[Analysis of hearing effects of three ossicular reconstruction methods in 123 cases of atticotomy surgery].

Retrospective analysis of clinical data of 123 patients with atticotomy, exploring the clinical characteristics of patients undergoing atticotomy and the efficacy of hearing reconstruction methods. 123 patients with atticotomy were divided into three groups according to the ossicular chain treatment method: preservation of the ossicular chain group（37 cases）, cartilage elevation of stapes group（49 cases）, and PORP group（37 cases）. The clinical characteristics of patients with atticotomy, preoperative and postoperative hearing levels of the three groups of patients, and postoperative complications were analyzed.

Translocation of telomerase reverse transcriptase coincided with ATP release in postnatal cochlear supporting cells.

The spontaneous bursts of electrical activity in the developing auditory system are derived from the periodic release of adenosine triphosphate (ATP) by supporting cells in the Kölliker's organ. However, the mechanisms responsible for initiating spontaneous ATP release have not been determined. Our previous study revealed that telomerase reverse transcriptase (TERT) is expressed in the basilar membrane during the first postnatal week.

VDR Regulates BNP Promoting Neurite Growth and Survival of Cochlear Spiral Ganglion Neurons through cGMP-PKG Signaling Pathway.

Spiral ganglion neurons (SGNs) are important for hearing, and their peripheral and central processes connect sensory cells of the Corti organ to the central nervous system. The resulting network forms a point-to-point auditory conduction. As a cardiac hormone, brain natriuretic peptide (BNP) binds to natriuretic peptide receptor type A leading to diuresis, vasodilatation, inhibition of renin and aldosterone production, and cardiac and vascular myocyte growth.

NRG1/ErbB2 axis regulated mitochondrial function and antioxidant enzymes of neural stem cells in the cochlear nucleus partially through PGC-1α.

Neuregulin-1 (NRG1)/erythroblastic leukaemia viral oncogene homologues 2 (ErbB2) pathway had been implicated in promoting differentiation and suppressing apoptosis of neuronal stem cells (NSCs) isolated from cochlear nucleus. In the current study, we aimed at determining the effects of NRG1/ErbB2 on mitochondrial (mt) function of NSCs. As expected, NRG1 increased the expression of mitofusin (Mfn) 1 and Mfn2 and decreased the expression of mitochondrial fission protein 1 (Fis1) and dynamin-related protein 1 (Drp1).

[The role of triangular space of ear canal-parotid-mastoid in the surgery for first branchial cleft anomalies].

To explore the role of triangular space of ear canal-parotid-mastoid in the operation of the first branchial cleft deformity. The clinical features and intraoperative characteristics of 25 cases with first branchial cleft anomalies who underwent surgery from September 2011 to September 2019 were analyzed, and the role of the triangular space of ear canal-parotid-mastoid in the surgery was explored. Following dissecting and lesions removel of the triangular space of ear canal-parotid-mastoid, all the lesions were resected completely.

Heme Oxygenase-1 Protects Hair Cells From Gentamicin-Induced Death.

Gentamicin ototoxicity can generate free radicals within the inner ear, leading to permanent damage to sensory hair cells (HCs) and eventually hearing loss. The following study examined the alterations of oxidative damage-related genes in the cochlea and important molecules responsible for oxidation following gentamicin injury . The RT Profiler polymerase chain reaction (PCR) array was used to screen candidate targets for treatment to prevent hearing loss caused by gentamicin.

Characteristic and Otopathogenic Analysis of a Strain Responsible for Chronic Otitis Externa in China.

, a Gram-negative rod bacterium found in marine environments, is known to cause opportunistic infections in humans, including ear infections, which can be difficult to diagnose. We investigated the microbiological and otopathogenic characteristics of a strain isolated from an ear exudate specimen obtained from a patient with chronic otitis externa to provide a basis for the future diagnosis of -associated infections. The identification of was accomplished using a combination of matrix-assisted laser desorption/ionization-time-of-flight mass spectrometry (MALDI-TOF MS), classical biochemical identification methods, and the use of -selective media and advanced molecular identification methodologies.

Influences of S100A8 and S100A9 on Proliferation of Nasopharyngeal Carcinoma Cells through PI3K/Akt Signaling Pathway.

Objective: To investigate the effects of S100A8 and S100A9 on proliferation in nasopharyngeal carcinoma cells and the regulatory effects of PI3K/Akt signaling pathway.

