Electroacoustic Responsive Cochlea-on-a-Chip.

Organ-on-chips can highly simulate the complex physiological functions of organs, exhibiting broad application prospects in developmental research, disease simulation, as well as new drug research and development. However, there is still less concern about effectively constructing cochlea-on-chips. Here, a novel cochlear organoids-integrated conductive hydrogel biohybrid system with cochlear implant electroacoustic stimulation (EAS) for cochlea-on-a-chip construction and high-throughput drug screening, is presented. Benefiting from the superior biocompatibility and electrical property of conductive hydrogel, together with cochlear implant EAS, the inner ear progenitor cells can proliferate and spontaneously shape into spheres, finally forming cochlear organoids with good cell viability and structurally mature hair cells. By incorporating these progenitor cells-encapsulated hydrogels into a microfluidic-based cochlea-on-a-chip with culture chambers and a concentration gradient generator, a dynamic and high-throughput evaluation of inner ear disease-related drugs is demonstrated. These results indicate that the proposed cochlea-on-a-chip platform has great application potential in organoid cultivation and deafness drug evaluation.

Advances in nerve guidance conduits for peripheral nerve repair and regeneration.

Peripheral nerve injury (PNI) can cause partial or total motor and sensory nerve function, leading to physical disability and nerve pain that severely affects patients' quality of life. Autologous nerve transplantation is currently the clinically recognized gold standard, but due to its inherent limitations, researchers have been searching for alternative treatments. Nerve guidance conduits (NGCs) have attracted much attention as a favorable alternative to promote the repair and regeneration of damaged peripheral nerves. In this review, we provide an overview of the anatomy of peripheral nerves, peripheral nerve injury and repair, and current treatment methods. Importantly, different design strategies of NGCs used for the treatment of PNI and their applications in PNI repair are highlighted. Finally, an outlook on the future development and challenges of NGCs is presented.

3D Ti3C2Tx MXene-Matrigel with Electroacoustic Stimulation to Promote the Growth of Spiral Ganglion Neurons.

Cochlear implantation has become the most effective treatment method for patients with profound and total hearing loss. However, its therapeutic efficacy is dependent on the number and normal physiological function of cochlear implant-targeted spiral ganglion neurons (SGNs). Electrical stimulation can be used as an effective cue to regulate the morphology and function of excitatory cells. Therefore, it is important to develop an efficient cochlear implant electroacoustic stimulation (EAS) system to study the behavior of SGNs. In this work, we present an electrical stimulation system constructed by combining a cochlear implant and a conductive Ti3C2Tx MXene-matrigel hydrogel. SGNs were cultured in the Ti3C2Tx MXene-matrigel hydrogel and exposed to electrical stimulation transduced by the cochlear implant. It was demonstrated that low-frequency stimulation promoted the growth cone development and neurite outgrowth of SGNs as well as signal transmission between cells. This work may have potential value for the clinical application of the Ti3C2Tx MXene hydrogel to optimize the postoperative listening effect of cochlear implantation and benefit people with sensorineural hearing loss.

Two-dimensional Ti3C2Tx MXene promotes electrophysiological maturation of neural circuits.

BACKGROUND: The ideal neural interface or scaffold for stem cell therapy shall have good biocompatibility promoting survival, maturation and integration of neural stem cells (NSCs) in targeted brain regions. The unique electrical, hydrophilic and surface-modifiable properties of Ti3C2Tx MXene make it an attractive substrate, but little is known about how it interacts with NSCs during development and maturation. RESULTS: In this study, we cultured NSCs on Ti3C2Tx MXene and examined its effects on morphological and electrophysiological properties of NSC-derived neurons. With a combination of immunostaining and patch-clamp recording, we found that Ti3C2Tx MXene promotes NSCs differentiation and neurite growth, increases voltage-gated current of Ca2+ but not Na+ or K+ in matured neurons, boosts their spiking without changing their passive membrane properties, and enhances synaptic transmission between them. CONCLUSIONS: These results expand our understanding of interaction between Ti3C2Tx MXene and NSCs and provide a critical line of evidence for using Ti3C2Tx MXene in neural interface or scaffold in stem cell therapy.

Euphatexols C - G, five new triterpenoids from the latex of Euphorbia resinifera.

Five new triterpenoids named as euphatexols C - G (1-5) were isolated from the latex of Euphorbia resinifera. Their chemical structures were determined by extensive spectroscopic analysis, including IR, HRMS, 1 D and 2 D NMR data. Compounds 1-5 showed moderate anti-inflammatory activity with IC50 values of 22.30, 48.04, 21.89, 38.15 and 41.15 µM, respectively.

[Four new lanostane triterpenoids from latex of Euphorbia resinifera].

Four new lanostane triterpenoids, 3ß-hydroxy-12α-methoxylanosta-7,9(11),24-triene(1), 3ß-hydroxy-12α-methoxy-24-methylene-lanost-7,9(11)-dien(2), 3,7-dioxo-lanosta-8,24-diene(3), and 3,7-dioxo-24-methylene-lanost-8-en(4), were isolated from the latex of Euphorbia resinifera with a variety of chromatography methods. Their structures were elucidated based on spectroscopic data and/or comparison with the data reported in previous research. Compounds 1, 2, and 4 showed moderate inhibition of LPS-induced NO production by RAW264.7, with IC_(50) of 30.4, 37.5, and 28.3 µmol·L~(-1), respectively.

Applanaic acids A-C, three new highly oxygenated lanostane triterpenoids from the fruiting bodies of Ganoderma applanatum.

Three new highly oxygenated lanostane triterpenoids, applanaic acids A-C (1-3), were isolated from the fruiting bodies of the basidiomycete Ganoderma applanatum. Among them, applanaic acid B (2) possessed the Δ17(20)-double bond connection between the side chain and the tetracyclic skeleton, which was not common in the natural lanostane triterpenoids. Their structures were determined by 1D, 2D NMR and HRESIMS spectroscopic analysis. Compound 3 showed a weak acetylcholinesterase (AchE) inhibitory activity with 33.5% inhibition rate at 50 µM.[Figure: see text].

[Research progress of chemical constituents and biological activities of essential oil of Pistacia lentiscus].

Pistacia lentiscus,which belongs to foreign medicine resources,is widely distributed in the Mediterranean and Middle Eastern area. The essential oils are a mixture of several volatile compounds mainly monoterpenes and sesquiterpenes obtained from different parts of P. lentiscus by hydrodistillation. The variability of chemical composition,biological activities and content of essential oil is strongly affected by extraction technology,environmental and sex factors. It is indicated that essential oils of P. lentiscus have kinds of biological activities such as antibacterial,anticancer,anti-atherogenesis,antioxidant,anti-inflammatory and insecticidal activities.Many scholars hold the opinion that combination of different components with synergistic and/or additive actions should account for their biological activities. Due to its diverse efficacy and special taste,the essential oil of P. lentiscus has been extensively used in medicine,food and cosmetics industries. A mini review of chemical constituents and biological activities of essential oil of P. lentiscus in the past20 years is made here to provide valuable reference for the construction of " the Belt and Road".