Planar Cell Polarity in the Multiciliated Epithelial Lining of the Mouse Eustachian Tube.

OBJECTIVES: Planar cell polarity (PCP) signaling, essential for uniform alignment and directional beating of motile cilia, has been investigated in multiciliated epithelia. As a complex structure connecting the middle ear to the nasopharynx, the eustachian tube (ET) is important in the onset of ear-nose-throat diseases. However, PCP signaling, including the orientation that is important for ciliary motility and clearance function in the ET, has not been studied. We evaluated PCP in the ET epithelium. STUDY DESIGN: Morphometric examination of the mouse ET. METHODS: We performed electron microscopy to assess ciliary polarity in the mouse ET, along with immunohistochemical analysis of PCP protein localization in the ET epithelium. RESULTS: We discovered PCP in the ET epithelium. Motile cilia were aligned in the same direction in individual and neighboring cells; this alignment manifested as ciliary polarity in multiciliated cells. Additionally, PCP proteins were asymmetrically localized between adjacent cells in the plane of the ET. CONCLUSIONS: The multiciliated ET epithelium exhibits polarization, suggesting novel structural features that may be critical for ET function. LEVEL OF EVIDENCE: NA Laryngoscope, 2024.

Detection of SARS-CoV-2 virus in middle ear effusions and its association with otitis media with effusion.

A large-scale outbreak of Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) occurred in Shanghai, China, in early December 2022. To study the incidence and characteristics of otitis media with effusion (OME) complicating SARS-CoV-2, we collected 267 middle ear effusion (MEE) samples and 172 nasopharyngeal (NP) swabs from patients. The SARS-CoV-2 virus was detected by RT-PCR targeting. The SARS-CoV-2 virus, angiotensin-converting enzyme 2 (ACE2), and transmembrane serine protease 2 (TMPRSS2) expression in human samples was examined via immunofluorescence. During the COVID-19 epidemic in 2022, the incidence of OME (3%) significantly increased compared to the same period from 2020 to 2022. Ear symptoms in patients with SARS-CoV-2 complicated by OME generally appeared late, even after a negative NP swab, an average of 9.33 ± 6.272 days after COVID-19 infection. The SARS-CoV-2 virus was detected in MEE, which had a higher viral load than NP swabs. The insertion rate of tympanostomy tubes was not significantly higher than in OME patients in 2019-2022. Virus migration led to high viral loads in MEE despite negative NP swabs, indicating that OME lagged behind respiratory infections but had a favorable prognosis. Furthermore, middle ear tissue from adult humans coexpressed the ACE2 receptor for the SARS-CoV-2 virus and the TMPRSS2 cofactors required for virus entry.

A novel intronic TCOF1 pathogenic variant in a Chinese family with Treacher Collins syndrome.

BACKGROUND: Treacher Collins syndrome (TCS; OMIM 154500) is a craniofacial developmental disorder. METHODS: To investigate the genetic features of a four-generation Chinese family with TCS, clinical examinations, hearing tests, computed tomography, whole-exome sequencing (WES), Sanger sequencing, reverse transcription (RT)-PCR, and the Minigene assay were performed. RESULTS: The probands, an 11-year-old male and his cousin exhibited typical clinical manifestations of TCS including conductive hearing loss, downward slanting palpebral fissures, and mandibular hypoplasia. Computed tomography revealed bilateral fusion of the anterior and posterior stapedial crura and malformation of the long crura of the incus. WES of both patients revealed a novel heterozygous intronic variant, i.e., c.4342 + 5_4342 + 8delGTGA (NM_001371623.1) in TCOF1. Minigene expression analysis revealed that the c.4342 + 5_4342 + 8delGTGA variant in TCOF1 caused a partial deletion of exon 24 (c.4115_4342del: p.Gly1373_Arg1448del), which was predicted to yield a truncated protein. The deletion was further confirmed via RT-PCR and sequencing of DNA from proband blood cells. A heterozygous variant in the POLR1C gene (NM_203290; exon6; c.525delG) was found almost co-segregated with the TCOF1 pathogenic variant. CONCLUSIONS: In conclusion, we identified a heterozygous TCOF1 splicing variant c.4342 + 5_4342 + 8delGTGA (splicing) in a Chinese TSC family with ossicular chain malformations and facial anomalies. Our findings broadened the spectrum of TCS variants and will facilitate diagnostics and prognostic predictions.

