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The zebrafish (Danio rerio) is a valuable model organism for studying human biology due to its easy genetic manipulation and small size. It is optically transparent and shares genetic similarities with humans, making it ideal for studying developmental processes, diseases, and drug screening via imaging-based approaches. Solid malignant tumors often contain hypoxic areas that stimulate the release of extracellular vesicles (EVs), lipid-bound structures released by cells into the extracellular space, that facilitate short- and long-range intercellular communication and metastatization. Here we investigate the effects of EVs derived from neuroblastoma (NB), a pediatric solid tumor, on metastatic niche formation using the zebrafish as an in vivo model. Intravascular injection in zebrafish embryos allows a non-invasive visualization of EVs dispersion, uptake, and interactions with host cells. To improve repeatability of our results and ease the injection steps, we used an agarose device replica molded from a custom designed micromilled aluminum mold. We first demonstrated that EVs released under hypoxic conditions promote angiogenesis and are more easily internalized by endothelial cells than those purified from normoxic cells. We also showed that injection of with hypoxic EVs increased macrophages mobilization. We then focused on the caudal hematopoietic tissue (CHT) region of the embryo as a potential metastatic site. After hypoxic EVs injection, we highlighted changes in the expression of mmp-9 and cxcl8b genes. Furthermore, we investigated the ability of NB-derived EVs to prime a metastatic niche by a two-step injection of EVs first, followed by NB cells. Interestingly, we found that embryos injected with hypoxic EVs had more proliferating NB cells than those injected with normoxic EVs. Our findings suggest that EVs released by hypoxic NB cells alter the behavior of recipient cells in the zebrafish embryo and promote metastatic outgrowth. In addition, we demonstrated the ability of the zebrafish embryo to be a suitable model for studying the interactions between EVs and recipient cells in the metastatic process. [ABSTRACT FROM AUTHOR]

Mycotoxins are among the most concerning natural toxic food contaminants. Over the years, significant efforts have been made to characterize the risk associated with their exposure. However, assessing their toxicity has so far been elusive due to the lack of adequate models that closely mimic the physiological conditions of human cells in vivo. Here, we present the SpheroFlow Device (SFD), an efficient microfluidic platform designed, manufactured, and validated to evaluate mycotoxin-induced cytotoxicity under dynamic and continuous exposure in 3D culture settings. In the present study, we integrated human neuroblastoma SH-SY5Y spheroids into the SFD to assess the acute toxicity induced by the mycotoxins ochratoxin A (OTA) and patulin (PAT). The developed system enabled qualitative and quantitative measurements of concentration–response relationships and provided accurate control over the culture microenvironment. Our findings show that by enhancing 3D culture model by applying dynamic flow, SH-SY5Y spheroids exhibited different sensitivities to OTA and PAT compared to conventional static SH-SY5Y spheroids, confirming the critical role of culture models in mycotoxin toxicity assessment. This is the first study assessing the neurotoxicity of OTA and PAT on 3D neuroblastoma spheroids considering the contribution of fluid flow. [ABSTRACT FROM AUTHOR]

Wearable technologies are attracting increasing attention in the materials science field, prompting a quest for active components with beneficial functional attributes whilst ensuring human and environmental safety. Hydrogels are highly biocompatible platforms with interesting mechanical properties, which can be exploited for the construction of strain sensors. In order to improve the directionality of their strain response and combine it with electrical properties to fabricate piezoresistive devices, it is possible to incorporate various types of nanofillers within the polymeric network of the hydrogels. 2D materials are ideal nanofillers thanks to their intrinsic two‐dimensional anisotropy and unique electronic properties. Herein, the covalent functionalization of 2D 1T‐MoS2 is exploited to build robust hybrid cross‐linked networks with a polyethylene glycol diacrylate gel (PEGDA). The conductivity of this nanocomposite is also further improved by inducing the interfacial polymerization of aniline. The resulting free‐standing samples demonstrate a linear and highly reversible piezoresistive response in a pressure range compatible with that of peripheral blood, while also featuring good compatibility with human skin cells, thereby making them interesting options for incorporation into wearable strain sensors. [ABSTRACT FROM AUTHOR]

