65 research outputs found

    Hydrogel 3D in vitro tumor models for screening cell aggregation mediated drug response

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    Hydrogel-based 3D in vitro models comprising tumor ECM-mimetic biomaterials exhibit superlative potential as preclinical testing platforms for drug discovery and bioperformance screening. However, during hydrogel design and testing stages, the ideal selection between cancer cell laden 3D models or spheroid embedded hydrogel platforms remains to be elucidated. Selecting a disease-mimicking cellular arrangement within ECM hydrogels is paramount for anti-cancer therapeutics performance evaluation and may lead to differential outcomes. To investigate the effects assigned to varying cellular-arrangement, we developed dense 3D spheroid microtumors and cell-laden MG-63 osteosarcoma platforms embedded in GelMA and Matrigel ECM-mimetic scaffolds. These platforms enabled cancer cells/3D microtissues maturation and lorlatinib drug performance screening. Initial 3D spheroids assembly via the liquid overlay technique, resulted in the fabrication of dense cellular aggregates with reproducible size, morphology and necrotic core formation, thus mimicking the native tumor. Upon in vitro maturation, MG-63 spheroids encapsulated in hydrogel scaffolds exhibited significantly higher invasion and drug resistance than their cell laden hydrogel counterparts. Such data reveals inherent physiological and drug response variances among randomly distributed osteosarcoma cells and 3D spheroid-laden hydrogels. Overall, this highlights the importance of evaluating different cellular aggregation states when designing ECM-mimetic hydrogels for in vitro tumor modeling and high-throughput screening of anti-cancer therapeutics.publishe

    Bioinspired bone therapies using naringin: applications and advances

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    The use of natural compounds for treating chronic bone diseases holds remarkable potential. Among these therapeutics, naringin, a flavanone glycoside, represents one of the most promising candidates owing to its multifaceted effect on bone tissues. This review provides an up-to-date overview on naringin applications in the treatment of bone disorders, such as osteoporosis and osteoarthritis, and further highlights its potential for stem cell pro-osteogenic differentiation therapies. A critical perspective on naringin clinical translation is also provided. The topic is discussed in light of recently developed biomaterial-based approaches that potentiate its bioavailability and bioactivity. Overall, the reported pro-osteogenic, antiresorptive and antiadipogenic properties establish this flavanone as an exciting candidate for application in bone tissue engineering and regenerative medicine.publishe

    Preparation of well-dispersed chitosan/alginate hollow multilayered microcapsules for enhanced cellular internalization

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    Hollow multilayered capsules have shown massive potential for being used in the biomedical and biotechnology fields, in applications such as cellular internalization, intracellular trafficking, drug delivery, or tissue engineering. In particular, hollow microcapsules, developed by resorting to porous calcium carbonate sacrificial templates, natural-origin building blocks and the prominent Layer-by-Layer (LbL) technology, have attracted increasing attention owing to their key features. However, these microcapsules revealed a great tendency to aggregate, which represents a major hurdle when aiming for cellular internalization and intracellular therapeutics delivery. Herein, we report the preparation of well-dispersed polysaccharide-based hollow multilayered microcapsules by combining the LbL technique with an optimized purification process. Cationic chitosan (CHT) and anionic alginate (ALG) were chosen as the marine origin polysaccharides due to their biocompatibility and structural similarity to the extracellular matrices of living tissues. Moreover, the inexpensive and highly versatile LbL technology was used to fabricate core-shell microparticles and hollow multilayered microcapsules, with precise control over their composition and physicochemical properties, by repeating the alternate deposition of both materials. The microcapsules' synthesis procedure was optimized to extensively reduce their natural aggregation tendency, as shown by the morphological analysis monitored by advanced microscopy techniques. The well-dispersed microcapsules showed an enhanced uptake by fibroblasts, opening new perspectives for cellular internalization.publishe

    Freeform 3D printing using a continuous viscoelastic supporting matrix

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    Embedded bio-printing has fostered significant advances toward the fabrication of soft complex tissue-like constructs, by providing a physical support that allows the freeform shape maintenance within the prescribed spatial arrangement, even under gravity force. Current supporting materials still present major drawbacks for up-scaling embedded 3D bio-printing technology towards tissue-like constructs with clinically relevant dimensions. Herein, we report a a cost-effective and widely available supporting material for embedded bio-printing consisting on a continuous pseudo-plastic matrix of xanthan-gum (XG). This natural polisaccharide exhibits peculiar rheological properties that have enabled the rapid generation of complex volumetric 3D constructs with out of plane features. The freedom of design within the three orthogonal axes through the independent and controlled bio-printing process opens new opportunities to produce on demand large arbitrary shapes for personalized medicine. Additionally, we have demonstrated the versatile functionality of XG as a photocurable gel reservoir to engineer perfused cell-laden hydrogel constructs, addressing other practical biomedical applications such as in vitro models and organ-on-chip platforms.publishe

    Contribution of non-steroidal anti-inflammatory drugs to breast cancer treatment: In vitro and in vivo studies

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    Chronic inflammation plays a crucial role in carcinogenesis. High levels of serum prostaglandin E2 and tissue overexpression of cyclooxygenase-2 (COX-2) have been described in breast, urinary, colorectal, prostate, and lung cancers as being involved in tumor initiation, promotion, progression, angiogenesis, and immunosuppression. Non-steroidal anti-inflammatory drugs (NSAIDs) are prescribed for several medical conditions to not only decrease pain and fever but also reduce inflammation by inhibiting COX and its product synthesis. To date, significant efforts have been made to better understand and clarify the interplay between cancer development, inflammation, and NSAIDs with a view toward addressing their potential for cancer management. This review provides readers with an overview of the potential use of NSAIDs and selective COX-2 inhibitors for breast cancer treatment, highlighting pre-clinical in vitro and in vivo studies employed to evaluate the efficacy of NSAIDs and their use in combination with other antineoplastic drugs