Microscopic Versus Endoscopic Ear Surgery for Early-Stage Glomus Tympanicum Tumors.

Purpose: Glomus tympanicum tumors are benign primary tumors of the middle ear that can be completely removed using modern surgery. We compared endoscopic ear surgery (EES) to traditional microscopic ear surgery (MES) in terms of the removal of early-stage glomus tympanicum tumors. Methods: We retrospectively reviewed 25 cases treated from 2003 to 2021 that were of Grade I or II based on the Glasscock-Jackson classification system. Overall, 18 cases underwent MES: 8 via trans-tympanic bone and 10 via canal-wall-down or canal-wall-up tympanomastoidectomy (CWDT or CWUT) and 7 underwent EES. We compared surgery durations, the lengths and costs of hospitalization, postoperative complications, and relapse rates between the two groups and among the three specific operation ways. Results: The postoperative follow-up period ranged from 1 to 19 years. There was no between-group difference in operative time or the length or cost of hospitalization. Operative time and cost of hospitalization did not show a statistically significant correlation to the three surgical procedures, whereas it was found that the group of MES via the trans-tympanic bone had shorter length of hospitalization when compared with CWUT or CWDT group. All tumors were completely resected; pulsatile tinnitus improved in all patients, and there was no major complication. Two patients who underwent CWUT or CWDT (one each) relapsed; no patient relapsed in the EES group. Conclusion: MES via the trans-tympanic bone and EES via the ear canal safely and reliably remove early-stage tumors without excessive patient discomfort.

Study of S poisoning mechanism on LaMnO3 perovskite catalyst surface based on DFT method.

The sulfur poisoning mechanism of low-temperature SCR de-NOx catalyst has always been one of the hot spots in academic circles. By studying the surface sulfur poisoning mechanism, low-temperature catalysts can be developed pertinently. In this paper, the mechanism of sulfur poisoning on the surface of LaMnO3 catalyst was studied by DFT method, and the adsorption process of sulfur oxides on the surface and its influence on SCR reaction process, as well as the morphology and decomposition process of ammonium sulfate on the surface were calculated. The results show that sulfur oxides will be adsorbed on the surface and occupy the adsorption site, which will adversely affect the subsequent SCR reaction. At the same time, ammonium sulfate will accumulate on the catalyst surface, which will lead to sulfur poisoning.

Insights into Nb doping effects on the catalytic activity and SO2 tolerance of Mn-Cu/BCN catalyst for low-temperature NH3-SCR reaction.

Biochar-based supported denitration catalysts have shown tremendous potential in reducing NOx, while improving low-temperature NH3-SCR catalytic activity and SO2 tolerance still faces great challenges. In this work, Mn7-Cu3/BCN and Mn7-Cu3-Nbx/BCN catalysts were prepared by one-step wet impregnation. The enhanced effect of Nb doping on the catalytic performance and SO2 tolerance over the Mn7-Cu3/BCN catalyst was evaluated in the temperature range of 75-275 °C. The denitrification activity test showed that the introduction of an appropriate amount of Nb increased the catalytic activity and N2 selectivity of the catalyst. The NO conversion of Mn7-Cu3-Nb0.05/BCN with an optimum doping ratio of 0.05 wt% Nb was higher than 94% at 150-275 °C. The characterization results indicated that the introduction of Nb enhanced the interaction between the active components MnOx and CuOx, accelerated the electron transfer between elements, and thus improved the Mn4+/Mnn+ and Oα/(Oα+Oß+Oγ) proportions and redox performance. On the other hand, Nb modification increased the number of weakly acidic sites, which was beneficial for the adsorption and activation of the reducing agent NH3 under low-temperature conditions. Meanwhile, Nb could significantly improve the SO2 poisoning resistance of the Mn7-Cu3/BCN-S catalyst when SO2 was added to the reaction system. The NO conversion of Mn7-Cu3-Nb0.05/BCN remained above 75% after a 13.5 h reaction under 100 ppm SO2 and 5 vol% H2O at 225 °C. By combining experimental characterization results with DFT calculation results, we effectively confirmed that Mn7-Cu3-Nb0.05/BCN had good sulfur resistance, mainly because Nb could effectively inhibit the formation of manganese sulfate and promote the decomposition of ammonium bisulfate.

