Cancer Modeling-on-a-Chip with Future Artificial Intelligence Integration

Cancer is one of the leading causes of death worldwide, despite the large efforts to improve the understanding of cancer biology and development of treatments. The attempts to improve cancer treatment are limited by the complexity of the local milieu in which cancer cells exist. The tumor microenvironment (TME) consists of a diverse population of tumor cells and stromal cells with immune constituents, microvasculature, extracellular matrix components, and gradients of oxygen, nutrients, and growth factors. The TME is not recapitulated in traditional models used in cancer investigation, limiting the translation of preliminary findings to clinical practice. Advances in 3D cell culture, tissue engineering, and microfluidics have led to the development of “cancer‐on‐a‐chip” platforms that expand the ability to model the TME in vitro and allow for high‐throughput analysis. The advances in the development of cancer‐on‐a‐chip platforms, implications for drug development, challenges to leveraging this technology for improved cancer treatment, and future integration with artificial intelligence for improved predictive drug screening models are discussed.fi=vertaisarvioitu|en=peerReviewed

Hydrogel‐Enabled Transfer‐Printing of Conducting Polymer Films for Soft Organic Bioelectronics

The use of conducting polymers such as poly(3,4‐ethylenedioxythiophene) polystyrene sulfonate (PEDOT:PSS) for the development of soft organic bioelectronic devices, such as organic electrochemical transistors (OECTs), is rapidly increasing. However, directly manipulating conducting polymer thin films on soft substrates remains challenging, which hinders the development of conformable organic bioelectronic devices. A facile transfer‐printing of conducting polymer thin films from conventional rigid substrates to flexible substrates offers an alternative solution. In this work, it is reported that PEDOT:PSS thin films on glass substrates, once mixed with surfactants, can be delaminated with hydrogels and thereafter be transferred to soft substrates without any further treatments. The proposed method allows easy, fast, and reliable transferring of patterned PEDOT:PSS thin films from glass substrates onto various soft substrates, facilitating their application in soft organic bioelectronics. By taking advantage of this method, skin‐attachable tattoo‐OECTs are demonstrated, relevant for conformable, imperceptible, and wearable organic biosensing.The use of hydrogels enables transfer‐printing of poly(3,4‐ethylenedioxythiophene):polystyrene sulfonate thin films from glass substrates onto various soft substrates. Taking advantage of this technique, skin‐attachable organic electrochemical transistors (OECTs) are fabricated on commercially available tattoo paper. Wearable tattoo‐OECTs are further demonstrated with the integration of a wireless readout system.Peer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/154307/1/adfm201906016.pdfhttps://deepblue.lib.umich.edu/bitstream/2027.42/154307/2/adfm201906016_am.pdfhttps://deepblue.lib.umich.edu/bitstream/2027.42/154307/3/adfm201906016-sup-0001-SuppMat.pd

How Do Bone Allografts Regenerate Bone?

utogenous bone is universally considered as the gold standard for grafting procedures, although it presents many limitations such as donor-site morbidity, and postoperative complications such as pain and bleeding. Allogenic bone matrices are excellent alter- natives to autogenous bone grafts because they overcome many of the limitations. This is why they are widely used in the field of dentistry, orthopedics, and craniofacial surgery. Bone allografts are available as mineralized (freeze-dried bone allografts) and demineralized freeze-dried bone allografts and in certain proce dures they show comparable regenerative performance to autoge nous bone grafts, and are well integrated with the host tissues However, the fundamental reasons behind the clinical success of these materials remain unclear It has been observed that demineralized bone matrix could stimulate ectopic bone formationuponits implantationimmuscular tissues. This phenomenon, led to the assumption that specific molecules are responsible for inducing bone formation, later identified as "bone morphogenetic proteins. However recent research has put doubt into this notion. Several studies have shown that the concentration of bone morphogenetic proteins in natural bone grafts is in orders of magnitudes lower than those needed to stimulate new bone formation. Then, why these materials still work so well

Glomerulus-on-a-Chip. Life Up

[No abstract available]Scopu

Electrospun biodegradable nanofibrous mats for tissue engineering

Aims & method: In this study, a microbial polyester, poly(3-hydroxybutyrate-co-3-hydroxyvalerate) (PHBV), and its blends were electrospun into PHBV (10% w/v), PHBV (15% w/v), PHBV-PLLA (5% w/v), PHBV-PLGA (50:50) (15% w/v) and PHBV-P(L,DL)LA (5% w/v) fibrous scaffolds for tissue engineering. Results: Various processing parameters affected the morphology and the dimensions of beads formed on the fibers. Concentration was highly influential on fiber properties; as it increased from 5 to 15% (w/v), fiber diameter increased from 284 133 nm to 2200 716 nm. Increase in potential (from 20 to 50 kV) did not lead to the expected decrease in fiber diameter. The blends of PHBV with lactide-based polymers led to fibers with less beads and more uniform diameter. The surface porosities for PHBV10, PHBV15, PHBV-PLLA, PHBV-PLGA (50:50) and PHBV-P(L,DL)LA were 38.0 +/- 3.8, 40.1 +/- 8.5, 53.8 +/- 4.2, 50.0 +/- 4.2 and 30.8 +/- 2.7%, respectively. In vitro studies using human osteosarcoma cells (Saos-2) revealed that the electrospun scaffolds promoted cell growth and penetration. Surface modification with oxygen plasma treatment slightly improved the improved the results in terms of cell number increase and significantly improved spreading of the cells. Conclusion: All scaffolds prepared by electrospinning have implied significant potential for use in further studies leading to bone tissue engineering applications. The PHBV-PLLA blend appeared to yield the best results regarding cell number increase, their attachment and spreading inside and on the scaffold

Advancing tissue engineering by using electrospun nanofibers

Electrospinning is a versatile technique that enables the development of nanofiber-based scaffolds, from a variety of polymers that may have drug-release properties. Using nanofibers, it is now possible to produce biomimetic scaffolds that can mimic the extracellular matrix for tissue engineering. Interestingly, nanofibers can guide cell growth along their direction. Combining factors like fiber diameter, alignment and chemicals offers new ways to control tissue engineering. In vivo evaluation of nanomats included their degradation, tissue reactions and engineering of specific tissues. New advances made in electrospinning, especially in drug delivery, support the massive potential of these nanobiomaterials. Nevertheless, there is already at least one product based on electrospun nanofibers with drug-release properties in a Phase III clinical trial, for wound dressing. Hopefully, clinical applications in tissue engineering will follow to enhance the success of regenerative therapies

Recent Advances in Cochlear Implant Electrode Array Design Parameters

© 2022 by the authors. Licensee MDPI, Basel, Switzerland.Cochlear implants are neural implant devices that aim to restore hearing in patients with severe sensorineural hearing impairment. Here, the main goal is to successfully place the electrode array in the cochlea to stimulate the auditory nerves through bypassing damaged hair cells. Several electrode and electrode array parameters affect the success of this technique, but, undoubtedly, the most important one is related to electrodes, which are used for nerve stimulation. In this paper, we provide a comprehensive resource on the electrodes currently being used in cochlear implant devices. Electrode materials, shape, and the effect of spacing between electrodes on the stimulation, stiffness, and flexibility of electrode-carrying arrays are discussed. The use of sensors and the electrical, mechanical, and electrochemical properties of electrode arrays are examined. A large library of preferred electrodes is reviewed, and recent progress in electrode design parameters is analyzed. Finally, the limitations and challenges of the current technology are discussed along with a proposal of future directions in the field