Small-vessel disease is the most frequent cause of lacunar stroke. The aims of this study were to evaluate: 1) alternative causes of lacunar stroke other than small-vessel disease; 2) functional outcome of lacunar strokes due to small vessel disease compared to lacunar strokes due to alternative causes. Consecutive patients with first-ever ischemic lacunar stroke were prospectively followed-up for at least 3 months. At discharge patients were divided into 2 groups: lacunar stroke due to small vessel disease (L-SVD) and lacunar stroke due to possible other etiologies (L-non SVD) (e. g. cardioembolism, atherosclerosis or other causes). Main outcome measures were the combined end point of death or disability (mRS ≥ 3) and recurrent stroke at the end of follow-up. 535 patients with acute stroke were seen during the study period. Out of these, 196 patients (126 males) with a mean age of 71.6 years (SD = 10) had lacunar stroke. L-SVD was seen in 142 patients (72.4 %) and L-nonSVD in 54 patients (27.6 %). After 16.4 months, 12 patients had died (6.2%; annual mortality rate 4.4 %), 63 were disabled (32.5 %) and 27 had stroke recurrence (13.9%; annual recurrence rate 9.9 %). Forty-nine patients with L-SVD (34.7 %) and 26 with L-nonSVD (49%) had died or become disabled. Sixteen patients with L-SVD (11.3 %) and 11 with L-nonSVD (20.4 %) had stroke recurrence. On multivariate analysis, L-nonSVD (OR = 2.87, 95% CI 1.08–7.65; p = 0.034) and age (OR = 1.07, 95 % CI 1.02–1.12; p = 0.01) were associated to more severe outcome. L-nonSVD was independently associated with recurrence (OR = 5.03, 95% CI 1.54–16.44; p = 0.006). Twenty-seven percent of patients with lacunar stroke have causes other than small vessel disease. These patients have a severe outcome in terms of recurrence,mortality or disability. These findings support the need for a comprehensive diagnostic work-up for patients with lacunar stroke. [ABSTRACT FROM AUTHOR]

Despite contributing to cancer progression, extracellular vesicles (EVs) could serve as potential drug delivery systems in cancer treatment, having the ability to dissolve water-insoluble drugs and facilitate targeted delivery. However, the clinical translation of EVs is still in its infancy. While traditional methods for EV modifications will remain relevant, microfluidic approaches are expected to replace benchtop methods. Taking advantage of lab-on-chip devices, passive cargo loading through microfluidic mixing and incubation may be an important strategy to produce functional engineered EVs. This study focuses on developing a microfluidic device to generate EVs loaded with verteporfin (VP), a hydrophobic porphyrin with potential applications in neuroblastoma (NB) therapy, aiming to enhance its therapeutic effectiveness. The platform ensures perfect mixing and tunable incubation time for mesenchymal stem cell-derived EVs and VP, demonstrating a significantly higher loading efficiency than traditional methods, while operating under gentle conditions that preserve EV integrity and functionality, unlike other microfluidic techniques that involve harsh mechanical or chemical treatments. The VP-loaded EVs (VP-EVs) can then be easily recovered, making them available for subsequent analysis and use. MTT assay confirmed that VP-EVs are more efficient than free VP in reducing the viability of a NB cell line. Finally, immunofluorescence assay and western blot demonstrated a greater reduction in YAP expression after treatment with VP-EVs in an NB cell line when compared to free VP. Being both non-destructive and straightforward, this microfluidic loading technique facilitates its adaptability to a wide spectrum of therapeutic compounds. As a versatile tool, microfluidic technology will help to fully unlock the potential of EVs for speeding up precision medicine and disease treatment.