Key Genes and Endoscopic Radical Surgery in Primary Middle Ear Oncocytic Papillomas.

OBJECTIVE: Papillomas originating from the Schneiderian epithelium within the middle ear are extremely rare and may be associated with a high rate of recurrence and malignant transformation. Oncocytic papillomas represent the rarest pathological subtype of such tumors. The current investigation aimed to determine whether there exists a distinct mechanism underlying the incidence of oncocytic papillomas arising primarily within the middle ear, and to explore potential treatment strategies to ensure complete removal and prevent recurrence. STUDY DESIGN: Search of the English literature for cases of middle ear papilloma and RNA sequencing analysis of three samples from one new case presenting at the Eye and ENT Hospital, Fudan University (Shanghai, China), with recurrent middle ear oncocytic papilloma, along with two normal mucosal samples. SETTING: Academic, tertiary referral hospital. PATIENT AND INTERVENTIONS: The patient underwent open mastoidectomy and endoscopic tympanoplasty twice in 6 years. Histopathology confirmed oncocytic papilloma in middle ear. The patient has been free of the disease at 18 months of follow-up without radiation, whereas the RNA-seq analysis of the samples in endoscopic operations remained nonmalignant. RESULTS: Only four cases of primary middle ear oncocytic papillomas have been reported. Recurrent masses usually originate from around the eustachian tube, which may explain the pathogenesis of this lesion. RNA-seq analysis was used to identify 1,317 (UP, 239; DOWN, 1078) differentially expressed genes between papillomas and normal mucosa. The involvement of some hub proteins (e.g., FN1, CXCL8, L10, JUN, and FOS) in the pathogenesis of primary middle ear papillomas was found to align with the observed clinical features. CONCLUSION: The middle ear oncocytic papillomas were extremely rare and remained incompletely understood. The findings of this first RNA-seq analysis of this rare tumor may serve to enhance comprehension of and aid in the management of middle ear papillomas.

Full Endoscopic Resection of Intralabyrinthine Schwannomas: A Case Series.

Objective: To investigate the technique and efficacy of fully endoscope resection of intralabyrinthine schwannomas (ILS) by transcanal transpromontorial endoscopic approach (TTEA). Study Design: Retrospective case review. Setting: Hospital. Patients: All patients who were affected by ILS, without extension to the internal auditory canal and underwent surgery with TTEA in our hospital in 2020. Intervention(s): Therapeutic. Main Outcome Measure(s): Recovery status, postoperative complications and remaining symptoms after surgery. Results: Three patients were included, all of which underwent gross total resections. The follow-up period was from 10 months to 2 years. No intraoperative and postoperative major complications were observed. There was no facial paralysis or cerebrospinal fluid leakage postoperatively. The hospitalization time of TTEA was 5 days. Three patients' vertigo was relieved after 1 week without receiving vestibular therapy. Only 1 patient complained of transient episodes of vertigo when climbing or holding heavy objects. Conclusions: TTEA has the advantages of clear vision to identify the anatomical structure, enabling complete tumor resection, reduced operation time, and faster postoperative recovery.Level of Evidence: IV.

Rab11a Is Essential for the Development and Integrity of the Stereocilia and Kinocilia in the Mammalian Organ of Corti.

