The CUGBP Elav-like family 4 (CELF4), an RNA-binding protein, is dynamically expressed in spiral ganglion neurons (SGNs) in the cochlea over development, but how Celf4 is involved in regulating hearing functions is poorly understood. In this study, we generated a Celf4± mouse line and examined changes in the first two synapses along the auditory pathways. Firstly, we found that hearing functions were largely intact in Celf4± mice, with exception of reduced amplitude for Wave II of auditory brainstem responses (ABRs) and increased delays for Wave II and IV, both in case of 4 kHz only. Secondly, we found that counts of inner and outer hair cells (IHCs and OHCs) and SGNs remained unchanged in Celf4± mice, and that the number and function of ribbon synapses between IHCs and SGNs were comparable between WT and Celf4± mice. Lastly, function of the endbulb of Held synapse, formed between auditory nerve fibers (ANFs) of SGNs and bushy cells in the cochlear nucleus, was significantly altered in Celf4± mice. Specifically, synaptic vesicle release was subtly reduced, and excitability of bushy cells was significantly dampened, likely due to a hyperpolarized resting membrane potential. Furthermore, we found that spike kinetics was significantly faster in Celf4± bushy cells, likely caused by a larger fast-inactivating A-type potassium current (IA) found in these cells. In conclusion, we found that Celf4 haploinsufficiency altered transmission at the endbulb of Held synapses in the cochlear nucleus in a significant and multifaceted manner, revealing the roles of Celf4 in regulating hearing functions. Title: Schematic representation of the experimental approach and major findings. Legend: In mice with Celf4 haploinsufficiency, we found that while function at hair cell ribbon synapses was largely preserved, transmission at the endbulb of Held synapse was significantly altered, including subtly reduced release of synaptic vesicles from the endbulb, dampened excitability in bushy cells, and accelerated spike kinetics caused by enhanced voltage-gated K+ current.

Schizantherin B (SNB), a key bioactive ingredient of the Chinese traditional medicine Schisandra chinensis, possesses anti-inflammatory and antioxidant properties. Cisplatin (CDDP) is typically used to treat various malignant tumors, however, its clinical utility is often limited by significant off-target toxicities, most notably irreversible hearing loss. Various strategies have been explored to mitigate this side effect. In this study, we investigated the protective effects of SNB against cisplatin-induced hearing loss(CIHL) as a potential preclinical therapeutic strategy. Firstly, in the ex-vivo basilar membrane, we found that SNB alleviated CDDP-induced loss of hair cells, cochlear spiral ganglion cells, and ribbon synapses. Secondly, in vivo experiments showed that SNB protected animals against CHL, returning their response close to normal level. Thirdly, in multiple tumor cell lines, we found SNB did not interfere with CDDP’s anti-tumor effects. Consistently, in a mouse model for breast cancer, we found that SNB did not obtrude CDDP’s effects in reducing tumor mass. Finally, in examining the molecular mechanisms, we found that SNB reduced both oxidative stress and cell apoptosis in the auditory cell line of HEI-OC1 during CDDP treatment, likely through the Bcl-2/Bax/cleaved-Caspase-3 signal pathways. Collectively, our study demonstrated that SNB mitigates CIHL without interfering with its therapeutic effects in treating cancer, suggesting that SNB is a potential drug candidate for preventing CIHL in cancer patients.

In the mammalian cochlea upon acoustic stimulation, outer hair cells (OHCs) push and pull the basilar membrane, amplifying its vibration and therefore expanding the dynamic range of hearing. As a result, spiking patterns in auditory nerve fibers (ANFs) are believed to be significantly different, but how the central nervous system adapts to this substantial change is poorly understood. In this study, we took advantage of Prestin-/- mice of either sex where prestin, the motor protein in OHCs, was genetically knocked out, therefore removing cochlear amplification completely without changing the cellular structure of the cochlea significantly. While exocytosis from inner hair cells in the cochlea was largely intact, transmission at the endbulb of Held synapse between ANFs and bushy cells in the cochlear nucleus was significantly changed in Prestin-/- mice. Specifically, excitability of bushy cells was significantly increased, due to combination of slightly more depolarized resting membrane potential, increased membrane input resistance, and smaller and briefer afterhyperpolarization. Furthermore, synaptic strength was greatly reduced, caused by substantial decrease in the readily releasable pool (RRP) of synaptic vesicles. Significantly, paired-pulse plasticity at this synapse was reversed from depression in WT mice to facilitation in Prestin-/- mice, likely caused by quicker refilling of RRP observed in Prestin-/- mice. In conclusion, we found that transmission at the endbulb of Held synapse is significantly altered in absence of cochlear amplification, revealing interplay between the peripheral and central processing of auditory signals that contributes to expanded dynamic range of hearing seen in mammals and humans.

