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• Co-milling of fresh chili peppers and olives was proposed for flavouring of olive oil. • Oils obtained by co-milling and infusion showed similar capsaicinoids profiles. • Oils from infusion were rich in acetic acid and presented the winey/vinegary defect. • Oils from co-milling were characterized by volatile esters and were free from defects. • Co-milling with red or green chili determined different sensory and volatile profiles. In the context of the olive oil flavoured with chili peppers, the aim of this study was to compare co-milling of sound olives and fresh chili peppers at mill scale to infusion of dried chili peppers in oil, using the same batch of olives for all oils. Capsaicinoids by HPLC-DAD, volatile profile by HS-SPME-GC-MS and HS-GC-IMS and sensory profile were characterized. Capsaicinoids were statistically higher in oils prepared with green (52.0–68.0 mg/kg) than red (48.0–60.2 mg/kg) chili peppers. Oils flavoured by infusion showed higher contents of volatile compounds linked to defects such as acetic acid, with winey/vinegary sensory defect (median, 1.72–2.02) and no fresh pepper flavour. Oils prepared by co-milling resulted rich in the typical esters of chili pepper (6.175 and 4.156 mg/kg with green and red chili peppers, respectively), with pleasant hotness sensation and fresh pepper flavour. Overall, the co-milling approach allowed obtaining flavoured samples with improved sensory quality. [ABSTRACT FROM AUTHOR]

• A novel layout for biomass waste torrefaction, CLC, and methanation is proposed. • LHV of agro-industrial residues torrefied at 300 °C increased by about 14–49 %. • A CO 2 -to-CH 4 conversion degree higher than 98% was evaluated. • Solar-driven torrefaction enhances the renewable footprint of the proposed process. To promote the integration between solar-driven torrefaction, Power-to-Gas, and Chemical Looping Combustion (CLC) systems, this work numerically analyzes the performances of a novel process layout. Several agro-industrial residues were considered as fuels. CuO supported on zirconia and Ni supported on alumina were considered as oxygen carrier and methanation catalyst, respectively. Torrefied samples were purposely obtained by means of experimental runs carried out for 30 min at 300 °C in a lab-scale fixed bed reactor under a nitrogen atmosphere. Under the adopted conditions it was attained an increase in the lower heating values (LHV) of the selected feedstocks by about 14–49 %, depending on the different composition and reactivity of the parent biomass. Based on these data, it was estimated that, with respect to 10 kg h−1 torrefied biomass fed to the CLC system, a total thermal power production in the range of 28–58 kW can be achieved. CO 2 conversion degrees of above 98 % were evaluated for the methanation unit in all considered scenarios. Considering different locations in Italy, PV field sizes ranging from 45 m2 up to 1392 m2 were evaluated for the solar-driven torrefaction unit. Wider sizes were calculated for the hydrogen production one, ranging from 3366 m2 up to 5598 m2. Eventually, an electric energy storage efficiency of around 16 % was assessed for the proposed layout. Finally, it was found that moving from the adopted torrefied feedstocks to the produced gaseous fuel, an increase in the LHV by about 44–55 % can be attained, while concurrently, CO 2 emissions are favorably decreased by 98 %. [ABSTRACT FROM AUTHOR]

Lipidic carriers are efficient vehicles preserving drugs during cell administration. Several production processes of lipidic nanoparticles were developed to reduce mean size at nanometric level, enhancing homogeneity and process replicability. However, lipidic aggregation has always been considered a huge drawback in terms of high polidispersity and instability. Looking at this problem from a different point of view, specific operating parameters were employed to produce Nanostructured Lipidic Carriers (NLC), whose structure simulates the complexity of cell barrier. NLC present high surface to volume ratio, and improved potential in terms of drug entrapment efficiency and bioavailability. In this work, NLCs were produced by studying the effect of process parameters, such as Drug to Lipid Ratio from 2:1–1:20 w/w. At macroscopic level, the NLCs produced showed these diameters distribution: D(10 %) from 85 nm to 6 µm, D(50 %) of about 10 µm and D(90 %) of about 31 µm. Encapsulation Efficiencies were measured from a minimum of 92.06 % to a maximum of 98.93 %, with mass yield included between 48.8 % and 99 %. Scanning Electron Microscope demonstrated the complexity of the shape of these NLCs, characterized by nanometric structures (100–500 nm) grab on Q10 "pillars" or adsorbed on lipidic external sheet. [Display omitted] • Nanostructured Lipidic Carriers loaded with Q10+B2. • Simultaneous 99 % entrapment of hydrophilic and lipophilic compounds. • Production of solvent-free innovative drug carrier. • Production of Q10 fibers acting as pillars in NLC. [ABSTRACT FROM AUTHOR]