The cochlea hair cells transform mechanic sounds to neural signals with a remarkable sensitivity and resolution. This is achieved via the precisely sculpted mechanotransduction apparatus of the hair cells and the supporting structure of the cochlea. The shaping of the mechanotransduction apparatus, the staircased stereocilia bundles on the apical surface of the hair cells, requires an intricate regulatory network including planar cell polarity (PCP) and primary cilia genes in orienting stereocilia bundles and building molecular machinery of the apical protrusions. The mechanism linking these regulatory components is unknown. Here, we show that a small GTPase known for its role in protein trafficking, Rab11a, is required for ciliogenesis in hair cells during development in mice. In addition, in the absence of Rab11a, stereocilia bundles lost their cohesion and integrity, and mice are deaf. These data indicate an essential role of protein trafficking in the formation of hair cell mechanotransduction apparatus, implicating a role of Rab11a or protein trafficking in linking the cilia and polarity regulatory components with the molecular machinery in building the cohesive and precisely shaped stereocilia bundles.

The co-pyrolysis of waste urea-formaldehyde resin with pine sawdust: co-pyrolysis behavior, pyrocarbon and its adsorption performance for Cr (VI).

Urea-formaldehyde (UF) resin is difficult to degrade and classified as hazardous organic waste. To address this concern, the co-pyrolysis behavior of UF resin with pine sawdust (PS) was studied, and the adsorption properties of pyrocarbon were evaluated with Cr (VI). Thermogravimetric analysis revealed that adding a small amount of PS can improve the pyrolysis behavior of UF resin. Based on the Flynn Wall Ozawa (FWO) method, the kinetics and activation energy values were estimated. It was observed that when the amount of UF resin exceeded twice that of PS, the activation energy of the reaction decreased, and they acted synergistically. The characterization of pyrocarbon samples showed that the specific surface area increased with the increase of temperature, while the content of functional groups showed the opposite trend. Intermittent adsorption experiments showed that 5UF + PS400 achieved 95% removal of 50 mg/L Cr (VI) at 0.6 g/L dosage and at pH 2. The adsorption process was consistent with the Langmuir isotherm and pseudo-second-order kinetics, and the maximum adsorption was 143.66 mg/g at 30 ℃. Furthermore, the adsorption process consisted of electrostatic adsorption, chelation, and redox reaction. Overall, this study provides a useful reference for the co-pyrolysis of UF resin and the adsorption capacity of pyrocarbon.

Involvement of Dmp1 in the Precise Regulation of Hair Bundle Formation in the Developing Cochlea.

Dentin matrix protein 1 (Dmp1) is a highly phosphorylated, extracellular matrix protein that is extensively expressed in bone and teeth but also found in soft tissues, including brain and muscle. However, the functions of Dmp1 in the mice cochlea are unknown. Our study showed that Dmp1 was expressed in auditory hair cells (HCs), with the role of Dmp1 in those cells identified using Dmp1 cKD mice. Immunostaining and scanning electron microscopy of the cochlea at P1 revealed that Dmp1 deficiency in mice resulted in an abnormal stereociliary bundle morphology and the mispositioning of the kinocilium. The following experiments further demonstrated that the cell-intrinsic polarity of HCs was affected without apparent effect on the tissue planer polarity, based on the observation that the asymmetric distribution of Vangl2 was unchanged whereas the Gαi3 expression domain was enlarged and Par6b expression was slightly altered. Then, the possible molecular mechanisms of Dmp1 involvement in inner ear development were explored via RNA-seq analysis. The study suggested that the Fgf23-Klotho endocrine axis may play a novel role in the inner ear and Dmp1 may regulate the kinocilium-stereocilia interaction via Fgf23-Klotho signaling. Together, our results proved the critical role of Dmp1 in the precise regulation of hair bundle morphogenesis in the early development of HCs.

Density Functional Study on Adsorption of NH3 and NOx on the γ-Fe2O3 (111) Surface.

