A Pilot In Vivo Study of Flexible Fully Polymeric Nerve Cuff Electrodes.

Recent trends in the field of bioelectronics have been focused on the development of electrodes that facilitate safe and efficient stimulation of nervous tissues. Novel conducting polymer (CP) based materials, such as flexible and fully polymeric conductive elastomers (CEs), constitute a promising alternative to improve on the limitations of current metallic devices. This pilot study demonstrates the performance of tripolar CE-based peripheral nerve cuffs compared to current commercial tripolar platinum-iridium (PtIr) nerve cuffs in vivo.

An Electrical Stimulation Device For In Vitro Neural Engineering.

Due to the intrinsically low turnover of neural tissues, regenerative therapies have gained significant interest in the context of degenerative diseases and injury to the central and peripheral nervous systems. Although a range of neuroregenerative strategies involving cell transplants and drugs have been explored, these are often limited by low efficacy and unwanted side effects. Electrical stimulation (ES) is thought to modulate the proliferation and differentiation of neural stem cells (NSCs), and thus it represents a promising strategy for neuroregenerative therapies.

Biohybrid neural interfaces: improving the biological integration of neural implants.

Implantable neural interfaces (NIs) have emerged in the clinic as outstanding tools for the management of a variety of neurological conditions caused by trauma or disease. However, the foreign body reaction triggered upon implantation remains one of the major challenges hindering the safety and longevity of NIs. The integration of tools and principles from biomaterial design and tissue engineering has been investigated as a promising strategy to develop NIs with enhanced functionality and performance.

Adaptive biomimicry: design of neural interfaces with enhanced biointegration.

Neural interfaces (NIs) have traditionally used inorganic device constructs paired with electrical stimulation to bypass injured or diseased electroactive tissues. These bioinert devices have significant impact on the neural tissue, being synthetic and causing large volumetric changes to the biological environment. The concept of biomimicry has become popular for tissue engineering technologies, reflecting biological properties as a component of material design.

Mind the gap: State-of-the-art technologies and applications for EEG-based brain-computer interfaces.

Brain-computer interfaces (BCIs) provide bidirectional communication between the brain and output devices that translate user intent into function. Among the different brain imaging techniques used to operate BCIs, electroencephalography (EEG) constitutes the preferred method of choice, owing to its relative low cost, ease of use, high temporal resolution, and noninvasiveness. In recent years, significant progress in wearable technologies and computational intelligence has greatly enhanced the performance and capabilities of EEG-based BCIs (eBCIs) and propelled their migration out of the laboratory and into real-world environments.

The influence of physicochemical properties on the processibility of conducting polymers: A bioelectronics perspective.

Conducting polymers (CPs) possess unique electrical and electrochemical properties and hold great potential for different applications in the field of bioelectronics. However, the widespread implementation of CPs in this field has been critically hindered by their poor processibility. There are four key elements that determine the processibility of CPs, which are thermal tunability, chemical stability, solvent compatibility and mechanical robustness.

Synthesis and characterization of osteoinductive visible light-activated adhesive composites with antimicrobial properties.

Orthopedic surgical procedures based on the use of conventional biological graft tissues are often associated with serious post-operative complications such as immune rejection, bacterial infection, and poor osseointegration. Bioresorbable bone graft substitutes have emerged as attractive alternatives to conventional strategies because they can mimic the composition and mechanical properties of the native bone. Among these, bioactive glasses (BGs) hold great potential to be used as biomaterials for bone tissue engineering owing to their biomimetic composition and high biocompatibility and osteoinductivity.

An Antimicrobial Dental Light Curable Bioadhesive Hydrogel for Treatment of Peri-Implant Diseases.

Dental implants constitute the standard of care to replace the missing teeth, which has led to an increase in the number of patients affected by peri-implant diseases (PIDs). Here, we report the development of an antimicrobial bioadhesive, GelAMP, for the treatment of PIDs. The hydrogel is based on a visible light-activated naturally-derived polymer (gelatin) and an antimicrobial peptide (AMP).