Abstract: Combustion of two semi-dried sewage sludges in a 110mm has been characterized in terms of particulate and gaseous emissions. Sludges differed in that they had been conditioned – at the flocculation stage of wastewater treatment – either with Ca-based inorganics or with polyelectrolytes. Combustion was efficient for both sewage sludges under all the operating conditions tested. Significant differences have instead been observed between the two types of sewage sludges as regards particulate and macro-pollutant gaseous emissions (SO2, NOx). NOx formation is significantly influenced by ash accumulation inside the bed only when sewage sludge conditioned with Ca-based inorganics is fired. The time-resolved profiles of NOx concentration and the mass flow rate of the elutriated fines have been worked out to evaluate the fuel nitrogen yield to NOx as a function of ash accumulated inside the bed divided by the air mass feed rate. Experimental results have been compared with data present in literature. [Copyright &y& Elsevier]

In this work, an innovative process layout for methane production is proposed and investigated with the aim to promote the integration of renewable energies chemical storage via hydrogen production by water electrolysis and biomass gasification. The core of the proposed layout is the integration between an experimental fluidized bed gasification system, fed with spruce wood pellets and using Fe/Al 2 O 3 catalyst, and a conceptual methanation unit. This latter was modelled as a series of adiabatic fixed bed reactors with inter-cooling, water condensation at the exit of each reactor, and product recycle. The performance of the methanation system was evaluated by considering that the product stream coming from the gasifier system reacts, after purification and mixing with pure hydrogen coming from an electrolysis cells array, over Ni supported on alumina catalyst. The number of electrolysis cells to be stacked in the hydrogen production unit was evaluated by considering that a constant H 2 production able to reach 7:1:1H 2 :CO:CO 2 ratio at the inlet of the methanation unit should be attained. • Adding steam to air as gasification agent enhances the syngas H 2 :CO ratio. • Steam-and-air gasification lowers the H 2 request from water electrolysis. • High CO and CO 2 conversions are achieved in a multistage adiabatic methanation unit. • Syngas to methane could be a viable answer for renewable energies chemical storage. [ABSTRACT FROM AUTHOR]

Morphogenesis requires embryonic cells to generate forces and perform mechanical work to shape their tissues. Incorrect functioning of these force fields can lead to congenital malformations. Understanding these dynamic processes requires the quantification and profiling of three-dimensional mechanics during evolving vertebrate morphogenesis. Here we describe elastic spring-like force sensors with micrometre-level resolution, fabricated by intravital three-dimensional bioprinting directly in the closing neural tubes of growing chicken embryos. Integration of calibrated sensor read-outs with computational mechanical modelling allows direct quantification of the forces and work performed by the embryonic tissues. As they displace towards the embryonic midline, the two halves of the closing neural tube reach a compression of over a hundred nano-newtons during neural fold apposition. Pharmacological inhibition of Rho-associated kinase to decrease the pro-closure force shows the existence of active anti-closure forces, which progressively widen the neural tube and must be overcome to achieve neural tube closure. Overall, our approach and findings highlight the intricate interplay between mechanical forces and tissue morphogenesis., (© 2024. The Author(s).)

Three-dimensional hydrogel-based organ-like cultures can be applied to study development, regeneration, and disease in vitro. However, the control of engineered hydrogel composition, mechanical properties and geometrical constraints tends to be restricted to the initial time of fabrication. Modulation of hydrogel characteristics over time and according to culture evolution is often not possible. Here, we overcome these limitations by developing a hydrogel-in-hydrogel live bioprinting approach that enables the dynamic fabrication of instructive hydrogel elements within pre-existing hydrogel-based organ-like cultures. This can be achieved by crosslinking photosensitive hydrogels via two-photon absorption at any time during culture. We show that instructive hydrogels guide neural axon directionality in growing organotypic spinal cords, and that hydrogel geometry and mechanical properties control differential cell migration in developing cancer organoids. Finally, we show that hydrogel constraints promote cell polarity in liver organoids, guide small intestinal organoid morphogenesis and control lung tip bifurcation according to the hydrogel composition and shape., (© 2023. The Author(s).)