γ-Fe2O3 is considered to be a promising catalyst for the selective catalytic reduction (SCR) of nitrogen oxide (NOx). In this study, first-principle calculations based on the density function theory (DFT) were utilized to explore the adsorption mechanism of NH3, NO, and other molecules on γ-Fe2O3, which is identified as a crucial step in the SCR process to eliminate NOx from coal-fired flue gas. The adsorption characteristics of reactants (NH3 and NOx) and products (N2 and H2O) at different active sites of the γ-Fe2O3 (111) surface were investigated. The results show that the NH3 was preferably adsorbed on the octahedral Fe site, with the N atom bonding to the octahedral Fe site. Both octahedral and tetrahedral Fe atoms were likely involved in bonding with the N and O atoms during the NO adsorption. The NO tended to be adsorbed on the tetrahedral Fe site though the combination of the N atom and the Fe site. Meanwhile, the simultaneous bonding of N and O atoms with surface sites made the adsorption more stable than that of single atom bonding. The γ-Fe2O3 (111) surface exhibited a low adsorption energy for N2 and H2O, suggesting that they could be adsorbed onto the surface but were readily desorbed, thus facilitating the SCR reaction. This work is conducive to reveal the reaction mechanism of SCR on γ-Fe2O3 and contributes to the development of low-temperature iron-based SCR catalysts.

Excellent operating temperature window and H2O/SO2 resistances of Fe-Ce catalyst modified by different sulfation strategies for NH3-SCR reaction.

Expecting to gain an excellent operating temperature window and superior catalytic activity of the catalyst in SCR reaction, the Fe-Ce bimetallic oxide catalyst was firstly prepared and sulfated with two different sulfation strategies by H2SO4. It is interestingly found that both the two sulfation strategies can significantly broaden the operating temperature window of the catalyst. In particular, the SFC and FCS both exhibit superior resistance to H2O + SO2, and the NOx conversion of the SFC even displays no changes in the coexistence of H2O and SO2. The characterization results show that different sulfation strategies can generate amorphous sulfate species rather than bulk sulfate species. Furthermore, more surface-adsorbed oxygen as well as higher contents of Ce3+ and Fe3+ can be obtained on the sulfated catalysts, especially for the SFC catalyst. Meanwhile, different sulfation strategies will progressively enhance the redox ability and amounts of strong acid sites, which will contribute to broadening the operating temperature window for the NH3-SCR reaction. Additionally, different sulfation methods do not change the reaction pathway of catalysts. However, the adsorption of ad-NH3 species and reactivity of ad-NOx species are significantly changed. These lead to the reaction pathway shifts to E-R direct over the SFC and the promotion of E-R and L-H mechanisms over the FCS catalyst.

Relative Humidity Affects Acute Otitis Media Visits of Preschool Children to the Emergency Department.

OBJECTIVE: The associations between climate variables and diseases such as respiratory infections, influenza, pediatric seizure, and gastroenteritis have been long appreciated. Infection is the main reason for acute otitis media (AOM) incidence. However, few previous studies explored the correlation between climatic parameters and AOM infections. The most important meteorological factors, temperature, relative humidity, and fine particulate matter (PM2.5), were included in this study. We studied the relationship between these meteorological factors and the AOM visits. MATERIALS AND METHODS: It was a retrospective cross-sectional study. A linear correlation and a linear regression model were used to explore the AOM visits and meteorological factors. RESULTS: A total of 7075 emergency department visits for AOM were identified. Relative humidity was found an independent risk factor for the AOM visits in preschool children (regression coefficient = -10.841<0, P = .039 < .05), but not in infants and school-age children. Average temperature and PM2.5 were not correlated with AOM visits. CONCLUSION: Humidity may have a significant inverse impact on the incidence of AOM in preschool-age children.

Comparison of Endoscopic Cartilage Myringoplasty in Dry and Wet Ears With Chronic Suppurative Otitis Media.