Pathogenic mutations in the Gjb2 gene, encoding connexin 26, are the leading cause of autosomal recessive hereditary deafness. Gene therapy holds significant promise for treating this. Adeno-associated virus (AAV)-mediated therapeutic gene delivery has been shown to be safe and effective in restoring hearing in both animal models and human patients. However, Gjb2 gene therapy has been hindered by the limited specificity and efficiency of the available AAV vectors. In this study, we screened AAV serotypes and found that co-administration of AAV1 and AAV-ie could effectively target Gjb2-expressing cells. However, the ectopic Gjb2 expression in hair cells induced by these AAVs could cause ototoxicity, which was addressed by employing the specific promoter SCpro. Co-injection of AAV1 and AAV-ie carrying exogenous Gjb2 driven by SCpro effectively restored hearing function in Gjb2-deficient mice. Moreover, the combined AAV system can transduce the cochleae of Bama miniature pigs and AAV administration into the inner ear of cynomolgus monkeys did not impair hearing and showed negligible systemic toxicity, indicating the efficiency and safety of this gene therapy in large animals. Thus, this study provides a strategy for Gjb2 gene therapy and lays a foundation for future clinical applications.

Pathological mutations in the OTOF gene cause autosomal recessive deafness 9 (DFNB9). Although dual-adeno-associated virus (AAV) gene replacement therapy has been shown to partially rescue the hearing of patients with DFNB9, the therapeutic effects still need further exploration. To investigate the impact of different recombination strategies on the efficacy of OTOF gene therapy, we constructed five dual-AAV1 therapeutic agents using RNA or protein splicing principles. Based on the recombination strategy using RNA splicing, the AAV1-AK system rescued the hearing of Otof-/- mice to 55-70 dB, which outperformed the AAV1-AP and AAV1-TS systems. Based on protein splicing, the AAV1-intein system rescued the hearing of Otof-/- mice to 35-70 dB, which outperformed that of AAV1-AK, and the effects lasted up to 12 months after injection in both newborn and adult mice. The efficacy of otoferlin re-expression and the number and functional restoration of ribbon synapses in the AAV1-intein system were also better than the AAV1-AK system. These results show that protein recombination is more efficient than nucleic acid recombination for gene therapy in DFNB9. Therefore, this work provides not only data for optimization of DFNB9 gene therapy but also a reference for the delivery of other large genes.

Vestibular efferent neurons in the brainstem provide direct cholinergic innervation to peripheral vestibular organs, thereby modulating their sensory responsiveness. In this study, a genetically targeted mouse model with choline acetyltransferase-driven fluorescent labeling enabled the precise localization of these neurons to the dorsolateral region of the genu of the facial nerve. Whole-cell patch-clamp recordings in acute brainstem slices revealed that virtually all neurons exhibited spontaneous action potential firing, with marked heterogeneity in discharge patterns and after-hyperpolarization kinetics. Prominent A-type potassium currents were identified and found to be differentially regulated by acetylcholine and calcitonin gene-related peptide. Acute unilateral vestibular deprivation induced a bilateral enhancement of spontaneous firing, indicating sensitivity to altered sensory input. These findings define the intrinsic electrophysiological properties and neuromodulatory mechanisms of vestibular efferent neurons, providing mechanistic insight into their roles in both physiological regulation and adaptive plasticity within the vestibular system.