Methods: Nasopharyngeal carcinoma cells (CNE1) were cultured and randomly divided into three groups: control group, S100A8/S100A9 overexpression group, and siRNA S100A8/S100A9 group. CCK-8 method was used to detect the effect of S100A8 and S100A9 on the viability of nasopharyngeal carcinoma cells.

Sulforaphane attenuates cisplatin-induced hearing loss by inhibiting histone deacetylase expression.

Introduction: Cruciferous vegetables are a rich source of sulforaphane (SFN), which acts as a natural HDAC inhibitor (HDACi). Our previous study found that HDACi could restore histone acetyltransferase/histone deacetylase (HAT/HDAC) balance in the cochlea and attenuate gentamicin-induced hearing loss in guinea pigs. Here, we investigated the protective effect of SFN on cisplatin-induced hearing loss (CIHL).

Atrial Natriuretic Peptide Promotes Neurite Outgrowth and Survival of Cochlear Spiral Ganglion Neurons Through NPR-A/cGMP/PKG Signaling.

Sensorineural hearing loss (SNHL) is a dominant public health issue affecting millions of people around the globe, which is correlated with the irreversible deterioration of the hair cells and spiral ganglion neurons (SGNs) within the cochlea. Strategies using bioactive molecules that regulate neurite regeneration and neuronal survival to reestablish connections between auditory epithelium or implanted electrodes and SGN neurites would become attractive therapeutic candidates for SNHL. As an intracellular second messenger, cyclic guanosine-3',5'-monophosphate (cGMP) can be synthesized through activation of particulate guanylate cyclase-coupled natriuretic peptide receptors (NPRs) by natriuretic peptides, which in turn modulates multiple aspects of neuronal functions including neuronal development and neuronal survival.

Atrial Natriuretic Peptide Improves Neurite Outgrowth from Spiral Ganglion Neurons through a cGMP-Dependent Manner.

The spiral ganglion neurons (SGNs) are the primary afferent neurons in the spiral ganglion (SG), while their degeneration or loss would cause sensorineural hearing loss. As a cardiac-derived hormone, atrial natriuretic peptide (ANP) plays a critical role in cardiovascular homeostasis through binding to its functional receptors (NPR-A and NPR-C). ANP and its receptors are widely expressed in the mammalian nervous system where they could be implicated in the regulation of multiple neural functions.

Hsp70/Bmi1-FoxO1-SOD Signaling Pathway Contributes to the Protective Effect of Sound Conditioning against Acute Acoustic Trauma in a Rat Model.

Sound conditioning (SC) is defined as "toughening" to lower levels of sound over time, which reduces a subsequent noise-induced threshold shift. Although the protective effect of SC in mammals is generally understood, the exact mechanisms involved have not yet been elucidated. To confirm the protective effect of SC against noise exposure (NE) and the stress-related signaling pathway of its rescue, we observed target molecule changes caused by SC of low frequency prior to NE as well as histology analysis in vivo and verified the suggested mechanisms in SGNs in vitro.

Caspase inhibitor z-VAD-FMK increases the survival of hair cells after Actinomycin-D-induced damage in vitro.

Actinomycin-D (Act-D) is a highly effective chemotherapeutic agent that induces apoptosis in systemic tissues. Act-D combined with other chemotherapeutic agents exhibits ototoxic effects and causes hearing impairment. To investigate the potential toxic effects of Act-D in the inner ear, we treated cochlear organotypic cultures with varying concentrations of Act-D for different durations.

Inhibition of DHCR24 increases the cisplatin-induced damage to cochlear hair cells in vitro.

Hearing loss is a common sensory disorder that affects more than 360 million people worldwide, and is primarily caused by the loss of hair cells (HCs). Ototoxic drugs, viral infections, genetic predisposition, aging or noise all damage HCs. 3β-hydroxysteroid-Δ24 reductase (DHCR24), one enzyme in the cholesterol biosynthetic pathway, is involved in inflammation, oxidative stress and neuroprotection.

Outer hair cells isolation from postnatal Sprague-Dawley rats.

Outer hair cells (OHCs) damage is a general phenomenon in clinical disorders such as noise-induced hearing loss and drug-induced hearing loss. In order to elucidate the mechanism underlying these disorders, OHCs - its diseased region needs to be deeply investigated. However, OHCs array on the basilar membrane which contains massive cells with different types.