OBJECTIVES: This study compared the rate of graft success, as well as hearing improvement and dry ear time between dry ears and wet ears with otomycosis or without otomycosis in patients with chronic suppurative otitis media (CSOM) after endoscopic cartilage myringoplasty. METHODS: This retrospective study was conducted in a tertiary hospital in Shanghai. In total, 83 patients with CSOM (43 with dry ears and 40 with wet ears) were included. Among the 40 patients with CSOM and wet ears, 25 exhibited otomycosis. All patients underwent endoscopic myringoplasty, and perforations were repaired using tragal cartilage with a single-sided perichondrium. Patients were followed up for at least 6 months. Pure-tone hearing was examined preoperatively and at 3 months postoperatively. The graft uptake rate, hearing improvement, and dry ear time were compared between the groups. RESULTS: The graft success rate did not differ significantly between the dry-ear and wet-ear groups (95.35% and 90.00%, respectively). Furthermore, the graft success rate also did not differ significantly between patients with wet ears and otomycosis and those with wet ears without otomycosis (92.00% and 86.67%, respectively). Hearing gain did not differ significantly between the dry-ear and wet-ear groups. No significant difference in hearing gain was also found in patients with wet ears with or without otomycosis. However, the time to dry ear was significantly longer in the wet-ear group than in the dry-ear group. CONCLUSION: Patients with CSOM and wet ears required more time to achieve a completely healthy status. However, the graft success rate and hearing improvement were not affected by a wet middle ear and otomycosis. Thus, endoscopic myringoplasty using tragus cartilage is an effective treatment for refractory CSOM in patients with wet ears and otomycosis.

First Report of Nalanthamala psidii causing wilt disease of guava in Guangdong, China.

Guava (Psidium guajava L.) is a tropical fruit with great economic value. Guangdong is one of the most important guava production areas. In November 2019, guava wilt disease (GWD) was observed in a 10.6 HA commercial orchard in NanSha district, Guangzhou, Guangdong (22°37'37.626" N, 113°35'56.089" E). Disease incidence was up to 35%. Initially, leaves on the top of some branches became purple or yellow interveinal chlorosis, later dry. Infection severely became systemic developing vascular discoloration of stem, black root rot, eventually entire trees wilted and died. The root tissues were cut into 5-mm2 pieces and surface disinfected with 70% ethanol for 30 sec, 3 % sodium hypochlorite for 4 min, rinsed by the sterile water, then plated onto potato dextrose agar and incubated for 5 days at 25°C. A total of 8 monoconidial isolates with identical colony morphology were obtained. All formed cottony, whitish to pale yellow colonies. Conidiophores were dimorphic, penicillate and acremonium-like. Penicillate conidiophores gave rise to ovoidal, one-celled conidia (4.15 to 6.55×2.28 to 4.61 µm) (n=100) with truncated ends. Cylindrical or fusiform conidia (7.02 to 15.57×2.01 to 5.30 µm) (n=100) arose in long chains on acremonium-like conidiophores. Morphological characteristics of the isolates were consistent with those of Nalanthamala psidii (syn. Myxosporium psidii) reported by Schroers (2005). The rDNA internal transcribed spacer (ITS) and partial nuclear large-subunit ribosomal DNA (LSU) of two representative isolates (GDNS02 and GDNS08) were amplified using the primers pairs ITS4/ITS5 (White et al. 1990) and V9G/LR5 (de Hoog and Gerrits van den. 1998), respectively. The obtained sequences were deposited in GenBank under the accession nos. OM278372 to 73 (ITS) and OM278377 to 78 (LSU). BLASTn analysis showed 99.81% and 100% identities with the reported sequences of N. psidii CBS 116952 (AY864836) and CBS 110507 (AY554243). Maximum likelihood analyses of combined ITS and LSU sequences indicated that these two isolates being clustered with N. psidii strains. Pathogenicity tests were performed twice using healthy seedlings (60-70 cm height, cv. pearl). Each stem of five seedlings was wounded using a 5-mm sterile cork borer, and 5-day-old mycelium plugs of isolate GDNS08 were inoculated into the holes (25-cm above the soil line) and covered with Parafilm, sterile PDA plugs were placed into the wounds of additional 5 control seedlings. All plants were kept in a greenhouse (25℃, 80% relative humidity, 16/8-h day/night). After 3 months, all inoculated plants developed purple leaf, defoliation and wilt symptoms resembling those observed in the orchards, while the controls remained asymptomatic. Nalanthamala psidii was reisolated from the roots tissue of the inoculated plants, identity was confirmed by morphological characteristics and ITS sequence analyses as described above, but not from the controls, fulfilling Koch's postulates. Nalanthamala psidii has been previously reported as the causal agent of guava wilt in Taiwan, Philippines, South Africa and Bangladesh (Hsieh et al. 1976; Opina 1995; Schoeman et al. 1997; Alam et al. 2019). To our knowledge, this is the first report of N. psidii causing guava wilt in Guangdong, China. The outbreak of GWD in South Africa in the 1980s resulted in devastating losses to guava industry (Schoeman et al. 1997). Further research is needed to develop the integrated management to constrain this disease from spreading.