Otitis media is an infection of the middle ear mainly caused by bacteria, and current treatments rely heavily on antibiotics. However, the emergence of antibiotic-resistant bacterial strains seriously affects their efficacy. In our study, we found that extracellular vesicles (EVs) derived from human natural killer cells (NKs) inhibit the proliferation of both standard and levofloxacin (LVX)-resistant strains of Staphylococcus aureus in a dose-dependent manner. Moreover, compared to LVX, EVs were more effective at reducing effusion and rescuing hearing thresholds in animal models. For LVX-sensitive strains, EVs were significantly more effective in terms of curative time but not curative rate. For LVX-resistant strains, EVs were significantly more effective in terms of both curative rate and curative time when applied alone or applied jointly with LVX. In summary, we found that NK EVs are highly effective in treating otitis media, providing an alternative approach for treating this common disease.

Hearing is one of the most vital sensory functions in human beings and a crucial means of perceiving and acquiring information from the natural environment. The advancement of human society is closely linked to the development of language, with hearing serving as the foundation for verbal communication. As individuals age, the deterioration of the auditory system becomes a significant factor contributing to sensory impairments in the elderly. In addition to hearing loss, the aging of the auditory system is also associated with cognitive decline and psychosocial disorders, which severely impact the quality of life for older adults. Currently, there are no effective treatments or interventions available for addressing the aging of the auditory system. Therefore, identifying biomarkers of the auditory system aging is of great significance. The Aging Biomarker Consortium of China has conducted a comprehensive evaluation of aging biomarkers in the auditory system, focusing on three dimensions: morphological, functional, and humoral biomarkers. This initiative aims to establish a foundation for assessing the degree of aging in the auditory system and to promote the management of auditory health in an aging society, ultimately enhancing the auditory health of the elderly population both in China and globally.

The mammalian cochlea relies on outer and inner hair cells (OHCs/IHCs) for sound amplification and signal transmission. Rab3-interacting molecular binding protein 2 (RIMBP2), expressed in receptor cells and neurons at synaptic active zones, remains poorly characterized in hearing. We therefore generated a Rimbp2 knockout (KO) mouse model (Rimbp2-/-), which exhibited severe hearing loss with elevated thresholds, prolonged latencies, and reduced amplitudes in auditory brainstem response Wave I. OHC loss via apoptosis was correlated with threshold elevation. In IHCs, patch-clamp recordings revealed reduced exocytosis, including a diminished readily-releasable pool, impaired sustained release, and blocked fast endocytosis. Immunostaining showed unchanged ribbon synapse numbers but positional shifts in the basal pole of KO IHCs. These findings demonstrated RIMBP2's essential role in OHC survival and its broader regulatory functions in IHC synaptic transmission than previously recognized.

To construct the in-situ emulsification and viscosification system that is suitable for low permeability oil reservoirs characterized by high-temperature and high-salt, the amphiphilic Janus SiO2 nanoparticles and Tween 60/Imidazoline oleate surfactant system were combined. The mechanism of in-situ emulsification and viscosification system was elucidated from two aspects: The dynamic adsorption and phase conversion of surfactant, and the unique bridge structure of Janus nanoparticle stabilized emulsion. The successful synthesis of Janus SiO2 nanoparticles with varying degrees of hydrophilicity and hydrophobicity was achieved through regulating the reaction conditions. Based on emulsion stability, the optimization of the modification degree of Janus SiO2 nanoparticles was achieved. The in-situ emulsification and viscosification system was constructed by introducing Tween 60/Imidazoline oleate as dispersion aid agent and emulsifier. Notably, the in-situ emulsification and viscosification system can be stably dispersed for more than 12 hours in high-temperature and high-salt. The dispersion stability of the in-situ emulsification and viscosification system was evaluated qualitatively by visual inspection, Turbiscan stability index and monitoring particle size. The emulsification ability, emulsion stability and rheological properties of the systems with different concentrations were evaluated at 90 degrees C and a salinity of 35,000 ppm. It was found that the in-situ emulsification and viscosification system with the concentration of 0.64 wt% shows better profile control and enhanced recovery performance. This study presents a new approach for profile control using amphiphilic Janus nanoparticles and provides a promising prospect for applying nanoparticles in the field of enhanced oil recovery.

