RESUMEN

The anterior cruciate ligament (ACL) is the most frequently injured ligament in the knee. The current method to treat the injured ligament is reconstruction using autografts and allografts. Reconstruction requires the regeneration of ligament, bone and their interface to ensure proper recovery. Recently, researchers have focused on using tissue-engineered scaffolds made of synthetic materials and biomaterials -such as collagen, decellularised tissues, silk and synthetic polymers produced following different manufacturing methods - for ACL reconstruction,. Different materials can be easily processed using various fabrication methods for mimicking the mechanical properties of the ACL. The advances in technologies play an important role in the production of constructions that can mimic native ACL.. The present review addresses integrative scaffold design, different challenges in the potential materials and manufacturing methods as well as future strategies for ACL repair. Furthermore, the review provides a road map to 3D printing combined with organ-on-chip technology to demonstrate the potential for cost-effective and user-friendly fabrication methods for ACL engineering. Finally, it underlines the potential of 3D bioprinting and organ-on-chip technologies for micro-engineering of ligaments and their associated environment.

Asunto(s)

Lesiones del Ligamento Cruzado Anterior , Reconstrucción del Ligamento Cruzado Anterior , Ligamento Cruzado Anterior , Lesiones del Ligamento Cruzado Anterior/cirugía , Reconstrucción del Ligamento Cruzado Anterior/métodos , Humanos , Ingeniería de Tejidos/métodos , Andamios del Tejido

RESUMEN

Idiopathic pulmonary fibrosis (IPF) remains a major clinical challenge to date. Repeated alveolar epithelial microinjuries are considered as the starting point and the key event in both the development and the progression of IPF. Various pro-fibrotic agents have been identified and shown to cause alveolar damage. In IPF, however, no leading cause of alveolar epithelial microinjuries can be identified and the exact etiology remains elusive. New results from epidemiologic studies suggest a causal relation between IPF and frequent episodes of gastric refluxes resulting in gastric microaspirations into the lung. The effect of gastric contents on the alveolar epithelium has not been investigated in detail. Here, we present a microfluidic lung epithelial wounding system that allows for the selective exposure of alveolar epithelial cells to gastric contents. The system is revealed to be robust and highly reproducible. The thereby created epithelial microwounds are of tiny dimensions and best possibly reproduce alveolar damage in the lung. We further demonstrate that exposure to gastric contents, namely hydrochloric acid (HCl) and pepsin, directly damages the alveolar epithelium. Together, this novel in vitro wounding system allows for the creation of in vivo-like alveolar microinjuries with the potential to study lung injury and alveolar wound repair in vitro.

Asunto(s)

Ácido Clorhídrico , Fibrosis Pulmonar Idiopática/inducido químicamente , Fibrosis Pulmonar Idiopática/patología , Técnicas Analíticas Microfluídicas/instrumentación , Alveolos Pulmonares/lesiones , Mucosa Respiratoria/lesiones , Mucosa Respiratoria/patología , Animales , Modelos Animales de Enfermedad , Diseño de Equipo , Análisis de Falla de Equipo , Estudios de Factibilidad , Análisis de Inyección de Flujo/instrumentación , Análisis de Inyección de Flujo/métodos , Reflujo Gastroesofágico/inducido químicamente , Reflujo Gastroesofágico/patología , Humanos , Técnicas Analíticas Microfluídicas/métodos , Alveolos Pulmonares/efectos de los fármacos , Alveolos Pulmonares/patología , Mucosa Respiratoria/efectos de los fármacos

RESUMEN

The development of a high-density active microelectrode array for in vitro electrophysiology is reported. Based on the Active Pixel Sensor (APS) concept, the array integrates 4096 gold microelectrodes (electrode separation 20 microm) on a surface of 2.5 mmx2.5 mm as well as a high-speed random addressing logic allowing the sequential selection of the measuring pixels. Following the electrical characterization in a phosphate solution, the functional evaluation has been carried out by recording the spontaneous electrical activity of neonatal rat cardiomyocytes. Signals with amplitudes from 130 microVp-p to 300 microVp-p could be recorded from different pixels. The results demonstrate the suitability of the APS concept for developing a new generation of high-resolution extracellular recording devices for in vitro electrophysiology.

Asunto(s)

Electrofisiología/instrumentación , Animales , Células Cultivadas , Oro , Microelectrodos , Miocitos Cardíacos/fisiología , Ratas

RESUMEN

We present the development of a multifunctional platform equipped with an array of silicon nitride micropipettes with dimensions allowing the implementation of extra- and intracellular operations. Micropipettes with outer diameter that ranges from 6 mum down to 300 nm and with walls thicknesses of 500 down to 150 nm are presented. The generic technology developed to fabricate these micropipettes has a number of advantages, including the ability to be implemented as ion-selective electrodes for (A) intracellular and (B) extracellular recordings and as (C) local drug microdispensers.