Local Immunomodulation Using an Adhesive Hydrogel Loaded with miRNA-Laden Nanoparticles Promotes Wound Healing.

Chronic wounds are characterized by impaired healing and uncontrolled inflammation, which compromise the protective role of the immune system and may lead to bacterial infection. Upregulation of miR-223 microRNAs (miRNAs) shows driving of the polarization of macrophages toward the anti-inflammatory (M2) phenotype, which could aid in the acceleration of wound healing. However, local-targeted delivery of microRNAs is still challenging, due to their low stability.

Rational Design of Microfabricated Electroconductive Hydrogels for Biomedical Applications.

Electroconductive hydrogels (ECHs) are highly hydrated 3D networks generated through the incorporation of conductive polymers, nanoparticles, and other conductive materials into polymeric hydrogels. ECHs combine several advantageous properties of inherently conductive materials with the highly tunable physical and biochemical properties of hydrogels. Recently, the development of biocompatible ECHs has been investigated for various biomedical applications, such as tissue engineering, drug delivery, biosensors, flexible electronics, and other implantable medical devices.

Engineering a naturally-derived adhesive and conductive cardiopatch.

Myocardial infarction (MI) leads to a multi-phase reparative process at the site of damaged heart that ultimately results in the formation of non-conductive fibrous scar tissue. Despite the widespread use of electroconductive biomaterials to increase the physiological relevance of bioengineered cardiac tissues in vitro, there are still several limitations associated with engineering biocompatible scaffolds with appropriate mechanical properties and electroconductivity for cardiac tissue regeneration. Here, we introduce highly adhesive fibrous scaffolds engineered by electrospinning of gelatin methacryloyl (GelMA) followed by the conjugation of a choline-based bio-ionic liquid (Bio-IL) to develop conductive and adhesive cardiopatches.

Interpenetrating network gelatin methacryloyl (GelMA) and pectin-g-PCL hydrogels with tunable properties for tissue engineering.

The design of new hydrogel-based biomaterials with tunable physical and biological properties is essential for the advancement of applications related to tissue engineering and regenerative medicine. For instance, interpenetrating polymer network (IPN) and semi-IPN hydrogels have been widely explored to engineer functional tissues due to their characteristic microstructural and mechanical properties. Here, we engineered IPN and semi-IPN hydrogels comprised of a tough pectin grafted polycaprolactone (pectin-g-PCL) component to provide mechanical stability, and a highly cytocompatible gelatin methacryloyl (GelMA) component to support cellular growth and proliferation.

Biomimetic cardiovascular platforms for in vitro disease modeling and therapeutic validation.

Bioengineered tissues have become increasingly more sophisticated owing to recent advancements in the fields of biomaterials, microfabrication, microfluidics, genetic engineering, and stem cell and developmental biology. In the coming years, the ability to engineer artificial constructs that accurately mimic the compositional, architectural, and functional properties of human tissues, will profoundly impact the therapeutic and diagnostic aspects of the healthcare industry. In this regard, bioengineered cardiac tissues are of particular importance due to the extremely limited ability of the myocardium to self-regenerate, as well as the remarkably high mortality associated with cardiovascular diseases worldwide.

Engineering Adhesive and Antimicrobial Hyaluronic Acid/Elastin-like Polypeptide Hybrid Hydrogels for Tissue Engineering Applications.

Hydrogel-based biomaterials have been widely used for tissue engineering applications because of their high water content, swellability, and permeability, which facilitate transport and diffusion of essential nutrients, oxygen, and waste across the scaffold. These characteristics make hydrogels suitable for encapsulating cells and creating a cell supportive environment that promotes tissue regeneration when implanted in vivo. This is particularly important in the context of tissues whose intrinsic regenerative capacity is limited, such as cartilage.

