valid marker of senescence in cancer cells. A dual response to MNP@CD26@17D stimulation in senescent cells was revealed, namely, apoptosis-based early response (2 h treatment) and ferroptosis-based late response (24 h treatment). MNP@CD26@17D-mediated ferroptosis might be executed by ferritinophagy as judged by elevated levels of the ferritinophagy marker NCOA4 and a decreased pool of ferritin. As 24 h treatment with MNP@CD26@17D did not induce hemolysis in human erythrocytes in vitro , this newly designed nanoplatform could be considered as an optimal multifunctional tool to target and eliminate senescent cells of skin origin, overcoming their apoptosis resistance.

BackgroundBy mid-September 2023, several event notifications related to cryptosporidiosis had been identified from different regions in Spain. Therefore, a request for urgent notification of cryptosporidiosis cases to the National Surveillance Network was launched.AimWe aimed at assessing the extent of the increase in cases, the epidemiological characteristics and the transmission modes and compared to previous years.MethodsWe analysed data on case notifications, outbreak reports and genotypes focusing on June-October 2023 and compared the results to 2016-2022.ResultsIn 2023, 4,061 cryptosporidiosis cases were notified in Spain, which is an increase compared to 2016-2022. The cumulative incidence was 8.3 cases per 100,000 inhabitants in 2023, sixfold higher than the median of 1.4 cases per 100,000 inhabitants 2016-2022. Almost 80% of the cases were notified between June and October. The largest outbreaks were related to contaminated drinking water or swimming pools. Cryptosporidium hominis was the most common species in the characterised samples (115/122), and the C. hominis IfA12G1R5 subtype, previously unusual in Spain, was detected from 76 (62.3%) of the 122 characterised samples.ConclusionsA substantial increase in cryptosporidiosis cases was observed in 2023. Strengthening surveillance of Cryptosporidium is essential for prevention of cases, to better understand trends and subtypes circulating and the impact of adverse meteorological events.