The human developmental processes during the early post-implantation stage instruct the specification and organization of the lineage progenitors into a body plan. These processes, which include patterning, cell sorting, and establishment of the three germ layers, have been classically studied in non-human model organisms and only recently, through micropatterning technology, in a human-specific context. Micropatterning technology has unveiled mechanisms during patterning and germ layer specification; however, cell sorting and their segregation in specific germ layer combinations have not been investigated yet in a human-specific in vitro system. Here, we developed an in vitro model of human ectodermal patterning, in which human pluripotent stem cells (hPSCs) self-organize to form a radially regionalized neural and non-central nervous system (CNS) ectoderm. We showed that by using micropatterning technology and by modulating BMP and WNT signals, we can regulate the appearance and spatial distribution of the different ectodermal populations. This pre-patterned ectoderm can be used to investigate the cell sorting behavior of hPSC-derived meso-endoderm cells, with an endoderm that segregates from the neural ectoderm. Thus, the combination of micro-technology with germ layer cross-mixing enables the study of cell sorting of different germ layers in a human context., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2022 Yang, Laterza, Stuart, Michielin, Gagliano, Urciuolo and Elvassore.)

The production of skeletal muscle constructs useful for replacing large defects in vivo, such as in congenital diaphragmatic hernia (CDH), is still considered a challenge. The standard application of prosthetic material presents major limitations, such as hernia recurrences in a remarkable number of CDH patients. With this work, we developed a tissue engineering approach based on decellularized diaphragmatic muscle and human cells for the in vitro generation of diaphragmatic-like tissues as a proof-of-concept of a new option for the surgical treatment of large diaphragm defects. A customized bioreactor for diaphragmatic muscle was designed to control mechanical stimulation and promote radial stretching during the construct engineering. In vitro tests demonstrated that both ECM remodeling and fibroblast overgrowth were positively influenced by the bioreactor culture. Mechanically stimulated constructs also increased tissue maturation, with the formation of new oriented and aligned muscle fibers. Moreover, after in vivo orthotopic implantation in a surgical CDH mouse model, mechanically stimulated muscles maintained the presence of human cells within myofibers and hernia recurrence did not occur, suggesting the value of this approach for treating diaphragm defects., (© 2022. The Author(s).)

Skeletal muscle is a dynamic tissue in which homeostasis and function are guaranteed by a very defined three-dimensional organization of myofibers in respect to other non-muscular components, including the extracellular matrix and the nervous network. In particular, communication between myofibers and the nervous system is essential for the overall correct development and function of the skeletal muscle. A wide range of chronic, acute and genetic-based human pathologies that lead to the alteration of muscle function are associated with modified preservation of the fine interaction between motor neurons and myofibers at the neuromuscular junction. Recent advancements in the development of in vitro models for human skeletal muscle have shown that three-dimensionality and integration of multiple cell types are both key parameters required to unveil pathophysiological relevant phenotypes. Here, we describe recent achievement reached in skeletal muscle modeling which used biomaterials for the generation of three-dimensional constructs of myotubes integrated with motor neurons., Competing Interests: None

Metastatic breast cancer cells disseminate to organs with a soft microenvironment. Whether and how the mechanical properties of the local tissue influence their response to treatment remains unclear. Here we found that a soft extracellular matrix empowers redox homeostasis. Cells cultured on a soft extracellular matrix display increased peri-mitochondrial F-actin, promoted by Spire1C and Arp2/3 nucleation factors, and increased DRP1- and MIEF1/2-dependent mitochondrial fission. Changes in mitochondrial dynamics lead to increased production of mitochondrial reactive oxygen species and activate the NRF2 antioxidant transcriptional response, including increased cystine uptake and glutathione metabolism. This retrograde response endows cells with resistance to oxidative stress and reactive oxygen species-dependent chemotherapy drugs. This is relevant in a mouse model of metastatic breast cancer cells dormant in the lung soft tissue, where inhibition of DRP1 and NRF2 restored cisplatin sensitivity and prevented disseminated cancer-cell awakening. We propose that targeting this mitochondrial dynamics- and redox-based mechanotransduction pathway could open avenues to prevent metastatic relapse., (© 2022. The Author(s), under exclusive licence to Springer Nature Limited.)

