The development of surface technologies to obtain improved tribomechanical and biological characteristics of synthetic NiTi implants is critical. A suitable match with the mechanical properties of the implanted biomaterial is necessary to reduce the risk of stress-shielding and implantation failure. The present contribution has attempted to assess the influence of the Nb₂O₅ particle level in an electrolyte, i.e., 0–1 g L⁻¹, on the tribomechanical and biological performance of the HAp layers, which were obtained by galvanostatic pulse electrodeposition on NiTi. The surface characteristics of the electrodeposited layers were analyzed using GIXRD, FESEM, XPS, and contact angle measurements. Nanoindentation, nanoscratch, and pull-off assays were employed to study the tribomechanical properties of the films. The in vitro biocompatibility of the developed specimens was investigated using NIH3T3 fibroblast cells. The results illustrated that a more compact and hydrophilic surface is obtained with the incorporated particles. The Nb content and Ca/P molar ratio are increased from the outermost surface to the subsurface layers of the coatings. The composite coatings showed higher hardness, elastic modulus, bonding strength to the underlying NiTi, and lower COF compared to pure HAp layers. The elastic modulus of the Nb₂O₅-reinforced HAp films is close to that of cortical bone, reducing stress-shielding risk. The inclusion of Nb₂O₅ particles in the HAp matrix led to an improvement in cell functions, e.g., viability and proliferation, within the various cell culture durations. The adopted surface modification strategy in this work can create new opportunities for the successful use of NiTi in orthopedic applications.

Over the past decade, the development of three-dimensional (3D) models has increased exponentially, facilitating the unravelling of fundamental and essential cellular mechanisms by which cells communicate with each other, assemble into tissues and organs and respond to biochemical and biophysical stimuli under both physiological and pathological conditions. This section presents a concise overview of the most recent updates on the significant contribution of different types of 3D cell cultures including spheroids, organoids and organ-on-chip and bio-printed tissues in advancing our understanding of cellular and molecular mechanisms. The case studies presented include the 3D cultures of breast cancer (BC), endometriosis, the liver microenvironment and infections. In BC, the establishment of 3D culture models has permitted the visualization of the role of cancer-associated fibroblasts in the delivery of exosomes, as well as the significance of the physical properties of the extracellular matrix in promoting cell proliferation and invasion. This approach has also become a valuable tool in gaining insight into general and specific mechanisms of drug resistance. Given the considerable heterogeneity of endometriosis, 3D models offer a more accurate representation of the in vivo microenvironment, thereby facilitating the identification and translation of novel targeted therapeutic strategies. The advantages provided by 3D models of the hepatic environment, in conjunction with the high throughput characterizing various platforms, have enabled the elucidation of complex molecular mechanisms underlying various threatening hepatic diseases. A limited number of 3D models for gut and skin infections have been developed. However, a more profound comprehension of the spatial and temporal interactions between microbes, the host and their environment may facilitate the advancement of in vitro, ex vivo and in vivo disease models. Additionally, it may pave the way for the development of novel therapeutic approaches in diverse research fields. The interested reader will also find concluding remarks on the challenges and prospects of using 3D cell cultures for discovering cellular and molecular mechanisms in the research areas covered in this review.

Recent nanoapplications in diagnosis, therapy and theranostics of endometriosis, including the combination with phototherapy and a guideline for design for this type of approach.

The main problems in drug development are connected to enormous costs related to the paltry success rate. The current situation empowered the development of high‐throughput and reliable instruments, in addition to the current golden standards, able to predict the failures in the early preclinical phase. Being hepatotoxicity responsible for the failure of 30% of clinical trials, and the 21% of withdrawal of marketed drugs, the development of complex in vitro models (CIVMs) of liver is currently one of the hottest topics in the field. Among the different fabrication techniques, 3D‐bioprinting is emerging as a powerful ally for their production, allowing the manufacture of three‐dimensional constructs characterized by computer‐controlled and customized geometry, and inter‐batches reproducibility. Thanks to these, it is possible to rapidly produce tailored cell‐laden constructs, to be cultured within static and dynamic systems, thus reaching a further degree of personalization when designing in vitro models. This review highlights and prioritizes the most recent advances related to the development of CIVMs of the hepatic environment to be specifically applied to pharmaceutical research, with a special focus on 3D‐bioprinting, since the liver is primarily involved in the metabolism of drugs.

Bioprinting is a key technique to fabricate cell-laden volumetric constructs with controlled geometry. It can be used not only to replicate the architecture of a target organ but also to produce shapes that allow for the mimicry, in vitro, of specific desired features. Among the various materials suitable to be processed with this technique, sodium alginate is currently considered one of the most appealing because of its versatility. To date, the most widespread strategies to print alginate-based bioinks exploit external gelation as a primary process, by directly extruding the hydrogel-precursor solution into a crosslinking bath or within a sacrificial crosslinking hydrogel, where the gelation takes place. In this work, we describe the print optimization and the processing of Hep3Gel: an internally crosslinked alginate and ECM-based bioink for the production of volumetric hepatic tissue models. We adopted an unconventional strategy, by moving from the reproduction of the geometry and the architecture of liver tissue to the use of bioprinting to fabricate structures that can promote a high degree of oxygenation, as is the case with hepatic tissue. To this end, the design of structures was optimized by employing computational methods. The printability of the bioink was then studied and optimized through a combination of different a priori and a posteriori analyses. We produced 14-layered constructs, thus highlighting the possibility to exploit internal gelation alone to directly print self-standing structures with finely controlled viscoelastic properties. Constructs loaded with HepG2 cells were successfully printed and cultured in static conditions for up to 12 d, underlining the suitability of Hep3Gel to support mid/long-term cultures.

Upon delivery to CD44(+) endometriotic cells, Au@P_AbCD44 was internalised via clathrin-mediated endocytosis. Laser exposure of cells, based on LSPR properties, increased the temperature and promoted apoptotic over necrotic cell death.