Inadequate strength and stability of active crude oil emulsions stabilized by conventional surfactants always lead to a limited plugging rate of plugging agents.Thus,to address this issue,the synthesis of amphiphilic Janus nanosheets was effectively carried out for enhancing the system performances and subsequently characterized.Based on the outcomes of orthogonal tests,an assessment was conducted on the nanosheet and surfactant formulations to optimize the enhancement of emulsion properties.The experimental demonstration of the complex system has revealed its remarkable emulsifying capability,ability to decrease interfacial tension and improve rheological behavior at high temperature(80 ℃)and high salinity(35,000 ppm)conditions.Involving probable mechanism of the system performance enhancement is elucidated by considering the synergistic effect between surfactants and nanosheets.Furthermore,variables including water-to-oil ratio,salinity,temperature and stirring intensity during operation,which affect the properties of prepared emulsions,were investigated in detail.The efficacy and stability of the complex system in obstructing medium and high permeability cores were demon-strated.Notably,the core with a high permeability of 913.58 mD exhibited a plugging rate of 98.55％.This study establishes the foundations of medium and high permeability reservoirs plugging with novel active crude oil plugging agents in severe environments.

Serving as the "eyes" and "ears" of the Internet of Things, optical and acoustic sensors are the fundamental components in hardware systems. Nowadays, mainstream hardware systems, often comprising numerous discrete sensors, conversion modules, and processing units, tend to result in complex architectures that are less efficient compared to human sensory pathways. Here, a visual-audio photodetector inspired by the human perception system is proposed to enable all-in-one visual and acoustic signal detection with computing capability. This device not only captures light but also optically records sound waves, thus achieving "watching" and "listening" within a single unit. The gate-tunable positive, negative, and zero photoresponses lead to highly programmable responsivities. This programmability enables the execution of diverse functions, including visual feature extraction, object classification, and sound wave manipulation. These results showcase the potential of expanding perception approaches in neuromorphic devices, opening up new possibilities to craft intelligent and compact hardware systems.

Aiming to address the issues of limited suitability of conventional chemical oil displacement materials for formation conditions and the serious emulsification of oil and water in the produced liquid, the innovative nano oildisplacing system with CO2-responsive behavior has been developed. This system integrates oil displacement and emulsion breaking. The efficacy of the CO2-response system in creating stable emulsions with a high capacity to decrease interfacial tension has been demonstrated. The interfacial responsive behavior of all active components, including Janus nanoparticles, sodium oleate, gums, and asphaltenes, in the emulsion system was analyzed in terms of interfacial rheology and adsorption. Additionally, the prepared system demonstrated a rapid response to CO2, effectively breaking the emulsion within 5 min. Furthermore, the oil recovery enhancing mechanism of the CO2-response system was investigated using a microscopic visualization model. The system was proved to be efficient in initiating the residual oil within pore channels. Considering the combined effectiveness of the CO2response system in terms of efficient oil displacement and rapid response, it offers valuable insights for advancing the chemical flooding technology of in enhanced oil recovery.

Adeno-associated viral (AAV) vectors are increasingly used as vehicles for gene delivery to treat hearing loss. However, lack of specificity of the transgene expression may lead to overexpression of the transgene in nontarget tissues. In this study, we evaluated the expression efficiency and specificity of transgene delivered by AAV-PHP.eB under the inner ear sensory cell-specific Myo15 promoter. Compared with the ubiquitous CAG promoter, the Myo15 promoter initiates efficient expression of the GFP fluorescence reporter in hair cells, while minimizing non-specific expression in other cell types of the inner ear and CNS. Furthermore, using the Myo15 promoter, we constructed an AAV-mediated therapeutic system with the coding sequence of OTOF gene. After inner ear injection, we observed apparent hearing recovery in Otof-/- mice, highly efficient expression of exogenous otoferlin, and significant improvement in the exocytosis function of inner hair cells. Overall, our results indicate that gene therapy mediated by the hair cell-specific Myo15 promoter has potential clinical application for the treatment of autosomal recessive deafness and yet for other hereditary hearing loss related to dysfunction of hair cells.