Upregulation of HSP60 expression in the postnatal rat cochlea and rats with drug-induced hearing loss.

Heat shock protein 60 (HSP60) is a highly conserved chaperone molecule that plays important roles in mediating some physiological and pathological functions. However, researchers have not yet determined whether HSP60 is expressed in the mammalian cochlea. This study constitutes the first investigation of the expression of HSP60 in the postnatal rat cochlea.

Regional up-regulation of NOX2 contributes to the differential vulnerability of outer hair cells to neomycin.

In hearing loss induced by aminoglycoside antibiotics, the outer hair cells (OHCs) in the basal turn are always more susceptible than OHCs in the apical turn, while the underlying mechanisms remain unknown. In this study, we reported that NAPDH oxidase 2 (NOX2) played an important role in the OHCs damage preferentially in the basal turn. Normally, NOX2 was evenly expressed in OHCs among different turns, at a relatively low level.

Decreased expression of TERT correlated with postnatal cochlear development and proliferation reduction of cochlear progenitor cells.

Cochlear progenitor cells are considered as one of the best candidates for hair cell regeneration, thus, the regulation of cochlear progenitor cell proliferation has become a focus in this field. Several genes expressed in the inner ear during postnatal development have been demonstrated to be involved in maintaining the proliferative potential of progenitor cells, but the mechanism for regulating the proliferation and differentiation of cochlear progenitor cells remains poorly understood. Telomerase reverse transcriptase (TERT) has rate limiting telomerase activity and the overexpression of TERT has been shown to promote cell proliferation in series of cell lines.

N-Acetylcysteine protects inner ear hair cells and spiral ganglion neurons from manganese exposure by regulating ROS levels.

Manganese (Mn) is an indispensable cofactor for many enzymes and a basic factor for many reproductive and metabolic pathways. However, exposure to high concentrations of Mn can result in deleterious effects on the central nervous system and peripheral nerves, including nerves associated with the auditory system. Based on our studies of cochlear organotypic cultures, Mn exposure induces a significant loss of hair cells (HCs), auditory nerve fibers (ANFs) and spiral ganglion neurons (SGNs) in a concentration-dependent manner.

Pentazocine Protects SN4741 Cells Against MPP-Induced Cell Damage via Up-Regulation of the Canonical Wnt/β-Catenin Signaling Pathway.

The Wnt/β-catenin signaling pathway has been linked to many neurodegenerative diseases including Parkinson's disease (PD). A glycoprotein named Dickkopf-1 (Dkk1) can combine with the receptor complex on cell membrane to inhibit Wnt/β-catenin signaling. Opioids, a series of compounds including morphine, fentanyl and pentazocine, have been reported to contribute to the up-regulation of Wnt/β-catenin signaling.

Minocycline attenuates noise-induced hearing loss in rats.

Noise-induced hearing loss (NIHL) is a serious health concern and prevention of hair cell death or therapeutic intervention at the early stage of NIHL is critical to preserve hearing. Minocycline is a semi-synthetic derivative of tetracycline and has been shown to have otoprotective effects in ototoxic drug-induced hearing impairment, however, whether minocycline can protect against NIHL has not been investigated. The present study demonstrated elevated ABR (auditory brainstem response) thresholds and outer hair cell loss following traumatic noise exposure, which was mitigated by intraperitoneal administration of minocycline (45mg/kg/d) for 5 consecutive days.

Combinatorial enzymatic digestion with thermolysin and collagenase type I improved the isolation and culture effects of hair cell progenitors from rat cochleae.

The high incidence of hearing loss in human combined with the lack of hair cell regeneration in mammalian cochleae had got the attention to manipulate stem/progenitor cells to participate in hair cell regeneration for years. Cochlear progenitor cells are considered as the best candidate for hair cell regeneration. However, there is not any effective and feasible way to separate hair cell progenitors from rat cochleae, yet.

A retrospective study on post-operative hearing of middle ear cholesteatoma patients with labyrinthine fistula.

Conclusions: There is no significant change in bone conduction threshold after operation, so the tympanoplasty can be done to maintain hearing when conditions allow.

Objective: To study the impact of surgical treatment on hearing of cholesteatoma patients with labyrinthine fistula.

Methods: The clinical data of 35 patients (35 ears) with labyrinthine fistula, which were caused by cholesteatoma, were analyzed retrospectively.