Skeletal muscle decellularization allows the generation of natural scaffolds that retain the extracellular matrix (ECM) mechanical integrity, biological activity, and three-dimensional (3D) architecture of the native tissue. Recent reports showed that in vivo implantation of decellularized muscles supports muscle regeneration in volumetric muscle loss models, including nervous system and neuromuscular junctional homing. Since the nervous system plays pivotal roles during skeletal muscle regeneration and in tissue homeostasis, support of reinnervation is a crucial aspect to be considered. However, the effect of decellularized muscles on reinnervation and on neuronal axon growth has been poorly investigated. Here, we characterized residual protein composition of decellularized muscles by mass spectrometry and we show that scaffolds preserve structural proteins of the ECM of both skeletal muscle and peripheral nervous system. To investigate whether decellularized scaffolds could per se attract neural axons, organotypic sections of spinal cord were cultured three dimensionally in vitro, in presence or in absence of decellularized muscles. We found that neural axons extended from the spinal cord are attracted by the decellularized muscles and penetrate inside the scaffolds upon 3D coculture. These results demonstrate that decellularized scaffolds possess intrinsic neurotrophic properties, supporting their potential use for the treatment of clinical cases where extensive functional regeneration of the muscle is required., (© 2020 The Authors. STEM CELLS TRANSLATIONAL MEDICINE published by Wiley Periodicals, Inc. on behalf of AlphaMed Press.)

Fabrication of three-dimensional (3D) structures and functional tissues directly in live animals would enable minimally invasive surgical techniques for organ repair or reconstruction. Here, we show that 3D cell-laden photosensitive polymer hydrogels can be bioprinted across and within tissues of live mice, using bio-orthogonal two-photon cycloaddition and crosslinking of the polymers at wavelengths longer than 850 nm. Such intravital 3D bioprinting-which does not create by-products and takes advantage of commonly available multiphoton microscopes for the accurate positioning and orientation of the bioprinted structures into specific anatomical sites-enables the fabrication of complex structures inside tissues of live mice, including the dermis, skeletal muscle and brain. We also show that intravital 3D bioprinting of donor-muscle-derived stem cells under the epimysium of hindlimb muscle in mice leads to the de novo formation of myofibres in the mice. Intravital 3D bioprinting could serve as an in vivo alternative to conventional bioprinting.

The reproduction of reliable in vitro models of human skeletal muscle is made harder by the intrinsic 3D structural complexity of this tissue. Here we coupled engineered hydrogel with 3D structural cues and specific mechanical properties to derive human 3D muscle constructs ("myobundles") at the scale of single fibers, by using primary myoblasts or myoblasts derived from embryonic stem cells. To this aim, cell culture was performed in confined, laminin-coated micrometric channels obtained inside a 3D hydrogel characterized by the optimal stiffness for skeletal muscle myogenesis. Primary myoblasts cultured in our 3D culture system were able to undergo myotube differentiation and maturation, as demonstrated by the proper expression and localization of key components of the sarcomere and sarcolemma. Such approach allowed the generation of human myobundles of ~10 mm in length and ~120 μm in diameter, showing spontaneous contraction 7 days after cell seeding. Transcriptome analyses showed higher similarity between 3D myobundles and skeletal signature, compared to that found between 2D myotubes and skeletal muscle, mainly resulting from expression in 3D myobundles of categories of genes involved in skeletal muscle maturation, including extracellular matrix organization. Moreover, imaging analyses confirmed that structured 3D culture system was conducive to differentiation/maturation also when using myoblasts derived from embryonic stem cells. In conclusion, our structured 3D model is a promising tool for modelling human skeletal muscle in healthy and diseases conditions., Competing Interests: The authors have declared that no competing interests exist.