A prevalent recessive mutation (c.2485C>T, p.Q829X) within the OTOF gene leads to profound prelingual hearing loss. Here we show that in Otof mice harbouring a mutation (c.2482C>T, p.Q828X) homozygous to human OTOF that faithfully mimics the hearing-loss phenotype, a base editor (consisting of the deaminase ABE7.10max and the Cas9 variant SpCas9-NG) packaged in adeno-associated viruses and injected into the inner ear of the mice via the round-window membrane effectively corrected the pathogenic mutation, with no apparent off-target effects. The treatment restored the levels of the otoferlin protein in 88

Afferent synapses between inner hair cells (IHCs) and the type I spiral ganglion neurons (SGNs) in the cochlea provide over 95% of sensory signals for auditory perception in the brain. However, these afferent synapses are particularly vulnerable to damage, for example from excitotoxicity, and exposure to noise in the environment which often leads to noise-induced cochlear synaptopathy (NICS). In this study, we simulated excitotoxic trauma by incubating kainic acid, a non-desensitizing agonist for AMPA type glutamate receptors on cultured cochleae. The possible protective effects of amitriptyline against NICS were examined. We found that, in IHCs, amitriptyline reversed the decrease of Ca2+ current and exocytosis caused by excitotoxic trauma. In SGNs, amitriptyline promoted the recovery of neurite loss caused by excitotoxic trauma. Furthermore, we found that the protective effects of amitriptyline are likely mediated by suppressing apoptosis factors that were upregulated during excitotoxic trauma. In conclusion, our results suggest that amitriptyline could protect afferent synapses in the cochlea from NICS, making it a potential drug candidate for hearing protection.

The integration between infrared detection and modern microelectronics offers unique opportunities for compact and high-resolution infrared imaging. However, silicon, the cornerstone of modern microelectronics, can only detect light within a limited wavelength range (< 1100 nm) due to its bandgap of 1.12 eV, which restricts its utility in the infrared detection realm. Herein, a photo-driven fin field-effect transistor is presented, which breaks the spectral response constraint of conventional silicon detectors while achieving sensitive infrared detection. This device comprises a fin-shaped silicon channel for charge transport and a lead sulfide film for infrared light harvesting. The lead sulfide film wraps the silicon channel to form a "three-dimensional" infrared-sensitive gate, enabling the photovoltage generated at the lead sulfide-silicon junction to effectively modulate the channel conductance. At room temperature, this device realizes a broadband photodetection from visible (635 nm) to short-wave infrared regions (2700 nm), surpassing the working range of the regular indium gallium arsenide and germanium detectors. Furthermore, it exhibits low equivalent noise powers of 3.2x10(-12) WHz(-1/2) and 2.3x10(-11) WHz(-1/2) under 1550 nm and 2700 nm illumination, respectively. These results highlight the significant potential of photo-driven fin field-effect transistors in advancing uncooled silicon-based infrared detection.

Danshensu, also known as salvianic acid A, is a primary active compound extracted from a traditional Chinese herb Danshen (Salvia miltiorrhiza). While its antioxidative and neuroprotective effects are well-documented, the underlying mechanisms are poorly understood. In this study, we sought out to investigate if and how Danshensu modulates neuronal excitability and voltage-gated ionic currents in the central nervous system. We prepared brain slices of the mouse brainstem and performed patch-clamp recording in bushy cells in the anteroventral cochlear nucleus, with or without Danshensu incubation for 1 h. QX-314 was used internally to block Na+ current, while tetraethylammonium and 4-aminopyridine were used to isolate different subtypes of K+ current. We found that Danshensu of 100 μm decreased the input resistance of bushy cells by approximately 60% and shifted the voltage threshold of spiking positively by approximately 7 mV, resulting in significantly reduced excitability. Furthermore, we found this reduced excitability by Danshensu was caused by enhanced voltage-gated K+ currents in these neurons, including both low voltage-activated I K,A, by approximately 100%, and high voltage-activated I K,dr, by approximately 30%. Lastly, we found that the effect of Danshensu on K+ currents was dose-dependent in that no enhancement was found for Danshensu of 50 μm and Danshensu of 200 μm failed to cause significantly more enhancement on K+ currents when compared to that of 100 μm. We found that Danshensu reduced neuronal excitability in the central nervous system by enhancing voltage-gated K+ currents, providing mechanistic support for its neuroprotective effect widely seen in vivo.