    Challenges in spintronic platforms for biomedical applications

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    Integrated spintronic biochip platforms are being developed for portable, point-of-care, diagnostic and cytometric applications [1,2]. Hybrid systems incorporating magnetoresistive sensors are applied to neuroelectronic studies and biomedical imaging, namely magnetoencephalography and magnetocardiography. Lab-on-a-chip MR-based platforms are under development to perform biological studies at the single molecule level. This review introduces and discusses the potential and main characteristics of those MR-based biomedical devices, comparing to the existing technologies, while giving particular examples of targeted applications. Applications to the detection of DNA hybridization events (DNA-chips) [3] and antibody-antigen recognition at immunoassays (immuno-chips) [4] are discussed. Particular examples for cell free DNA and genomic sequences detection, for pathogen (Salmonella enteritidis, see Fig.1) detection and for flow cytometry (separation and counting) of CD34+ magnetically labeled cells coming from bone marrow or cord blood samples are given. Moreover, lateral immuno-assay configurations where analytes are labeled with magnetic nanoparticles are discussed. For biomedical imaging applications, field sensitivity is being pushed towards 1pT/sqrt(Hz) and below in hybrid devices incorporating flux guides with the magnetoresistive element allowing the direct detection of bio-magnetic fields (from brain and heart). For neuroelectronic applications, sensors are being incorporated in microelectrode arrays (Si and polyimide) to record spontaneous or stimulated neural activity (in vitro and in vivo, see Fig.2)

    Spintronic devices for biomedical applications

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    Spintronic devices have been proposed over the past decade for various biomedical applications. These include static or dynamic biomolecular recognition platforms ( DNA-cDNA, antibody-antigen, phage-bacteria, ), cytometer and cell separation devices and lateral bio assay platforms , microelectrode based devices for neuroelectronic applications, and hybrid sensor arrays for imaging applications [1]. The biomolecular recognition platforms include a magnetoresistive sensor array, a set of biomolecular probes ( surface immobilized or in solution) , biological targets labeled with particular magnetic micro beads or magnetic nanoparticles, and arraying architectures and microfluidics used to increase sensitivity and favour probe-target interaction. The platforms also incorporate the proper signal conditioning and processing electronics. Results will be shown for cell free DNA detection as a cancer marker indicator, and for cell detection using phage markers. For neuroelectronic applications, magnetoresistive sensors were fabricated onto Si microelectrode arrays. Experiments probe either extra cellular currents measured in mouse hypocampus slices, or spinal medulla signals probed directly with implanted magnetoresistive electrodes. For deep brain simulation and detection, sensors and electrodes are being fabricated into flexible polyimide probes. Separation between straight electrical contributions and magnetic signals is discussed. For imaging applications ( magneto cardiography) efforts continue to reach pT level detectivity at 1Hz, using hybrid MEMS/magnetoresistive sensor devices. Two architectures will be presented leading to larger DC field mechanical modulation, and therefore increased sensitivity

    Liver Fibrosis and Metabolic Alterations in Adults With alpha-1-antitrypsin Deficiency Caused by the Pi*ZZ Mutation

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    BACKGROUND & AIMS: Alpha-1 antitrypsin deficiency (AATD) is among the most common genetic disorders. Severe AATD is caused by a homozygous mutation in the SERPINA1 gene that encodes the Glu342Lys substitution (called the Pi*Z mutation, Pi*ZZ genotype). Pi*ZZ carriers may develop lung and liver diseases. Mutation- associated lung disorders have been well studied, but less is known about the effects in liver. We assessed the liver disease burden and associated features in adults with this form of AATD. METHODS: We collected data from 554 Pi*ZZ adults (403 in an exploratory cohort, 151 in a confirmatory cohort), in 9 European countries, with AATD who were homozygous for the Pi*Z mutation, and 234 adults without the Pi*Z mutation (controls), all without pre-existing liver disease. We collected data on demographic parameters, comorbidities, lung- and liver-related health, and blood samples for laboratory analysis. Liver fibrosis was assessed non-invasively via the serum tests Aspartate Aminotransferase to Platelet Ratio Index and HepaScore and via transient elastography. Liver steatosis was determined via transient elastography-based controlled attenuation parameter. We performed histologic analyses of livers from transgenic mice that overexpress the AATD-associated Pi*Z variant. RESULTS: Serum levels of liver enzymes were significantly higher in Pi*ZZ carriers vs controls. Based on non-invasive tests for liver fibrosis, significant fibrosis was suspected in 20%–36% of Pi*ZZ carriers, whereas signs of advanced fibrosis were 9- to 20-fold more common in Pi*ZZ carriers compared to non-carriers. Male sex; age older than 50 years; increased levels of alanine aminotransferase, aspartate aminotransferase, or g-glutamyl transferase; and low numbers of platelets were associated with higher liver fibrosis burden. We did not find evidence for a relationship between lung function and liver fibrosis. Controlled attenuation parameter 280 dB/m, suggesting severe steatosis, was detected in 39% of Pi*ZZ carriers vs 31% of controls. Carriers of Pi*ZZ had lower serum concentrations of triglyceride and low- and very-lowdensity lipoprotein cholesterol than controls, suggesting impaired hepatic secretion of lipid. Livers from Pi*Zoverexpressing mice had steatosis and down-regulation of genes involved in lipid secretion. CONCLUSIONS: In studies of AATD adults with the Pi*ZZ mutation, and of Pi*Z-overexpressing mice, we found evidence of liver steatosisinfo:eu-repo/semantics/publishedVersio
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