Human induced pluripotent stem cells (hiPSCs) have a number of potential applications in stem cell biology and regenerative medicine, including precision medicine. However, their potential clinical application is hampered by the low efficiency, high costs, and heavy workload of the reprogramming process. Here we describe a protocol to reprogram human somatic cells to hiPSCs with high efficiency in 15 d using microfluidics. We successfully downscaled an 8-d protocol based on daily transfections of mRNA encoding for reprogramming factors and immune evasion proteins. Using this protocol, we obtain hiPSC colonies (up to 160 ± 20 mean ± s.d (n = 48)) in a single 27-mm 2 microfluidic chamber) 15 d after seeding ~1,500 cells per independent chamber and under xeno-free defined conditions. Only ~20 µL of medium is required per day. The hiPSC colonies extracted from the microfluidic chamber do not require further stabilization because of the short lifetime of mRNA. The high success rate of reprogramming in microfluidics, under completely defined conditions, enables hundreds of cells to be simultaneously reprogrammed, with an ~100-fold reduction in costs of raw materials compared to those for standard multiwell culture conditions. This system also enables the generation of hiPSCs suitable for clinical translation or further research into the reprogramming process.

Pathological conditions affecting skeletal muscle function may lead to irreversible volumetric muscle loss (VML). Therapeutic approaches involving acellular matrices represent an emerging and promising strategy to promote regeneration of skeletal muscle following injury. Here we investigated the ability of three different decellularised skeletal muscle scaffolds to support muscle regeneration in a xenogeneic immune-competent model of VML, in which the EDL muscle was surgically resected. All implanted acellular matrices, used to replace the resected muscles, were able to generate functional artificial muscles by promoting host myogenic cell migration and differentiation, as well as nervous fibres, vascular networks, and satellite cell (SC) homing. However, acellular tissue mainly composed of extracellular matrix (ECM) allowed better myofibre three-dimensional (3D) organization and the restoration of SC pool, when compared to scaffolds which also preserved muscular cytoskeletal structures. Finally, we showed that fibroblasts are indispensable to promote efficient migration and myogenesis by muscle stem cells across the scaffolds in vitro. This data strongly support the use of xenogeneic acellular muscles as device to treat VML conditions in absence of donor cell implementation, as well as in vitro model for studying cell interplay during myogenesis.

Hydrogels are widely used as matrices for cell growth due to the their tuneable chemical and physical properties, which mimic the extracellular matrix of natural tissue. The microfabrication of hydrogels into arbitrarily complex 3D structures is becoming essential for numerous biological applications, and in particular for investigating the correlation between cell shape and cell function in a 3D environment. Micrometric and sub-micrometric resolution hydrogel scaffolds are required to deeply investigate molecular mechanisms behind cell-matrix interaction and downstream cellular processes. We report the design and development of high resolution 3D gelatin hydrogel woodpile structures by two-photon crosslinking. Hydrated structures of lateral linewidth down to 0.5µm, lateral and axial resolution down to a few µm are demonstrated. According to the processing parameters, different degrees of polymerization are obtained, resulting in hydrated scaffolds of variable swelling and deformation. The 3D hydrogels are biocompatible and promote cell adhesion and migration. Interestingly, according to the polymerization degree, 3D hydrogel woodpile structures show variable extent of cell adhesion and invasion. Human BJ cell lines show capability of deforming 3D micrometric resolved hydrogel structures., Statement of Significance: The design and development of high resolution 3D gelatin hydrogel woodpile structures by two-photon crosslinking is reported. Significantly, topological and mechanical conditions of polymerized gelatin structures were suitable for cell accommodation in the volume of the woodpiles, leading to a cell density per unit area comparable to the bare substrate. The fabricated structures, presenting micrometric features of high resolution, are actively deformed by cells, both in terms of cell invasion within rods and of cell attachment in-between contiguous woodpiles. Possible biological targets for this 3D approach are customized 3D tissue models, or studies of cell adhesion, deformation and migration., (Copyright © 2017 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.)

This report describes a 7 year old boy with a history of recurrent respiratory infections, a 3/6 ejection systolic murmur and a right supraclavicular systolic thrill. Chest x-ray showed widening of the superior mediastinum towards the right, and barium esophagram demonstrated anterior displacement and compression of the esophagus. Cross-sectional echocardiography revealed a transverse aortic arch segment. Thus, the findings described above suggested the noninvasive diagnosis of the right cervical aortic arch. A peripheral intravenous digital subtraction angiography was necessary to evaluate the origin of the epi-aortic arteries and it proved adequate for the follow-up of these patients.