Rack1 regulates cellular patterning and polarity in the mouse cochlea.

Rack1 features seven WD40 repeats that fold into a multifaceted scaffold used to build signaling complexes in a context-dependent manner. Previous in vitro studies have revealed associations between Rack1 and many other proteins. Rack 1 is required for establishing planar cell polarity (PCP) in zebrafish and Xenopus. However, any molecular role of Rack1 in protein complexes or polarity regulation remains unclear. Here, we show that Rack1 is an essential gene in mice. Conditional knockout of Rack1 shortened the cochlear duct and induced cellular patterning defects characteristic of defective convergent extension (this PCP process is mediated by cellular junctional remodeling in the developing cochlear epithelium). Also, cochlear hair cells were no longer uniformly oriented in Rack1 conditional knockout mutants. Rack1 was enriched in the cellular cortices of sensory hair cells. In Rack1-deficient cochleae, E-cadherin expression at the cellular boundaries was greatly reduced. Together, the findings reveal a molecular role of Rack1 in PCP signaling that likely involves modulation of E-cadherin levels at the adherens junctions of the plasma membrane.

Nonlinear Dynamic Response Analysis of a Three-Stage Gear Train Based on Lightweight Calculation for Edge Equipment.

Bevel gears are widely used in aerospace transmission systems as well as modern mechanical equipment. In order to meet the needs and development of aerospace, high-speed dynamic vehicles, and various defense special equipment, higher and higher requirements are made for the high precision and stability of gear transmission systems, as well as the prediction and control of noise and vibration. Considering the nonlinear factors such as comprehensive gear error and tooth side clearance, a dynamic model of the three-stage gear transmission system is established. The relevant physical parameters, geometric parameters, and load parameters in the gear system are considered random variables to obtain the stochastic vibration model. When the random part of the random parameters is much smaller than the deterministic part, the vibration differential equation is expanded into a first-order term at the mean of the random parameter vector according to the Taylor series expansion theorem, and the ordering equation is solved numerically. Based on the improved stochastic regression method, the nonlinear dynamic response analysis of the three-stage gear train is carried out. This results in a relatively stable system when the dimensionless excitation frequency is in the range of 0.716 to 0.86 and the magnitude of the dimensionless integral meshing error is < 1.089.

The correlation between the body shape and otolithic function in patients with obstructive sleep apnea.

OBJECTIVE: To identify the typical pattern of changes of vestibular-evoked myogenic potentials (VEMPs) and explore the relationship between VEMPs and the anthropometry factors in patients with obstructive sleep apnea (OSA). METHODS: Patients diagnosed as OSA after overnight polysomnography (PSG) tests were enrolled as the study group. Healthy volunteers were recruited as the control group. Anthropometry data of the body shape and VEMPs results were collected completely. The correlation analysis was conducted among those parameters. RESULTS: Forty-nine patients with OSA who were diagnosed in the Therapy Center of Sleep-disordered Breathing in our hospital and sex- and age-matched healthy controls as well. Significant changes in ocular and cervical VEMPs (oVEMP and cVEMP) in the study group were observed, which were reduced response rates, elevated thresholds, decreased amplitudes, and prolonged first wave latencies. In oVEMP, the first wave (n1) latency was significantly correlated with weight, body mass index (BMI), neck circumference, waist circumference, hip circumference, and apnea hypopnea index (AHI). In a tentative application, combined use of BMI and oVEMP n1 latency increased the detection rate during OSA screening prior to PSG. CONCLUSION: OSA can negatively affect function of otolithic organs and their pathways. The first wave latency of the VEMPs waveform may be another important parameter to define peripheral nervous system lesions caused by systemic diseases as OSA.