Photocrosslinkable Gelatin/Tropoelastin Hydrogel Adhesives for Peripheral Nerve Repair.

Suturing peripheral nerve transections is the predominant therapeutic strategy for nerve repair. However, the use of sutures leads to scar tissue formation, hinders nerve regeneration, and prevents functional recovery. Fibrin-based adhesives have been widely used for nerve reconstruction, but their limited adhesive and mechanical strength and inability to promote nerve regeneration hamper their utility as a stand-alone intervention.

In vitro and in vivo analysis of visible light crosslinkable gelatin methacryloyl (GelMA) hydrogels.

Photocrosslinkable materials have been frequently used for constructing soft and biomimetic hydrogels for tissue engineering. Although ultraviolet (UV) light is commonly used for photocrosslinking such materials, its use has been associated with several biosafety concerns such as DNA damage, accelerated aging of tissues, and cancer. Here we report an injectable visible light crosslinked gelatin-based hydrogel for myocardium regeneration.

Engineering Biodegradable and Biocompatible Bio-ionic Liquid Conjugated Hydrogels with Tunable Conductivity and Mechanical Properties.

Conventional methods to engineer electroconductive hydrogels (ECHs) through the incorporation of conductive nanomaterials and polymers exhibit major technical limitations. These are mainly associated with the cytotoxicity, as well as poor solubility, processability, and biodegradability of their components. Here, we describe the engineering of a new class of ECHs through the functionalization of non-conductive polymers with a conductive choline-based bio-ionic liquid (Bio-IL).

Engineering a sprayable and elastic hydrogel adhesive with antimicrobial properties for wound healing.

Hydrogel-based bioadhesives have emerged as alternatives for sutureless wound closure, since they can mimic the composition and physicochemical properties of the extracellular matrix. However, they are often associated with poor mechanical properties, low adhesion to native tissues, and lack of antimicrobial properties. Herein, a new sprayable, elastic, and biocompatible composite hydrogel, with broad-spectrum antimicrobial activity, for the treatment of chronic wounds is reported.

Enrichment of the Cancer Stem Phenotype in Sphere Cultures of Prostate Cancer Cell Lines Occurs through Activation of Developmental Pathways Mediated by the Transcriptional Regulator ΔNp63α.

Background: Cancer stem cells (CSC) drive prostate cancer tumor survival and metastasis. Nevertheless, the development of specific therapies against CSCs is hindered by the scarcity of these cells in prostate tissues. Suspension culture systems have been reported to enrich CSCs in primary cultures and cell lines.

Supercritical CO2 foaming of thermoplastic materials derived from maize: proof-of-concept use in mammalian cell culture applications.

Background: Foams are high porosity and low density materials. In nature, they are a common architecture. Some of their relevant technological applications include heat and sound insulation, lightweight materials, and tissue engineering scaffolds.

An influenza A/H1N1/2009 hemagglutinin vaccine produced in Escherichia coli.

Background: The A/H1N1/2009 influenza pandemic made evident the need for faster and higher-yield methods for the production of influenza vaccines. Platforms based on virus culture in mammalian or insect cells are currently under investigation. Alternatively, expression of fragments of the hemagglutinin (HA) protein in prokaryotic systems can potentially be the most efficacious strategy for the manufacture of large quantities of influenza vaccine in a short period of time.

Specific recognition of influenza A/H1N1/2009 antibodies in human serum: a simple virus-free ELISA method.

Background: Although it has been estimated that pandemic Influenza A H1N1/2009 has infected millions of people from April to October 2009, a more precise figure requires a worldwide large-scale diagnosis of the presence of Influenza A/H1N1/2009 antibodies within the population. Assays typically used to estimate antibody titers (hemagglutination inhibition and microneutralization) would require the use of the virus, which would seriously limit broad implementation.

Methodology/principal Findings: An ELISA method to evaluate the presence and relative concentration of specific Influenza A/H1N1/2009 antibodies in human serum samples is presented.